Tag Archives: eBird

eBird Trends maps reveal dramatic northward range shifts in Eastern species

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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.

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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 Sciences, 117(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.

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

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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

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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!

Carolina Wren + Climate Change vs the Polar Vortex

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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.

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

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At the American Ornithological Society (AOS) Congress on English Bird Names on April 16, 2021, a host of prominent organizations and individuals endorsed “bird names for birds”, a widespread effort to rename eponymous or honorific species names with more descriptive names, focusing on their physical or ecological attributes. For example, Wilson’s Warbler could become Black-capped Warbler, Townsend’s Solitaire might become Northern or Juniper Solitaire, and Kittlitz’s Murrelet would probably be re-named Glacier Murrelet.

MacGillivray’s Warbler was named by John James Audubon after his friend, William MacGillivray, a Scottish ornithologist who never came to America. Audubon also coined its Latin specific, tolmiei, to honor William Fraser Tolmie, a Scottish employee of Hudson’s Bay Company based at Fort Nisqually during the period of Native removal. Scientific, or Latin names, are subject to international rules and are not the focus of this process.

While specific new names have not yet been chosen, representatives of the American Birding Association (ABA), National Audubon Society, as well as David Sibley and Kenn Kaufmann, all heartily endorsed developing a process to make the changes, noting that new names would engage a larger audience, contribute to greater equity and inclusivity among birders and the interested public, and could aid in public communication and conservation efforts.

The effort has grown out of the national reckoning on racial equality in the aftermath of the George Floyd killing. Movements to change names are underway with regard to parks, mountains, streets, other wildlife, and even rock-climbing routes. Current names generally go back to the eighteenth and nineteenth centuries during European expansion across North America and recall an era of conquest, when species and landforms were “discovered” – and some named after the individual who documented them, or after their friends and colleagues.

An FAQ, full list of the panelists, and a video of the Congress can be found at the AOS English Bird Names website. The direct link to the video is here.

Sibley commented that, the more he learns about the names, “the more they cast a shadow over the bird” and “the name doesn’t mean just the bird anymore. They have baggage.” Out of respect for people and the birds, they “should not have to carry a reminder of our own fraught history.” Choosing between stability and respect, Sibley stated “I choose respect.”

Name changes over social justice concerns began last year when McCown’s Longpsur was changed to Thick-billed Longspur, after widespread outcry because McCown was a Confederate general and involved in the ethnic cleansing of Native Americans. A proposal in 2018 for that name change was roundly rejected. 

Name changes for these reasons are not new; most birders can probably recall the switch from Oldsquaw to Long-tailed Duck in 2000. At that time, the American Ornithologists’ Union, the precursor to the AOS, asserted that the name change was not for reasons of “political correctness” but merely to conform with usage elsewhere.

The Bird Names for Birds website includes bios of various people memorialized with bird names. For example, Townsend (of the solitaire, warbler, and storm-pretrel) collected Native skulls for his friend Samuel Morton, author of Crania Americana. The November 2020 issue of Birding magazine focused on name changes, with a strong endorsement by ABA President Jeffrey Gordon and a longer article providing historical background. It is available here for ABA members.

Bird Names for Birds, a group of interested birders, was instrumental in reaching out to the larger organizations to participate in the congress. In their words, “Eponyms (a person after whom a discovery, invention, place, etc., is named or thought to be named) and honorific common bird names (a name given to something in honor of a person) are problematic because they perpetuate colonialism and the racism associated with it. The names that these birds currently have—for example, Bachman’s Sparrow—represent and remember people (mainly white men) who often have objectively horrible pasts and do not uphold the morals and standards the bird community should memorialize.” They describe such names as “verbal statues” that should be removed.

Jordan Rutter of Bird Names for Birds argued that, when reaching out to the public to protect an endangered sparrow, Bachman’s Sparrow has much less appeal than an alternative name rooted in local ecology that the public could identify with. Kaufmann pointed out that Bachmann was a pro-slavery white supremacist and that the species was formerly known as the Pinewoods Sparrow.

In the AOS’s own language, “The Community Congress opens the discussion on the complex issues around eponymous English Bird Names…. The specific aim of the Community Congress is to provide an opportunity for a broad range of stakeholders from the birding and ornithological community to share their viewpoints, including challenges and opportunities from their perspectives, to best inform future next steps to address the issue of naming birds after people.”

The AOS Congress on English Bird Names was superbly moderated by José González, providing a model for the process ahead.

Keepers of various ornithological databases also participated in the Congress, including representatives for eBird, Christmas Bird Counts, Breeding Bird Surveys, and the Bird Banding Laboratory. While noting potential complications with name changes (and changes in four-letter banding codes), they all agreed the hurdles were not insurmountable. Indeed, name changes, as well as taxonomic lumps and splits, occur every year, with name changes being the simplest of the three to address in data management. eBird currently supports bird names in 47 languages, including 14 different versions of English. Where Americans see Black-bellied Plover, Brits see Grey Plover.

