The NWRC annual performance report to 

 Congress for FY 1999 reported the Center's 

 accomplishments in meeting its goal under the 

 GPRA. The goal was to test a variety of new or 

 improved wildlife damage-management 

 methods in an effort to develop useful, 

 appropriate methods for solving wildlife 

 damage problems. 



The Center's research is organized by 

 multiyear, multidisciplinary projects that last 

 3-5 years. Project managers submit annual 

 progress reports that contain lists of studies 

 undertaken and highlight advances made by 

 the scientists. For FY 1999, NWRC reported 

 the development of 18 new or improved 

 methods to manage wildlife damage. The 

 following are examples of work by NWRC in 

 1999: 



National Trap Testing Program— This 



program to develop Best Management 

 Practices for important furbearing species 

 continues to advance. A national program is a 

 major undertaking, and participants include 

 the International Association of Fish and 

 Wildlife Agencies, 1 7 State wildlife manage- 

 ment agencies, private trappers, and two 

 Federal agencies (APHIS and the U.S. 

 Department of the Interior's U.S. Fish and 

 Wildlife Service [FWS]). Working together, 

 these agencies and organizations are 

 accomplishing the commitments made by the 

 United States to the European Union to 

 improve animal welfare in State and federally 

 sanctioned trapping programs in the United 

 States. During 1999, NWRC scientists tested 

 28 different kinds or variations of traps on 8 

 furbearing species in support of this important 

 program. 



Airport Safety— NWRC's Sandusky, OH, 

 field station continued an active research 

 program focusing on aviation hazards caused 

 by birds. 



• Biologists from the Sandusky field station, 

 in cooperation with the FAA, completed a 

 summary of all wildlife strikes to civil air- 

 craft in the United States for 1991 through 

 1997. During this 7-year period, 16,949 

 wildlife strikes were reported. Birds were 

 involved in 97 percent and mammals 

 (mostly deer) in 3 percent of the strikes. 

 The average cost per year to U.S. civil avia- 

 tion from these strikes was estimated to be 

 $315 million. Information documenting the 

 hazards of wildlife presence in airport envi- 

 ronments is critical for developing wildlife 

 hazard management plans for airports. 



• A technical paper written by NWRC for the 

 FAA on research and management programs 

 to reduce wildlife hazards at airports was 

 presented by FAA officials at the United 

 Nations Conference of the Directors of Civil 

 Aviation in Hanoi, Vietnam, in September 

 1999. The paper summarized WS research 

 and management assistance to improve 

 aviation industry safety. 



Beaver Damage Research— NWRC 

 scientists and WS wildlife specialists from 

 across the Southeast worked together in 1999 

 to develop objectives for beaver damage- 

 management research emphasizing the 

 development of methods to address regional 

 management problems. Many potential 

 improvements in existing methods and 

 strategies are under investigation. 



A wildlife biologist position was established at 

 NWRC's field station at Mississippi State 

 University to coordinate and conduct studies 

 to improve beaver impoundment water-control 

 devices and examine the feasibility of 

 frightening devices to reduce beaver activity. 

 Studies on the efficacy of textural repellants to 

 reduce beaver gnawing and tension-adjustable 

 trap triggers to reduce nontarget captures are 

 also planned. 



Aquaculture Research— Investigations of 

 problems that birds cause in the aquaculture 

 industry are the primary focus of NWRC's field 

 station at Mississippi State University. Here 

 are some examples of projects conducted in 

 1999: 



• Predation on commercial catfish stocks by 

 wading birds, primarily great blue herons 

 and great egrets, is a major threat to catfish 

 stocks. Surveys of these species revealed 

 that their populations have increased at 

 least threefold in the last 5 years. A year- 

 long field investigation by NWRC scientists 

 revealed that only 8 percent of the diet of 

 great egrets was comprised of live catfish, 

 and heron predation had a negligible impact 

 on catfish stocks. The researchers con- 

 cluded that herons were inefficient foragers 

 on healthy catfish, and that most live catfish 

 captured by herons from commercial catfish 

 farms are diseased. 



• NWRC biologists also investigated the role 

 of great blue herons as a vector of catfish 

 diseases. The findings of a cooperative 

 investigation between NWRC and the 

 Mississippi State College of Veterinary 

 Medicine indicate that wading birds are not 

 significant vectors of enteric septicemia, 

 one of the most economically significant 

 catfish diseases. 



• White pelicans have become a concern for 

 the catfish industry. Larger numbers of 

 pelicans are wintering in catfish production 

 areas, and white pelicans were recently 

 responsible for transmitting a potentially 

 serious trematode parasite to catfish stocks 

 at several fish farms in Louisiana. Impact 

 studies are continuing. 



Blackbird Damage to Rice— Redwinged 

 blackbirds and related species cause millions 

 of dollars' worth of damage to ripening rice in 

 Southeastern States during the late summer 

 and early fall. 



