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Amino acid composition of the meats of wild and farm pheasants were compared. The following amino acids were determined: Asp, Thr, Ser, Glu, Pro, Gly, Ala, Val, Ile, Leu, Tyr, Phe, His, Lys, Arg. An improved amino acid profile was found in the breast muscle of pheasants kept at the farm in comparison with that of wild pheasants.

Those charged with regulating waterfowl harvests must cope with random environmental variations, incomplete control over harvest rates, and uncertainty about biological mechanisms operative in the population. Stochastic dynamic programming can be used effectively to account for these uncertainties if the probabilities associated with uncertain outcomes can be estimated. To use this approach managers must have clearly-stated objectives, a set of regulatory options, and a mathematical description of the managed system. We used dynamic programming to derive optimal harvest strategies for mallards (Anas platyrhynchos) in which we balanced the competing objectives of maximizing long-term cumulative harvest and achieving a specified population goal. Model-specific harvest strategies, which account for random variation in wetland conditions on the breeding grounds and for uncertainty about the relation between hunting regulations and harvest rates, are provided and compared. We also account for uncertainty in population dynamics with model probabilities, which express the relative confidence that alternative models adequately describe population responses to harvest and environmental conditions. Finally, we demonstrate how the harvest strategy thus derived can \"evolve\" as model probabilities are updated periodically using comparisons of model predictions and estimates of population size.

We studied the spatial covariation of breeding success of black grouse and capercaillie and densities of mammalian generalist predators in Finland. Our study was based on six years' data from the Finnish wildlife triangle censuses (1989-1994). At the nation-wide level (100 × 100 km grids), the proportion of hens with a brood in August covaried regionally in the two species and decreased towards southern Finland, whereas the brood sizes were not related to latitude. The relative densities of red fox and pine marten correlated negatively with the proportion of grouse hens with a brood and were two- to three-fold higher in southernmost Finland than elsewhere in the country. The relative density of stoat, however, increased with latitude. The results support the hypothesis that higher generalist predator densities are responsible for lower breeding success of forest dwelling grouse moving southwards in Fennoscandia. The results also suggest that the stoat is of minor importance as nest and brood predator compared to red fox and pine marten. In northern Finland, on a smaller spatial scale (about 25 km2), the increasing red fox density decreased the probability of an observed grouse hen being with a brood in low vole years, whereas in years of high vole densities no effect was detected in logistic regression analysis. In contrast to northern results, the red fox density in southern Finland, although generally higher, did not predict the spatial variation in breeding success of grouse either in high or in low vole years. The brood size of grouse was not related to red fox density. Our results agree with the alternative prey hypothesis in northern, but not in southern Finland. In addition to higher amplitude of vole cycles in northern than in southern Finland, this inconsistency can probably be related to regional differences in both prey and predator communities.

In Great Britain, the captive rearing and release of ring-necked pheasants (Phasianus colchicus) during summer to supplement wild stocks for shooting is widespread, but breeding success of surviving females the following spring is poor. We hypothesized that reduced body condition as caused by low availability of natural food during spring and cessation of supplemental feeding in late winter may affect subsequent breeding success. On an estate in southern England, we provided wheat grain on 3 1-km2plots from March to June, while pheasants on 3 other 1-km2plots foraged solely on natural foods. We switched treatments during the second year. We collected hen pheasants from each plot during February and April. Fat reserves of hen pheasants collected in April from food-supplemented plots were maintained at their February levels (76.9 ± 8.0 g; x̄ ± SE), but fat reserves of birds collected from unsupplemented plots were reduced by >50% of their February levels (34.7 ± 6.9 g; P = 0.01). Body mass, muscle sizes, ceca, and small intestine length were more affected by date than supplemental feeding. We suggest that low food availability and poor spring diet as a result of modern agriculture may affect hen body condition and productivity of pheasants in Great Britain.

