SUPERHERO TORTOISES STEP IN TO SAVE ISLAND
The rewilding world is agog with news that giant Aldabra tortoises are performing miraculous acts of ecological restoration, bringing a near-extinct tree species back to life. Introduced from the Seychelles Islands to the Ile aux Aigrettes (near Mauritius in the Indian Ocean), the bulky behemoths stepped into the role once filled by a extinct tortoise species, aiding the ebonies by dispersing their seeds and kindly passing them through their guts for added germinatory goodness.
Christine Griffiths, an author of the Current Biology study, “Resurrecting Extinct Interactions with Extant Substitutes,” that documented the regeneration of ebony seedlings, argues that, “Reversible rewilding experiments such as ours are necessary to investigate whether extinct interactions can be restored.” What’s next? Mexican gray wolves?
Treehugger offers a great write-up, while Science Daily calls it ” the first empirical evidence that rewilding can work.”
Photo: timparkinson / cc
CLIMATE CHANGE THREATENS TALLEST TREES ON EARTH
An important new study has demonstrated that the coastal fog providing today’s Endangered All-Star, the Coast Redwoods, with crucial cool temperatures and moisture has declined over the past century by around three hours per day, potentially endangering the entire coastal ecosystem surrounding and supporting these great trees. There are excellent summaries of the study, published in the Proceedings of the National Academy of Sciences, on Mongabay and on Science Daily, which quoted coauthor Todd E. Dawson, UC Berkeley professor of integrative biology in the Department of Environmental Science, Policy and Management: “Fog prevents water loss from redwoods in summer, and is really important for both the tree and the forest. If the fog is gone, we might not have the redwood forests we do now.”
Utilizing data from 114 weather stations along the Pacific coast, the study shows that the 33% reduction in fog affects not only the region of northern California and southern Oregon where the redwoods grow but the entire coastline, from Seattle to San Diego. This may presage great changes in coastal ecosystems, as Dawson suggested to Science Daily: “As fog decreases, the mature redwoods along the coast are not likely to die outright, but there may be less recruitment of new trees; they will look elsewhere for water, high humidity and cooler temperatures. What does that mean for the current redwood range and that of the plants and animals with them?”
Those interested in learning more about the redwood ecosystem need look no further than Richard Preston’s wonderful The Wild Trees: A Story of Passion and Daring which introduces the daring exploits of naturalists and botanists who explore these giants and the extraordinary communities of organisms—mosses, lichens, salamanders, ferns— that flourish in their canopies. Preston opens his book with a line from Rachel Carson: “Those who dwell among the beauties and mysteries of the earth are never alone or weary of life.”
If you can, join or donate to the organization that supported the redwood research described above: Save the Redwoods League.
Photo: Scott Catron, for Wikimedia Commons
