US Fish & Wildlife Service
STATUS AND HARVESTS OF SANDHILL CRANES: MID-CONTINENT, ROCKY MOUNTAIN and LOWER COLORADO RIVER VALLEY POPULATIONS 2008
Date of this Version
Kruse, K.L., D.E. Sharp, and J.A. Dubovsky. 2008. Status and harvests of sandhill cranes: Mid- Continent, Rocky Mountain and Lower Colorado River Valley Populations. Administrative Report, U.S. Fish and Wildlife Service, Denver, Colorado. 11pp.
Compared to increases recorded in the 1970s, annual indices to abundance of the Mid-Continent Population (MCP) of sandhill cranes have been relatively stable since the early 1980s. The Central Platte River Valley, Nebraska, spring index for 2008, uncorrected for visibility bias, was 472,128 sandhill cranes. The photo-corrected, 3-year average for 2005-07 was 364,281, which is within the established population-objective range of 349,000-472,000 cranes. All Central Flyway States, except Nebraska, allowed crane hunting in portions of their States during 2007-08. About 9,808 hunters participated in these seasons, which was similar to the number that participated in the previous season. Hunters harvested 18,610 MCP cranes in the U.S. portion of the Central Flyway during the 2007-08 seasons, which was 6% higher than the estimated harvest for the previous year. The retrieved harvest of MCP cranes in hunt areas outside of the Central Flyway (Arizona, Pacific Flyway portion of New Mexico, Alaska, Canada, and Mexico combined) was 13,567 during 2007-08. The preliminary estimate for the North American MCP sport harvest, including crippling losses, was 36,567 birds, which is similar to the previous year’s estimate. The long-term (1982-2004) trends for the MCP indicate that harvest has been increasing at a higher rate than population growth. The fall 2007 premigration survey for the Rocky Mountain Population (RMP) resulted in a record high count of 22,822 cranes. The 3-year average for 2004, 2005, and 2007 (no survey was conducted in 2006) was 20,732 sandhill cranes, which is within established population objectives of 17,000-21,000 for the RMP. Hunting seasons during 2007-08 in portions of Arizona, Idaho, Montana, New Mexico, Utah, and Wyoming, resulted in a harvest of 820 RMP cranes, a 10% decrease from the harvest of 907 the year before. The Lower Colorado River Valley Population (LCRVP) survey results suggested an increase from 1,900 birds in 1998 to 2,772 birds in 2007; an average growth rate of approximately 3% per year for that time frame. In 2007, the Service determined that a small allowable harvest of 32 cranes could be allowed following guidelines from the management plan, but a hunt was not conducted.