Estimates of duckling survival are necessary to accurately assess recruitment of mallards (Anas platyrhynchos), yet few reliable estimates exist. During 1988-90, we estimated survival rates for 127 radio-marked mallard ducklings from 64 broods on Lower Klamath National Wildlife Refuge, California. In 1988, we restricted the survival estimate to the first 10 days post-hatch (Ŝ = 0.18, SE = 0.07). Survival from hatching to 50 days was 0.37 (SE = 0.09) in 1989 and 0.34 (SE = 0.07) in 1990. Total brood loss differed among years (P < 0.05); 81.2% in 1988 (n = 16), 36.8% in 1989 (n = 19), and 37.5% in 1990 (n = 24). Ninety-three percent of mortality occurred during the first 10 days of life. We detected no differences in the proportion of radio-marked ducklings fledged from early-hatched versus late-hatched nests (P = 0.74). During 1989-90, 16 females appeared to lose their entire brood; however, 3 radio-marked ducklings from 2 of these broods were fledged by other brood hens. Of 29 radio-marked ducklings that reached 44 days of life, 6 (20.7%) joined other broods. Habitat enhancement is the key to improving duckling survival because the large number of predator species that consume ducklings makes predator control difficult.

Nothing is more evocative of the Texas outdoors than the whistled call of the bobwhite. While the familiar two-note greeting is now just a memory for most of us who live in the state’s growing urban sprawl, this bird is an economic commodity on par with crops and livestock in some regions of Texas. Three other native species of quail also inhabit Texas. Like the northern bobwhite, the scaled quail is significant as a game bird. The other two species, Gambel’s quail and Montezuma quail, are found in limited areas of southwestern Texas and represent an important indicator of forest, rangeland, and habitat conditions. Texas Quails presents the first complete assessment of the four species of quail found in this vast state. Experts describe each of them and examine all geographic regions of the state for historical and current population trends, habitat status, and research needs. These experts also discuss management practices, hunting issues, economics, and diseases. With the recent creation of the Texas Quail Conservation Initiative, this volume provides a timely and comprehensive view of quail science and stewardship.

We evaluated the influence of insect reductions on survival of sage grouse (Centrocercus urophasianus) chicks with 148 captive individuals aged 2-45 days when treatment began. Captive sage grouse chicks <21 days old needed insects for survival and development, whereas birds >21 days old required insects for optimum development. Quantity of insects in the diet was correlated with sage grouse chick survival and growth.

Determining factors that limit winter survival of waterfowl is necessary to develop effective management plans. We radiomarked immature and adult female mallards (Anas platyrhynchos) after the 1988 and 1989 hunting seasons in eastcentral Arkansas to test whether natural mortality sources and habitat conditions during late winter limit seasonal survival. We used data from 92 females to calculate survival estimates. We observed no mortalities during 2,510 exposure days, despite differences in habitat conditions between years. We used the binomial distribution to calculate daily and 30-day survival estimates plus 95% confidence intervals of 0.9988 ≤ 0.9997 ≤ 1.00 and 0.9648 ≤ 0.9925 ≤ 1.00, respectively. Our data indirectly support the hypothesis that hunting mortality and habitat conditions during the hunting season are the major determinants of winter survival for female mallards in Arkansas.

To increase recruitment of mallards (Anas platyrhynchos), wildlife managers must understand the habitat and space needs of mallard broods. During 1989-90, we examined the movements, home range, and habitat use of 27 radio-marked mallard broods on Lower Klamath National Wildlife Refuge, California. Twelve of the 27 broods made 22 relocation movements (>1,000 m in 24 hr) in the first week (n = 6) and after the fourth (n = 16) week of life. Mean home range size was 0.93 km2(SE = 0.25) and did not differ between years (P = 0.26). Brood-rearing females selected seasonally flooded wetlands with a cover component and avoided open or permanently flooded habitats. In 1989, broods hatched in permanent wetlands were less successful in fledging (P = 0.006) radio-marked ducklings than broods from seasonal wetlands, suggesting habitat availability or movement to preferred habitats may affect duckling survival.

Mycoplasma gallisepticum infection was diagnosed in a group of chukar partridges, pheasants, and peafowl based on serology and isolation techniques. The farm also had quail, chickens, and ducks. Clinical signs in growing birds consisted of foamy eyes, swollen infraorbital sinuses, respiratory distress, and death. Breeding birds experienced a severe drop in egg production. Histologically, the growing birds exhibited lymphoplasmacytic inflammation of the conjunctiva, sinus, and trachea. The most likely source of infection was either chickens, which had been introduced before the onset of clinical signs, or the chukar partridge breeders, which had been obtained at various hunting field trials