| Construction projects conducted in California tiger salamander (Ambystoma californiense) upland habitat generally require minimization measures to reduce injury or mortality to individuals from ground disturbance caused by heavy equipment use. In instances where significant or prolonged ground disturbance is planned, exclusionary fencing and trapping have been used to minimize mortality of individuals in the enclosed area. Data collected at two construction sites in the East Bay in California suggest that fencing in areas near known breeding sites with large populations may require extensive biological monitoring or enhanced trapping to ensure minimal mortality during construction. At one site, trapping was conducted over many years to remove all individuals in the fenced area. However, there was no significant decline in individuals trapped per year. These data suggest that exclusionary fencing in areas with extensive underground burrow systems may have minimal effect at reducing the number of individuals in enclosed areas. At another site, a cohort of migrating juveniles was found desiccated at an exclusion fence surrounding the construction area. This example also illustrates that exclusion fencing without extensive trapping may have a detrimental effect on migrating individuals where fencing is installed close to breeding ponds.
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