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Quail Declines

CITIZEN SCIENCE AND BIRD CONSERVATION

Citizen science efforts such as the Great Backyard Bird Count can tell us a lot about the health of our environment. For example, data from two similar projects, the Christmas Bird Count (CBC) and the Breeding Bird Survey (BBS), are vital in allowing us to monitor the status of quail and other bird populations in North America. Your input for the GBBC can also help us in this effort.

NORTH AMERICAN QUAIL SPECIES

Six species of quail are native to North America north of Mexico (see below). One or more species of quail are found in at least 44 U.S. states, though introductions and repeated releases of birds have undoubtedly increased and maintained a somewhat expanded range for some species, particularly the Northern Bobwhite. Only one quail species, the Northern Bobwhite, occurs east of the Mississippi River. The greatest diversity of quail occurs in the southwestern U.S. with Arizona, Nevada, New Mexico, and Texas each hosting four species and California with three species. Have a look at our GBBC Maproom to see which of these species were reported in your area in previous years.

The quail plates on this page were painted by David Sibley, and are from his latest book The Sibley Guide to Birds. The maps showing population trends for each species were created by John Sauer and others at the Patuxent Wildlife Research Center using data from the Breeding Bird Survey. We thank them for allowing us to use these images on our site.

Two of our six quail species, Northern Bobwhite and Scaled Quail, are showing significant population declines across their range. Of the other four species, two (California and Gambel's Quail) seem to be doing well at this time, and the other two (Montezuma and Mountain Quail) are difficult to assess using the available data. For more information on each species see below

 

Northern Bobwhite, Colinus virginianus BobwhiteSibley

Habitat: Brushy pastures, grassy roadsides, farmlands, and open woodlands.

Population Trend: Northern Bobwhite have been declining by almost 3% annually throughout their range since 1966, as shown by the red areas in the Breeding Bird Survey map below. Data from the Breeding Bird Survey (BBS) and Christmas Bird Count (CBC) show a very similar declining trend (below). BobwhiteMaps



Scaled Quail, Callipepla squamata

ScaledQuailSibley

Habitat: Dry grasslands and brushy deserts.

Population Trend: Scaled Quail are declining by 2.4% annually throughout their range, as shown by the red areas in the Breeding Bird Survey map below. Data from the BBS and CBC are closely matched for this species as well (below).

ScaledQailMap



California Quail, Callipepla californicaCaliforniaQuailSibley







Habitat: Brushy chaparral foothills and live-oak canyons; adjacent deserts and suburbs.

Population Trend: CBC data from the 1980s showed a significant decline of 1.6 % annually. Subsequent BBS data show a recovery in the 1990s.

CaliforniaQuailMaps



 







 MountainQuailSibley

Mountain Quail, Oreortyx pictus





Habitat: Dry mountains, brushy wooded areas, and chaparral.

Population Trend: CBC and BBS data may not accurately reflect the status of this species. This species is believed to be declining in parts of its range (see below). The trends shown on the map below are not statistically significant and may be slightly misleading.
MountainQuailgraph




Gambel's Quail, Callipepla gambelii GambelsQuailSibley






Habitat: Desert thickets and arid country.

Population Trend: Although Gambel's Quail are decreasing in certain areas, overall their numbers seem to be increasing or staying level.
GambelsQuailMap



Montezuma Quail, Cyrtonyx montezumae MontezumaQuailSibley




Habitat: Grassy and brush-covered ground in pine-oak woodlands.

Population Trend: The status of Montezuma Quail cannot be accurately assessed using BBS or CBC data.


WHAT ARE THE MAJOR CONSERVATION ISSUES FOR QUAIL?

Land-use at the broadest scale is the most important factor impacting quail populations. In particular, grazing practices that reduce the amount of cover are probably the single most important factor causing declines in many quail populations including Scaled Quail and Montezuma Quail. In other areas, suppression of regular fire regimes, conversion to agriculture, and development are important factors.

FLAGSHIP REPRESENTATIVES OF NATURAL SHRUB/SCRUB-SAVANNAH HABITATS

Although quail are, in general, birds of open or shrub/scrub habitats, each quail species is characteristic of a specific habitat type or ecoregion of North America. For example, Mountain Quail occur above 700 meters on brushy slopes in the mountains of far western North America. Scaled Quail are characteristic of the shrublands of the Chihuahan Desert and Pecos and Staked Plains ecoregions of the southwestern United States. Gambel's Quail are most closely associated with the Sonoran Desert ecoregion. Many other species of birds share these habitats with quail species and many are declining (Elf Owl, Curve-billed Thrasher, Black-chinned Sparrow, Sage Sparrow, Cassin's Sparrow, etc.). Grassland and shrub/scrub bird communities have the most declining bird species of any group in North America. Quail are one of the most visible and easily identified bird groups. Because they are also a highly prized game bird, there is a strong constituency of both game and nongame interests that could be united to work towards the conservation and proper management of the shrub/scrub and grassland savannah habitats that all these species depend on.

David Sibley

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