eBird Trends maps reveal dramatic northward range shifts in Eastern species

Over a year ago, on a webinar hosted by the Washington Ornithological Society (WOS), John Fitzpatrick of Cornell Lab of Ornithology teased us with some screenshots of eBird Trends maps. I was mesmerized. Now, they have been released here at the eBird Science tab. These remarkable maps illustrate population trends for each species across their range, showing exactly where they are increasing (blue dots) or decreasing (red dots).

They do more than that, actually. The color of the dot is correlated to the rate of change — the % change between 2007 and 2021. Dark blue means really increasing; dark red really declining. The size of each dot is correlated to the size of the population in that area (or “relative abundance” in eBird lingo). Big dots mean there’s a lot of birds there, regardless of whether they are increasing or decreasing. If you hover over a dot, the actual numbers pop up. White dots mean the data are inconclusive or show no trend. You can read more of the details at the site, and perhaps I’ll discuss methodology on a later post.

Here’s the amazing thing — each dot represents a 27 x 27 km (16.7 x 16.7 mile) grid square, so just a bit larger than a Christmas Bird Count circle, which are 15 miles in diameter. That’s a remarkable level of detail. I joke that there’s more information in these maps than in all the ornithological research in the last ten years. That’s an overstatement, of course, because professional ornithologists study things that eBirders don’t. Nevertheless, these maps take crowdsourced data collection and present it in ways that are instantly useful for understanding species population trends at a granular level. This has profound implications for targeting conservation.

So, on to my first of probably many posts looking at these maps. My first peruse suggests they strongly support what the climate change research has been saying — that resident and short-distance migrants are shifting their ranges north. Let’s start with some common eastern species.

CLICK TO ENLARGE

To examine each map in detail, go to eBird’s Trends page, type in the species name, and then click “Trends” to the right of the species’ name.

Until now, most of the published literature on northward range shifts have been meta-analyses with conclusions such as “non-migratory species are shifting north by so many km per year”, but no maps, nor even mention of species by name. Here, we get the details in bright colors, at the species and even county level. Wow.

A few observations. For many species, they are declining where they are still common (the red dots are large), and increasing where they are less common or even rare (the blue dots are small). This probably implies that their overall population is declining. It also suggests that climate change may be hurting them in the south faster than it is helping them in the north. It takes time to establish new populations, and/or the new regions may not be as suitable as their old home. Note also that each of these species have different transition isoclines (if that’s what one would call it). For example, Red-bellied Woodpecker and Carolina Wren are increasing in Tennessee, but Tufted Titmouse are declining there.

Here are some relevant papers regarding range shifts in eastern species, but again, these maps communicate their results in new and vibrant ways:

Prince, K. and B. Zuckerberg. 2016. Climate change in our backyards: the reshuffling of North America’s winter bird communities. Global Change Biology 21(2): 572-585. We conclude that a shifting winter climate has provided an opportunity for smaller, southerly distributed species to colonize new regions and promote the formation of unique winter bird assemblages throughout eastern North America.

Rushing, C.S. et al. 2020. Migratory behavior and winter geography drive differential range shifts of eastern birds in response to recent climate change. Proceedings of the National Academy of Sciences117(23), pp.12897-12903. Since the early 1970s, species that remain in North America throughout the year, including both resident and migratory species, appear to have responded to climate change through both colonization of suitable area at the northern leading edge of their breeding distributions and adaption in place at the southern trailing edges.

Saunders et al. 2022. Unraveling a century of global change impacts on winter bird distributions in the eastern United States. Global Change Biology We conclude that climate has generally governed the winter occurrence of avifauna in space and time, while [habitat] change has played a pivotal role in driving distributional dynamics of species with limited and declining habitat availability.

The maps also support some of my previous blog posts: such as the northward expansion of Northern Cardinal, Carolina Wren, Tufted Titmouse, and Red-bellied Woodpecker, the crash of Florida’s white-eyed Eastern Towhees, certain range expansions of the Lesser Goldfinch and California Scrub-Jay, the expansion of many species from California into the Pacific Northwest, and the failure of oak-dependent species (e.g. Oak Titmouse and Nuttall’s Woodpecker) to go anywhere.

In future posts, I’ll look at range shifts in resident birds of the West, the impact of California’s fires (many encompassing several of these Trends dots), long-distance migrants, nationwide species, waterbirds, and seabirds, among other things.

Setting the record straight on the California Bee-eater of 1786

On August 1, 1785, a French expedition led by Jean François de Galaup, comte de Lapérouse (referred to as Lapérouse) set off with a goal to explore the world, both politically and scientifically. Specifically, they were to explore trading possibilities and the activities of foreign powers, both European and indigenous, map the world, and do science. On board their two vessels, L’Astrolabe and La Boussole, were experts in astronomy, geology, agriculture, botany, birds, medicine, and two illustrators.

The illustration of a “California Bee-eater”

They visited, in this order, South America, Easter Island, Hawaii, Alaska, California, various locations in East Asia, the South Pacific, and Australia. They departed Australia on March 10, 1788, bound for New Caledonia and the Solomon Islands and were never heard from again. The search for their vessels — and them — has been the subject of eight French investigations. Information gathered from 1826 to 2005 concluded that the vessels wrecked on the Solomon Island of Vanikoro and the survivors were killed by the local inhabitants.

Fortunately, at various ports of call, they shipped home reports, maps, and illustrations from their travels. While incomplete, these were eventually published as Voyage de La Pérouse autour du monde (“The voyage of La Pérouse around the world”). See also this version of the voyage.

The whole of their visit to California was a brief stay at the Spanish mission at Monterey from September 14 thru 22, 1786. As they were the first foreigners to visit the missions since they were founded in 1769, they provided a unique firsthand account. For the most part, they were appalled by the conditions of the Native “converts” and compared the mission to a slave plantation. It was because of this that I was reading Life in a California Mission, an excerpt from The Journals of Jean François de La Pérouse (Heyday Books, 1989).

This ludicrously colorized version is sold online as the “first known illustration of a California bee-eater”

There are three bird illustrations: one is a pair of California Quail, another is likely a Varied Thrush from Alaska, and the third is this one, identified as a “promerops” or bee-eater. Later publications attempt to identify it correctly, usually as a thrasher (both California and brown!). To me, it is clearly a Yellow-billed Cuckoo. The unique undertail pattern, the bill shape, and the head pattern all match well, and really match no other species. The way it is perched upright in a tree is better for cuckoo than thrasher. I can find no publication that identifies it as a cuckoo. (Nor can I find one that identifies the “Black Bird” below either.)

While eBird only shows a single record for Monterey County in September (Sept 21, 1998; Andrew Molera State Park; Don Roberson), there are a handful of other records for northern California in September. Of course, the species, virtually extirpated from the region now, would have been far more common then, presumably nesting in riparian corridors from the Carmel River to the Salinas Valley, all within the travels of the French expedition.

Here are the other two illustrations of birds.

This “Black Bird” is from Porte des Français, or Lituya Bay, Alaska, near Glacier Bay National Park. It appears to be a Varied Thrush (note Blackbird in Europe is a thrush). Thanks to Jeremy Gatten for the help on this one!

The route of the Lapérouse expedition in 1786.

Heading south for winter, more birds are choosing the Pacific Northwest

Many papers predict that bird ranges will shift northward with a warming climate (Wu et al 2018, Langham et al 2015).

Many studies have already documented that this is happening (Illán et al. 2014, Virkkala, R. and A. Lehikoinen 2014, Hitch and Leberg 2007, and La Sorte and Thompson 2007).

And some have documented poleward range shifts specifically for wintering ranges (Saunders et al 2022, Hampton 2019, Paprocki et al 2017, Prince and  Zuckerberg 2016, and Paprocki et al 2014).

I’ve previously written about an increase in insectivore bird species in winter associated with a warming climate in the Sacramento Valley. As the Putah Creek Christmas Bird Count (CBC) compiler, it was hard not to notice the trends. Cassin’s Vireo, Black-throated Gray and Townsend’s Warblers, and Western Tanagers were becoming more expected in winter. We had crossed a threshold; we didn’t get freezes anymore. My bougainvillea and cape honeysuckle, which previously clung to life in winter, were now growing and blooming year-round. Fruit and insects were available to these birds.

Now in Port Townsend, Washington, we set a local CBC record for Yellow-rumped Warblers last year. This caused me to take a closer look at the data, focusing on Passerines that are rare or uncommon, and at the northern edge of their wintering range. They are: Hermit Thrush, Cedar Waxwing, Lincoln’s Sparrow, White-crowned Sparrow, Orange-crowned Warbler, and Yellow-rumped Warbler. For each of these, the PNW is at the northern limits of their wintering range.

I looked at their numbers and trends on the Portland, Olympia, Seattle, Bellingham, and Vancouver BC CBCs since the 76th CBC (winter 1975-76). I’ve got more notes on my methodology at the end.

Results

All have increased since 1975, generally with the uptick beginning in the 1990s. Here are the results of my inquiry.

The range maps are from eBird’s Abundance Maps. Red=summer; blue=winter; purple=year-round; yellow=migration. The graphs show the birds per party hour across the five CBCs, taking the total number of birds and dividing by the total number of hours across all five counts.

Hermit Thrush

Hermit Thrush has been increasing at a rate of 4.2% per year across all the CBCs. It has been increasing across all five of the counts, most strongly in Vancouver (4.1% annual growth) and most tepid in Seattle (0.6%). The overall average   It is most common on the Portland count, which has averaged 26 Hermit Thrushes per count since 2009.

Cedar Waxwing

Of the six species I focused on, Cedar Waxwing showed some of the most erratic growth, averaging only 2.5% per year. That said, it has been above average 8 of the last 9 years. To illustrate the unpredictable nature of waxwings, they have actually been declining on the Olympia (-2.3%/yr) and Vancouver (-4.1%/yr) counts. They are increasing the most on the Portland count (3.0%/yr).

Lincoln’s Sparrow

Lincoln’s Sparrow has been increasing steadily, from near zero, at an overall rate of 3.6% per year. To put this in perspective, these five CBCs tallied 5 or fewer individuals, summed across all counts, in each of the first five years of this analysis. In each of the last five years, these counts, in aggregate, tallied between 34 and 52 individuals. Growth has been strongest on the Olympia count (4.6%/yr) and weakest on the Bellingham count (1.7%/yr).

White-crowned Sparrow

Despite the eBird map, White-crowned Sparrow is a regular overwintering species in the PNW. The five counts, in aggregate, tally between 100 and 750 individuals each year. They’ve been increasing at a rate of 1.8% per year, strongest in Seattle (3.1%/yr) and weakest in Vancouver (-2.5%/yr, the only count with declining numbers).

