Report Nr. 3093 The Kirtland's Warbler in 1988

The first Kirtland's warbler (Dendroica kirtlandii) census was organized by Harold Mayfield in 1951. The census was to be repeated every 10 years and the second census in 1961 recorded a total similar to that of 1951. The census of 1971 however revealed a precipitous drop in the population--a decline of approximately 60 percent from the 1961 count. In order to monitor the population more closely, censuses have been conducted every year since 1971. The 1988 census found 207 singing male Kirtland's warblers in Michigan, an increase of 24 percent from the 1987 count of 167. The drastic decline in census count from 210 in 1986 to 167 in 1987, and this year's dramatic increase to 215, might be construed as reason to suspect the survey's integrity. However, as noted previously, recent changes in the count appear to be habitat-related. The low count in 1987 reflects loss of birds from areas of old habitat which was not offset by gains in areas of new habitat.