Study

Hatching Success and Predation of Bog Turtle (Glyptemys muhlenbergii) Eggs in New Jersey and Pennsylvania

  • Published source details Zappalorti R.T., Tutterow A.M., Pittman S.E. & Lovich J.E. (2017) Hatching Success and Predation of Bog Turtle (Glyptemys muhlenbergii) Eggs in New Jersey and Pennsylvania. Chelonian Conservation and Biology, 16, 194-202.

Actions

This study is summarised as evidence for the following.

Action Category

Protect nests and nesting sites from predation using artificial nest covers: Tortoises, terrapins, side-necked & softshell turtles

Action Link
Reptile Conservation

Relocate nests/eggs for artificial incubation: Tortoises, terrapins, side-necked & softshell turtles

Action Link
Reptile Conservation
  1. Protect nests and nesting sites from predation using artificial nest covers: Tortoises, terrapins, side-necked & softshell turtles

    A replicated, controlled study in 1974–2012 in 11 wetland sites in New Jersey and Pennsylvania, USA (Zappalorti et al. 2017) found that caged bog turtle Glyptemys muhlenbergii nests had lower predation rates compared to uncaged nests, but overall hatching success was not higher. Fewer eggs were predated in caged nests (6 of 97 eggs, 6%) compared to uncaged nests (82 of 161 eggs, 51%), but overall hatching success was not higher for caged nests (caged: 42 of 97 eggs, 43%; un-caged: 53 of 161 eggs, 33%). Cages of 1 cm wire mesh were installed over nests (61 cm high, 38 cm wide) and buried 8–15 cm into the ground. In June 1974–2012, twenty-seven nests in five wetlands were covered with cages, and 55 nests in 11 wetlands were left uncaged. Eggs were monitored for at least 8–9 weeks to record predation and hatching success.

    (Summarised by: William Morgan)

  2. Relocate nests/eggs for artificial incubation: Tortoises, terrapins, side-necked & softshell turtles

    A replicated, controlled study in 1974–2012 in a laboratory and 11 wetland sites in New Jersey and Pennsylvania, USA (Zappalorti et al. 2017) found that bog turtle Glyptemys muhlenbergii eggs incubated in a laboratory had higher hatching success than eggs left in wild nests. Hatching success was higher for eggs in the laboratory (74 of 91, 81% [numbers taken from table]) than for eggs in wild nests (caged nests: 42 of 97, 43%; uncaged nests: 53 of 161, 33%). Average hatching date was similar in the laboratory and field (30–31st August). Eggs were transferred from nests to a laboratory and incubated in plastic containers with humus from the wetland. Incubation temperatures ranged from 26–32°C during the day, and 17–24°C at night. In 1974–1993, a total of 91 eggs from five wetlands were transferred to the laboratory. In 1974–2012, a total of 258 eggs from 11 wetlands were monitored in 27 caged and 55 uncaged nests. Cages were 1 cm wire mesh and buried 8–15 cm into the ground. All eggs were monitored for at least 8–9 weeks to assess hatching success, and hatchlings from the laboratory were released at the original nest site within 5–10 days.

    (Summarised by: William Morgan)

Output references
What Works 2021 cover

What Works in Conservation

What Works in Conservation provides expert assessments of the effectiveness of actions, based on summarised evidence, in synopses. Subjects covered so far include amphibians, birds, mammals, forests, peatland and control of freshwater invasive species. More are in progress.

More about What Works in Conservation

Download free PDF or purchase
The Conservation Evidence Journal

The Conservation Evidence Journal

An online, free to publish in, open-access journal publishing results from research and projects that test the effectiveness of conservation actions.

Read the latest volume: Volume 21

Go to the CE Journal

Discover more on our blog

Our blog contains the latest news and updates from the Conservation Evidence team, the Conservation Evidence Journal, and our global partners in evidence-based conservation.


Who uses Conservation Evidence?

Meet some of the Evidence Champions

Endangered Landscape ProgrammeRed List Champion - Arc Kent Wildlife Trust The Rufford Foundation Mauritian Wildlife Supporting Conservation Leaders
Sustainability Dashboard National Biodiversity Network Frog Life The international journey of Conservation - Oryx Cool Farm Alliance UNEP AWFA Bat Conservation InternationalPeople trust for endangered species Vincet Wildlife Trust