Basking Characteristics of Blanding’s Turtles in Natural and Constructed in Southeastern New York

Tanessa Hartwig, Erik Kiviat, and Gretchen Stevens

Hudsonia Ltd., Annandale, NY

Presentation  2008 Tanessa Hartwig Emys blandingii : NYS Threatened

Threats in Dutchess County, NY: • roads, construction, farm equipment • habitat degradation and loss • fragmentation and sprawl • subsidized predators • collecting BlandingBlanding ’’ss TurtleTurtle HabitatsHabitats inin DutchessDutchess CountyCounty

Core Habitat: Deep-flooding shrub with organic , near gravelly glacial outwash Associated Wetland : : Vernal (woodland) pools, flooded swamps, Spring-fed natural or artificial , or beaver ponds, other flooded wetlands deep pools in wetlands

Estivation Habitat: Wetland , upland woods under logs or in shrub thickets, stream pools ConstructedConstructed Habitats,Habitats, 19961996 --19971997 Moving Wetland Sods

Loading sods on truck Spatula for cutting sods Sods and organic soil Placing sods in basin

Inspiration for sod technique: Munro Ecological Services MethodsMethods • Turtle-centered plots May to September, 2000-2002, in constructed and natural wetlands • Turtles trapped and radios attached; turtles radiotracked to exact location • Vegetation, temperature, and water depth recorded in a 3 x 3 m plot centered on the turtle • Vegetation surveyed in permanent random 3 x 3 m plots each September GeneralGeneral AssociationsAssociations

• Shallow water depths (mean = 30 cm) • Abundant vegetation (total cover mean = 87%) • Buttonbush (Cephalanthus occidentalis ) (mean = 30%) • “Edges” between emergent vegetation and moats Natural/ConstructedNatural/Constructed

• Turtles positively Total Cover 2002 Means R Nat = 107% associated with high total 60 R Con = 117% cover in natural wetlands, 40 20 Total Cover 2002 but negatively associated 0 with total cover in -20 T Nat = 90% constructed wetlands -40 Random Turtle Centered T Con = 54%

Confidence intervals on the differences in means between natural and constructed wetlands. WaterWater TemperaturesTemperatures Turtles found in warmer water in constructed wetlands than in natural wetlands (t-value = 3.76; P ☯ 0.001).

32 30 28 26 24

22 Constructedwetlands Naturalwetlands 20 18 16 14 12 10 Water Temperature, Degrees Celsius 8 6 80 100 120 140 160 180 200 220 240 260 280 300 320 Julian Date 2002 180 160 BaskingBasking PatternsPatterns 140

120 • Logs in the early morning; 100 floating materials (, 80 duckweeds, etc.) by late 60 morning 40 Percent cover coarse woody debris woody Percentcoarse cover 20 • Conserving energy by 0 7:12 9:36 12:00 14:24 16:48 19:12 21:36 basking and foraging 180 simultaneously

160

140

120 Constructed Constructed wetlands wetlandsNatural 100

80

60 Percentneuston cover 40

20

0 7:12 9:36 12:00 14:24 16:48 19:12 21:36 Time Natural wetlands Constructed wetlands Julian date 2002 date Julian Provides: food , warmer food Provides: resources, predators. cover from microclimate, Submerged Vegetation Submerged Submerged Vegetation Submerged 80 100 120 140 160 180 200 220 240 260 280 300 320 0

80 60 40 20

160 140 120 100 Percent cover submerged vegetation submerged cover Percent Algae Cover 2002 Means 20 R Nat = 0% 15 R Con = 0% 10 Algae Cover 2002 • Turtles positively 5 T Nat = 13% associated with 0 T Con = 4% filamentous algae in the Random Turtle-centered natural wetlands and with water celery in the Water Celery Cover 2002 constructed wetlands Means

0 1 2 R Nat = 0% -5 R Con = 0% -10 Water Celery -15 Cover 2002

-20 T Nat = 0% T Con = 12% -25 Females used the constructed wetlands more often than males. (2001 χ2 = 15.13, df = 1, P ≤ 0.001; 2002 χ2 = 88.14, df = 1, P ≤ 0.001).

Yr Wetland type No. of F No. of M F:M observations observations 2000 Both 467 100 4.7:1 2000 Natural 297 68 4.4:1 2000 Constructed 170 32 5.3:1 2001 Both 633 330 1.9:1 2001 Natural 479 285 1.7:1 2001 Constructed 154 45 3.4:1 2002 Both 727 524 1.4:1 2002 Natural 490 472 1.0:1 2002 Constructed 237 52 4.6:1 Total turtle observations natural (2000-2002) 2091 Total turtle observations constructed (2000- 690 2002)

ConclusionsConclusions • Constructed wetlands provided basking and foraging habitat in the spring and early summer, and staging or rehydrating areas for nesting females. • Basking habitat should include shallow water areas with submerged and floating vegetation, interspersed with emergent vegetation and basking substrates such as logs. • Some basking habitat should be near nesting areas. Tanessa Hartwig Assistant Director, Conservation of Habitats and Species Hudsonia Ltd. P.O. Box 5000 Annandale, NY 12504 (845) 758-7274 [email protected] www.hudsonia.org

Acknowledgments Hudsonia Ltd. Field workers : Heidi Bock, Dan Goodfriend, Krista Munger

Funders: AmeriCorps, Arlington Central School District, ENSR, Geoffrey C. Hughes Foundation, Guinness Water of Life, New York State Office of Parks, Recreation & Historic Preservation, Society for Ecological Restoration, U.S. Environmental Protection Agency

Collaborators: AmeriCorps; Arlington Central School District, consultants and contractors; Creative Habitat; New York State Department of Environmental Conservation; New York State Office of Parks, Recreation, & Historic Preservation

Photo credits: Tanessa Hartwig, Erik Kiviat, Andy Reinmann, Gretchen Stevens, Carolyn Summers