Nathan W. Byer1,2, Craig Nein3, Scott A. Smith4, and ...

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to Predict Recruitment Rates for a Threatened Turtle Species ... Turtles are one of the most threatened taxonomic ... two Bog Turtle populations in Maryland.
The Significance of “Good Years”: Using Demographic Modeling to Predict Recruitment Rates for a Threatened Turtle Species Nathan W.

1,2 Byer ,

Craig

3 Nein ,

Scott A.

4 Smith ,

and Richard A.

1 Seigel

1: Department of Biological Sciences, Towson University, Towson, MD ; 2: Present Address: Department of Forestry and Wildlife Ecology, University of Wisconsin – Madison, Madison, WI (contact: [email protected]); 3:Johnson, Mirmiran and Thompson, Inc., Sparks, MD; 4: MD DNR – Wildlife and Heritage Service, Wye Mills Field Office, Wye Mills, MD

Introduction • Turtles are one of the most threatened taxonomic groups – as of 2012, 228 out of 322 turtles are listed on the IUCN Red List • Field studies suggest that turtles experience high rates of egg and nest depredation – often close to 100% • Most studies are of short duration - may miss years where nest failure is less severe • Failing to take into account undetected variation in recruitment rates may lead to inaccurate population assessments

The Bog Turtle

Results and Discussion

• Habitat specialist – requires wet meadows and bogs • Low reproductive output (1-5 eggs) • Small population sizes

Figure 1: Photograph of a (often