Old 09-15-2014, 03:59 PM
Typical Buck
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Join Date: Jun 2005
Location: Weatherford, TX
Posts: 557
Default Fawn Recruitment studies/predator management

Been doing some research for hard data for advertising purposes and was really surprised at what I found in the way of information derived from studies, for those of you that own land, or lease land for hunting should really look at these numbers, they might surprise you..

L. Mike Connor – Joseph W. Jones Ecological Research Center; Michael J.
Cherry – University of Georgia; Keri E. Morgan – University of Georgia;
Brandon T. Rutledge – Joseph W. Jones Ecological Center; Robert J. Warren –
University of Georgia Department of Natural Resources

ABSTRACT: Increasingly researchers acknowledge that non-consumptive predator-prey interactions can have profound effects. We propose that coyote effects on deer may transcend direct mortality and that the non-consumptive interactions and their implications for deer populations and habitats should be investigated. We used a combination of monitoring data and experimentation to evaluate the potential for non-consumptive effects of coyotes on deer
nutritional condition, reproductive strategy, and herbivory patterns on the Jones Ecological Research Center, in southwestern Georgia. We predicted harvest weights of 466 adult does from an 11 year period, and using an information theoretic approach we found support for the effects of predation risk and individual attributes , evidence of lactation , but not resource availability. To evaluate the effects of predation risk on reproductive fitness we measured ovulations rates of does during a coyote decline. We found that during low coyote abundance, ovulation rates were 1.7 times greater than during high coyote abundance ,despite increased deer abundance and similar nutritional condition. Increased recruitment was better explained by ovulation rates than survival rates of marked fawns. We previously demonstrated predator exclusion influenced deer foraging and therefore we measured the
abundance of 10 selected browse species in predator exclosures and controls. Selected browse species were 1.3 times more abundant in controls . We suggest coyotes may have substantial non-consumptive effects on deer and their habitats in the Southeast, and that future research should investigate these interactions.

Fawn recruitment/vs predator studies

Georgia, researchers used trail cameras to survey fawn-to-doe ratios in two study areas 2.5 miles apart. They removed 23 coyotes and three bobcats from January to August in an 11,000-acre area, but removed no predators from a nearby 7,000-acre block.

Shortly before hunting season, their camera census estimated 0.72 fawns per doe where predators were killed, and 0.07 fawns per doe where no predators were killed. Translation: Two fawns were present for every three does in the predator-removal area, and two fawns were present for every 28 does where no predators were killed.

South Carolina, a 3-year study at the U.S. Forest Service's Southern Research Station on the 300-square-mile Savannah River Site found only 16 of 60 radio-collared fawns lived past nine weeks, a 27 percent survival rate. Most deaths occurred within five to six weeks of birth. Specifically, 16 (36 percent) died the first week; 26 (59 percent) died between week two and week six; one died in week seven; and one died in week nine. In other words, if two does gave birth to twins, by Labor Day they had one fawn between them.

Researchers attributed only 13 percent (five) of those 44 deaths to bobcats. They confirmed coyotes as the predator in 65 percent of the deaths, the probable predator in 15 percent of the deaths and the most likely predator in 5 percent of the deaths. Therefore, coyotes were likely responsible for about 38 (85 percent) of the 44 dead fawns

Alabama, a two-year study on 2,000 acres convinced researchers that coyotes were a limiting factor in the number of fawns "recruited" into the herd. Two findings guided their conclusion: First, laboratory analysis of coyote scat and stomach contents showed fawns made up 27.3 percent of the coyotes' July-to-September diet, the region's peak fawning months. Although small mammals (rabbits and rodents) also formed 27.3 percent of the summer diet, fawn meat was found more important because of its higher nutritional value. Second, the researchers documented a staggering jump in fawn abundance after trappers removed 22 coyotes and 10 bobcats between February and July 2007.

Data from observations showed a fawn/doe ratio of 0.52 before the trapping program, and 1.1 after the removals. Similarly, a network of Web-equipped cameras showed 0.52 fawns per doe before removal and 1.33 afterward. Combined, that's a 190 percent increase in fawn-to-doe ratios.


Last edited by Tuffbroadhead; 09-15-2014 at 07:23 PM.
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