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Titel: Turtles: In response (David Steen, Auburn, Ala)
Bericht door: schildpaddennetcrew op 17 Oktober 2008, 12:22:33
THE OBSERVER (Moultrie, Georgia) 02 July 08 Letter: Turtles: In response (David Steen, Auburn, Ala)

Dear editor: The article: “County trapper says turtle data not credible” published on June 23rd in The Observer needs clarification.
The reader is given the impression that The Center for Biological Diversity, Satilla Riverkeeper, Altamaha Riverkeeper and The Center for Food Safety is petitioning the state of Georgia to place restrictions on collection of, among other species, snapping turtles. Two alligator snapping turtles, Macrochelys temminckii, are pictured along with the article. It is already against Georgia state law to collect this animal; this law was enacted because of well documented precipitous declines associated with the past commercial harvest of this species. Is it possible that the figures stated within the article actually refer to the common snapping turtle, Cheldyra serpentina?
Raccoon removal is cited as a potential method of helping turtle populations. However, removing a natural predator is not an effective method of conservation. Turtles and raccoons have lived in the same habitat for thousands of years, recent declines of turtle populations cannot be attributed to these natural predators. If turtle populations have been observed declining over the last few decades, it is much more likely that it is because of our actions.
It may be possible that the number of ponds in southwest Georgia has increased, although I?m not sure where these data were obtained, and it is true that these wetlands may represent appropriate habitat for some turtles, such as sliders, Trachemys scripta, and common snapping turtles, but a turtle is not a turtle. The most vulnerable species in our region include map turtles, Graptemys sp. and the alligator snapping turtle.
The primary habitat for these species is riverine systems such as creeks and rivers, they seldom to never occur in ponds.
It should be stressed that the four groups mentioned above are not petitioning to permanently stop turtle collection, they are stating that unregulated commercial collection should stop until biologically informed management guidelines can be generated. Commercial, unregulated collection is never a good idea; it has been implicated in the decline of species throughout North America.
We stopped this practice in time to save white-tailed deer and wild turkey from our eastern forests and the American alligator and the alligator snapping turtle from wetlands of the Southeast. The only reason that these species did not go extinct, as the passenger pigeon did, is we recognized the problem early enough to enact sustainable harvest guidelines. That is exactly what we need to do for our turtles.
Turtles are a long-lived species that don?t reach sexual maturity often until they are over ten years old. Therefore, it is not possible to detect trends in populations in only a few short years. For example, if a turtle species reaches sexual maturity in ten years, then every single adult turtle from a population could be removed and there would still be individuals becoming adults for ten years (as the young turtles hatched in previous years mature). It is only after all these turtles have been recruited into the population would we realize that very few young are being produced each year.
Of course, the current harvest of these turtles does not remove every single adult turtle, so the trends will be more subtle, although they are likely occurring. We must look at these populations over several decades to determine trends. Numerous studies over this time span confirm that for some species of turtles, the numbers we see today are only a shadow of what they were in the 1960?s and 1970?s. It is time to stop unregulated collection before these trends continue beyond the point where we can reverse them.
David Steen, Auburn, Ala.
http://www.moultrieobserver.com/opinion/local_story_184225137.html