Marshall Iliff of eBird pointed out that the effort is also an opportunity to clean up old taxonomic messes, pointing out that Audubon’s Shearwater has been used for eleven different combinations of nine different taxa. In this case, he said, fresh names for specific taxa will provide clarity, not confusion. He embraced a worldwide effort to “dig into the essence of each species” to “find inspired and appropriate names.”

For now, the effort will be limited to primary eponymous English bird names. The effort will not include secondary names (e.g., American Crow, named after the continent, which was named after Amerigo Vespucci). Other problematic names, such as Flesh-footed Shearwater for a bird with pink feet, were not discussed.

Many suggested using Native names for species, though most stated this could be challenging because 1) names from Native languages may have been lost, or 2) most bird species’ ranges span multiple historic aboriginal territories and languages, creating a conundrum over which indigenous word to use. The exception to this is Hawaii, where indigenous names are already in widespread use. Among mammals, moose, raccoon, and skunk are all derived from Algonquian.

Does Lawrence’s Goldfinch deserve a better name?

Looking at Version 8.0.8 (March 12, 2021) of the ABA Checklist, 115 of the 1,123 species, or a little over 10%, are named after people. Of these, 2 (Bishop’s Oo and Bachman’s Warbler) are considered extinct, and 20 others are Code 4 or 5, meaning they occur extremely rarely in the ABA area (though three of these are regular in Mexico, within the AOS area). The remaining 93 are all Code 1, 2, or 3, and can be expected to be seen in the ABA area regularly.

Here are the 113 non-extinct species from the ABA Checklist.

Ross’s Goose

Steller’s Eider

Stejneger’s Scoter

Barrow’s Goldeneye

Gambel’s Quail

Erckel’s Francolin

Clark’s Grebe

Vaux’s Swift

Rivoli’s Hummingbird

Anna’s Hummingbird

Costa’s Hummingbird

Allen’s Hummingbird

Xantus’s Hummingbird

Ridgway’s Rail

Wilson’s Plover

Temminck’s Stint

Baird’s Sandpiper

Wilson’s Snipe

Wilson’s Phalarope

Kittlitz’s Murrelet

Scripps’s Murrelet

Craveri’s Murrelet

Cassin’s Auklet

Sabine’s Gull

Bonaparte’s Gull

Ross’s Gull

Franklin’s Gull

Pallas’s Gull

Belcher’s Gull

Heermann’s Gull

Forster’s Tern

Salvin’s Albatross

Wilson’s Storm-Petrel

Swinhoe’s Storm-Petrel

Leach’s Storm-Petrel

Townsend’s Storm-Petrel

Tristram’s Storm-Petrel

Murphy’s Petrel

Fea’s Petrel

Zino’s Petrel

Cook’s Petrel

Stejneger’s Petrel

Bulwer’s Petrel

Jouanin’s Petrel

Parkinson’s Petrel

Cory’s Shearwater

Buller’s Shearwater

Newell’s Shearwater

Bryan’s Shearwater

Audubon’s Shearwater

Brandt’s Cormorant

Cooper’s Hawk

Steller’s Sea-Eagle

Harris’s Hawk

Swainson’s Hawk

Lewis’s Woodpecker

Williamson’s Sapsucker

Nuttall’s Woodpecker

Nutting’s Flycatcher

La Sagra’s Flycatcher

Couch’s Kingbird

Cassin’s Kingbird

Hammond’s Flycatcher

Say’s Phoebe

Bell’s Vireo

Hutton’s Vireo

Cassin’s Vireo

Steller’s Jay

Woodhouse’s Scrub-Jay

Clark’s Nutcracker

Bewick’s Wren

Pallas’s Leaf Warbler

Blyth’s Reed Warbler

Pallas’s Grasshopper-Warbler

Middendorff’s Grasshopper-Warbler

Townsend’s Solitaire

Bicknell’s Thrush

Swainson’s Thrush

Bendire’s Thrasher

LeConte’s Thrasher

Sprague’s Pipit

Pallas’s Rosefinch

Cassin’s Finch

Lawrence’s Goldfinch

Smith’s Longspur

McKay’s Bunting

Pallas’s Bunting

Botteri’s Sparrow

Cassin’s Sparrow

Bachman’s Sparrow

Brewer’s Sparrow

Worthen’s Sparrow

Harris’s Sparrow

Bell’s Sparrow

LeConte’s Sparrow

Nelson’s Sparrow

Baird’s Sparrow

Henslow’s Sparrow

Lincoln’s Sparrow

Abert’s Towhee

Bullock’s Oriole

Audubon’s Oriole

Scott’s Oriole

Brewer’s Blackbird

Swainson’s Warbler

Lucy’s Warbler

Virginia’s Warbler

MacGillivray’s Warbler

Kirtland’s Warbler

Grace’s Warbler

Townsend’s Warbler

Wilson’s Warbler

Morelet’s Seedeater

There are also several hybrids (e.g. Brewster’s and Lawrence’s Warblers), prominent subspecies (e.g. Thayer’s Gull and Audubon’s Warbler), and superspecies (e.g. Traill’s Flycatcher) that are used in some databases. It is not clear if these will be addressed at this time.

whit! Sorting out the call notes of western Empidonax flycatchers

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After a flurry of migrant Empidonax flycatchers this April in California, a number of us engaged in a discussion about their whit! call notes. Specifically, could we tell Willow from Dusky from Gray just by the whit? Personally, I’m not there yet. I usually only hear them a few times a year, which is insufficient experience, and I suspect there’s individual variation as well as the tricks that wind, humidity, and distance play on sound. But what about analyzing their sonograms with a good recording?

