Date of this Version
During the last six years the N.Y. Coop. Wildlife Research Unit has been involved in research on pine voles. Projects have included studies of reproduction in the laboratory, population biology in orchards and testing of pine vole control toxicants. Field work has been restricted to a few orchards in Ulster and Orange counties in the Hudson Valley. Therefore some of the results may reflect local conditions and should be regarded as preliminary in nature. Work involving control procedures has indicated that hand baiting with anticoagulant pellets under previously established bait stations averages 85 percent reduction in pine vole numbers. Anticoagulant ground sprays average 60 percent reduction in numbers under good conditions. As we see it, three major problems in control procedures remain to be solved. First, orchard managers and available labor must learn to properly place bait stations and baits. Second, optimal timing and frequency of bait application must be determined. Third, and perhaps the largest oversight in the work to date, is that the relationship between a reduction in pine vole numbers and the reduction in apple tree damage must be established. These last two points viewed in a broader context confirm the need to develop an integrated pest management strategy. Its objective is to provide the orchard manager with the information needed to weigh the cost and predicted benefit of a specific control procedure. The optimal method and timing of control can be determined by computer simulation. The data input necessary to do this falls into two broad categories: factors affecting vole numbers and factors affecting the degree of tree damage for a given number of voles.