Climate Change and the Future of our Turtles
Climate Change is going to affect how and where our Earth’s plants and animals are going to live in the future. Some species will thrive, while others will sadly perish, but what about our turtle friends? What will happen to them as the climate changes? A large report has just been released by PLoS One that integrates data from more than 300 published studies on how turtles have responded in their physiology, genetics, and fossils to climate-changes over the last 320 millennia
The study looked at the Earth’s climate cycles through three glacial-interglacial cycles. Interglacial means a period of time when our earth was warm, which separated the cold periods during an ice age (Figure 1). Presently, we are in a warm period called the Holocene period (Figure 2), but human activities, like extensive burning of fossil fuels, have caused temperatures to rise at unprecedented rates and could be the cause of sudden climate changes.
This report looked at significant variation in temperatures during past climatic cycles and its effect on 59 species of North American turtles. It was found that turtle populations were able to slowly shift to different habitat locations on an average of 72km/degree of warming or cooling. Some turtle species were able to find a wide variety of habitat in a suitable climate, while other species, many of which are endangered today, were left with no place to go.
The report found that species in Central and Eastern US, inhabiting temperate forests, grasslands, deserts, and lake systems were more affected by climate change than species occurring in the Western US, along the Pacific Coast and mountain highlands. Locating future problem areas is important to estimate future extinction risks, and areas to focus conservation efforts.
The big issue is that the successful move by turtles to new habitat takes a long period of time, and today’s climate is changing at a much more rapid rate compared to other historic cycles. This means turtles will have a hard time adapting naturally to tolerate climate changes, and new real estate is running out.
According to the International Union for Conservation of Nature (IUCN), more than half of the world’s turtle and tortoise population, approximately 330 species, are threatened with extinction due to illegal trade, road mortality and habitat loss. This is a higher extinction risk than the majority of the earth’s vertebrates, and paralleled only by the extinction of primates.
So what can we do? Get involved in your community! Become an environmental steward and support the protection, restoration and creation of wetlands and habitat corridors. Organize a wetland garbage cleanup. Help turtles that are seen crossing the road and install turtle crossing signs in areas of high wildlife road mortality. If you have a large property, think about building a turtle pond or turtle nesting beach. Participate in population monitoring programs like Ontario Turtle Tally and FrogWatch Ontario.
If you need help with any of these ideas contact Adopt-A-Pond for more resources and advice.
Dennis Rödder, Michelle Lawing, Morris Flecks, Faraham Ahmadzadeh, Johannes Dambach, Jan O. Engler, Jan Christian Habel, Timo Hartmann, David Hörnes, Flora Ihlow, Kathrin Schidelko, Darius Stiels, David Polly. Evaluating the Significance of Paleophylogeographic Species Distribution Models in Reconstructing Quaternary Range-Shifts of Nearctic Chelonians. PLoS One, October 2013