![]() Others, such as the beautiful Burmese star tortoise ( Geochelone platynota) and the less-charismatic western swamp turtle ( Pseudemydura umbrina), Australia's rarest reptile, are among the 25 most endangered turtles in the world (Turtle Conservation Coalition 2018), requiring captive breeding and intensive management to keep them from extinction. For the past 8 or more years, she has not produced fertile eggs, despite international efforts to propagate the species, including the use of artificial insemination. One such species, the Yangtze giant softshell turtle ( Rafetus swinhoei) is reduced to perhaps four surviving individuals, and only one is known to be a female. For example, some turtle species are no longer found in their native habitat and exist only in captivity. Specific examples of the recent plight of turtles are exemplified by several species worldwide. The vulnerability of turtles, in part, is due to a global focus by conservation programs to prioritize and target areas that protect birds and mammals but do not adequately consider turtle diversity (Roll et al. Turtles are arguably the most threatened of the major groups of vertebrates in general and are proportionately more so than birds, mammals, fishes or even the much-besieged and heavily publicized amphibians (Hoffmann et al. As of 2017, 356 turtle species were recognized worldwide (Turtle Taxonomy Working Group 2017), of which approximately 61% are threatened or have become extinct in modern times. Scientists identify 14 living families and many extinct ones. Turtles are struggling to persist in the modern world, and that fact is generally unrecognized or even ignored. Their enduring success is due in no small part to a conservative morphology and time-tested adaptations that allowed them to outlive even the dinosaurs, which disappea red over 65 million years ago, when turtles were already an old lineage. Turtles are an ancient group going back over 200 million years (Ernst and Lovich 2009). ![]() ![]() As previous paleontologists have noted, if they were known only from fossils, they would be cause for wonder. That such remarkable and familiar animals are considered by many to be ordinary is unfortunate, because no vertebrate animal that has ever lived has possessed the unique architecture of turtles, with their limb girdles encased inside a bony shell. The word turtle applies to all animals with a bony shell and a backbone, whether they are locally referred to as turtles, tortoises, or terrapins (Ernst and Lovich 2009). This prosaic status makes them easy to take for granted or even overlook as important ecosystem components worthy of protection. Turtles are so universally recognized by virtually all cultures and age groups that it is easy to see them as merely commonplace animals, even though many are far from common. The collapse of turtle populations on a global scale has greatly diminished their ecological roles. As a result of their numerical dominance, turtles have played important roles as significant bioturbators of soils, infaunal miners of sea floors, dispersers and germination enhancers of seeds, nutrient cyclers, and consumers. Two notable characteristics of pre-Anthropocene turtles were their massive population sizes and correspondingly high biomasses, the latter among the highest values (over 855 kilograms per hectare) ever reported for animals. ![]() Reasons for the dire situation of turtles worldwide include the familiar list of impacts to other species including habitat destruction, unsustainable overexploitation for pets and food, and climate change (many turtles have environmental sex determination). Turtles are among the most threatened of the major groups of vertebrates, in general, more so than birds, mammals, fishes or even the much besieged amphibians. Of the 356 species of turtles worldwide, approximately 61% are threatened or already extinct.
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