Orange-crowned Warbler

Orange-crowned Warbler has seen dramatic increases, averaging 5.0% per year, highest in Olympia (7.2%/yr) and lowest in Bellingham (3.2%/yr). The numbers, however, are still small. Aggregate numbers across all counts were zero five of the first eleven years of this analysis (easily seen on the graph). Double digits were not reached until 1999. The last ten years, however, have averaged 15 individuals across all the counts, making this an expected species in winter now.  

Yellow-rumped Warbler

Yellow-rumped Warbler wins the award for poster child of species increasing in winter at the northern edge of their wintering range. They’ve been increasing at a rate of 5.3% per year. Interestingly, this growth is concentrated in the south. Portland (3.7%/yr), Olympia (3.4%/yr), and Seattle (6.1%/yr) have seen the most growth, while Bellingham (-0.5%) and Vancouver (-5.0%) have seen declines. Perhaps those Fraser River winds are too cold for warblers. 

Methodology

The data includes bird per party hour for the Portland, Olympia, Seattle, Bellingham, and Vancouver BC Christmas Bird Counts from the 75th count (winter 1975-76) to the 120th count (winter 2019-20). The 121st count was impacted by the pandemic.

CBC (and Breeding Bird Survey) data is uniquely advantageous for looking at long-term trends such as climate change, as they both go back many decades with generally similar effort over time (for certain well-established counts). Nevertheless, there were some issues with this data:

  • I did not use the Portland data from the 76th thru the 82nd count, due to aberrantly low party hours relative to later counts.
  • The following data was missing entirely from the Audubon CBC database: Olympia 76th, 77th, 78th, 84th, 104th, and 110th counts; and Seattle 91st count.
  • The following counts had no (or obviously incorrect) data for party hours: Portland 104th count; Bellingham 111th, 112th, and 119th counts. Because they did have bird numbers, I approximated the party hours based on their counts in nearby years. I used 230 party hours for the Portland count and 200 party hours for the Bellingham counts.

Other climate-related bird changes in the Pacific Northwest

I’ve previously blogged about climate change and birds in the Pacific Northwest:

The invasion of the Pacific Northwest: California’s birds expand north with warmer winters looks at northward range expansions of Great Egret, Turkey Vulture, Red-shouldered Hawk, Anna’s Hummingbird, Black Phoebe, Townsend’s Warbler, and California Scrub-Jay, with some discussion of others as well. Note that Townsend’s Warbler, as a migrant that winters rarely in the PNW, fits with the group of birds described in this post.

The song of the Lesser Goldfinch: Another harbinger of a warming climate looks at increasing records in the PNW in summer.

Mapping the expansion of the California Scrub-Jay into the Pacific Northwest looks at the steady range expansion of this non-migratory species.

References

Hampton, S. 2019. Avian responses to rapid climate change: Examples from the Putah Creek Christmas Bird Count. Central Valley Birds 22(4): 77-89.

Hitch and Leberg. 2007. Breeding distributions of North American bird species moving north as a result of climate change. Conservation Biology 21(2): 534-9.

Illán et al. 2014. Precipitation and winter temperature predict long-term range-scale abundance changes in Western North American birds. Global Change Biology, 20 (11), 3351–3364.

Langham et al 2015. Conservation status of North American birds in the face of future climate change. PLoS ONE 10(9): e0135350.

La Sorte, F.A., and F.R. Thompson III. 2007. Poleward shifts in winter ranges of North American birds. Ecology 88(7):1803–1812.

Paprocki et al. 2014. Regional Distribution Shifts Help Explain Local Changes in Wintering Raptor Abundance: Implications for Interpreting Population Trends. PLoS ONE 9(1): e86814.

Paprocki et al. 2017. Combining migration and wintering counts to enhance understanding of population change in a generalist raptor species, the North American Red-tailed Hawk. The Condor, 119 (1): 98–107.

Prince, K. and B. Zuckerberg. 2016. Climate change in our backyards: the reshuffling of North America’s winter bird communities. Global Change Biology 21(2): 572-585.

Saunders et al. 2022. Unraveling a century of global change impacts on winter bird distributions in the eastern United States. Global Change Biology

Virkkala, R. and A. Lehikoinen 2014. Patterns of climate-induced density shifts of species: poleward shifts faster in northern boreal birds than in southern birds. Global Change Biology 20: 2995–3003.

Wu et al. 2018. Projected avifaunal responses to climate change across the U.S. National Park System. PLOS ONE 13(3): e0190557.

I try to maintain an updated list of references at the Birds and Climate Change Facebook group. At that page, click on Files to find the list.

A Nazca Booby, a tug, a barge, and a pit: A climate parable

At 9:30am on August 17, that is, yesterday, I got a text from another birder. A Nazca Booby had just been seen from Discovery Point near Seattle. What’s more, we knew exactly where the bird was now; it was perched on the bow of a barge being pulled by the tug Seaspan Raider.

The Nazca Booby, atop the barge, photographed by Matt Stolmeier, captain for Outer Island Excursions.

The Nazca Booby is a tropical seabird that breeds exclusively on the Galapagos Islands. When not nesting, it occurs at sea in the eastern Pacific, generally between central Mexico and northern Peru.

Breeding (orange) and non-breeding (blue) range of the Nazca Booby.

This was Washington’s third record. The first, quite possibly the same bird, was on August 14, 2020, in pretty much the same part of Puget Sound. The second was a few weeks ago also off Seattle. That one was an immature, not an adult, so we know it was a different individual. It then showed up off Victoria, providing Canada with its third record.

The Nazca Booby first arrived in the United States in California in 2013. I actually played a role in that first record, a dead beachcast bird found in the aftermath of an oil spill. Working for the state’s spill response, I brought it to the attention of the California Bird Records Committee and had experts examine the carcass for identification. That bird was not a one-off event; it was the beginning of an invasion. There were a few scattered records in the following years, followed by an explosion of 26 records in 2018 and 21 in 2019. After that, California removed the species from its “review list”. While some of these records may have been the same individuals, it is remarkable that a tropical bird previously unheard-of in the US was suddenly widespread. Oregon got its first two records in 2018 and 2019.

Sea surface temperature (SST) of 66.1F off the Washington/Oregon coast.

Checking sea surface temperatures, I see that the water off the Washington and Oregon coasts is reaching 66F in places, only 4F cooler than on the south side of the Galapagos. Zooming out, it is easy to see a route from there to here where the bird never had to encounter sea surface temps under 60F. The Strait of Juan de Fuca is in the low 50s, but it does approach 60F near Seattle.

I opened the MarineTraffic app and quickly located the Seaspan Raider. It was southwest of Edmunds, northbound at 7.3 knots. I calculated it would arrive off Port Townsend between 1 and 2pm. Birders scrambled, heading to various coastal promontories on both sides of Puget Sound. I headed to Point Wilson, where Puget Sound effectively ends and meets the Strait of Juan de Fuca. The tug, bound for Canada, would have to pass by me here.

Reports came in. The bird had flown off the barge. It was in the water off Edmunds. It took off. It was seen from both sides. No one knew where it was.

Tracking the tug using the MarineTraffic app.

This wasn’t the only booby in the Salish Sea at the moment. A Brown Booby had been photographed a few days earlier near the San Juans. That was yet another tropical seabird that had already invaded the US, with records from over forty states, including Alaska. Two decades ago, this would have been unimaginable. And this summer, 2022, was already noteworthy across the Midwest and East Coast for the mass invasion of waterbirds typically found only in Florida or the Gulf Coast. Limpkins, Wood Storks, White Ibis, Roseate Spoonbills and many others were showing up hundreds of miles north of their previously known ranges.

Scrolling thru the American Birding Association Rare Bird Alert nationwide posts, limited to just mega-rarities, here is what pops up: Brown Booby in Oklahoma, Neotropic Cormorant in North Carolina, Brown Booby in Wisconsin, two Swallow-tailed Kites in Ohio, Limpkin in Wisconsin, Neotropic Cormorant in Michigan, White Ibis in New York, Wood Stork in Pennsylvania, Heermann’s Gull in Alaska, Limpkin in Illinois, Nazca Booby in California, White Ibis in Nebraska, etc. And that doesn’t even get us back to August 1. These are all birds, mostly aquatic birds, well north of their normal ranges.

Our current rate of climate warming hasn’t been seen since the Paleocene-Eocene Thermal Maximum (PETM) 55 million years ago. Then, there were alligators within the Arctic Circle. Kind of like Nazca Boobies are now a thing in Puget Sound. Actually, our current rate of warming is much faster than then. During the PETM, the climate warmed 5C in five thousand years. The current rate of warming is eighteen times faster. Then, no one would have noticed. Now, there is 1C of warming – and, with it, dramatic changes in climate and ecology – within the lifespan of a single bird. Some seabirds are showing us that they can keep up, thanks to their ability to fly long distances. I’m not sure about the alligators. Or birds that depend, say, on oak trees. The birds can fly, but the oaks can’t.

Two hours passed. I was ready to give up and head home, my only consolation being “MAMU CF”, a Marbled Murrelet making a provisioning flight across the Sound, carrying a fish to its single chick somewhere on a moss-covered Doug fir branch a hundred feet above the forest floor, probably in the Olympic Mountains. I’d only seen that once before. Much of their range in California has been lost to fires in the past five years, so this Olympic chick is important.

The original photo of the Nazca Booby on the barge, by Alex Meilleur.

One birder, who was unable to search for the Nazca Booby, called some of the local orca boats, as he worked on some of them. He let them know about the bird, as some were near it. About twenty minutes later, texts came in. They had re-found it! It was back on the same barge, now approaching Marrowstone Point. I spun my scope south. There, beyond the ferry lane, I could make out the red and white structure of the Seaspan Raider, pulling its barge, all blurry and shimmering in the distant heat mirage, slowly chugging toward me.

Taking advantage of the outgoing tide, the Seaspan Raider was now hitting 9 knots. It is powered by two Niigata 6m G25HX diesel engines. I don’t know what kind of gas mileage it gets, but, because it presumably refueled in Washington, most of its fuel is likely conventional diesel, but a small component may be renewable diesel.

Renewable diesel is not the same as biodiesel. Biodiesel can be mixed with conventional diesel, but only in very small amounts, like 2%. Renewable diesel, on the other hand, is molecularly identical to conventional diesel. It’s a relatively new invention. Made from non-petroleum sources, such as plant and animal material, it is to conventional diesel what corn syrup is to sugar; it is a “drop-in ready” alternative fuel. It can be mixed with or substituted for conventional diesel seamlessly, with no change in gas pumps, pipelines, or engines. In fact, it burns slightly cleaner, so engines last longer. It emits fewer particulates and, most importantly, its greenhouse gas footprint is up to 80% less. Its use is already widespread in California, where two of the state’s largest refineries no longer take petroleum crude.

