Endemics of the United States Lower 48
Jun 28, 2020 | by Adrian Binns
An endemic species is one that is only found within specifically-defined boundaries, ecological areas, or habitats. Endemics can be identified in large or small areas – continents or countries, mountain ranges or islands. In the United States, the continental Lower 48 states encompass ~3 million square miles, and host 15 fully endemic bird species out of the ~560 regularly-occurring residents or breeders.
A review of US endemics reveals some interesting facts. Four (4) members of the corvid (crows and jays) family are endemic, of which 3 are also endemic to the state in which they reside. The sparrow and finch families each have 3 endemics, while the grouse family has 2. Blackbirds (Icteridae), woodpeckers, and chickadees have 1 each. More than half of the endemics (8 of them), can be found in Florida. Four (4) endemics are found in Colorado. For birders who like to keep lists – or anyone who enjoys unique species – tracking down endemics is an exciting experience! Many of our birding tours throughout the United States focus on these rare, range-restricted species!
Yellow-billed Magpie Pica nuttalli – found in open oak woodlands in California’s Central Valley and south to Santa Barbara County. Its range does not overlap with the more widespread, common, and larger Black-billed Magpie. It is one of 3 US endemics that is solely endemic to one state. Yellow-billed Magpies can be seen on our California: Central Coast trip each September. On some occasions we have even found mega-flocks containing 60 to 80 of these colorful magpies!
Island Scrub-Jay Aphelocoma insularis – the most range-restricted of all the US endemics, this species is totally confined to the 96 square-mile Santa Cruz Island offshore from Santa Barbara, California. This large island is part of California’s Channel Islands which are well-known for containing endemic flora and fauna. Though these large jays are common at this location, the population is estimated at ~2500, making it one of our country’s rarer songbirds. Island Scrub-Jay and other Santa Cruz Island specialties can be seen on our 5-day California: Condor, Island Scrub-Jay & LA Exotics trip which precedes our 8-day January California: South Coast, Deserts, & Mountains tour.
Lesser Prairie-Chicken Tympanuchus pallidicinctus – very similar in appearance to Greater Prairie-Chicken, but as the name suggests the Lesser Prairie-Chickens are smaller. This species has a very restricted range in the southern Great Plains. Populations of both prairie-chicken species overlap in a very small area of Kansas where hybridization is known to occur. Lesser Prairie-Chickens are found in sandy sagebrush flats and shinnery oak prairies. Their numbers have declined dramatically in the last century as a result of hunting, habitat loss, wildfires, and livestock overgrazing. Lesser Prairie-Chicken can be seen on our Colorado: Chicken Odyssey trip.
Gunnison Sage-Grouse Centrocercus minimus – was recognized in 2001 as separate from the larger and more widespread Greater Sage-Grouse when differences in calls, plumage, and lekking displays were documented to support a split. At the time it was the first new bird species described in the US since the 19th century! Populations are restricted to just two small areas in south-central Colorado and southeastern Utah where these shy grouse hide away in vast sagebrush country. Numbers of this endangered species have dropped dramatically to fewer than 4000 birds total. Gunnison Sage-Grouse can be seen on our Colorado: Chicken Odyssey trip.
Black Rosy-Finch Leucosticte atrata – breeds in the rocky tundra above the treeline of the central Rocky Mountains and northern Great Basin’s mountains. In winter it forms large flocks often mixed with the other two species of rosy-finch, and often moves to lower elevation at the edge of snowfields to forage, but can also be seen visiting feeders. Black Rosy-Finch can be seen on our Colorado: Chicken Odyssey; Utah & Nevada: Himalayan Snowcock, Cassia Crossbill & Flammulated Owl target tour, and on our New Mexico: Rosy-finches, Snow Geese & Sandhill Crane Spectacle target tour.
