1997-06-13_REPORT - M1981302 - Laserfiche WebLink

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Taper hudsoniur preblei Interim Survey Guidelines, May 27, 1997 5 5. T24ING OF SURVEY Trapping results will be considered valid only if performed within the period from June 1 to September 15. Due to the nocturnal nature of Preble's, traps should be set in the early evening and checked as early as possible in the morning (to reduce stress and the potential for predation on trapped animals). If traps must remain set during warm daylight hours and the trap has no natural shade, artificial shade should be provided. Trapping should be conducted for at least three consecutive nights if no captures occur, but may be terminated if Preble's is raptured prior to three nights. Weather is an important factor in small mammal trapping. Animals vary greatly in their behavior, activity level, and trapability depending on factors including temperature, precipitation, high winds, humidity, and moonlight. Where seasonal weather conditions have produced a poor food crop, animals may be more attracted to baits. However, conditions such as drought, severe storms, or flooding prior to the period of trapping may reduce populations through mortality, reduced reproductive success, or emigration. A thorough description of weather conditions immediately preceding and during the trapping, and of any unusual conditions prior to the period of trapping, helps validate results of trapping and could be useful in research studies on Preble's. 7. MAPS AND AERIAL PHOTOGRAPHS The Service recommends that, where available, Natural Resources Conservation Service soil maps (for location of wetland soils) and aerial photographs, National Wetlands Inventory traps, aerial city and county photographs, floodplain maps, and similar resources be consulted prior to site surveys to help identify potential habitat. Surveyors should be aware that Preble's habitat is not limited to mapped streams and wetlands. In order to avoid duplication of effort and gain more information about the ecology and distribution of Preble's, a U.S. Geological Survey (USGS) Th minute quadrangle map showing trap line transects must be submitted with the survey report (regardless of whether Preble's was located during the trapping efforts). In addition, UTM coordinates of all sites are required to facilitate data storage and utilization. For survey sites too small to be represented adequately on a USGS 71h minute quadrangle map, an engineering drawing or more detailed map showing the area that has been surveyed must be included in the report. The site(s) should be indicated and labeled on the accompanying USGS 71h minute quadrangle map. 8. ECOLOGICAL AND SITE FEATURES