scholarly journals Survival Rates and Stopover Persistence of American Woodcock Using Cape May, New Jersey, during Fall Migration

The Condor ◽  
2020 ◽  
Author(s):  
Brian B Allen ◽  
Daniel G McAuley ◽  
Erik J Blomberg

Abstract Migration is a period of high activity and exposure during which risks and energetic demand on individuals may be greater than during nonmigratory periods. Stopover locations can help mitigate these threats by providing supplemental energy en route to the animal’s end destination. Effective conservation of migratory species therefore requires an understanding of use of space that provides resources to migratory animals at stopover sites. We conducted a radio-telemetry study of a short-distance migrant, the American Woodcock (Scolopax minor), at an important stopover site, the Cape May Peninsula, New Jersey. Our objectives were to describe land-cover types used by American Woodcock and evaluate home range habitat selection for individuals that stopover during fall migration and those that choose to overwinter. We radio-marked 271 individuals and collected 1,949 locations from these birds (0–21 points individual–1) over 4 yr (2010 to 2013) to inform resource selection functions of land-cover types and other landscape characteristics by this species. We evaluated these relationships at multiple spatial extents for (1) birds known to have ultimately left the peninsula (presumed migrants), and (2) birds known to have remained on the peninsula into the winter (presumed winter residents). We found that migrants selected deciduous wetland forest, agriculture, mixed shrub, coniferous wetland forest, and coniferous shrub, while wintering residents selected deciduous wetland forest, coniferous shrub, and deciduous shrub. We used these results to develop predictive models of potential habitat: 7.80% of the peninsula was predicted to be potential stopover habitat for American Woodcock (95% classification accuracy) and 4.96% of the peninsula was predicted to be potential wintering habitat (85% classification accuracy). Our study is the first to report habitat relationships for migratory American Woodcock in the coastal U.S. and provides important spatial tools for local and regional managers to support migratory and winter resident woodcock populations into the future.


1997 ◽  
Vol 61 (4) ◽  
pp. 1328 ◽  
Author(s):  
David G. Krementz ◽  
James B. Berdeen

1994 ◽  
Vol 58 (1) ◽  
pp. 147 ◽  
Author(s):  
David G. Krementz ◽  
John T. Seginak ◽  
David R. Smith ◽  
Grey W. Pendleton

1996 ◽  
Vol 74 (11) ◽  
pp. 2046-2054 ◽  
Author(s):  
Jerry R. Longcore ◽  
Daniel G. McAuley ◽  
Greg F. Sepik ◽  
Grey W. Pendleton

We radio-marked 150 male American woodcock (Scolopax minor) during 1987–1989 and estimated period survival for 1 April – 15 June. Survival varied from 0.690 (1989) to 0.924 (1988), with a 3-year mean (95% confidence interval) of 0.789 (0.693–0.885). Woodcock were killed by raptors (n = 14, 53.8%), mammals (n = 1, 3.8%), or unknown predators (n = 5, 19.2%); six deaths (23.1%) were from miscellaneous causes, including three (11.5%) from entanglement in the transmitter harness. A composite survival estimate based on telemetry studies for the breeding, postbreeding, and wintering periods was 0.471 (0.789 × 0.923 × 0.647). The calculated survival rates were 0.881 for the spring migration period and 0.853 for the combined hunting and fall migration period. In a proportional hazards model, body mass at capture was not related to survival. Forest type (hardwood versus conifers) affected survival (P < 0.016), which was lower for woodcock using mostly conifer sites. Survival was related positively to mean snow depth in December (P < 0.038), negatively to snow depth in April (P < 0.046), and positively to minimum temperature in December (P < 0.054) and April (P < 0.066) in some analyses.


Author(s):  
K. Shankar Narayan ◽  
Kailash C. Gupta ◽  
Tohru Okigaki

The biological effects of short-wave ultraviolet light has generally been described in terms of changes in cell growth or survival rates and production of chromosomal aberrations. Ultrastructural changes following exposure of cells to ultraviolet light, particularly at 265 nm, have not been reported.We have developed a means of irradiating populations of cells grown in vitro to a monochromatic ultraviolet laser beam at a wavelength of 265 nm based on the method of Johnson. The cell types studies were: i) WI-38, a human diploid fibroblast; ii) CMP, a human adenocarcinoma cell line; and iii) Don C-II, a Chinese hamster fibroblast cell strain. The cells were exposed either in situ or in suspension to the ultraviolet laser (UVL) beam. Irradiated cell populations were studied either "immediately" or following growth for 1-8 days after irradiation.Differential sensitivity, as measured by survival rates were observed in the three cell types studied. Pattern of ultrastructural changes were also different in the three cell types.


1999 ◽  
Vol 63 (12) ◽  
pp. 969-975 ◽  
Author(s):  
WR Cinotti ◽  
RA Saporito ◽  
CA Feldman ◽  
G Mardirossian ◽  
J DeCastro

Sign in / Sign up

Export Citation Format

Share Document