This is the kind of thing that should have been developed thirty years ago, just after James Hansen of NOAA briefed congress on climate change in 1986. Now it’s late. We’ve already had more than 1C of climate warming, with more coming and probably ten feet of sea level rise built into the system. Stopping carbon emissions is no longer a suitable goal. We’ve already pushed the cart down the ramp. It’s rolling. We need to reverse climate change, to change that ramp so the cart rolls back to where it was. That will require actually sucking CO2 out of the air – negative emissions – which will certainly take a hundred years under the most optimistic scenarios. So get ready for more boobies, maybe even Limpkins and alligators.

Aside about Washington: Washington further delayed action a few years ago when the Department of Ecology required an Environmental Impact Statement from Phillips 66 to convert their refinery at Cherry Point to make renewable diesel. That is to say, Phillips needed to jump through major permitting hurdles because they were changing – that is, reducing — their greenhouse gas emissions. Phillips didn’t want to wait the several years required for this, so they promptly moved their operation to California. Governor Inslee tried to intervene and save the project, but it was too late. Now BP is picking up the baton in Washington.

Renewable diesel is already in widespread use in trucks, especially in California. The ferries in San Francisco Bay are powered exclusively by it. Because diesel is similar to jet fuel, and made during the same refining process, refineries also produce what is called sustainable aviation fuel (SAF). Aircraft are currently permitted to fly with up to a 50/50 blend of SAF and conventional jet fuel. Boeing promises jets that can fly with 100% SAF by 2030. We’ll be approaching 1.5C of warming by then. Nazca Booby will almost certainly be off the rare bird review list, at least in California. Brown Boobies will be breeding on the Farallones and prospecting further north.

I watched as orca boats came and went from the barge, photographing the Nazca Booby. I was told it was on the starboard side of the roof of the little structure on the bow. The tug and barge continued up Admiralty Inlet until it was straight out from me, as close as it would pass. Slightly more than halfway across the channel, it remained blurred in heat mirage. I could see fuzzy white dots on the described rooftop, but I couldn’t tell you if they were Nazca Boobies or gulls or volleyballs. In birder’s lingo, this was going to be a ‘dip’, even though I knew exactly where the bird was and was looking at it.

My view of the tug, barge, and bird.

Mathematically, this would be at least the sixth time a Nazca Booby had passed this point, my point, my sea watch. And this time I was here, ready and waiting, and still I couldn’t see it. Were it not for the texts and the orca boats, I’d never know it was there. I kept my scope glued to it, hoping it would lift off in a distinctive flight and head directly toward me, where it would join the Caspian Terns and plunge dive right in front of me as I clicked my camera in ecstasy. But it didn’t. The tug and barge chugged north.

The bird was last seen at Partridge Point on Whidbey Island, still riding the barge. It was off the barge by Rosario Inlet. I’m guessing it jumped ship and headed toward Victoria or Smith Island.

The barge’s destination was the Lafarge Texada Quarrying Ltd. limestone mine north of Vancouver. Limestone is critical to making cement. The cement-making process is responsible for 8% of the world’s carbon emissions. Part of that is from the energy used in production, which requires a kiln heated to 1,400 degrees Celsius. But most of the emissions comes from the limestone itself. Forty percent of the weight of limestone is CO2, and this is burned off in the process. There are efforts to improve the cement-making process, to make it less dependent on limestone, to reduce its carbon emissions. That’s all coming in the future.

The limestone mine at Beale Cove, the barge’s destination.

I’m wondering about the ancient Nazca civilization in what is now Peru. It was dependent on a remarkable network of underground aqueducts that delivered mountain water to their arid home. There’s a theory that they over-harvested a certain tree, which led to erosion of riversides during heavy rains, destroying their water delivery system. I wonder if they had meetings about the problem, if they had new policies in effect, at least at the end, when it was too late.

It’s supposed to be 95F in the Seattle suburbs today. I’m not worried about missing this Nazca Booby. There will be more.

The Nazca Booby on the bow. I’m sure the scope views were better. Photo by Laura Brou.

Eastern Towhee: Can the white-eyed subspecies survive even 1.5C climate change?

Pale-eyed and red-eyed forms diverged approximately 18,000 years ago.
Photo by Melissa James/Macauley Library.
eBird abundance map for Eastern Towhee. It is resident in the southeast, but expands north in summer.

The Eastern Towhee, a bird of scrub and thickets, is a common resident in the southeast United States. One subspecies migrates north in summer.

They are a prime example of a species that is considered “Least Concern” by the International Union for Conservation of Nature (IUCN), but “High Risk” in National Audubon’s assessment of birds under climate change. In their 3.0 C scenario, they predict it would lose 83% of its current breeding range, while gaining only 23%.

This is National Audubon’s projection for the Eastern Towhee’s breeding range under just a 1.5C scenario. This would spell extinction for the white-eyed birds of Florida and the deep South.
Their winter range is not anticipated to change much.

These projections are consistent with recent literature showing poleward shifts of species ranges– of the northern edge of their range, of the southern edge, and of their range’s geographic center. The predictions for Eastern Towhee are among the most dramatic.

Recent research also suggests that non-migratory and short-distance migrants are more adaptable to climate change than are long-distance migrants, and more able to shift their ranges. Indeed, we are already seeing that with Eastern Towhee. The Audubon projections appear to be in progress.

Based on Breeding Bird Survey (BBS) data, the Eastern Towhee breeding population in Florida has declined over 50% since the late 1990s. The timing of this is consistent with worldwide ecological shifts which began in the mid-1980s.

The white-eyed subspecies appears to be already in trouble. eBirders in Florida in May and June are encountering the species half as often as they were just six years earlier.

eBird data from Florida, focusing on frequency of lists reporting the species during the May-June period, shows that the maximum frequency has fallen from 18.3% in 2015 to 8.6% in 2021.

Not all range shifts are due to climate. As a scrub specialist, the Eastern Towhee prefers habitat that is in the act of regrowth, such as after a fire or being cleared. But they don’t want a forest either. To quote the Birds of the World species account for Eastern Towhee: “As farmland is abandoned, successional changes produce suitable midseral habitats that towhees favor, and their numbers increase. But, successional time is against towhees, and their numbers decrease as seres age.” That may be the explanation for the Georgia data (orange dots), which show a decline in the late 60s and early 70s, possibly due to forest growth or land clearance for development, and then a leveling off.  

As the climate warms, many species are expanding north and/or declining in the southern part of their range. But these need not happen simultaneously. Opportunities for suitable habitat may open doors in the north, and doors may close in the south, at different times. There is evidence of Eastern Towhee expansion in Minnesota, but look at the vertical axis; it does not compare with the losses in Florida.

In Florida, the white-eyed subspecies faces extinction based on National Audubon’s 1.5C scenario. They appear to have declined dramatically in the past two decades.

Photo from National Audubon website that provides range change projections under 1.5C, 2.0C, and 3.0C scenarios.

For more on climate change impacts on birds, I invite you to join the Birds and Climate Change Facebook group.

Mountain Bird Network seeks eBirders heading into the hills

The east side of the Olympics is a staircase of thrushes. The low country is for American Robins. As you get into woodsy habitat, you’ll hear the spiral song of Swainson’s Thrushes. After that, among the tall old growth along the streams, the ethereal Varied Thrush. Finally, up near timberline, you’ll hear singing Hermit Thrushes. Freeman and colleagues are tracking how these ranges are shifting with the climate.

Two 5-minute point counts at each stop as you gain elevation. June 1 to July 15. Entered into eBird. Shared with the Mountain Bird Network.

That’s all Ben Freeman, a post-doc at University of British Columbia, is asking for. And it can be any mountain, any canyon, any road.

The details are here: Mountain Bird Network.

An example of the data and analysis.

And have a great time!

The fun part: New bird names

To get the party started, here are my proposals for new bird names for 82 species. I also provide a lot of historic and current alternatives.

Ross’s Gull’s Latin name Rhodostethia rosea can be translated as Rosy Gull. Indeed, the bird is called Rosy Gull throughout most of the world.

In a previous blogpost, I documented the history of honorific bird names in the United States. Some basic facts emerged. The practice became common in the early to mid-1800s, after most eastern species had already been given descriptive English names. Thus, 58% of honorific names are western species. They were often named by ornithologists after each other, or after colleagues or supporters, or their wives or daughters (first names for women). Remarkably a third do not have Latin names that match their English honorific name (e.g. Cassin’s Auklet is Ptychoramphus aleuticus, or Aleutian Auklet), almost always because the species was described twice, with the second time (usually Audubon) providing the honorific name. When it was realized the species had been previously described, they followed international protocol and reverted to the original Latin name.

Moving forward, the AOS is now considering new English names for potentially all species with honorific names. As controversial as that may be, coming up with new names is very much the fun part. Here is my personal exercise in that.

For each of these 82 species, I provide their current English name, the meaning of their Latin name, other historic names, the meaning of any subspecies names (leaving off the nominate subspecies), names in other languages, and, finally, my proposals for a new English name (or reverting to a previous name, as the case may be).

Caveats: 1) translating Latin is not clear-cut; there are options for each name. 2) My research on other historic names is undoubtedly incomplete; please add more in the comments. I relied largely on the Birds of the World species accounts and Grinnell and Miller (1944) for these. 3) Translating the names in other languages is definitely as much art as science. I used some online dictionaries, but it was clear they were struggling at times with the nuance. At times I felt like a bewildered traveler unfamiliar with the local slang. I encourage Native speakers to provide clarification.

I was struck that, more often than not, other languages eschewed American English honorifics. For example, Sprague’s Pipit is known as Prairie Pipit in Danish, Dutch, German, Norwegian, Polish, Slovak, Spanish, Swedish, and Turkish. Worldwide species such as Leach’s and Wilson’s Storm-Petrel are predominately known by other names around the world (e.g. Northern and Oceanic Storm-Petrel, respectively, among other names).

This opens the door to a rich tableau of alternative names. Hands down my favorite non-English name goes to Haitian Creole’s moniker for Blackburnian Warbler: Little Flamboyant Warbler. A special shout-out to Icelandic, Norwegian, Polish, and Slovak, which almost always avoid honorifics and use a descriptive moniker. I became a big fan of Norwegian, which often relies on habitat-based names (e.g. Chaparral Sparrow for Bell’s Sparrow, Yucca Oriole for Scott’s Oriole).

The Norwegian list also includes several indigenous-based names (e.g. Eskimo Goose, Navajo Thrasher, Shoshone Sparrow, and Apache Sparrow). Following guidance on tribal consultation (“nothing about us without us”), the selection of such a name should involve discussions with relevant tribes. I’ll dedicate a blog post to indigenous-based names in the future.

Regarding my proposed new names, I gave priority to previous historic names, whether they be in English or derived from Latin, as well as to ideas from other languages. I am confident that others can come up with gems that are better proposals than mine.

