The increase of double‐crested cormorant (Phalacrocorax auritus; hereafter, cormorant) populations during the last 2 decades has impacted many stakeholder groups. The negative effects of nesting cormorants on trees and other vegetation have motivated private organizations and government agencies to manage nesting colonies and reduce their impacts to private property and public resources. Management‐induced reproductive failure has been shown to influence cormorant inter‐annual nesting colony fidelity, but not complete abandonment from a nesting colony site. We attached very high frequency (VHF) transmitters and Global Positioning System (GPS) transmitters to nesting cormorants to monitor their movement response on a managed site (Young Island, VT [YI]) and an unmanaged site (Four Brothers Islands, NY [FB]). Additionally, we monitored these sites to determine the influence of management activities on subsequent‐year colonization. On YI, management consisted of egg‐oiling all cormorant nests (some nests had been oiled in previous years) and culling approximately 20% of adults. Annual dispersal rates did not differ between managed and unmanaged sites, but a nesting period interaction occurred with greater dispersal on the managed site following the incubation period. After 4 years of both egg oiling and culling, cormorant nesting on YI declined to zero. Simultaneously, cormorant numbers increased on the nearby unmanaged FB. We propose either the cumulative effect of partial or complete reproductive failure (8 yr) or simply the inclusion of adult culling (4 yr) caused the abandonment. From a colony‐specific management perspective, the rapid decline was beneficial to the goal of restoring the vegetative community on YI. The effects of adult culling at nesting colonies, prior‐year reproductive failure caused by egg oiling, or the combination of these factors may be required for complete and rapid nesting site abandonment. The use of culling adult breeders reduced nesting and likely limits the cost and logistics of control and allows more rapid initiation of mitigation measures and island habitat restoration. © 2011 The Wildlife Society.

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The mission of U.S. Department of Agriculture, Animal and Plant Health Inspection Service, Wildlife Services (WS) is to provide federal leadership and expertise in managing problems caused by wildlife. Approximately every 5 years, WS conducts a research needs assessment (RNA) to help to align research priorities at the National Wildlife Research Center (NWRC, the research arm of the WS program) with WS program and customer needs. In 2011, the WS Deputy Administrator solicited input from employees throughout the WS program and representatives from other federal agencies, all 50 state wildlife agencies, various livestock and agricultural commodity groups, and non-governmental organizations. Eighty-six federal employees from 36 states and the District of Columbia and 31 non-federal employees from 20 states responded to the RNA survey. Aviation safety, zoonotic diseases, livestock predation, and to a lesser degree protecting threatened and endangered (T&E) species and reducing crop depredations, were projected to be major areas of concern during the next 5 years. Invasive species, specifically feral swine, were one of the most frequently identified areas where research is needed. Development of nonlethal control methods and economic assessments were given a high priority. Many respondents wanted economic justification for their organizations or programs. Protection of aquaculture, property, and human safety, and development of vaccines and repellents were more localized concerns. Predation on livestock (especially cattle and sheep) and big game, waterfowl, and upland birds was a much bigger concern in the Western Region (WR) than the Eastern Region (ER). A higher percentage of WR respondents also anticipated being more involved in conflicts involving birds. Cormorants, beavers, deer, and especially vultures were of higher concern in the ER. State agency and private stakeholders most frequently identified either wildlife transmission of diseases or livestock depredation as their highest area of concern. State agency and private stakeholders most often identified development of more effective management techniques as their highest research priority. All respondents expressed a need for better economic information about the extent and nature of various human-wildlife conflicts. The results of this RNA, along with guidance from Congress and the WS Deputy Administrator and stakeholder input, will help establish WS research priorities.

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