The effects of ground litter depth and composition on winter densities of soil-dwelling macroinvertebrates

Schuman, Gloria
Jon Atwood, PhD
Department of Environmental Studies
Macroinvertebrates were sampled from the top 15 cm of the soil surface in southern New Hampshire during winter 1999. Microhabitat variables, including soil temperature and moisture, were recorded to understand their effect on the macroinvertebrate populations. Density of macroinvertebrates was analyzed to determine if a population of the northern short-tailed shrew (Blarina brevicauda) could be supported throughout the winter months. Ten different macroinvertebrate orders were discovered. Density estimates from various samples ranged from 0 – 30518.5 individuals/m3, with a mean value of 1641.3 individuals/m3. Based on published energetic and home range requirements of short-tailed shrews, these results suggest that 2-10 shrews could be supported within 0.4 ha (one acre) of land during the winter months. Furthermore, my results suggest that shrew densities should be higher in areas where ground litter is dominated by conifer needles or a mixture of needles and hardwood tree species leaves than in areas where litter is composed entirely of hardwood leaves. More study is needed to test this prediction.

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