Tamaulipas Crow

Tamaulipas Crow (Photo by the Rio Grande Delta Audubon)
Tamaulipas Crow (Photo by the Rio Grande Delta Audubon)

Since it is Cinco de Mayo today…I decided I would share with you the Tamaulipas Crow (Corvus imparatus) from a small part of Mexico in the Northeast.
It is on the Audubon WatchList and here is some great information on it from the Audubon Watchlist:1

Tamaulipas Crow
(Corvus imparatus)

This species was on the 2002 WatchList, but is not on the 2007 WatchList. Please refer here for information on the 2007 WatchList.

This is a small crow whose range is limited to the Tamaulipas region of northeastern Mexico, extending just into the lower Rio Grande Valley of extreme southeastern Texas. It is the counterpart of the Sinaloa Crow of the Pacific slope; in fact, the two are considered conspecific by some.

The Tamaulipas Crow is a small crow, very shiny in appearance, black overall but with a purplish tint above and purplish to bluish-green gloss underneath. The bill is small and short. Its call is much like that of the Fish Crow, but Fish Crows are not found in this region.

Distribution and Population Trends
This species’ range extends primarily through the Tamaulipas region of Mexico, reaching into extreme southern Texas, into the lower Rio Grande Valley. It is common within its range, but its range is very limited. The species was first reported in Texas in 1968, and although they are often found along the lower Rio Grande, they are likely only feeding there, breeding only in Mexico.

It is found in open and semi-open woodlands and lowland scrubby farmland, sometimes in semi-desert habitats. It may be found in villages and ranches. In southeastern Texas, it is found primarily around the garbage dump at Brownsville. Believed to nest in loose colonies. The nest is a platform or shallow basket made from sticks and plant materials, with soft material lining the inside. It is usually in a tree. Typically, four eggs are laid in early April. The Tamaulipas Crow scavenges for refuse and eats carrion, insects, and seeds, and, like other crows, it likely also eats other birds’ eggs, berries, and nuts.

Although the population is stable, conversion of scrubland to farmland poses a threat to this species, especially considering its very limited range.

In the U.S. portion of this species’ range there has been extensive work to begun restoring and protecting the remnant forests of the lower Rio Grande Valley of south Texas. The Lower Rio Grande Valley National Wildlife Refuge has been working since 1979 to protect habitat and restore native vegetation. The refuge encompassed more than 90,000 acres in more than 100 separate parcels as of 2002 and is expected to eventually include over 130,000 acres. Texas Parks and Wildlife is developing its World Birding Center in south Texas for launch in 2003 with the goal of engaging both local communities and visitors in state-of-the-art education, restoration and conservation projects, while offering new habitat areas to birdwatchers.

What Can You Do?
Information on where Tamaulipas Crows occur and in what numbers is vital to conserving the species. Help in monitoring this and other species by reporting your sightings to eBird. A project of Audubon and the Cornell Lab of Ornithology, eBird is the world’s first comprehensive online bird monitoring program: click here.

Volunteers are crucial to the success of programs that monitor the status of populations of Tamaulipas Crows and other bird species. Audubon’s Christmas Bird Count (CBC) is one of the longest-running citizen-science monitoring programs in the world and has helped to follow changes in the numbers and distribution of Tamaulipas Crows. To learn more about the CBC and how you can participate, visit here.

CIPAMEX, Audubon’s BirdLife International partner in Mexico, has an Important Bird Areas program that is working to protect habitat for Tamaulipas Crow and many other species. To learn more about Mexico’s Important Bird Areas program and how you can help visit them here.

Kaufman, Kenn. 1996. Lives of North American Birds. Houghton Mifflin Company, Boston, MA.

Madge, Steve and Hilary Burn. 1994. Crows and Jays. Princeton University Press, Princeton, NJ.

  1. http://audubon2.org/watchlist/viewSpecies.jsp?id=202 []