THE IMPORTANCE OF NATURAL HISTORY, LANDSCAPE FACTORS, AND MANAGEMENT PRACTICES IN CONSERVING POND-BREEDING SALAMANDER DIVERSITY

I have analyzed presence, abundance, and patterns of coexistence of 11 species of pond-breeding salamanders from 203 managed sites in Indiana, Illinois, Kentucky, Michigan, and Ohio. Among these include 47 long-term sites that have been monitored for 7-15 years. The two most abundant species, Ambystoma tigrinum and A. texanum, use open habitats such as grasslands and savanna, and are found in single species communities significantly more often than expected by a null model. Several other species were more likely to coexist with certain species in assemblages, and communities of four or more species occurred significantly more often than predicted by null models. All of the sites with four or more species have fishless seasonal or semi-permanent wetlands and forested upland habitat. Among populations with long-term data, five species declined at some sites and two species increased at some sites, however, most population dynamics were apparently stable fluctuations. The declining species were primarily found in mature forest upland habitat and typically breed in fishless seasonal wetlands, whereas the increasing species use open upland habitats and semi-permanent to permanent wetlands. Regression and General Linear Models indicate that the timing of prescribed burns was a significant factor in determining the relative abundance of pond-breeding salamander larvae. Prescribed burns during spring had a negative affect on the relative abundance of nine of the 10 species that I examined; the exception was the obligate aquatic salamander Siren intermedia. The forest dwelling species took a mean of 4.6 years for populations of these species to recover to pre-burn levels. Prescribed burns also negatively affected Ambystoma tigrinum, A. texanum, and Notophthalmus viridescens, however, their mean time to recover was just 1.6 years and they typically exceeded pre-burn abundance. Conservation management practices should avoid using frequent springtime prescribed burning of wetlands and surrounding upland habitats when pond-breeding salamanders are present.