Originally called the Horned Wavey, the bird is known as the White Goose, Dwarf Goose, and Eskimo Goose in other languages.

Ross’s Goose

  • Meaning of Latin name: Ross’s Goose
  • Other historic names: Horned Wavey, Ross Snow Goose
  • Names in other languages: White (Croatian, Czech), Dwarf/Pygmy (Danish, Swedish), Eskimo (Finnish, Norwegian), Lesser/Little Snow (German, Portuguese, Slovenian, Turkish), Blizzard (Polish), Snowflake (Slovak)
  • My proposals: Little Snow Goose, Ivory Goose

Steller’s Eider

  • Meaning of Latin name: Steller’s Eider
  • Other historic names:
  • Names in other languages: Bald (Czech), Siberian (Lithuanian), Lesser (Slovak, Spanish), Russian (Slovenian), Bird-that-sat-in-the-campfire (Inupiat)
  • My proposals: Fire Eider, Charred Eider, Flaming Eider, Flammulated Eider

Barrow’s Goldeneye

  • Meaning of Latin name: Iceland Goldeneye
  • Other historic names:
  • Names in other languages: American (Finish), Iceland (most languages)
  • My proposals: Crescent Goldeneye, Northern Goldeneye
Described in the 1800s, birds of the southwest disproportionately have honorific names. This quail frequents dry washes filled with mesquite.

Gambel’s Quail

  • Meaning of Latin name: Gambel’s Quail
  • Other historic names: Desert Quail
  • Meaning of subspecies names: Forgiving/Gracious, Pemberton’s, Tawny-breasted, Stephens’s
  • Names in other languages: Desert (Finnish), Helmeted (German), Black-bellied (Norwegian), Pointed (Polish), Headbanded (Slovak), Oak (Swedish)
  • My proposals: Mesquite Quail, Arroyo Quail, Desert Quail

Clark’s Grebe

  • Meaning of Latin name: Clark’s Grebe
  • Other historic names:
  • Meaning of subspecies names: Transitional
  • Names in other languages: Mexican (Finnish), White-faced (French), Yellow-billed (Norwegian, Polish), White-fronted (Slovak), Orange-billed (Spanish-Mexico)
  • My proposals: Elegant Grebe, White-faced Grebe, Pallid Grebe

Vaux’s Swift

  • Meaning of Latin name: Vaux’s Swift
  • Other historic names: American Swift, Oregon Swift
  • Meaning of subspecies names: Gaumer’s, Tamaulipas, Richmond’s, Pale-rumped, Invisible
  • Names in other languages: Gray-bellied (German, Polish), Brown (Norwegian), Common (Spanish-Costa Rica)
  • My proposals: Forest Swift
Known previously as Magnificent, and then reverting to Rivoli’s when split, it’s Latin name is Glittering Hummingbird.

Rivoli’s Hummingbird

  • Meaning of Latin name: Glittering Hummingbird
  • Other historic names: Magnificent (when lumped with Talamanca Hummingbird)
  • Names in other languages: Purple-crowned Brilliant Hummingbird (German), Glowing Brim (Icelandic), Purple (Norwegian), Thin-billed Amethyst (Polish), Honey (Slovak), Magnificent (Spanish)
  • My proposals: Glittering Hummingbird

Anna’s Hummingbird

  • Meaning of Latin name: Anna’s Hummingbird
  • Other historic names:
  • Meaning of subspecies names: Sedentary
  • Names in other languages: Red-faced (Norwegian), Ruby-bearded (Finnish), Red-headed (Spanish-Mexico)
  • My proposals: Winter Hummingbird

Costa’s Hummingbird

  • Meaning of Latin name: Costa’s Hummingbird
  • Other historic names: Ruffed Hummingbird, Coast Hummingbird
  • Names in other languages: Violet-headed (German, Spanish-Mexico), Desert (Norwegian), California (Polish)
  • My proposals: Desert Hummingbird, Xeric Hummingbird

Allen’s Hummingbird

  • Meaning of Latin name: Nuu-chah-nulth (Nootka) for “hummingbird” (so really meant for Rufous)
  • Other historic names: Nootka Hummingbird (original Latin name for Rufous, with which Allen’s was lumped)
  • Names in other languages: Green-backed Cinnamon/Rufous (German), Chaparral (Norwegian), California (Polish)
  • My proposals: Pacific Hummingbird, Coastal Hummingbird, California Hummingbird, Chumash Hummingbird

Ridgway’s Rail

  • Meaning of Latin name: Plain Rail
  • Other historic names: Clapper Rail (when lumped), Red-breasted Rail
  • Meaning of subspecies names: Light-footed, Belding’s, Yuma
  • Names in other languages: California (Dutch, French, Polish, Slovak), Pacific Coast (Spanish-Mexico)
  • My proposals: Pacific Rail

Wilson’s Plover

  • Meaning of Latin name: Wilson’s Plover
  • Other historic names: Belding Plover
  • Meaning of subspecies names: Belding’s, Cinnamon, Thick-billed
  • Names in other languages: Thick-billed (Dutch, Finnish, Norwegian, Slovak, Spanish), Necklaced (Haitian), Tidal/Tideland (Icelandic), Big-eyed (Polish), Beaked (Portuguese), Beach Puppet (Spanish-Cuba), Maritime (Spanish-Puerto Rico), Coastal (Turkish), Sea Runner (Swedish)
  • My proposals: Beach Plover, Large-billed Plover
Baird’s, a short-grass specialist with an incredible migration, is the sand-colored sandpiper. There are a lot of potential names to chose from.

Baird’s Sandpiper

  • Meaning of Latin name: Baird’s Sandpiper
  • Other historic names:
  • Names in other languages: Long-winged (Czech, Polish, Turkish), Eskimo (Finnish), Clay (Icelandic), Yellow-breasted (Norwegian, Swedish), Fine-billed (Portuguese, Spanish-Uruguay), Gravel (Slovenian), Plain (Spanish-Argentina, Paraguay)
  • My proposals: Arenaceous Sandpiper, Nunavut Sandpiper, Long-winged Sandpiper

Wilson’s Snipe

  • Meaning of Latin name: Delicate/Elegant Snipe
  • Other historic names:
  • Names in other languages: American (Danish, Dutch, Finnish, Hungarian, Polish, Russian, Serbian), North American (Czech, Spanish-Mexico), Short-legged (Haitian), Indian (Norwegian), Shrill (Spanish-Venezuela)
  • My proposals: Elegant Snipe, Winnowing Snipe

Wilson’s Phalarope

  • Meaning of Latin name: Tricolored Phalarope
  • Other historic names:
  • Names in other languages: Tricolored (Croatian, Polish, Serbian, Slovak, Slovenian, Spanish), Long-billed (Czech, Spanish-Mexico, Venezuela), American (Danish, Finnish, Latvian, Romanian), Large/Great (Dutch, Lithuanian, Turkish), White-tailed (Norwegian), Common (Spanish-Argentina, Uruguay)
  • My proposals: Tricolored Phalarope

Kittlitz’s Murrelet

  • Meaning of Latin name: Short-billed Murrelet
  • Other historic names:
  • Names in other languages: Short-billed (Finnish, German, Norwegian, Polish, Spanish), Mountain (Icelandic), Gray (Slovak), Brown (Swedish)
  • My proposals: Glacier Murrelet, Short-billed Murrelet

Scripps’s Murrelet

  • Meaning of Latin name: Scripps’s Murrelet
  • Other historic names: Xantus’s (when lumped with Craveri’s and Guadalupe)
  • Names in other languages: Black-tailed (Croatian), California (German, Norwegian, Spanish, Swedish), Mourning (Polish), White-winged California (Spanish-Mexico)
  • My proposals: California Murrelet

Craveri’s Murrelet

  • Meaning of Latin name: Murrelet
  • Other historic names: Xantus’s (when lumped with Scripps’s)
  • Names in other languages: Mexican (Croatian, Norwegian), Baja California (German, Swedish, Turkish), California (Polish), Dark-winged (Slovak), Dark-winged California (Spanish-Mexico)
  • My proposals: Mexican Murrelet, Baja Murrelet

Cassin’s Auklet

  • Meaning of Latin name: Aleutian Auklet
  • Other historic names: Aleutian Auklet (first described before Cassin was born)
  • Meaning of subspecies names: Southern
  • Names in other languages: Aleutian (German), Black (Polish), Ashy/Smoky (Slovak, Turkish), Somber (Spanish), Dark (Spanish-Mexico),
  • My proposals: Pacific Auklet, Ashy Auklet

Sabine’s Gull

  • Meaning of Latin name: Sabine’s Gull
  • Other historic names: Fork-tailed Gull
  • Meaning of subspecies names: Palearctic, Chukhotski, Voznesensky
  • Names in other languages: Fork-tailed (Dutch, Spanish-Cuba, Turkish), Swallow-tailed (Hungarian, Serbian, Slovenian), Split-tailed (Latvian, Lithuanian, Romanian, Spanish-Mexico), Collared (Polish), Tern Gull (Swedish)
  • My proposals: Fork-tailed Gull, Tundra Gull

Bonaparte’s Gull

  • Meaning of Latin name: Philadelphia Gull
  • Other historic names:
  • Names in other languages: Little Black-headed (Dutch, Turkish), Tree (Icelandic, Swedish), Canada Hooded (Norwegian), Canadian (Polish), American (Portuguese), American River (Slovenian), Little/Small (Spanish-Cuba)
  • My proposals: Boreal Gull

Ross’s Gull

  • Meaning of Latin name: Rosy Gull
  • Other historic names:
  • Names in other languages: Rosy (Basque, Catalan, Croatian, Czech, Danish, Finnish, French, German, Icelandic, Lithuanian, Norwegian, Polish, Portuguese, Slovak, Slovenian, Spanish, Swedish, Turkish)
  • My proposals: Rosy Gull

Franklin’s Gull

  • Meaning of Latin name: Aztec Gull (Nahuatl for “gull”)
  • Other historic names:
  • Names in other languages: Prairie (Finish, German, Hungarian, Polish, Portuguese, Slovak, Swedish), Rosy (Spanish-Venezuela), Little (Spanish-Paraguay and Argentina)
  • My proposals: Prairie Gull
Over 95% of the world’s Heermann’s Gulls come from tiny Isla Rasa in the Gulf of California, Mexico.