I looked at the very best on-line recordings from the Macaulay Library (collected via eBird, and there’s a collection of the best ones at Peterson Bird Sounds) and from xeno-canto. (Warning: the horizontal axis is different between their sonograms. Xeno-canto sonograms fit about two seconds in the space where Macaulay fits one second of recording, thus compressing the sonogram. Here, I stretched the xeno-canto sonograms horizontally to adjust for that.)

Willow whits

Dusky whits

Gray whits

It appears that Willow, with a good recording, is distinctive, with up to three harmonic tones and that downward slope after the upward slow. To the ear, the Willow whit is softer and sweeter than the others. Dusky and Gray, on the other hand, are both dry sharp whits, and virtually indistinguishable on the sonograms. Gray is more likely to go up to 10 kHz or higher, and that echo line on the first Gray sonogram was consistent on all the calls, at least for that individual recording. For the record, Least was similar to Dusky and Gray, although the triangular dark shadow to the right of the main call tended to be thicker and larger.

iPhone whit

iPhone recording

To the right is a typical iPhone recording, probably a Dusky. Based only on this sonogram, just a shadow of the good ones above, it could be any of the species. The take-home lesson is that one could probably diagnostically identify a Willow whit from a sonogram with a very good recording. The Dusky and Gray whits are too close to call.

Our discussion also focused on spring migration timing and incorporated Hammond’s (as many of these birds are silent). Again, I turned to eBird for some trends.

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whit map

Spring migration for western Empids. These maps are based on 2017-18 data. I excluded a few outliers in each case. Nevertheless, these dates represent the earliest arrivals. Most birds were a week later than the dates shown.

The results are that Hammond’s is the earliest, followed by Gray and then Dusky. For all three, however, there was a pulse of records during the last week of April. Willow is a full month behind the other two. In fact, even in southern Arizona there were very few Willow records before May 10.

Kaufmann empidsMuch has been written about Empid identification. Here’s a link to the Rowland 2009 article in Birding. My personal favorite is the chapter in Kenn Kaufmann’s Advanced Birding. The diagram at left is from the old version; the new one is even better, showing variations within species.

For the Hammond’s/Dusky challenge in spring, I put together the diagram below. These identifications were confirmed by calling birds, which are easily separated (Hammond’s says peep rather than whit).

HammondsDusky

Finally, if you’re still confused, there’s this infamous meme:

empid meme

Two of the nation’s top birding spots threatened by the wall

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Of the top 20 birding sites in the entire United States, based on the number of species reported on eBird, six of them are in south Texas. Two of them, Bentsen-Rio Grande Valley State Park and Santa Ana National Wildlife Refuge, are threatened by Trump’s proposed wall.

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RG border map

The map above, taken from an excellent article illustrating all of the natural resources at risk from California to Texas, includes the bird totals for the eBird hotspots associated with the at-risk parks and wildlife refuges. The wall is often constructed hundreds of yards north of the actual border (the Rio Grande River). It typically includes a swath of cleared land on each side of it.  At Bentsen and Santa Ana, the wall threatens to destroy critical remaining habitat and strand the parks in “no-man’s land”, preventing public access. Dozens of articles have been written regarding the impacts to everything from butterflies to ocelots.

Sabal Palm is unique, in that the natural area is south of the wall. Visitors pass thru the wall in order to visit the park. However, there is no guarantee this arrangement will be made at other sites. Should public access be denied at Bentsen, the park could revert back to the Bentsen family per a historical agreement. The national wildlife refuges are especially at risk. As they are already federal properties, the Administration doesn’t have to deal with acquiring private property. Thus, they are the easiest places to build.

 

 

The decline of Mountain Plovers in two graphs

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I live in Yolo County, California, near Sacramento, where Mountain Plovers used to be an annual winter specialty. Searching for “dirt clods with legs”, we used to be able to find dozens of these unique shorebirds, sometimes over a hundred.

Those days are over. They are now “irregular”, meaning we don’t find them every year. We’ve struck out five of the last eleven years. Before that, we averaged a high count of 72 individuals. The first graph, built from records in the Yolo Audubon Society newsletter, emails to the Central Valley Birds listserv, and eBird, shows the high count each winter in Yolo County.

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MOPL Yolo

This second graph backs out a bit in space and time, looking at all Mountain Plovers worldwide, starting in 1980. They are a bird of the steppe, breeding mostly on the Great Plains between the Rockies and the flat lands, between the Canadian and Mexican borders. They winter in open country in a vast arc west and south of there, mostly in California, Arizona, New Mexico, and Texas.

MOPL cbc

All the Christmas Bird Counts nationwide, plus Mexico, averaged 728 birds per count thru 1994, but have never hit that mark since. Fewer than 200 individuals have been enumerated six of the last ten years. Adjusted for party hours, the graph basically looks the same.