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At least 829 records · Page 46Linked to original sources
USGS1988

A survey of the prevalence of selected bacteria in wild birds

We determined the prevalence of six genera of bacteria from a sample of 387 cloacal swabs from 364 passerines and woodpeckers. The prevalence of bacteria were as follows: Escherichia coli (1%), Pseudomonas spp. (22%), Salmonella spp. (0%), Staphylococcus spp. (15%), Streptococcus spp. (18%), and Yersinia spp. (1%). The prevalence of Streptococcus spp. was higher in omnivorous species than in granivorous species (20% versus 8%). Individuals captured at feeders had a lower prevalence of both Streptococcus spp. (15% versus 33%) and Escherichia coli (0.5% versus 4%) than birds that did not have access to feeders. These differences are probably not due to the feeder per se, but instead to other site related differences. The prevalence of bacteria did not differ between male and female black-capped chickadees, Parus atricapillus . For 279 color marked black-capped chickadees, we calculated the cumulative mortality rate during 12 wk following swabbing. Although the cumulative mortality rates of infected birds were consistently higher than the rates of non-infected birds, none of these differences were significant. Infections may cause slight reductions in survival rates, but we were not able to confirm this with our data.

Wisconsin↗
USGS1972

Some physiologic blood values of wild diving ducks

Blood samples were obtained from 54 canvasbacks ( Aythya valisineria ), 30 lesser scaup ( A. affinis ), 3 ring-necks ( A. collaris ), and 3 buffleheads ( Bucephala albeola ), which were wintering on Chesapeake Bay. These blood samples were used for: red blood cell counts (cans. 2.56 × 10 6 /mm 3 ; scaup 2.45 × 10 6 /mm 3 ; ring-necks 2.50 × 10 6 /mm 3 ; bufflehead 2.64 × 10 6 /mm 3 ), packed cell volume (cans. 52.2%; scaup 57.1%; ring-neck 49.1%; buffleheads 54.3%), total protein (cans. 4.4 g/100 ml; scaup 4.4 g/100 ml; ring-neck 3.5 g/100 ml; bufflehead 3.8 g/100 ml), erythrocyte measurements, and electrophoretic analysis of plasma and serum. Variations between individuals of the same species and sex were slight but a possible difference between male and female erythrocyte numbers and packed cell volumes was evident in the canvasback and scaup samples.

Maryland↗
USGS1972

Effect of certain anesthetic agents on mallard ducks

Four anesthetic agents used in human or veterinary medicine and 3 experimental anesthetic preparations were evaluated for effectiveness in inducing narcosis when administered orally to game-farm mallard ducks (Anas platyrhynchos).Tribromoethanol was the only compound to satisfy criteria of initial tests. Mean duration of the induction, immobilization, and recovery periods was 2.4 minutes, 8.7 minutes, and 1.3 hours, respectively, at the median effective dosage for immobilization (ED50; 100 mg./kg. of body weight). The median lethal dosage (LD50) was 400 mg./kg. of body weight.Tribromoethanol was also tested on mallards during the reproductive season. Effects on the hatchability of eggs or the survival of young were not detected.

Journal of the American Veterinary Medical Associa↗
USGS1983

Aspergillosis in a red-crowned crane

An unusual form of pulmonary aspergillosis in a red-crowned crane ( Grus japonensis ) is described in this report. The major lesion is unique because it closely resembles a lesion referred to as an aspergilloma. An aspergilloma is a single large granulomatous lesion that resembles a tumor and is caused by fungi of the genus Aspergillus.

Wisconsin↗
USGS1986

Winter distribution and oiling of common terns in Trinidad: A further look

Common Terns were studied during January and March 1985 in Trinidad as part of wintering terns in Latin America. Eighty-nine birds were captured, 33 in January, 56 in March. Terns averaged 102 .+-. 0.9 g, with March birds weighing more than those caught in January. This weight is similar to that reported earlier by Blokpoel et al. (1982, 1984) and is considerably less than weights of either premigratory immature or adult Common Terns. Terns in Trinidad appear to be opportunistic, using human fishing for their food source and roosting on boats, oil platforms and other man-made structures. One-half of the captured sample of birds had at least detectable amounts of oil on the plumage. This represents the highest frequency of oiling reported yet for any seabird living under 'baseline' (non-spill) conditions in North or Central America. Oiling had no apparent major effect on the condition of birds since oiled birds had similar weights and blood parameters when compared to unoiled birds.