Brown-capped Rosy-Finch Leucosticte australis – the most range-restricted of the three rosy-finches, this species is only found at high elevations in the Rocky Mountains, primarily in Colorado and also northern New Mexico. This species is very similar to the Gray-crowned Rosy-Finch but has a darker crown and often more extensive rosy color than the interior form of Gray-crowned. Brown-capped Rosy-Finch can be seen on our Colorado: Chicken Odyssey and also on our New Mexico: Rosy-finches, Snow Geese & Sandhill Crane Spectacle short trip.
Cassia Crossbill Loxia sinesciuris – the newest member to the US endemics list, after being split from the Red Crossbill complex in 2017. The Cassia Crossbill is named for the county in which it occurs, giving you an idea of how small its range is! It is a year-round resident of Lodgepole Pine forests in the South Hills and Albion Mountains of south-central Idaho. These isolated mountains are absent of Red Squirrels, and this species of crossbill has evolved to fill the ecological niche that would normally be handled by the squirrels! Cassia Crossbills are identical to Red Crossbills, and overlap with the widespread and nomadic Type 2 Red Crossbill, so Cassia is best identified by calls. Cassia Crossbill can be seen on our Utah & Nevada: Himalayan Snowcock, Cassia Crossbill & Flammulated Owl short trip.
Boat-tailed Grackle Quiscalus major – these large, gregarious blackbirds can be found along much of the Atlantic and Gulf Coast shoreline, but they are confided largely to saltmarshes habitats from Long Island, NY to southern Texas. In Florida this species has also adapted to urban habitats. Boat-tails are slowly expanding their range northward. Boat-tailed Grackle can be seen on many of our tours including the New Jersey: Harlequin Duck, Long-tailed Duck & Purple Sandpiper short tour, Cape May to Hawk Mountain, Florida: Central Specialties, South Florida & Dry Tortugas, Texas: Rio Grande Valley in Spring and Texas: Rio Grande Valley in Fall trips.
Fish Crow Corvus ossifragus – similar to American Crow, but slightly smaller and with distinctive, nasal calls. Fish Crows are found along the East Coast from Massachusetts to Florida, and west into Texas. As the name suggests, these crows are often associated with more riparian habitats, and the species is slowly expanding its range northward along river corridors in the Midwest and Northeast. Fish Crow can be seen on a number of our tours including Massachusetts: Thick-billed Murre, Dovekie & Snowy Owl, New Jersey: Harlequin Duck, Long-tailed Duck & Purple Sandpiper, Cape May to Hawk Mountain, Florida: Central Specialties, and South Florida & Dry Tortugas trips.
Carolina Chickadee Poecile carolinensis – the southern counterpart to the Black-capped Chickadee, with whom it hybridizes where their respective ranges overlap. In recent decades the Carolina Chickadee’s range has been moving northward, and the hybrid zone increasing. This species is smaller and plainer in color than the Black-capped. Carolina Chickadee can be seen on our New Jersey: Harlequin Duck, Long-tailed Duck & Purple Sandpiper, Cape May to Hawk Mountain, Ohio & West Virginia: Follow the Birds to “The Biggest Week”, Florida: Central Specialties, and the Texas: Black-capped Vireo & Golden-cheeked Warbler short trip.
Saltmarsh Sparrow Ammospiza caudacuta – totally restricted to salt and brackish marshes from southern Maine to North Carolina during the breeding season, and then Delaware to central Florida over the winter months. It was formerly known as Sharp-tailed Sparrow reflecting the pointed tips to their tail feathers. Sharp-tailed Sparrow was split in 1995 to form Saltmarsh Sparrow and Nelson’s Sparrows, respectively. Saltmarsh Sparrow is the rarest of the 3 salty-sparrows, and is fighting a losing battle against sea-level rise and habitat loss. Their population number drops an astonishing 9% per year! You read that correctly! Saltmarsh Sparrow can be seen on our Maine: Mountains & Coast trip and the Cape May to Hawk Mountain trip.
