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At least 217 records · Page 12Linked to original sources
USGS1979

Winter feeding habits of quail in longleaf-slash pine habitat

Crops of bobwhite quail (Colinus virginianus) collected in 11 years (7,147 in winter and 92 in other seasons) in the longleaf-slash pine (Pinus palustris-P. elliottii) forest type were examined for food content. Seeds of woody plants made up 45% or more of the volume of food found in crops in 9 of the 11 winters. Seeds of pines (Pinus spp.), drupes of red bay (Persea borbonia), and acorns from various oaks (Quercus spp.) were large-volume food items in certain years. As a group, seeds produced by legumes were next largest in volume, varying from 2 to 48% in the 11 winters. Seeds of partridge peas (Cassia spp.), common lespedeza (Lespedeza striata), bush clovers (Lespedeza spp.), milkpeas (Galactia spp.), and tick-clovers (Desmodium spp.) were impor tant species. Volumes of seeds of grass, spurge, and sedge families were usually less than 12% for each group, and volumes of green leaves and animal matter less than 5% each. Panic (Panicum spp.) and paspalums (Paspalum spp.) were principal grass species. Availability of seeds influ enced consumption by forest-dwelling quail. In habitat management for quail, a variety of trees and shrubs should be maintained in the forest type to better insure a dependable food base, season to season and year to year. Similarly, desirable herbaceous food plants should be encour aged by fire and mechanical means.

Alabama, Arkansas, Florida, Georgia, Louisiana, Mi↗
USGS1980

The Rocky Mountain population of the western Canada goose: Its distribution, habitats, and management

The western Canada goose ( Branta canadensis moffitti ) was divided into a Rocky Mountain population (RMP) and a Pacific population (PP) on the basis of band recovery patterns examined in this study and recovery data from other investigators. Habitat information obtained from nine cooperating wildlife agencies within the RMP's range provided a base line for evaluating future changes in nesting, molting, and wintering areas. The habitat inventory indicated that none of the seasonal habitats were currently limiting the size of the RMP. The RMP's range is divided into 15 reference areas and these are briefly described. Past studies of Canada geese in the Intermountain Region are reviewed. Topics covered in the discussion of breeding biology are nesting chronology, spring population composition, breeding age, clutch size, nesting success. artificial nesting structures, and gosling survival. Much of the mortality of Canada geese occurs before the birds are fledged. Man-made nesting structures reduce losses during incubation. but research is needed on the relations between brooding sites and gosling survival. Some western Canada geese, mainly prebreeders and unsuccessful nesters, make molt migrations to and from molting areas during and after the brood-rearing season. More than half of these molt-migrants are yearlings too young to nest; there are indications that even some successful nesters leave nesting areas to molt before the fledging of their offspring. Geese 2 years old or older may serve as guides to traditional molting areas for the first-time migrants (i.e., yearlings). Lack of disturbance appears to influence selection of specific molting areas within the nesting range of moffitti , whereas movements of molters out of the Intermountain Region may be related to the evolution of this subspecies. Apparently. molters of both the PP and RMP that leave the Region go to the Northwest Territories of Canada. Although the taxonomic status of moffitti as related to the giant Canada goose ( B. c. maxima ) is unclear. these two subspecies are closely related. as evidenced by similar molt migrations to subarctic Canada. similar blood serum proteins. and only dinal differences in body size ,!!nd color. Mean annual survival rates for birds banded on nesting areas averaged 53 ± 2% ( X̿ ± SE) for immatures and 64 ± 1 % for adults. Mean annual survival rates of adults captured on molting areas averaged 70 ± 1 %. Sport hunting accounts for more than 86% of the mortality of fledged Rocky Mountain geese. and hunting may limit the population's growth. Because the number of waterfowl hunters in the Rocky Mountain West is increasing, the continued expansion or future maintenance of the RMP may require more restrictive hunting regulations. Other management recommendations include the refinement and standardization of spring and winter aerial surveys, and more accurate age and sex determinations when geese are banded and color-marked.

Alberta, Arizona, California, Colorado, Idaho, Mon↗
USGS1980

Breeding biology and relation of pollutants to black skimmers and gull-billed terns in South Carolina

The breeding biology and relation of pollutants to black skimmers ( Ryn chops niger ) and gull-billed terns ( Gelochelidon nilotica ) were investigated in South Carolina from 1969 through 1975. With few exceptions, the two species nested together in colonies located on barrier islands. We located 10 colonies, 7 of which were on the Cape Romain National Wildlife Refuge (Cape Romain); references were located that described nesting on seven other islands in South Carolina that no longer support colonies. Gull-billed terns nested from early May through July; the skimmers started later (late May) but also continued later (early September). Both species nested in areas subject to tidal flooding, and the two species persisted in nesting in several colonies despite intense predation by rats and gulls. Estimated reproductive success varied greatly from year to year and colony to colony; success in most colonies seemed low, particularly for the gull-billed tern. Residues of organochlorine pollutants in several eggs seemed of sufficient magnitude to induce adverse effects on reproductivity and eggshell thickness: however, the overall effect of organochlorines appeared negligible. Maximum numbers of nests located in a single year were 790 for the skimmer and 340 for the gull-billed tern: the total breeding population in South Carolina is unknown. Although nesting islands at Cape Romain and Deveaux Bank are sanctuaries for nesting birds, both species will continue to lose nesting habitat as additional sea islands are developed and inhabited by man.

South Carolina↗