Heermann’s Gull

  • Meaning of Latin name: Heermann’s Gull
  • Other historic names: White-headed Gull, Belcher Gull
  • Names in other languages: Mexican (Finnish, Spanish), Ashy (Norwegian), Snowy (Polish), Coastal (Slovak), Leaden/Plumbeous (Spanish-Mexico), White-headed (Swedish)
  • My proposals: Isla Rasa Gull, Plumbeous Gull, Mexican Gull, Baja Gull

Forster’s Tern

  • Meaning of Latin name: Forster’s Tern
  • Other historic names:
  • Names in other languages: North American (Czech), Prairie (Danish, Norwegian), Silver (Finnish), Fork-tailed (Haitian), Pond (Hungarian), Black-eared (Polish), Marsh (Slovak, Swedish), American River (Slovenian), Masked (Turkish)
  • My proposals: Marsh Tern

Wilson’s Storm-Petrel

  • Meaning of Latin name: Oceanic Storm-Petrel
  • Other historic names: Yellow-webbed Storm-Petrel
  • Meaning of subspecies names: Exasperating, Chilean
  • Names in other languages: Ordinary/Common (Afrikaans), Yellow-footed (Czech, Polish), Southern (Finnish, Greek), Variegated (German), Oceanic (Icelandic, Spanish-Dom Rep), Brown (Indonesian), Antarctic (Slovenian), Brownish-Gray (Spanish-Uruguay)
  • My proposals: Oceanic Storm-Petrel

Leach’s Storm-Petrel

  • Meaning of Latin name: White-rumped Storm-Petrel
  • Other historic names: Mother Cary’s Chicken
  • Meaning of subspecies names: Chapman’s
  • Names in other languages: Forked/Swallow-tailed (Afrikaans, Hungarian, Italian, Portuguese, Swedish, Turkish), Large (Basque), Northern (Asturian, Catalan, Czech, Latvian, Lithuanian, Spanish), Great (Danish), Storm Fairy (Finnish), White-rumped (French, Haitian), Wave Runner (German), Sea Swallow (Icelandic), Storm Swallow (Norwegian)
  • My proposals: Northern Storm-Petrel

Cory’s Shearwater

  • Meaning of Latin name: Diomedes/White Shearwater
  • Other historic names:
  • Meaning of subspecies names: Northern
  • Names in other languages: Brown (Basque), Ashy (Catalan, French), Gray (Czech), Kuhl’s or Atlantic (Danish), Kuhl’s (Dutch), Macaronesian (Finnish), Sepia (German), Great/Northern (Italian), Yellow-billed (Lithuanian, Norwegian, Polish, Slovenian, Swedish), Mediterranean (Portuguese-Brazil), Fairy (Slovak), Cinderella (Spanish), Large (Spanish-Argentina, Uruguay, Venezuela)
  • My proposals: if split with Scopoli’s, Diomedes/White/Silver Shearwater and Northern Shearwater
I own older bird books that call this both Gray-backed and New Zealand Shearwater.

Buller’s Shearwater

  • Meaning of Latin name: Buller’s Shearwater
  • Other historic names: New Zealand Shearwater, Gray-backed Shearwater, Ashy-black Shearwater
  • Names in other languages: Gray-backed (Czech, German, Norwegian, Polish, Slovak, Spanish, Turkish), Gray (Swedish)
  • My proposals: Gray-backed Shearwater, New Zealand Shearwater, Elegant Shearwater

Audubon’s Shearwater

  • Meaning of Latin name: l’Herminier’s Shearwater
  • Other historic names: Dusky-backed Shearwater
  • Meaning of subspecies names: Miller’s
  • Names in other languages: Seaweed (Icelandic), Equatorial (Polish), Broad-winged (Portuguese), Ocean/Oceanic (Slovak)
  • My proposals: Gulf Stream Shearwater

Brandt’s Cormorant

  • Meaning of Latin name: Paintbrush/Painted/Plumed Cormorant
  • Other historic names: Plumed Cormorant, Green Cormorant
  • Names in other languages: Blue-throated (Croatian, Icelandic, Norwegian, Swedish), Paintbrush (German), Plumed (Polish), Short-tailed (Slovak), Sergeant (Spanish)
  • My proposals: Plumed Cormorant

Cooper’s Hawk

  • Meaning of Latin name: Cooper’s Hawk
  • Other historic names: Blue-backed Hawk, Mexican Hawk
  • Names in other languages: Smooth (Norwegian)
  • My proposals: Woodland Hawk, Blue-backed Hawk, Stealthy Hawk

Harris’s Hawk

  • Meaning of Latin name: Banded Hawk
  • Other historic names: Bay-winged Hawk
  • Meaning of subspecies names: Bay-winged
  • Names in other languages: Desert (Dutch, German), Knight (Finnish), Sand (Icelandic), Cactus (Norwegian, Swedish), Social (Polish), Bay-winged (Portuguese, Slovenian), Four-colored (Slovak), Mixed (Spanish), Red-and-black (Spanish-Mexico), Walking (Spanish-Venezuela)
  • My proposals: Bay-winged Hawk, Cactus Hawk, Social Hawk, Coyote Hawk
Other languages often avoid American honorifics in place of ecology-based names. This bird is known as the Prairie Hawk across much of Europe. In its wintering grounds, it is called the Grasshopper Hawk.

Swainson’s Hawk

  • Meaning of Latin name: Swainson’s Hawk
  • Other historic names: Rocky Mountain Buzzard, Canada Buzzard, Brown Hawk, Sharp-winged Hawk
  • Names in other languages: White-throated (Czech), Prairie (Dutch, Finnish, German, Norwegian, Polish, Portuguese, Slovak, Swedish), Grasshopper (Spanish-Argentina, Chile, Paraguay)
  • My proposals: Prairie Hawk, Plains Hawk, Sharp-winged Hawk

Lewis’s Woodpecker

  • Meaning of Latin name: Lewis’s Woodpecker (previously, Collared Woodpecker)
  • Other historic names:
  • Names in other languages: Blood-faced (German), Crow Woodpecker (Icelandic, Swedish), Flycatching Woodpecker (Norwegian), Pink-bellied (Polish)
  • My proposals: Crow Woodpecker, Wandering Woodpecker

Williamson’s Sapsucker

  • Meaning of Latin name: Shielded Sapsucker
  • Other historic names: Black-breasted Sapsucker, Brown-headed Woodpecker, Round-headed Woodpecker, Brown Woodpecker
  • Meaning of subspecies names: Natalie
  • Names in other languages: Mountain (Dutch), Pine (German, Norwegian), Shielded (Icelandic), Black/Dark-headed (Polish, Swedish), Dark (Spanish), Elegant (Spanish-Mexico)
  • My proposals: Mountain Sapsucker, Montane Sapsucker, Conifer Sapsucker

Nuttall’s Woodpecker

  • Meaning of Latin name: Nuttall’s Woodpecker
  • Other historic names:
  • Names in other languages: California (Norwegian, Polish, Serbian, Spanish-Mexico), Chaparral
  • My proposals: Oak Woodpecker, California Woodpecker

Couch’s Kingbird

  • Meaning of Latin name: Couch’s Kingbird
  • Other historic names:
  • Names in other languages: Texas (Dutch, German, Polish, Russian), Mayan (Norwegian), Whistling (Spanish), Mexican (Swedish, Turkish)
  • My proposals: Whistling Kingbird, Mexican Kingbird, Veracruz Kingbird, Mayan Kingbird
This bird was called a vociferous tyrant by Swainson when Cassin was just 13 years old.

Cassin’s Kingbird

  • Meaning of Latin name: Vociferous/Noisy Kingbird
  • Other historic names: Noisy Kingbird
  • Meaning of subspecies names: Different-winged
  • Names in other languages: Squeaky/Noisy/Screaming (Icelandic, Polish, Spanish), Scrub (Norwegian)
  • My proposals: Vociferous Kingbird

Hammond’s Flycatcher

  • Meaning of Latin name: Hammond’s Flycatcher
  • Other historic names:
  • Names in other languages: Spruce (Dutch, Norwegian, Slovak), Fir (German, Polish),
  • My proposals: Lodgepole Flycatcher, Mountain Flycatcher

Say’s Phoebe

  • Meaning of Latin name: Say’s Phoebe
  • Other historic names: Black-tailed Phoebe
  • Meaning of subspecies names: Peaceful/Tranquil/Quiet, Pale/Pallid
  • Names in other languages: Brown (Finnish, Norwegian), Rufous-bellied (French, Swedish), Cinnamon-bellied (German), Land/Terrestrial (Icelandic), Plain (Slovak), Plains (Spanish)
  • My proposals: Mesa Phoebe, Plains Phoebe, Cinnamon Phoebe

Bell’s Vireo

  • Meaning of Latin name: Bell’s Vireo
  • Other historic names: Greenlet
  • Meaning of subspecies names: Intermediate, Arizona, Least/Tiny
  • Names in other languages: Brown-eyed (German), Floodplain (Slovak), Chaparral (Swedish)
  • My proposals: Riparian Vireo

Hutton’s Vireo

  • Meaning of Latin name: Hutton’s Vireo
  • Other historic names: Dusky Vireo
  • Meaning of subspecies names: Pacific (group), Island, Dusky, Parkes’s, Mountain/Sierra, Unitt’s, Oberholser’s, Connected; Interior (group), Stephens’s, Caroline’s, Peaceful, Mexican, Volcano
  • Names in other languages: Greenish (Icelandic, Polish), Oak (Norwegian), Kinglet Vireo (Spanish-Mexico)
  • My proposals: Oak Vireo, Live Oak Vireo

Cassin’s Vireo

  • Meaning of Latin name: Cassin’s Vireo
  • Other historic names: Solitary Vireo (when lumped with Plumbeous and Blue-headed)
  • Meaning of subspecies names: San Lucas
  • Names in other languages: Ash-green (Icelandic), California (Norwegian), Olive (Polish), Spectacled (Slovak)
  • My proposals: Gray-headed Vireo, Spectacled Vireo
One of the first birds given an honorific name (by a Russian expedition in the late 1700s), I’ve always associated it with mountains. Even when it’s in coastal lowlands, the mountains are never far away.