Journal of Field Ornithology↗
USGS1984

Breeding biology of the blue-gray noddy

Blue-gray Noddies, the smallest marine terns, are similar in many respects to all tropical terns in Hawaii: single-egg clutches are laid, growth and development take about 7 weeks, breeding is colonial. Its small size results in eggs that comprise over 27% of adult body weight, compared to 15-20% for most marine terns (Langham 1983). Blue-gray Noddies are widespread in the tropical Pacific, but populations are generally small. This may be the result of its inshore feeding habits and the fact that it is a resident species (Diamond 1978). However, populations in the Hawaiian Archipelago are probably limited by the availability of suitable nest sites in cliffs or rocky outcrops, not food supplies..... Food habits in Hawaii confirm the unique dependence of this species on sea-striders but consumption may be seasonal Blue-gray Noddies take the smallest prey of any seabird in Hawaii and may feed on a lower trophic level..... The Hawaiian population is apparently heavier and produces larger eggs than Blue-gray Noddies elsewhere in the Pacific. This conforms with the general proposition that Hawaiian seabirds are larger than those in the central Pacific (Harrison et al. 1983). The Hawaiian population also has a more predictable breeding season than those farther south.This may be due to a greater seasonality of food supply, but the factors that control the timing of breeding are not clear. There does not appear to be any competition for nest sites with other seabirds.....Our information on growth and development will enable future investigators to estimate the ages of chicks during brief visits to Blue-gray Noddy colonies. This will facilitate programs that are designed to monitor the basic health of seabird populations and to detect changes from baseline that may result from human activities or oceanographic conditions.

Journal of Field Ornithology↗
USGS2003

Biorecovery of gold

Recovery of ionic and metallic gold (Au) from a wide variety of solutions by selected species of bacteria, yeasts, fungi, algae, and higher plants is documented. Gold accumulations were up to 7.0 g/kg dry weight (DW) in various species of bacteria, 25.0 g/kg DW in freshwater algae, 84.0 g/kg DW in peat, and 100.0 g/kg DW in dried fungus mixed with keratinous material. Mechanisms of accumulation include oxidation, dissolution, reduction, leaching, and sorption. Uptake patterns are significantly modified by the physicochemical milieu. Crab exoskeletons accumulate up to 4.9 g Au/kg DW; however, gold accumulations in various tissues of living teleosts, decapod crustaceans, and bivalve molluscs are negligible.

Indian Journal of Experimental Biology↗
USGS2006

Comment on 'Are survival rates for northern spotted owls biased?'

Loehle et al. recently estimated survival rates from radio-telemetered northern spotted owls (Strix occidentalis caurina (Merriam, 1898)) and suggested that survival rates estimated for this species from capture-recapture studies were negatively biased, which subsequently resulted in the negatively biased estimates of rates of population change (lambda) reported by Anthony et al. (Wildl. Monogr. No. 163, pp. 1-47 (2006)). We argue that their survival estimates were inappropriate for comparison with capture-recapture estimates because (i) the manner in which they censored radio-telemetered individuals had the potential to positively bias their survival estimates, (ii) their estimates of survival were not valid for evaluating bias, and (iii) the size and distribution of their radiotelemetry study areas were sufficiently different from capture-recapture study areas to preclude comparisons. In addition, their inferences of negative bias in rates of population change estimated by Anthony et al. were incorrect and reflected a misunderstanding about those estimators.

Canadian Journal of Zoology↗
USGS2006

Multistate survival models and their extensions in Program MARK

Program MARK provides .100 models for the estimation of population parameters from mark?encounter data. The multistate model of Brownie et al. (1993) and Hestbeck et al. (1991) allows animals to move between states with a probability of transition. The simplest multistate model is an extension of the Cormack?Jolly?Seber (CJS) live recapture model. arameters estimated are state-specific survival rates and encounter probabilities and transition probabilities between states. The multistate model provides a valuable framework to evaluate important ecological questions. For example, estimation of state-specific survival and transition probabilities between the biological states of breeders and nonbreeders allows estimation of the cost of reproduction. Transitions between physical states, such as spatial areas, provide estimates needed for meta-population models. The basic multistate model uses only live recaptures, but 3 extensions are included in MARK. A multistate model with live and dead encounters is available, although the dead encounters are not state specific. Robust-design multistate models are also included in MARK, with both open and closed robust designs. These models assume that animals move between states only between primary sessions of the robust design. For the closed robust design, we can specify 12 different data types for the modeling of encounter probabilities during the primary session, including 6 versions of the closed model likelihood incorporating population size (N) directly in the likelihood, and 6 versions of the Huggins model in which N is estimated as a derived parameter outside the likelihood. One assumption that is generally necessary to estimate state-specific survival rates in the multistate model is that transitions take place immediately before encounter occasions. Otherwise, survival rates over the interval between encounter occasions are a mix of survival rates over multiple states. Advantages of using MARK to estimate the parameters of the various multistate models include flexibility of model specification to include group, time, and individual covariates, estimation of variance components, model averaging of parameter estimates, and Bayesian parameter estimation using Markov chain Monte Carlo procedures on the logit scale.

Journal of Wildlife Management↗