“Listen. Those birds don’t sound like crows,” my husband Bruce said, “but they look like crows.”
He pointed to blackbirds perched on the light poles and flying above Wegman’s parking lot in State College.
They sounded as if they were American crows with colds in their noses, a nasal “eh-uh.” But they looked like American crows.
Later, I learned they were fish crows and that they had slightly smaller bodies, more tapered wings, faster wingbeats, and shorter legs than American crows. Such differences are almost impossible to note in the field, which is why most birders can only positively identify fish crows by their unique calls. These crows live along the Atlantic and Gulf coasts from Maine to east Texas and inland along major rivers from Pennsylvania south to Mississippi.
Fish crows were first observed along the Delaware and Schuylkill rivers in Philadelphia by Scottish ornithologist/artist Alexander Wilson, who named them Corvus ossifragus in 1812. And ornithologist/artist John James Audubon mentioned seeing them in the 1830s along the Delaware River almost to its source. By 1903 they were nesting in small Philadelphia parks including a park across from the Academy of Natural Sciences, where the fish crows stole skeletons that taxidermists had put out to bleach on the roof.
Since then, they have moved up all our major and minor river valleys north and west including, in the last couple decades, the Ohio River drainage.
Like American crows, fish crows are opportunistic. Not only have they expanded their habitat from coastal marshes and beaches to lakes and rivers but also to farmlands, wooded neighborhoods, and suburban areas.
Their food choices are omnivorous—carrion, trash, berries and other fruits, grain, crabs, turtle eggs, and nestlings and eggs of songbirds such as blue jays, red-winged blackbirds, brown thrashers, common grackles, and northern mockingbirds and water birds including herons, gulls, ducks, plovers, rails, terns, and double-crested cormorants. They even will nest in heron colonies and raid their nests, and when they find a good source of food, they may cache it to eat later or to feed to their nestlings.
If they migrate at all, it is only to good sources of food such as landfills, feed lots, and malls and shopping centers with accessible dumpsters. They usually join winter roosts of American crows but return to their breeding grounds as early as February in Pennsylvania.
Fish crows are monogamous and have no courtship displays, although Kevin McGowan, who studied them in Florida, wrote in his Birds of the World account that he observed “a nest-building crow with stick in its bill flying slowly with stiff wings in exaggerated ‘butterfly fashion’ circling nest site completely before going to nest, repeated several times,” but whether or not that was a courtship display has not been determined. However, mated pairs do preen the back of each other’s heads.
Both sexes build their nest in tall trees as high as 80 feet. It takes them approximately nine days, although they start several nests before lining and finishing one. They may use the same tree sometimes for years, but they always build a new nest of deciduous tree sticks and line it with soil, red cedar, or grapevine bark, hair and/or pine needles. The finished product is 19 inches across with a cup of five inches.
Here in Pennsylvania fish crows may build a nest as early as April 11 or as late as June 29. They have a small territory around their nest tree, and occasionally they will breed semi-colonially among several other fish crow pairs with nests within 100 yards of each other. The male fish crow defends the nest site from American crows, but he will often allow other fish crows to approach his nest.
The female fish crow lays two to six pale bluish-green eggs marked with brown which she incubates while the male guards and feeds her, bringing food in his throat not his bill, both for his mate and later his nestlings.
Both mob possible nest predators, most notably hawks, raccoons, owls, and humans. After the eggs are incubated for 16 to 19 days, the naked, helpless young emerge and take 32 to 40 days to mature and fledge.
Fish crows have not been studied as much as American crows but like their congeners they are curious, intelligent and social birds that will play with objects they find. However, they can be aggressive toward each other, for instance, a fish crow at a garbage site was observed pulling the tail of another fish crow which then flew away.
More serious fights begin with threatening posturing, during which they arch their necks, hold their heads forward and point their bills downward, spread their tails, slightly spread their wings or keep them close to their bodies with their wing tips down, and walk sideways toward their opponent. After fights, they perform an appeasement display consisting of open-mouthed begging calls, lowering their bodies and quivering their extended wings, and they always give in to American crows in fights.
Although I can easily see and hear fish crows in State College and on the Penn State campus where they roost in the winter and breed locally, I have yet to see and hear them in my own Blair County. But other folks have because the fish crows have come by way of the Frankstown Branch of the Juniata River into our county. The first record was April 15, 2006 by Roy Boyle at the north end of Altoona.
Closer to our home on Brush Mountain in northern Blair County, our son Mark heard a fish crow in Sinking Valley below our mountain in April 2015 and frequently saw them in the springs of 2016 and 2017 over the farmland between Tyrone and Bellwood and on the wetland behind the Northern Blair County Recreation Center.
The following July (2018) Mark and our other birder son Steve were sitting on our veranda when they heard a fish crow call as it flew above Sapsucker Ridge. Then from March 19 until July 14, 2020 Mark saw fish crows along the Little Juniata River at the base of our mountain. His highest number was 12 on March 19. And the most he saw fly over our farm together were six fish crows on March 31. But most days he had one or two throughout the spring, summer, and as late as October 9. Clearly they were attracted by the river.
While in Pennsylvania the highest number of fish crows are in the lower Susquehanna River valley in the counties of York, Cumberland, and Lancaster and along the lower Delaware River and its tributaries, they have greatly expanded their range from the first to the second atlasing of Pennsylvania breeding birds according to Douglas A. Gross. They are “strongly associated with pasture in Pennsylvania,” he wrote in the Second Atlas of Breeding Birds in Pennsylvania. Since they are scarcely ever above 1000 feet and rarely ever in densely forest areas, I can’t expect to see them breeding in our tall trees at 1200 feet in elevation, but they have increased 86% in the number of blocks of fish crow records from the first Atlas of Breeding Birds in Pennsylvania. Their state population is estimated to be about 30,000 and nationwide 450,000 according to Partners in Flight. Even though West Nile virus killed many in the early 2000s, their numbers have recovered. But as Gross concludes, “Although it [fish crow] has made advances, it is not nearly as common and widespread as the seemingly ubiquitous American crow.”