Craters of the Moon National Monument And Preserve Mule Deer Survey 2002-2004

Munts, Michael

Annual mule deer survey report for 2002-04. Mule deer surveys were performed during the spring and fall of 2002 to 2004. These included unstructured spring surveys as well as the systematic fall surveys in the north end of the monument. Systematic road surveys were continued on the loop road in addition to the usual informal count during May and June. The number of does continued to decline from the previous three year period. Numbers were about a third of the 15 year average. Yearlings were also down with numbers about half of the previous three year period and the 15 year average. Over-winter survival of fawns was not calculated and reported due a very small and statistically skewed sample size. The fall survey recorded numbers that were half or less the of 15 year average for all age classes. The fawn to adult ratio continued a major decline that started in 2000. This indicates either a change in previously stable birth rates or a decline in early fawn survival. The total population estimate also showed a continued decline with estimates half to two thirds of the 15 year average. This is likely a result of drought conditions continuing through most of the period covered in this report. When the data was averaged into three year intervals the deer population shows a general pattern of decline since the mid 1980s and reaching its lowest point in the current period. The numbers of all age/sex classes showed at least small increases in 1996-1998 over the previous three year period then showed a significant decline in the years since.