Monday, October 10, 2011

Red-crowned Parrot

There's a lot of interest in Red-crowned Parrot since the US Fish and Wildlife Service responded favorably to a proposal to list the species (see the federal register notice here). I am posting this account - long held in draft form - to pique your interest in the species and its distribution in south Texas. You can also read about a local grass-roots effort by the Rio Grande Valley Birding Festival to help the Red-crowned Parrots in Harlingen on their blog.

Red-crowned Parrot
Amazona viridigenalis
IUCN Status: Endangered

The Red-crowned Parrot is a familiar resident of the Lower Rio Grande Valley’s urban habitats. This species forms large flocks in winter in the area of Brownsville, Harlingen, and McAllen. The flocks roam the area, flying out in the morning in search of food, and returning to roost in the evening. Flocks often roost in traditional locations, though these may change through the course of the winter.

Pairs are evident in the winter as mates allopreen (preen each other). Pairs seem to remain together through the winter. In spring, flocks break into smaller and smaller groups as pairs search for suitable cavities to enlarge. Nest cavities are often in dead palm tree trunks, either in the top of the snag or in enlarged holes in the trunk. Red-crowned Parrots in the LRGV have been seen nesting with other species of Amazon parrots (including Yellow-crowned Parrot for several years at Allen Williams in Pharr) and hybrid offspring have been produced. Younger non-breeding birds form small flocks in summer. Like most Amazon parrots, Red-crowned Parrots do not nest until they are several years old.
Confusion species are all believed to be exotic in origin, with the most frequently reported species Yellow-headed Parrot, Red-lored Parrot, Lilac-crowned Parrot, and Yellow-crowned Parrot. Hybrids of these species with Red-crowned may occur. Compare female Red-crowned with smaller Lilac-crowned Parrot.

The voice of the Red-crowned Parrot is a distinctive raucous series of calls usually given in flight. As with most parrots, they have many voices, but the harsh grating tones and raucous voice is unmistakable where other large Amazons are unlikely. Listen here to one of John Arvin's recordings on the WBC site.

Females have less extensive red on the crown compared to males, though this is often easiest to see in pairs. Younger birds have gray irises, changing to light brown to yellow in adults. Field work in Mexico showed individuals with yellow feathers in the head and body, and others with the bend of the wing red (Enkerlin and Hogan 1997).

The Red-crowned Parrot was not present in the valley historically. The earliest records are in the mid-80’s, and by the late 80’s they were present across the valley. There is no agreement as to the origin of these birds, with some advocating that the birds came from Mexico in response to a severe drought, and having found the well irrigated urban environments of the LRGV they decided to stay. Others believe that the flocks had their origin from captive birds. Regardless of the source of the flocks in Texas and those known to be of captive origin in Puerto Rico, Florida, California, and Hawaii, there are now more Red-crowned Parrots in the United States than in their native range.
This chart shows the number of Red-crowned Parrots per party hour as recorded on Texas Christmas Bird Counts from count year 82 (1980-1981) to count year 110 (2009-2010). The wild fluctuations may be the small number of counts driving the numbers, the variable number of observers on each count each year, and the difficult some years finding the flocks other than at dawn and dusk, but only if you know where they are roosting.

Counts with Red-crowned Parrots present include:
* Anzalduas/Bentsen - 1 year - count 94 (1993-1994)- 2 birds. The McAllen flock rarely wanders west to Mission.
* Brownsville - 4 years - count 110 (2009-2010) - 143 birds.
* Harlingen - 13 years - count 107 (2006-2007)- 163 birds.
* Santa Ana - 17 years- count 102 (2001-2002)- 200 birds.
* Weslaco - 7 years - count 107 (2006-2007) - 159 birds. Weslaco has recorded Red-crowned Parrot every year this relatively new count has been conducted.

Range maps for Red-crowned Parrots are generally based on Howell and Webb (1990). The map at NatureServe includes the introuced populations in Puerto Rico as Exotic but does not map the US populations well. A much better map of the Mexican range of the Red-crowned Parrot is in the IUCN Red List of Threatened Species here.

The Red-crowned Parrot has several conservation issues that can be addressed, including limited nest sites, lack of protection and harvest for the pet trade, hybridization, and destruction of riparian corridor and foothill habitats in the native range in Mexico. The Rio Grande Valley Birding Festival is providing parrot and parakeet nesting towers to provide additional sites for these birds to nest. Leaving dead palm tree trunks standing or "planting" these dead trunks in safe areas provides much needed nesting structure. Red-crowned Parrot is not protected under the Migratory Bird Treaty Act. The MBTA provides the majority of the protection for birds in the United States, and at the time the Treaty was was written there were no wild parrots left in the United States as the Carolina Parakeet was extinct. Parrots could be added to the treaty to ensure protection for the Red-crowned Parrot. The city of Brownsville has legislation that protects the Red-crowned Parrot, and other cities are contemplating taking action to protect these birds and their nests. Protection of nest sites, and the riparian corridor and foothill forests used by these birds in Mexico, is desperately needed to maintain the native population in Tamaulipas and Nuevo Leon.
Where to see this species:
Absent or very rare at many World Birding Center sites. See Valley Nature Center's brochure or webpage for suggestions, or the Rare Bird Alert ( Try Downtown Brownsville, Harlingen, Weslaco, and McAllen. Also consider - University of Texas - Brownville Campus; Olivera Park, Brownville; Pendleton Park, Harlingen; Valley Nature Center, Weslaco; Frontera Audubon Center, Weslaco; Quinta Mazatlan World Birding Center, McAllen; Allen Williams' Backyard, Pharr.

Online References:

Enkerlin-Hoeflich, E. C., and K. M. Hogan. Red-crowned Parrot. Birds of North America. This series is extremely useful but it is a fee site. The fees are discounted to Texas Ornithological Society members and free to American Ornithologists Union members. Join!
IUCN Red List 2011
NatureServe InfoNatura 2011