Objectives What is a metapopulation? Case study using 2 species of Ambystoma salamanders Example management tool for increasing connectivity
Metapopulation Dynamics What is a metapopulation? A population of populations that exchange migrants
Metapopulation Dynamics What is a metapopulation? A population of populations that exchange migrants Source Populations Sink Populations Mainland Island Patchy PopulationsSource – Sink
Why are metapopulations important? Elucidate spatial structure of populations/species distributions Usage of habitat types Which are utilized How are they utilized Which habitats are most important Allows us to determine where to focus management efforts Enhance persistence of species Allow mitigation in relationship to military training and readiness
What is connectivity “… the degree to which the landscape facilitates or impedes movement among resource patches.” Taylor et al. 1993
What is connectivity? “… the degree to which the landscape facilitates or impedes movement among resource patches.” Structural Connectivity Functional Connectivity Taylor et al. 1993; Brooks 2003; Taylor et al. 2006
Why is connectivity important? Measures dispersal Genetics allows you to see movement between A & B
Why is connectivity important? Measures dispersal Genetics allows you to see movement between A & B Understand spatial dynamics Panmictic population? Multiple populations? Independent populations?
Why is connectivity important? Measures dispersal Genetics allows you to see movement between A & B Understand spatial dynamics Panmictic population? Multiple populations? Independent populations? Important tool for effective management and conservation Genetic surveys are first step of any species listing process
Case Study: Fort Leonard Wood, MO N = 500 ponds; 24,686 hectares Focal Area 7,140 hectares N ~ 200 ponds
A. maculatum Spotted A. annulatum Ringed
A. maculatum Spotted A. annulatum Ringed Fall Breeding Sept/Oct – April/May
A. maculatum Spotted A. annulatum Ringed Fall Breeding Sept/Oct – April/May Overwintering Larvae
A. maculatum Spotted A. annulatum Ringed Fall Breeding Sept/Oct – April/May Overwintering Larvae Semi-permanent Ponds
A. maculatum Spotted A. annulatum Ringed Fall Breeding Sept/Oct – April/May Overwintering Larvae Semi-permanent Ponds Spring Breeding Feb/March – June/July
A. maculatum Spotted A. annulatum Ringed Fall Breeding Sept/Oct – April/May Overwintering Larvae Semi-permanent Ponds Spring Breeding Feb/March – June/July Seasonal Ponds
A. maculatum Spotted A. annulatum Ringed Fall Breeding Sept/Oct – April/May Overwintering Larvae Semi-permanent Ponds Spring Breeding Feb/March – June/July Seasonal Ponds
* This is based on the probability from analysis using BayesAssNM; Jehle et al DNA extraction PCR Multi-locus Genotyping Analysis Estimates of admixture rates among sampled populations* Genetics Study: Technical Approach
Results - Summary Spotted salamanders show no structure over 5-8 km 1)Suggests juveniles or adults have higher vagility 2)More successful producing juveniles in a wider range of pond habitats than ringed salamanders Peterman et al. 2014
Results - Summary Spotted salamanders show no structure over 5-8 km 1)Suggests juveniles or adults have higher vagility OR 2)More successful producing juveniles in a wider range of pond habitats than ringed salamanders Ringed salamanders show 2-3 genetically significant groups over distances of 5-6 km with unequal migration rates among groups and sub-groups Peterman et al. 2014
Results - Summary Spotted salamanders show no structure over 5-8 km 1)Suggests juveniles or adults have higher vagility OR 2)More successful producing juveniles in a wider range of pond habitats than ringed salamanders Ringed salamanders show 2-3 genetically significant groups over distances of 5-6 km with unequal migration rates among groups and sub-groups Avg. spotted salamander dispersal distance is 3.3 km Avg. ringed salamander dispersal distance is 2.7 km Peterman et al. 2014
A. annulatum Ringed
Genetic Conclusions Ringed salamanders exhibit source-sink dynamics Differential contribution of ponds Show directional movement of genes on the landscape Shows rates of movement and pond importance Difference in metapopulation dynamics may be a result of life history differences between species Ringed salamanders need more permanent ponds which means there is greater interpond distance and thus have less connected populations
Directed Management Modeling Combine genetic information with demographic field data to assess importance of ponds on landscape Strength of population abundance Corroborate with 3 years of field research Demographic data does not make sense without genetic Genetic data is the ultimate strength of connection Preview of some current work in our lab
Management Utility & Conclusions Identifies important source populations Contributing large amount of genes to metapopulation Increase connectivity of the landscape Enhances species persistence because it maintains source sink processes Identify which ponds are essential and which ponds can be mitigated Identifies sites for restoration and creation of ponds Identifies sites that are unimportant to source sink dynamics Aids in military training and military readiness
Funding Agencies: Field Assistance: -Thomas L. Anderson -Dana L. Drake -Jennifer L. Heemeyer -Brittany H. Ousterhout -Freya E. Rowland Lab Assistance: -Emily Brocato -Luke Pauley -Kim Romine -Brett Spatola -Elsa Stuart Questions?
Directed Management Modeling Current FLW Ponds Placement Requirements <17% slope Gravelly or silt-loam soils Forested habitat surrounding < 675m from existing roads Assumed salamander movement parameters Avg. dispersal distance of 300m (95% within 900m) 90% philopatric 100% larval survival Larval abundance is randomly selected Gamble et al. 2007; K. Lohraff, Pers. Comm.
A. maculatum Spotted A. annulatum Ringed
A. annulatum Ringed
Spotted Salamanders Ringed Salamanders