Seaside Sparrow Ammospiza maritima – a common inhabitant of tidal saltmarshes along the Atlantic and Gulf Coasts and the largest of the 3 salty-sparrows. These are readily told apart from Nelson’s and Saltmarsh by their overall gray plumage and larger size. Of note, the ‘Cape Sable’ subspecies is endangered, and found only in the Everglades. The ‘Dusky’ subspecies has officially gone extinct. Seaside Sparrow can be seen on 5 of our tours including Massachusetts: Thick-billed Murre, Dovekie & Snowy Owl, New Jersey: Harlequin Duck, Long-tailed Duck & Purple Sandpiper, Cape May to Hawk Mountain, Florida: Central Specialties, and our South Florida & Dry Tortugas tours.
Bachman’s Sparrow Peucaea aestivalis – this near-threatened and secretive sparrow is found in open pinewoods of the southeastern states where it sings conspicuously in springtime from open pine perches and Saw Palmetto. Following range expansion northward in the early 20th century, their range is now shrinking as a result of logging. Bachman’s Sparrow can be seen on our Florida: Central Specialties and South Florida & Dry Tortugas trips.
Red-cockaded Woodpecker Dryobates borealis – another southeastern pine specialist with strict habitat requirements. These woodpeckers need large tracts of old growth forest, especially Longleaf Pine, that receive intense and regular burns to keep the understory mostly clear and open. Often found alongside Bachman’s Sparrows, this endangered woodpecker is a cooperative breeder, living in small family groups known as clans, and nesting in cavities. Red-cockaded Woodpecker can be seen on our Florida: Central Specialties and South Florida & Dry Tortugas trips.
Florida Scrub-Jay Aphelocoma coerulescens – the only species that is fully endemic to Florida. Isolated populations are found in large tracts of short scrub-oak habitat on sandy ridges and dunes in the center of the state. It is a cooperative breeder with offspring from the previous year’s brood helping raise the young. Habitat fragmentation and reduction of their specialized habitat is contributing to a steady population decline of 90% over the last century. Even though their numbers are declining, they are still friendly birds often willing to approach closely or even land on your head! Florida Scrub-Jay can be seen on our Florida: Central Specialties and South Florida & Dry Tortugas trips.
If Alaska was included in this profile, McKay’s Bunting would be the 16th endemic species. As one of the rarest breeding birds in North America, McKay’s Bunting is found only on a couple of islands in the Bering Sea off the Alaskan coast. In winter it ranges from Alaska south to British Columbia, and sometimes strays to Washington or Oregon.
While there are 15 endemic species in the United States’ Lower 48, there are a handful more that just miss this special list and have ranges just slightly overlapping with neighboring countries. To the north; Henslow’s Sparrow is found in Ontario, White-headed Woodpecker in British Columbia, and Greater Sage-Grouse in Alberta and Saskatchewan, Canada. Harris’s Sparrow is the only breeding endemic to Canada, but winters in the south-central United States.
To the south; Juniper Titmouse and Abert’s Towhee inhabit parts of northern Sonora, Mexico while California Scrub-Jay, Pinyon Jay, Mountain Quail, California Condor, Nuttall’s Woodpecker, Wrentit, California Thrasher, and Tricolored Blackbird are almost entirely restricted to the Lower 48 by do range several hundred miles into Baja California, Mexico.
Brown-headed Nuthatch, a pine-forest resident of the southeast, has a small endangered population in the Grand Bahamas, otherwise it would be on the Lower 48 endemic list. Similarly, the threatened Kirtland’s Warbler nests almost exclusively within Wisconsin and Michigan, but overwinters in the Bahamas.
This long listing of near-endemic species are still best seen in the United States, where the bulk of their populations reside, and all can be seen on various tours that we offer. Each of the above profiled endemic species can be seen on one or more Wildside Nature Tours trips each year. To discover and experience these unique birds, please check out our schedule and plan for your next target today!