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Catherine Frazer

Publications and source records attributed to Catherine Frazer.

3 recordsLinked to original sources

Survival of postfledging female American black ducks

We equipped 106 hatching-year (HY), female, black ducks ( Anas rubripes ) with transmitters during 1985-87 and monitored survival from late August to mid-December on a lightly hunted area on the Maine-New Brunswick border. The 1985-87 estimate of survival (hunting losses included) was 0.593, and when losses from hunting were censored it was 0.694. Survival in August-September was 0.987; by 31 October survival declined to 0.885, and by 30 November it was 0.718. Most nonhunting mortality was caused by predators (21/41, 53.2%); there were 14 deaths (34.1%) from mammals or unknown predators and 7 (17.1%) from raptors. Hunting caused 13 (31. 7%) deaths. Ducks with lowest mass had the lowest survival. The estimate of survival for postfledging female black ducks, when multiplied with interval survival rates for hunting, winter, and breeding periods, produced an annual survival estimate of 0.262, about 12% lower than that (0.38) based on analysis of banding data.

Maine

Home range and movements of postfledging American black ducks in eastern Maine

We monitored the movements of 97 female and 15 male juvenile American black ducks (Anas rubripes) in the vicinity of Moosehorn National Wildlife Refuge in eastern Maine and southwestern New Brunswick from September through mid- December, 1985-1987.. Movements were described by estimating home ranges and radial movements from the primary roost marsh. Overall home range sizes averaged 4987 ha (range 54 - 28 070 ha), and maximum distances moved from the roost averaged 9.9 km (range 0.9-42.8 km). Home ranges were linear (linearity index 2.8), and home range area and distance of movements from the roost both increased monthly. Ducks that used >15 % riverine habitat had larger home ranges and moved greater distances from the roost than ducks using <15% riverine wetlands. Movements did not differ between ducks usually alone and those usually in flocks. Juvenile black ducks moved in small flocks and were often alone (34% of 355 observations). Most ducks showed fidelity to one roost-marsh complex from September until migration in late November. Daily and seasonal movement patterns were similar to those predicted for refuging systems.

Canadian Journal of Zoology

Habitat use by postfledging American black ducks in Maine and New Brunswick

We examined habitat use by 112 postfledging American black ducks ( Anas rubripes ) in eastern Maine and southwestern New Brunswick from September through early December of 1985, 1986, and 1987. Ducks were captured on Moosehorn National Wildlife Refuge (NWR), Maine. Palustrine Emergent Wetland was the most preferred habitat type. Riverine habitats were avoided in September, but were used more than, or in proportion to, their availability in November as ice formed on lentic habitats. Black ducks used a greater variety of habitat types during the day than at night, when ducks used mostly large (>30 ha) Emergent Wetland marshes. Managed impoundments of Moosehorn NWR were the most used wetlands (66% of all diurnal, 90% of all nocturnal locations). For black duck management, we propose maintaining large (30-50 ha) marshes containing dense emergent vegetation that are located near a complex of diverse wetland types.

Maine