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Abstract. - Six sites that were sampled for alligator snapping turtles in 1993-1994 were resampled in 2009 at the same locations where previous research ers trapped. Significantly fewer alligator snapping turtles were captured per trap night at all 6 sites, and the population structure of the alligator snap ping turtles had a significantly different distribution in 2009 compared with 1993-1994. In order to continue monitoring their long-term trends in relative abun dance and population structure, future sampling of alligator snapping turtles at these 6 sites is recommended.
Long-lived organisms are difficult subjects for demographic studies because they may outlive the life span of a researcher (Reed et al. 2002). Although such studies are not frequently undertaken, they are important because the successful conservation of long-lived organ- isms depends on long-term life history research (Congdon et al. 1993, 1994; Congdon and Gibbons 1996; Congdon and Dunham 1997; Wheeler et al. 2003).
The alligator snapping turtle (Macrochelys tem- minckii) is an example of a long-lived organism that has been reduced throughout much of its range by commercial harvest (Sloan and Lovich 1995; Reed et al. 2002; Moll and Moll 2004; Pritchard 2006; Ernst and Lovich 2009). Age at first reproduction may not be achieved until at least 11-13 yrs of age (Dobie 1971) and perhaps not until 16-17 yrs of age (Tucker and Sloan 1997). Further limitations to population recovery are that females of this species may not reproduce every year (Dobie 1971; Ernst and Lovich 2009).
Riedle et al. (2005) compared presence/absence data of alligator snapping turtles in Oklahoma in 1997-2000 to the distribution based on county records from 1970. Alligator snapping turtles were trapped in only 5 counties out of the 13 counties that had historical records of the species, indicating a possibly diminishing Oklahoma distribution. While Riedle et al. (2005) demonstrated a possible shrinking of the distribution of the alligator snapping turtle in Oklahoma, a relative abundance comparison of alligator snapping turtles between 2 periods in time at specific sites remains to be explored.
In 1993, the Missouri Department of Conservation (MDC) conducted a survey of 211 trap nights that captured 21 alligator snapping turtles at 4 different sites and found 3 additional turtles at the trap sites (Santhuff 1993). MDC continued surveying...