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The need for alternative predator capture techniques is increasing because of concerns about the efficiency, selectivity, and injury of currently available capture methods. There also is a need for comparative data evaluating new or seldom used methods. In an initial evaluation, we first surveyed wildlife managers for information on cage-trapping; using these data, we conducted a field study of 4 coyote (Canis latrans) capture systems for animal damage management. We tested the SoftCatch®, Collarum®, Wildlife Services-Turman, and Tomahawk®, systems for capturing coyotes in Arizona and south Texas during 2001 and 2002. We determined capture efficiency and selectivity and performed whole-body necropsies to identify trap-related injuries. Surveys indicated that coyotes usually were captured in large (>1.6-m-length) cage-traps baited with meat or carcasses. In our field evaluation, we estimated a capture efficiency (percentage of coyote captures per capture opportunity) of 0% for the Tomahawk cage-trap, 87% for the Collarum, 88% for the WS-T throw arm, and 100% for the SoftCatch. Cage-traps were the least selective, capturing 34 noncoyote animals, and Collarums were the most selective, capturing no noncoyote animals. The WS-T and SoftCatch devices showed intermediate selectivity of 50% and 69%, respectively. All devices showed low injury scores relative to jawed devices in previous studies; 92%, 57%, and 92% of coyotes captured in the Collarum, WS-T, and SoftCatch showed no indicators of poor welfare, respectively. [ABSTRACT FROM AUTHOR]

A better understanding of the color vision abilities of white-tailed deer (Odocoileus virginianus) helps to determine how these animals interpret their environment. We review and summarize the literature related to the color vision abilities of white-tailed deer. Physiological measurements using advanced techniques such as molecular genetics, electroretinography, and electron microscopy have demonstrated conclusively that white-tailed deer possess the anatomical requisites for color vision. Operant conditioning techniques employed in pen studies using trained cervids confirm that deer see color. The eyes of white-tailed deer are characterized by 3 classes of photopigments: a short-wavelengthsensitive cone mechanism, a middle-wavelength-sensitive cone mechanism, and a short-wavelength-sensitive rod pigment. The number and distribution of rods and cones in the retina, augmented by adaptations of the eye, give white-tailed deer high visual sensitivity and visual acuity in light and darkness. During the day deer discriminate colors in the range blue to yellow-green and can also distinguish longer (orange and red) wavelengths. At night deer see color in the blue to blue-green range, although the moderately wide spectral sensitivity of rods permits some discrimination of longer wavelengths. Rods serve a discriminatory role in color vision, especially at Iow to moderate illumination levels. Benefits of color vision to deer include the ability to discriminate between plant species and parts and enhanced predator-detection capabilities. This information can be used to refine methods of resolving deer-human conflicts and provide insight to deer researchers, photographers... [ABSTRACT FROM AUTHOR]

Evaluates the effectiveness of two models of red laser for dispersing deer at night. Overview of deer-human conflicts; Characteristics of the eye of a deer; Reason for the differential response of birds and deer to laser light.

Presents a study that evaluated a burrow camera system for viewing and retrieving carcasses of poisoned California squirrels. Method used to control burrowing rodents in agriculture and rangelands; Advantages of using burrow-probe camera and hook system over traditional telemetry methods for finding and retrieving carcasses of poisoned rodents; Potential applications of burrow camera and hook system to other aspects of wildlife research.