The Sandhill Cranes
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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 2009, uncorrected for visibility bias, was 460,000 sandhill cranes. The photo-corrected, 3-year average for 2006-08 was 382,271, 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 2008-09. An estimated 10,293 hunters participated in these seasons, which was similar to the number that participated in the previous season. Hunters harvested a record-high 22,989 MCP cranes in the U.S. portion of the Central Flyway during the 2008-09 seasons, which was 24% 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 15,033 during 2008-09. The preliminary estimate for the North American MCP sport harvest, including crippling losses, was 42,547 birds, which was a record high and is 7% higher than 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 2008 pre-migration survey for the Rocky Mountain Population (RMP) resulted in a count of 21,156 cranes. The 3year average for 2005, 2007, and 2008 (no survey was conducted in 2006) was 21,614 sandhill cranes, which is above the established population objective of 17,000-21,000 for the RMP. Hunting seasons during 2008-09 in portions of Arizona, Idaho, Montana, New Mexico, Utah, and Wyoming resulted in a recordhigh harvest of 946 RMP cranes, a 15% increase from the harvest of 820 in 2007-08. The Lower Colorado River Valley Population (LCRVP) survey results indicate an increase from 1,900 birds in 1998 to 2,401 birds in 2009. The 3-year average of 2,981 LCRVP cranes is based on counts from 2006, 2007 and 2009 (survey was not complete in 2008) and is above the population objective of 2,500. STATUS AND HARVESTS OF SANDHILL CRANES: MCP, RMP and LCRVP 2009 • Kruse et al.
[1] A. Leopold,et al. A Sand County Almanac and Sketches Here and There , 2020 .