Steller’s Jay

  • Meaning of Latin name: Steller’s Jay
  • Other historic names: Sierra Jay, Blue-fronted Jay, California Mountain Jay, Crested Jay
  • Meaning of subspecies names: Charlotte, Fronted, Coal, Connecting, Long-crested, Diademed, Phillips, Crowned, Purple, Aztec, Teotepec, Ridgway, Azure, Pleasant
  • Names in other languages: Pine (Norwegian), Diademed (German), Crested (Spanish-Mexico)
  • My proposals: Mountain Jay, Cobalt Jay

Woodhouse’s Scrub-Jay

  • Meaning of Latin name: Woodhouse’s Scrub-Jay
  • Other historic names:
  • Meaning of subspecies names: Nevada, Texas, Gray, Dark-blue, Sumichrast’s, Remote
  • Names in other languages: Juniper (Norwegian), Woodland (Polish), Hooded (Slovak), Necklaced (Spanish-Mexico), Inland (Swedish)
  • My proposals: Juniper Scrub-jay

Clark’s Nutcracker

  • Meaning of Latin name: Columbian Nutcracker
  • Other historic names:
  • Names in other languages: Gray (Dutch, Polish, Swedish), American (Finish, French, Russian, Serbian, Spanish), Pine (German, Norwegian)
  • My proposals: Alpine Nutcracker, Pine Nutcracker

Bewick’s Wren

  • Meaning of Latin name: Bewick’s Wren
  • Other historic names:
  • Meaning of subspecies names: Desert-loving, Obscure/Hidden, Pulich’s, Sada’s, Mexican, Fine-voiced/Melodious, Thicket/Wood-dwelling, Marin, Spot-tailed, White-browed, Beautiful-tailed, Cerros Island, Magdalena, Short-tailed
  • Names in other languages: Gray (Icelandic), Long-tailed (Norwegian, Spanish-Mexico), Mousey (Polish), Garden (Slovak), Black-tailed (Spanish), Thicket (Swedish)
  • My proposals: Thicket Wren, Long-tailed Wren

Bendire’s Thrasher

  • Meaning of Latin name: Bendire’s Thrasher
  • Other historic names:
  • Meaning of subspecies names: White/Glittering, Ruddy
  • Names in other languages: Cactus (Dutch, German, Polish, Slovak), Navajo (Norwegian), Short-billed (Spanish)
  • My proposals: Yucca Thrasher

LeConte’s Thrasher

  • Meaning of Latin name: LeConte’s Thrasher
  • Other historic names: Yuma Thrasher
  • Meaning of subspecies names: McMillan’s, Desert (Vizcaino)
  • Names in other languages: Desert (Dutch, German), Mohave (Norwegian, Swedish), Sand (Polish), Steppe (Slovak), Pale/Pallid (Spanish),
  • My proposals: Yuma Thrasher, Sand Thrasher, Xeric Thrasher
The America’s most northerly solitaire is a juniper specialist.

Townsend’s Solitaire

  • Meaning of Latin name: Townsend’s Solitaire
  • Other historic names:
  • Meaning of subspecies names: Fine-voiced/Melodious
  • Names in other languages: Mountain (Dutch), Squeaky (Icelandic), Gray (Norwegian), Clarinet (Polish), Northern (Spanish, Swedish)
  • My proposals: Juniper Solitaire, Northern Solitaire, Clarinet Solitaire

Bicknell’s Thrush

  • Meaning of Latin name: Bicknell’s Thrush
  • Other historic names:
  • Names in other languages: Newfoundland (Czech), Mountain (Danish), Forest (Norwegian), Wandering (Polish), Brown (Slovak)
  • My proposals: Fir Thrush
Divided into the Russet-backed and Olive-backed groups, Swainson’s Thrush is also known by a variety of names that describe its appearance or habitat.

Swainson’s Thrush

  • Meaning of Latin name: Burnt/Burnished Thrush
  • Other historic names:
  • Meaning of subspecies names: Russet-backed: Phillip’s, Musical; Olive-backed: Hoary, Appalachian, Swainson’s
  • Names in other languages: Dwarf (Croatian, Dutch), Western (Czech), Olive (Danish, French, German, Slovak), Brown Forest (Norwegian), Spectacled (Polish, Portuguese, Spanish-Mexico), Spruce (Slovenian), Boreal/Northern (Spanish-Argentina), Beige (Swedish)
  • My proposals: Boreal Thrush

Sprague’s Pipit

  • Meaning of Latin name: Sprague’s Pipit
  • Other historic names:
  • Names in other languages: Prairie (Danish, Dutch, German, Norwegian, Polish, Slovak, Spanish, Swedish, Turkish)
  • My proposals: Prairie Pipit

Cassin’s Finch

  • Meaning of Latin name: Cassin’s Finch
  • Other historic names: Cassin Purple Finch, Cassin Pine Finch
  • Names in other languages: Rock (Icelandic), Red-crowned (Norwegian), Red-headed (Polish, Slovak), Mountain (Spanish-Mexico)
  • My proposals: Pine Finch, Crimson-crowned Finch

Lawrence’s Goldfinch

  • Meaning of Latin name: Lawrence’s Goldfinch
  • Other historic names:
  • Names in other languages: Masked (Dutch, German), Gray (French, Norwegian), Gorgeous (Polish), Oak (Slovak), Black-faced (Spanish-Mexico), California (Swedish)
  • My proposals: Fiddleneck Goldfinch, Golden-winged Goldfinch, Desert Goldfinch, Oasis Goldfinch

Smith’s Longspur

  • Meaning of Latin name: Painted Longspur
  • Other historic names: Painted Bunting
  • Names in other languages: Pied (Dutch), Golden-bellied (German), Frenzied (Icelandic), Tundra (Norwegian, Swedish), Fawn (Polish), Painted (Slovak)
  • My proposals: Painted Longspur

Botteri’s Sparrow

  • Meaning of Latin name: Botteri’s Sparrow
  • Other historic names:
  • Meaning of subspecies names: Arizona, Texas, Mexican, Goldman’s, Petén, Van Tyne’s, Black-and-chestnut, Volcano
  • Names in other languages: Stripe-backed (German), Straw (Icelandic), Prairie (Polish), Stubble/Grass (Slovak),
  • My proposals: Monsoon Sparrow, Sacaton Sparrow

Cassin’s Sparrow

  • Meaning of Latin name: Cassin’s Sparrow
  • Other historic names:
  • Names in other languages: Apache (Norwegian), Gray (Polish), Meadow (Slovak)
  • My proposals: Skylarking Sparrow, Nomadic Sparrow, Plains Sparrow

Bachman’s Sparrow

  • Meaning of Latin name: Summer Sparrow
  • Other historic names: Pinewoods Sparrow
  • Meaning of subspecies names: Bachman’s, Illinois
  • Names in other languages: Pine (Dutch, French, German), Palmetto (Norwegian), Sharp-tailed (Polish)
  • My proposals: Pinewoods Sparrow, Summer Sparrow
Brewer’s Sparrow maps so well onto traditional Shoshone lands that I looked up the word in Shoshone, which translates to “sage bird” or “sage sparrow”. This would be a great English name, though it would cause confusion with the other species formerly known by that name.

Brewer’s Sparrow

  • Meaning of Latin name: Brewer’s Sparrow
  • Other historic names: Pale Sparrow
  • Meaning of subspecies names: Taverner’s (aka Timberline)
  • Names in other languages: Pale (German), Shoshone (Norwegian), Bright-bellied (Polish), Sage (Shoshone)
  • My proposals: Dawn Sparrow, Trilling Sparrow, Shoshone Sparrow

Harris’s Sparrow

  • Meaning of Latin name: Mourning/Plaintive Sparrow
  • Other historic names:
  • Names in other languages: Black-crowned (Dutch), Eskimo (Finnish), Black-faced (French, Polish, Slovak), Spruce (Norwegian), Canada (Swedish)
  • My proposals: Mourning Sparrow, Treeline Sparrow

Bell’s Sparrow

  • Meaning of Latin name: Bell’s Sparrow
  • Other historic names: Sage Sparrow when lumped with Sagebrush Sparrow
  • Meaning of subspecies names: Gray/Hoary, San Clemente Island, Ashy
  • Names in other languages: Sage (German), Chaparral (Norwegian), California (Spanish-Mexico)
  • My proposals: Chaparral Sparrow

LeConte’s Sparrow

  • Meaning of Latin name: LeConte’s Sparrow
  • Other historic names:
  • Names in other languages: Gray-eared (Norwegian), Striped Marsh (Polish), Meadow (Slovak)
  • My proposals: Meadow Sparrow

Nelson’s Sparrow

  • Meaning of Latin name: Nelson’s Sparrow
  • Other historic names: Sharp-tailed Sparrow (when lumped with Saltmarsh Sparrow)
  • Meaning of subspecies names: Other, Streak-bellied
  • Names in other languages: Needle-tailed (Norwegian), Marsh (Polish), Wetland (Slovak)
  • My proposals: Marsh Sparrow

Baird’s Sparrow

  • Meaning of Latin name: Baird’s Sparrow
  • Other historic names:
  • Names in other languages: Dakota (Norwegian), Meadow (Polish), Solitary/Reclusive (Slovak), Prairie (Swedish)
  • My proposals: Prairie Sparrow, Buffalo Sparrow, Dakota Sparrow

Henslow’s Sparrow

  • Meaning of Latin name: Henslow’s Sparrow
  • Other historic names:
  • Meaning of subspecies names: Whispering
  • Names in other languages: Red-winged Swamp (Polish), Weed (Slovak)
  • My proposals: Tallgrass Sparrow

Lincoln’s Sparrow

  • Meaning of Latin name: Lincoln’s Sparrow
  • Other historic names: Forbush Sparrow
  • Meaning of subspecies names: Slender/Elegant, High-dweller/Mountain
  • Names in other languages: Streaked/Striped (Czech, Danish), Cane-browed (Haitian), Breast (Icelandic), Gray-browed (Norwegian), Gray-breasted Fawn (Polish), Migratory (Spanish-Venezuela)
  • My proposals: Fawn Sparrow, Bog Sparrow
The masked Abert’s Towhee is another Southwest mesquite specialist.

Abert’s Towhee

  • Meaning of Latin name: Abert’s Towhee
  • Other historic names:
  • Meaning of subspecies names: Thicket, Vorhies’s
  • Names in other languages: Black-chinned (Dutch, German), Masked (Norwegian, Spanish-Mexico), Black-faced (Polish, Slovak), Arizona (Swedish)
  • My proposals: Mesquite Towhee, Bosque Towhee, Masked Towhee, Arizona Towhee

Bullock’s Oriole

  • Meaning of Latin name: Bullock’s Oriole
  • Other historic names: Northern (when lumped with Baltimore), Western Oriole
  • Meaning of subspecies names: Short
  • Names in other languages: Turnip (Icelandic), Golden-browed (Norwegian), Orange-browed (Spanish-Mexico), White-winged (Slovak)
  • My proposals: Western Oriole, Cottonwood Oriole

Audubon’s Oriole

  • Meaning of Latin name: Step-tailed Oriole
  • Other historic names: Black-headed Oriole
  • Meaning of subspecies names: Audubon’s, Nayarit, Dickey’s
  • Names in other languages: Black-headed (Dutch, German, Polish, Slovak), Citrine/Lemon (Norwegian), Black-hooded (Spanish-Mexico),
  • My proposals: Citrine Oriole

Scott’s Oriole

  • Meaning of Latin name: Paris’s Oriole
  • Other historic names:
  • Names in other languages: Gold-green (French), California (German), Yucca (Norwegian), Prickly Pear (Spanish-Mexico), Black-headed (Slovak)
  • My proposals: Yucca Oriole

Brewer’s Blackbird

  • Meaning of Latin name: Blue/Purple-headed Blackbird
  • Other historic names: Satin Bird, Glossy Blackbird, Western Blackbird
  • Names in other languages: Field (Finnish), Purple (German, Polish, Slovak), Smooth/Satin (Icelandic), Purple-headed (Norwegian), Yellow-eyed (Spanish-Mexico), Prairie (Swedish)
  • My proposals: Purplish Blackbird, Purple-headed Blackbird, Satin Blackbird

Swainson’s Warbler

  • Meaning of Latin name: Swainson’s Warbler
  • Other historic names:
  • Names in other languages: Sharp-beaked (Haitian), Cane (Icelandic, Polish), Brown (Norwegian), Long-billed (Slovak), Brown-capped (Spanish-Mexico), Plain (Spanish-Venezuela)
  • My proposals: Cane Warbler, Palmetto Warbler, Bayou Warbler

Lucy’s Warbler

  • Meaning of Latin name: Lucy’s Warbler
  • Other historic names: Mesquite Warbler, Desert Warbler
  • Names in other languages: Red/Rufous-rumped (German, Spanish-Mexico, Swedish), Plain (Icelandic), Mesquite (Norwegian), Rusty (Polish), Little (Slovak)
  • My proposals: Mesquite Warbler
Originally named Tolmie’s Warbler, and called that in some older bird books, it carries two honorifics, one in English and one in Latin. Others call it by its appearance or preference for riparian thickets.

