Publications

Rural mail-carrier sightings of red foxes (Vulpes vulpes) during mid-April, -July, and -September of 1969-73 were compared to spring fox family estimates derived by aerial searches of six townships. The mid-April mail-carrier index reflected annual fox density changes on the six townships (correlation coefficient = 0.958) . Random exclusions of individual mail-carrier reports indicated participati

Duckling survival in wood duck (Aix sponsa) and mallard (Anas platyrhynchos) broods was estimated from data obtained from 71 radio-marked brood hens on a study area in north-central Minnesota. Radio-marked hens produced 30 broods during the study, and 41 hens already leading broods were captured and radio-marked. Production estimates based on brood size counts were inflated by about 38 percent for

Agricultural burning in an intensively farmed region within Manitoba's pothole district is shown to affect the nesting activities of ground-nesting ducks. All species, except Blue-winged Teal (Anas discors), preferred unburned nest cover, although success was higher in burned areas, where predators may have exerted less influence. Attitudes of farmers, burning chronology, and nest destruction by f

Abstract has not been submitted

Telemetry techniques were used to study habitat use and home range of 12 drake and 12 hen mallards (Anas platyrhynchos) in the forested region of north-central Minnesota during the 1968-72 breeding seasons. Circumneutral bogs and seasonal wetlands were the most frequently used communities; the lakeshore communities most used were sand-gravel, overhanging brush, and bog mat. Based on the availabili

Abstract has not been submitted

No abstract available.

Abstract has not been submitted

Open-top nest baskets were mounted on upright metal poles in various wetlands to assess the value of baskets as a potential technique for increasing duck nest success. Observations were made from 1966-1968 in North and South Dakota, Minnesota, and Wisconsin and were continued through 1973 in North Dakota. Baskets were used most readily in the prairie pothole region; of the 1,038 basket nest sites

Published techniques for fitting data to nonlinear growth curves are briefly reviewed, most techniques require knowledge of the shape of the curve. A flexible growth curve developed by Richards (1959) is discussed as an alternative when the shape is unknown. The shape of this curve is governed by a specific parameter which can be estimated from the data. We describe in detail the fitting of a dive

Abstract has not been submitted

Abstract has not been submitted