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Full-Text Articles in Ornithology
Geographic Segregation And Evidence Of Density-Dependent Changes In Sex Ratios In An Abundant Colonial Waterbird, Brian S. Dorr, Katie C. Hanson-Dorr, Travis L. Devault, Alban Guillaumet, Scott C. Barras
Geographic Segregation And Evidence Of Density-Dependent Changes In Sex Ratios In An Abundant Colonial Waterbird, Brian S. Dorr, Katie C. Hanson-Dorr, Travis L. Devault, Alban Guillaumet, Scott C. Barras
Brian S Dorr
Demographic information, such as geographic segregation of sexes and sex ratio data, is needed to develop, model and evaluate conservation and management strategies for wildlife. A variety of physiological, behavioral and environmental factors can influence segregation of sexes and sex ratios, many of which originate with density- dependent processes. Departure from 50:50 sex ratios of double-crested cormorants (Phalacrocorax auritus) collected during control efforts in breeding and wintering areas across their eastern range of the USA were evaluated using using a Z-test as well as Stouffer’s weighted Z-tests. In addition, a specifically-designed randomization test was used to evaluate density-dependent effects on …
A New Policy For Management Of Double-Crested Cormorants In The United States And An Example Of Its Implementation., Shauna L. Hanisch, Brian S. Dorr, Peter H. Butchko
A New Policy For Management Of Double-Crested Cormorants In The United States And An Example Of Its Implementation., Shauna L. Hanisch, Brian S. Dorr, Peter H. Butchko
Brian S Dorr
In the fall of 2003, the U.S. Fish and Wildlife Service (USFWS), in cooperation with USDA-Wildlife Services (USDA-WS), completed an Environmental Impact Statement (EIS) for the management of Double-crested Cormorants (DCCOs) in the United States. The USFWS subsequently published new regulations to implement the EIS proposed strategy. One part of the new regulations, a “public resource depredation order” (PRDO), allows state wildlife agencies, tribes, and USDA-WS to control DCCOs on a localized level to protect fish, wildlife, plants, and their habitats in 24 states. We’ll discuss this new policy and will highlight the management activities, including monitoring and evaluation efforts, …
Evaluation Of Plastic And Mylar Flagging As Repellents For Snow Geese (Chen Caerulescens), J. Russell Mason, Larry Clark
Evaluation Of Plastic And Mylar Flagging As Repellents For Snow Geese (Chen Caerulescens), J. Russell Mason, Larry Clark
Larry Clark
The effectiveness of white flags, black flags and Mylar streamers as visual repellents to snow geese (Chen caerulescens) was evaluated. Five farms in Cumberland and Salem counties, New Jersey served as test sites. At each farm, four 10.12 ha fields were selected randomly, and then assigned to four treatment conditions: (a) white plastic flags (one flag per 0.4 ha); (b) black plastic flags (one flag per 0.4 ha), (c) Mylar streamers (one streamer per 0.4 ha); and (d) stakes only (one stake per 0.4 ha). From 2 December 1992 to 24 March 1993, vegetation samples and goose droppings were collected …
Use Of Activated Charcoal And Other Particulate Substances As Feed Additives To Suppress Bird Feeding, J. Russell Mason, Larry Clark
Use Of Activated Charcoal And Other Particulate Substances As Feed Additives To Suppress Bird Feeding, J. Russell Mason, Larry Clark
Larry Clark
Osmotic strength is a function of particle number. The experiments described here were designed to test whether the consumption of a large number of small particles might induce strong osmotic effects that, in turn, could induce food avoidance learning. The experiments also evaluated whether the abrasiveness of fine particulates or their ability to act as organic adsorbants could mediate or contribute to the avoidance of adulterated diets. In experiment I. captive European starlings (Sturnus vulgaris) were given two-cup tests between plain chow and chow adulterated with activated charcoal or Anjan-activaid. a product containing large amounts of activated charcoal. Both adulterants …