Virginia’s Warbler

  • Meaning of Latin name: Virginia’s Warbler
  • Other historic names:
  • Names in other languages: Yellow-vented (German), Pine (Norwegian), Ravine (Slovak)
  • My proposals: Juniper Warbler, Great Basin Warbler

MacGillivray’s Warbler

  • Meaning of Latin name: Tolmie’s Warbler
  • Other historic names: Tolmie’s Warbler
  • Names in other languages: Mourning (Dutch), Bush/Shrub (French), Thicket/Copse (German, Norwegian), Earth/Soil (Icelandic), Lemon (Polish), Scrub (Slovak), Tolmie’s (Spanish), Black-lored (Spanish-Mexico), Gray-headed (Swedish)
  • My proposals: Thicket Warbler, Riparian Warbler, Riverine Warbler, Brook Warbler

Kirtland’s Warbler

  • Meaning of Latin name: Kirtland’s Warbler
  • Other historic names:
  • Names in other languages: Michigan (German), Firefield (Norwegian), Spotted (Slovak)
  • My proposals: Jack Pine Warbler, Wildfire Warbler

Blackburnian Warbler

  • Meaning of Latin name: Dusky or Dark Warbler
  • Other historic names:
  • Names in other languages: Hemlock (Czech, Norwegian), Fire (Danish, Spanish-Puerto Rico), Spruce (Dutch, German), Orange-throated (French, Spanish), Little Flamboyant (Haitian), Orange-crowned (Hungarian), Glossy/Glowing (Icelandic), Red-breasted (Lithuanian), Red Forest (Polish), Firecracker (Portuguese), Orange-streaked (Swedish)
  • My proposals: Flamboyant Warbler, Flame-faced Warbler

Grace’s Warbler

  • Meaning of Latin name: Grace’s Warbler
  • Other historic names:
  • Meaning of subspecies names: Yaeger’s, Remote, Beautiful
  • Names in other languages: Arizona (German), Ponderosa (Norwegian), Yellow-throated (Polish), Yellow-breasted (Slovak), Yellow-browed (Spanish-Mexico), Gray-headed (Swedish)
  • My proposals: Yellow-fronted Warbler, Pine-oak Warbler

Townsend’s Warbler

  • Meaning of Latin name: Townsend’s Warbler
  • Other historic names:
  • Names in other languages: Tree (Icelandic), Spruce (Norwegian), Black Forest (Polish)
  • My proposals: Evergreen Warbler
Western field guides thru the 1950s called it the Pileolated Warbler. Its Latin name means Tiny Warbler. Wilson himself called it the Green Black-capped Flycatcher.

Wilson’s Warbler

  • Meaning of Latin name: Little or Tiny Warbler
  • Other historic names: Pileolated Warbler, Black-capped Yellow Warbler, Green Black-cap Warbler, Green Black-capped Flycatcher
  • Meaning of subspecies names: Pileolated, Golden
  • Names in other languages: Black-crowned (Swedish, Spanish-Mexico), Black-capped (Portugese)
  • My proposals: Brilliant Warbler, Golden-green Warbler

My other blog posts about bird names for birds:

Bird names matter: Top ornithologists and organizations endorse name changes for all species named after people

Honorific bird names facts and figures

Erasure, white fragility, and the verbal monuments of bird names: Should we hold people in the past accountable to present-day mores?

Reflections of a Native birder: The one Indian killer bird name I really have trouble with

This golden-winged gem, known for its erratic wanderings, can often by found at desert oases and wherever fiddleneck is blooming.

The maddening truth: Feeding crows and jays harms other birds

Backyard bird feeders bring nature close to people, increase appreciation for the natural world, and, in winter, help birds survive. But research also documents some adverse effects, such as the potential to spread avian diseases and to inflate the population of nest predators. There’s a lot of attention on the former, but the latter issue probably does a lot more harm.  

Close to half of all bird nests fail due to predation. Corvids (ravens, crows, jays, and magpies) play a big part in that; they are among the most voracious nest predators, taking other birds’ eggs and chicks. Squirrels and rats are also major nest predators. Open cup nesters are especially vulnerable.

Crows and jays are especially fond of peanuts. Feeding them may depress other bird populations.

Corvids are part of the natural ecosystem, but the problem goes beyond “natural” because many corvid populations are artificially higher due to anthropogenic food subsidies – human garbage, bird feeders, scraps, etc. In short, corvids are often what biologists call human-subsidized predators. Millions of restoration dollars have been spent trying to protect declining species from corvids (e.g., Marbled Murrelet, Least Tern, Snowy Plover, Piping Plover, and Desert Tortoise). Additionally, local populations of otherwise common species are known to be at risk from corvids (e.g. Common Murre, Red-capped Plover). And research shows they can depress bird populations in residential neighborhoods.

The Research

Sign from Big Basin State Park. Corvid-control measures may include removal (killing or transferring elsewhere), camper education, improved food storage, and food waste management and garbage control, among other measures. There is a vast literature on the topic.

By providing food, humans have a remarkable ability to inflate corvid populations. Brunk et al (2021) examined efforts to reduce Steller’s Jay densities at campgrounds in Big Basin State Park in California in order to protect endangered Marbled Murrelets. Jay densities within the campgrounds were nine times higher than in the surrounding forest. Previous research documented that the Steller’s Jay juvenile survival rate in the campgrounds was over 90%, possibly the highest figure ever recorded for a bird; 50% is more typical. After the installation of new garbage cans, food lockers, as well as extensive camper education, the jays disbursed and densities fell to natural levels. I’m proud to have been a part of that project.

There is a long list of papers that show the depressing impact that high numbers of jays and crows can have on the productivity and populations of other birds. Here are a few examples focusing on songbirds:

Jokimäki et al (2020) looked at nest predation rates in nine European cities, finding that cats and corvids had a significant impact on other birds’ nest success in urban and suburban areas.

Hanmer et al (2017) experimented with artificial thrush nests with quail eggs placed in a natural context but in the vicinity of bird feeders that were offering peanuts. Nests near active feeders were far more likely to be depredated than nests that were far away from peanut feeders. The predators were jays, magpies and squirrels.

Malpass et al (2017) conducted an experiment in seven neighborhoods in Ohio, adding bird feeders during the breeding season to some areas. The neighborhoods with the most feeders had triple the numbers of American Crows and Brown-headed Cowbirds compared to the neighborhoods with the least feeders.  American Robin nest success fell to just 1% in the high-feeder neighborhoods, compared to 34% in the areas with the fewest feeders. Northern Cardinals, perhaps because their nests are generally more hidden, managed to avoid these impacts.

In the Santa Cruz Mountains of California, eggs painted to look like Marbled Murrelet eggs are injected with a chemical that causes jays to vomit. This has trained some jays to avoid them.

Jokimäki and Huhta (2000) looked at bird assemblages across urban, suburban, and natural areas in Finland. They found a dramatically higher nest predation rate in the managed urban parks (53 to 92%) compared to more wild suburban parks (22 to 67%). Additionally, most ground nesting species simply avoided the urban areas. Crows and jays were listed among the primary nest predators.

Stoate and Szczur (1994) reported that corvid removal led to dramatic improvement in the hatching success of thrushes and Chaffinch. Some ground-nesting and thicket-nesting species (Dunnock, Yellowhammer, etc) were unaffected by corvids.

Slagsvold (1980) found that Fieldfare populations (the Scandinavian counterpart to the American Robin) doubled after the removal of Carrion Crows (the counterpart to the American Crow). Smaller songbirds also sought protection and nested near Fieldfares. Many songbirds based nest site decisions on the presence or absence of crows.

There are several meta-analyses, studies of studies, that try to summarize the big picture. Most of these include a wide array of avian and mammalian predators—and most focus on ground-nesting shorebirds and gamebirds, where conservation and hunting interests fuel research funding.

Hanmer et al (2017) examined the fate of artificial nests placed 5 and 10 meters away from feeders with peanuts, feeders with peanuts and a protective cage guard to exclude predators, and empty feeders. Approximately 90% of nests near empty feeders survived the first day, and 50% remained a week later. Near active peanut feeders, these numbers fell to 50% and just 10%. Guarded feeders only slightly reduced the impact.

Cote and Sutherland (1997) is typical. It reviews 29 studies, focusing on avian (crows, gulls, grackles) and mammalian (foxes, skunk, marten) nest predation on gamebirds (pheasants, quail, etc) and some songbirds. Removing predators had a large positive effect on the prey species’ productivity and post-breeding population.

It is important to add that not all studies have found a link between corvids and reduced densities of other birds. This seems to be truer in rural contexts. Furthermore, impacts seem to be species-specific. I can imagine, for example, that chickadees and nuthatches, which nest in small cavities, are relatively protected from jay and crow nest predation.

Finally, there is Madden et al (2015), a meta-analysis focusing exclusively on corvids, which caused some confusion. It focused mostly on impacts to gamebirds and did not include jays. It is curious because its summaries and conclusions do not match the data they present. Based on their data, Madden could have concluded with this:

“The presence of crows had a negative impact on other bird species’ productivity in 66% of cases. In 10% of cases, a decline in abundance was also detected. These results suggest that, in certain contexts and for many species, large crow populations may create population sinks or actual declines in the populations of other birds.”

