Oral Abstract Details

Author(s):
Robert F. Baldwin

Affiliation:
Clemson University

Presentation Type:
Oral

Topic Area:
Application of ecological research in land-use planning

Abstract Text:
Amphibians are in global decline and many of their wetland habitats are under-protected by land conservation efforts and government regulation. Pool-breeding amphibians are dependent upon wetlands for breeding and frequently move long distances to adjacent habitats to fulfill other life history needs. Consequently, conservation planning for pool-breeding amphibians has focused on defining functional habitat patches for local populations that includes wetlands and surrounding habitats. Recent advances for setting conservation priority using spatial models have taken into account three primary factors, (1) habitat patches, (2) landscape resistance, and (3) changing land uses. Landscape resistance is particularly important component of habitat conservation models for pool-breeding amphibians because of their seasonal migrations between breeding pools and adjacent habitats used for foraging, hibernation, and maintaining water balance. This study compares two recently published approaches to wetland conservation designed to prioritize pools and associated habitats: threat analysis and resistant kernels. I compare model assumptions, data sources, outputs, and conservation implications for a single study area. Threat analysis incorporates potential habitat modified by landscape resistance derived from fine-scale land use/land cover data, development pressure derived from US Census data, and levels of current land protection. Resistant kernels incorporate density of wetland habitats and degree of connectivity among them due to landscape resistance. I employed the same habitat and landscape resistance data for both models. Nearly half of the study area (46%) had exactly the same outputs for threat analysis and resistant kernel (difference = 0) and 80% of the landscape had very similar outputs (difference between outputs -1> <+1). Because the models were run using the same data inputs, differences between the outputs were attributed to model structure and assumptions. Several of the areas with the strongest negative difference values (resistant kernels were identified, but areas of high threat were not) were on lands already protected by easements and other conservation mechanisms. Threat analysis emphasizes priority for lands having a combination of high habitat value, strong pressure for conversion to development, and lack of current protection. Resistant kernels cluster habitats for protection based on density and connectivity but do not take into account future threats. Thus, threat analysis outputs were more inclusive than resistant kernels as 97% of the differences were neutral or positive. While differences were slight, it is important to engage stakeholders in the modeling process so they understand how assumptions influence conservation outcomes. Priority setting models may be especially useful for seasonal woodland pools that are under-protected by wetland regulations and thus require attention by land trusts and other local conservation efforts.