Herpetofaunal Surveys of National Park Service Sites in Western Nebraska, Eastern Wyoming, Western South Dakota, and Western North Dakota: Interim Report, 2002 Field Work

Smith, Brian

During spring and summer of 2002, surveys of seven national park units were conducted in western Nebraska, eastern Wyoming, western South Dakota, and western North Dakota. The objectives were to assess various survey techniques used in the area, including visual encounter surveys, nighttime call surveys, night driving and trail searches, and nighttime searches of prairie dog burrows. Drift fences were not used. The most successful techniques were nighttime call surveys and nighttime searches of prairie dog burrows, but both survey types are biased towards the observation of only one or a few species of amphibians. Visual encounter surveys were the only other survey type that was successful in finding other species, but in general the success rate of this survey type was very low (but higher when conducted in suitable habitat than if they were conducted at random localities). Few expected species have been encountered on each park unit. Possible reasons for this included the lack of use of some survey types, especially drift fences, severe drought affecting the area in 2002, and lack of time and resources. It is also possible that the numbers of species of herpetofauna expected on each park will decline when detailed reports are compiled in which habitat is taken into consideration. Suitable habitat for several species does not exist on many of the park units under investigation, although these species are listed as occurring on the park unit since the unit is within the range of the species.

Herpetofaunal Surveys of National Park Service Sites in Western Nebraska, Eastern Wyoming, Western South Dakota, and Western North Dakota: Interim Report, 2002 Field Work

Collections