That would have been consistent with other studies, but the paper didn’t end that way. Instead, it summarized the data in ways to bury important results, failed to include some well-known cases involving endangered species, and concluded with this head-scratching statement:

“Our review shows that although there is no consistent pattern with regard to corvid impacts on other bird species, the most commonly reported effect is that corvids have no negative impact on prey species abundance or productivity. When combining experimental and correlative studies (326 cases), most cases (81%, n=264) showed no negative influence of corvids on either abundance or productivity of birds…”

“Most commonly” meant more than 50%. Because they lumped magpies with crows, and lumped abundance with productivity, they were able to say this (barely). I am astonished this paper passed thru peer review with this sweeping, and deceptive, summary intact. Some backyard birders, in defense of laying out a smorgasbord of peanuts on their back patio, have cited this paper on social media.

There’s a lot more I can say about this paper, but suffice it to say their own numbers (see Table 4) imply that two-thirds of studies involving crows found significant impacts to other species’ productivity.

Conclusion: No peanuts, and use caution in the breeding season

Make no mistake—bird-feeders in winter are associated with increased bird survival. There are lots of papers about that. I feed birds in winter (but no peanuts!). In the spring and summer, however, when my juncos and sparrows have departed, those same feeders disproportionately attract jays, crows, and squirrels, as well as House Sparrows, Eurasian Starlings, and Brown-headed Cowbirds. It’s no wonder that open cup nesters have a tough time. In the summer, I maintain hummingbird feeders and have a little pond and fountain that attracts bathing warblers.

Bird feeding in spring and summer, and especially offering peanuts which disproportionately attract crows and jays, likely depresses the populations of other songbirds in the vicinity. This is probably a big reason why many suburban neighborhoods can be largely devoid of cup nesters (e.g. warblers, vireos, flycatchers) while still having cavity and thicket nesters (e.g. chickadees, nuthatches, wrens, towhees).

A good sentinel species may be the American Robin. If your neighborhood is devoid of breeding robins, and especially fresh juvenile robins, it may be due to excessive numbers of jays or crows.

References

Benmazouz et al. 2021. Corvids in urban environments: A systematic global literature review. Animals.

Brunk et al. 2021. Reducing anthropogenic subsidies can curb density of overabundant predators in protected areas. Biological Conservation.

Cote and Sutherland. 1997. The effectiveness of removing predators to protect bird populations. Conservation Biology.

Hanmer et al. 2017. Provision of supplementary food for wild birds may increase the risk of local nest predation. Ibis.

Jokimäki et al. 2020. Land-sharing vs. land-sparing urban development modulate predator–prey interactions in Europe. Ecological Applications.

Jokimäki and Huhta. 2000. Artificial nest predation and abundance of birds along an urban gradient. The Condor.

Madden et al. 2015. A review of the impact of corvids on bird productivity and abundance. Ibis.

Malpass et al. 2017. Species-dependent effects of bird feeders on nest predators and nest survival of urban American Robins and Northern Cardinals. The Condor.

Shutt and Lees. 2021. Killing with kindness: Does widespread generalised provisioning of wildlife help or hinder biodiversity conservation efforts? Biological Conservation.

Slagsvold. 1980. Habitat selection in birds: on the presence of other birds species with special regard to Turdus pilaris. Journal of Animal Ecology.

Stoate and Szczur. 1994. Game management and songbirds. The Game Conservancy Review of 1993.

In 2021, Shutt and Lees reminded us that we (humans and jays and warblers) are all connected:  “Generalised provisioning is enthusiastically promoted by many conservation organisations as a means to foster connection with nature and help wildlife. However, such a vast input of additional resources into the environment must have diverse, ecosystem-wide consequences. Direct effects…  are generally positive in leading to increased survival, productivity and hence population growth. However, we argue that the wider implications for the recipients’ non-provisioned competitors, prey and predators are underappreciated and have the potential to generate pervasive negative impacts for biodiversity.”

Northward expansion of Northern Cardinal, Carolina Wren, Tufted Titmouse, and Red-bellied Woodpecker

A number of recent academic papers have described northward shifts of bird species in both North America and Europe, driven by climate change. These papers usually present aggregated results from dozens of species; they rarely provide details for any specific species. These maps are intended to offer that.

While there are tremendous species-specific differences, non-migratory resident birds (such as Northern Cardinal, Carolina Wren, Tufted Titmouse, and Red-bellied Woodpecker) appear to be the most adaptable and have expanded their ranges the most. This seems to be primarily driven by warmer winters and, for some species, is further augmented by bird feeders.

I created these maps using eBird, so the usual caveats apply– they don’t necessarily include all records (though many historical out-of-range records are indeed included), and eBird reporting, which became widespread only after 2010, continues to increase dramatically each year. To draw the lines, my intent was to capture the primary range area — and more — but I deliberately excluded the furthest ten to fifteen outliers for each line.

CLICK TO ENLARGE GRAPHICS

Northern Cardinals (once called Kentucky Cardinals) have been expanding north for decades, but have increased their rate.
Carolina Wren is a classic example of a species knocked back by harsh winters, finding some refuge around bird feeders, and then continuing to expand in warmer winters. See a graph of this at my previous post here.
Like many species, Tufted Titmouse has especially expanded northeast up the St. Lawrence River corridor.
To get a feel for what this expansion actually looks like in one place, see the graphs below from Christmas Bird Counts. Similar graphs could be made for all of these species.

For some examples of western species expanding north from California and southern Oregon into the Pacific Northwest, see this post: The invasion of the Pacific Northwest: California’s birds expand north with warmer winters.

I invite you to join the Facebook group dedicated to this topic: Birds and Climate Change.

Two of the academic papers that report climate-driven range expansions in eastern North America are listed below, along with their abstracts.

Prince, K. and B. Zuckerberg. 2016. Climate change in our backyards: the reshuffling of North America’s winter bird communities. Global Change Biology 21(2): 572-585.

Much of the recent changes in North American climate have occurred during the winter months, and as result, overwintering birds represent important sentinels of anthropogenic climate change. While there is mounting evidence that bird populations are responding to a warming climate (e.g., poleward shifts) questions remain as to whether these species-specific responses are resulting in community-wide changes. Here, we test the hypothesis that a changing winter climate should favor the formation of winter bird communities dominated by warm-adapted species. To do this, we quantified changes in community composition using a functional index–the Community Temperature Index (CTI)–which measures the balance between low- and high-temperature dwelling species in a community. Using data from Project FeederWatch, an international citizen science program, we quantified spatiotemporal changes in winter bird communities (n = 38 bird species) across eastern North America and tested the influence of changes in winter minimum temperature over a 22-year period. We implemented a jackknife analysis to identify those species most influential in driving changes at the community level and the population dynamics (e.g., extinction or colonization) responsible for these community changes. Since 1990, we found that the winter bird community structure has changed with communities increasingly composed of warm-adapted species. This reshuffling of winter bird communities was strongest in southerly latitudes and driven primarily by local increases in abundance and regional patterns of colonization by southerly birds. CTI tracked patterns of changing winter temperature at different temporal scales ranging from 1 to 35 years. We conclude that a shifting winter climate has provided an opportunity for smaller, southerly distributed species to colonize new regions and promote the formation of unique winter bird assemblages throughout eastern North America.

Saunders et al. 2022. Unraveling a century of global change impacts on winter bird distributions in the eastern United States. Global Change Biology

One of the most pressing questions in ecology and conservation centers on disentangling the relative impacts of concurrent global change drivers, climate and land-use/land-cover (LULC), on biodiversity. Yet studies that evaluate the effects of both drivers on species’ winter distributions remain scarce, hampering our ability to develop full-annual-cycle conservation strategies. Additionally, understanding how groups of species differentially respond to climate versus LULC change is vital for efforts to enhance bird community resilience to future environmental change. We analyzed long-term changes in winter occurrence of 89 species across nine bird groups over a 90-year period within the eastern United States using Audubon Christmas Bird Count (CBC) data. We estimated variation in occurrence probability of each group as a function of spatial and temporal variation in winter climate (minimum temperature, cumulative precipitation) and LULC (proportion of group-specific and anthropogenic habitats within CBC circle). We reveal that spatial variation in bird occurrence probability was consistently explained by climate across all nine species groups. Conversely, LULC change explained more than twice the temporal variation (i.e., decadal changes) in bird occurrence probability than climate change on average across groups. This pattern was largely driven by habitat-constrained species (e.g., grassland birds, waterbirds), whereas decadal changes in occurrence probabilities of habitat-unconstrained species (e.g., forest passerines, mixed habitat birds) were equally explained by both climate and LULC changes over the last century. We conclude that climate has generally governed the winter occurrence of avifauna in space and time, while LULC change has played a pivotal role in driving distributional dynamics of species with limited and declining habitat availability. Effective land management will be critical for improving species’ resilience to climate change, especially during a season of relative resource scarcity and critical energetic trade-offs.

Carolina Wren + Climate Change vs the Polar Vortex

Like so many species, the Carolina Wren is expanding northward. And, like many of those species, this expansion started decades ago, before any measurable climate change, but has exploded in the past decades with climate change.

This phenomenon is most obvious – and even dramatic – among non-migratory species and short-distance migrants. The same thing is happening in the West (e.g. Anna’s Hummingbird, Turkey Vulture, Red-shouldered Hawk, Great Egret, California Scrub-Jay, Black Phoebe, Townsend’s Warbler, and others).

The Carolina Wren has been expanding north since the 1800s due to habitat recovery after deforestation (Haggerty and Morton, 2020 – the Birds of North America (BNA) species account). What makes the recent Carolina Wren data so interesting is that we can clearly see, in its expansion into Canada, its battle with winter weather conditions.

The raw number of Carolina Wrens reported on Christmas Bird Counts in Canada. Over 95% of these come from southern Ontario. The cold waves marked on the graph were particularly record-breaking and long-lasting.

The species is known for “decimation… by severe winter conditions” (BNA) at the northern limits of its range. The same account notes that “severe winters have apparently been infrequent enough during the 20th century to allow populations to expand and move northward.” Indeed, one of the key conclusions of an analysis of climate change in southern Ontario was that there has been “a decrease in the frequency of cold temperature extremes”.  While the wren is aided against cold snaps by bird feeders, the climate trend, at least in Canada, is in its favor. The report noted an overall average increase of 1.5C.

eBird abundance map. The Carolina Wren has primarily been a species of edge habitat associated with moist southern forests.

As the wren expanded, certain record-breaking and persistent cold waves knocked the population back, where it restarted. It’s also clear that it is restarting from a higher position each time, thus building its numbers and continuing its expansion.

The cold snaps denoted on the graph were particularly severe in southern Ontario. A more detailed look at weather data may reveal a more complicated pattern and even greater correlation to warmer winters.

Predicted range changes for Carolina Wren by National Audubon under 1.5C scenario. This map is fairly accurate as the bird continues to colonize the St. Lawrence River corridor.
eBird map for December 2021 showing colonization from Toronto to Ottawa and Montreal and nearly to Quebec City.
A Carolina Wren fluffed up against the cold. Pic from National Audubon website.