Site Preparation Drives Long-Term Plant Community Dynamics in Restored Tallgrass Prairie: A Case Study in Southeastern South Dakota.

Most tallgrass prairies have been destroyed or altered, making restoration an important component to their conservation. Our goal was to evaluate progress 12-years post-restoration at Spirit Mound Historic Prairie and determine whether the outcomes varied based on different land use and restoration histories across the site. We examined changes in plant diversity, richness, evenness, non-native species relative abundance, and community composition from 2004 to 2013. Areas with different restoration treatments and land-use histories showed divergent results. Seventy percent of the site, previously annual row crop, was reconstructed using herbicide application followed by native seeding (hereafter reconstruction). Areas that were previously grazed, 15 % of the site, were restored with only partial seeding and no herbicide treatment (hereafter rehabilitation). Species richness and diversity increased over 40 % in the reconstruction since 2004 and remained over 1.9 times higher in the reconstructed areas than rehabilitated areas. Diversity did not change in the rehabilitation, but richness increased 47 % since 2004. Evenness decreased 11-26 % over time in both areas. Non-native species relative abundance did not change from 2004 to 2013, and remained five times higher in the rehabilitation than the reconstruction. Native C4 grass and forb abundance increased over time in the reconstruction, whereas non-native C3 grasses remained dominant in the rehabilitation. These results showed that restoration outcomes were radically different 12-years post-restoration among areas with different prior land uses that were subjected to different restoration practices. Long-term assessments are important to accurately determine restoration progress and inform management decisions.

PREVALENCE OF RANAVIRUS IN SPOTTED SALAMANDER (AMBYSTOMA MACULATUM) LARVAE FROM CREATED VERNAL POOLS IN WEST VIRGINIA, USA.

Ranavirosis is a disease of high concern for amphibians due to widespread documentation of its lethal and sublethal impacts and its high transmission potential across populations and species. We investigated whether spotted salamander (Ambystoma maculatum) ranavirus prevalence and viral load were associated with habitat characteristics, genetic diversity, corticosterone levels, and body size. In 2015 and 2016, we sampled 34 recently created vernal pools in the Monongahela National Forest, West Virginia, USA. We collected tail clippings from 1,128 spotted salamander larvae and waterborne hormone samples from 436 of those larvae, along with eight environmental characteristics of the pools. Over the 2-yr period, we detected ranavirus in 62% of pools, with prevalence ranging from 0% to 63% (mean, 7.68%). Spotted salamander size was positively correlated with ranavirus presence and viral load; however, we did not find associations between ranavirus prevalence or viral load and habitat characteristics, spotted salamander genetic diversity, relatedness, effective number of breeders, or corticosterone levels. The widespread occurrence of ranavirus in the vernal pools illustrates the potential for rapid natural introduction of the pathogen to created wetlands. Managers could consider monitoring local distributions of ranavirus before creation of new vernal pools to guide strategic placement of the wetlands to minimize occurrence and prevalence of this pathogen.

Water-borne and plasma corticosterone are not correlated in spotted salamanders.

Water-borne hormone measurement is a noninvasive method suitable for amphibians of all sizes that are otherwise difficult to sample. For this method, containment-water is assayed for hormones released by the animal. Originally developed in fish, the method has expanded to amphibians, but requires additional species-specific validations. We wanted to determine physiological relevance of water-borne corticosterone in spotted salamanders (Ambystoma maculatum) by comparing concentrations to those taken using established corticosterone sampling methods, such as plasma. Using a mixture of field and laboratory studies, we compared water-borne corticosterone levels to other traditional methods of sampling corticosterone for spotted salamander larvae, metamorphs, and adults. Despite multiple attempts, and detecting differences between age groups, we found no correlations between water-borne and plasma corticosterone levels in any age group. Water-borne sampling measures a rate of release; whereas plasma is the concentration circulating in the blood. The unique units of measurement may inherently prevent correlations between the two. These two methods may also require different interpretations of the data and the physiological meaning. We also note caveats with the method, including how to account for differences in body size and life history stages. Collectively, our results illustrate the importance of careful validation of water-borne hormone levels in each species in order to understand its physiological significance.