Follow eleven turtles as they sprint from Costa Rica to near the Galapagos. Each of them has a corporate sponsor, and at 20 miles an hour, they will get there in a couple of weeks! I think Billie’s going to win, but the leatherback turtle is in bad shape, endangered due to poaching, adult mortality and habitat loss. They may be gone very soon.
Here’s the flickr page for the race, some beautiful pictures already.
Across a population studied by scientists, more turtles preferred to use their right rear flipper rather than their left when laying eggs.The result, published in the journal Behavioural Brain Research, is the first time a species of turtle has found to prefer one limb over another.The discovery adds to growing evidence that even lower vertebrates prefer to use one side of the body more often.Such preference is known by scientists as a “lateralised functional behaviour”, and it usually indicates that an animal's brain function is also lateralised, with one side of the brain dominating control of certain tasks.
via BBC – Earth News – Turtles are ‘right-flippered’.
Ha, just when you thought Tuesdays with Turtles was gone, it is Tuesday (here in Canada) and a sea turtle post. Turns out, leatherbacks, the biggest of ths sea turtles and critically endangered tend to be right flippered while on land and laying eggs. A slight predilection to right sidedness runs all the way down to reptiles. It is 54%-46%, which does not seem like much, but the report indicates that among humans, it is the same once you control for a cultural right hand bias!
Anyway, got to love those sexy beasts, even if they’re right flippered, right Ned?
I mentioned recently that elevated temperatures from climate could skew sea turtle sex ratios towards females. The featured news article highlights research which speculates that storm surges caused by increased hurricane (they call them cyclones in Austraila and India) intensity from climate change might lead to the flooding of green turtle nests in Florida, hastening their extinction. Why only the greens? Because they nest later than the other turtles and tend to be around during the height of the Atlantic hurricane season.
We know from previous research that loggerhead turtles have been nesting earlier because of elevated temperatures. Will the greens catch up. More pertinently, will there be enough survival of the early nesters of this generation to keep a viable population going while the whole population adapts? As with all climate change suspense thrillers, only time will tell… Depressing, at any rate.
News in Science – Cyclones may blast turtles to extinction – 15/05/2007
More severe tropical cyclones expected as a result of climate change may lead to the extinction of the green sea turtle in some areas within 100 years, researchers say.
The cyclones are expected to threaten how well the turtles nest and hatch eggs, placing pressure on already endangered populations, some of which are also threatened by fish trawling.
Researchers including PhD candidate David Pike, from the School of Biological Sciences at the University of Sydney, report their findings online in the journal Oecologia.
The researchers studied more than 40,000 sea turtles nests on an uninhabited, 38 kilometre stretch of beach along the Atlantic coast of Florida from 1995 to the end of 2005.
Each night during this period researchers surveyed the beach for turtles emerging to lay eggs, or for tracks of turtles that had already deposited eggs.
The stretch of beach is home to the loggerhead, green, and leatherback sea turtles, which start nesting at the beginning in April and end in late September.
This nesting season largely coincides with region’s tropical storm season, which runs from June to November.
Leatherback turtles (Dermochelys coriacea) and, to a lesser degree, loggerhead turtles (Caretta caretta) get around this by nesting and hatching earlier.
Only nests laid late in the season are inundated with seawater during storm surges.
But green turtles (Chelonia mydas) nest last.
Their entire nesting season occurs during Florida’s tropical cyclone season, which means their nests and developing eggs are extremely vulnerable to being washed away and killed.
Researchers are concerned that increases in the severity of tropical cyclones in the future may cause green turtle nesting success to worsen.
A little old, but turns out that the WWF is establishing a hatchery for Olive Ridley sea turtles in Orissa.
WWF-India comes with artificial hatchery for Olive Ridley eggs – Newindpress.com
Large-scale destruction of Olive Ridley eggs at nesting sites in the State’s coast has prompted WWF-India to come with an artificial hatchery. It would also double up as a hatching protection centre. The artificial hatchery has been established near mouth of Rushikulya river where WWF-India staff have stored a large number of Olive Ridley eggs along with the arrangements for safe hatching. Last month alone, 116 nests were safeguarded and around 13,000 Olive Ridley eggs were stored in the artificial hatchery. Till end of the week, more than 2,000 eggs have hatched, chairman of WWF-India, Orissa State Committee Saroj Kumar Patnaik said.
Hatcheries become necessary when the natural habitat can no longer be protected. The biggest advantage of a hatchery is the fact that once the eggs are relocated, they are now safe from poaching/predation. But, there are some disadvantages including the resources needed, the possible overcrowding effects if the hatcheries are not well designed, etc. Luckily, there are good resources available for building and managing a good hatchery. With the WWF’s funding and experience, I am sure it will be a very well managed hatchery.
In case I forgot to mention, the Olive Ridley arribada started during the 2nd week of February, so about 50 days later, here they are, the “millions” of hatchlings.
The Hindu News Update Service
Olive Ridley hatchlings emerge in Gahirmatha
Kendrapara (Orissa), April 10. (PTI): Millions of tiny olive ridley sea turtle hatchlings are now emerging out of nests at the Gahirmatha beach in Orissa’s Kendrapara district, wildlife officials said on Monday.
The eggs laid by thousands of adult females in the Nasi-2 and Babubali islands in the Gahirmatha marine sanctuary have began to hatch over the last two days, they said.
Wildlife officials stationed at the nesting grounds were witness to the phenomenon, but tourists and researchers were not allowed into the unmanned territory close to the Wheeler’s island where a defence test range is located.
India’s intermediate range nuclear-capable missile Agni III is likely to be test fired from there some time this week, defence sources said.
You know what, the fact that this area is under close military supervision because of India’s grandiose missile dreams may not be sucha bad thing (sacrilege!!!). The area is under so much development pressure that even military operations are better than the alternative.
For more about the Gahirmatha area, visit the official website. At this point in time, the Arribada is very tourist unfriendly, and there are few, if any volunteering opportunities. I will keep any eye open for changes
Technorati Tags: olive ridley, sea turtles
Drift Gillnet Management
The Council adopted a recommendation to NMFS to authorize an exempted fishing permit (EFP) that would allow drift gillnet fishing in the current August 15-November 15 closed area. The EFP fishery would be governed by several requirements for all vessels, including, to carry an observer; to limit total fishing effort in the EFP fishery to 300 sets; to immediately cease the EFP fishery if, and when, two leatherback sea turtles were encountered by the fishing gear; and to immediately cease the EFP fishery if one mortality or serious injury occurred to any of the following marine mammals: short-finned pilot whale, sperm whale, fin whale, gray whale, humpback whale, or minke whale.
And, with that, starts the rather egregious practice of drift gillnet fishing. The restrictions seem fairly tight, an observer on every boat, and end to the fishery after two incidences of capture. There is definitely more than meets the eye here, I don’t know what. Drift gillnet fishing is well documented to cause turtle catch, this from the 1998 Fishery Bulletin for 1990-1995
In the drift gillnet fishery, seven out of 387 mammals observed entangled were released alive. In the set gillnet fishery, five out of 1,263 mammals observed entangled were released alive. Estimates of incidental kill are presented along with estimates of entanglement for species that were observed to be released alive. For the period under consideration, the estimated mortality for the drift gillnet fishery was over 450 marine mammals each year. A total of 20 turtles and 3 seabirds were observed entangled during the entire period. The most frequently entangled species in this fishery were common dolphins, Delphinus spp., and northern elephant seals, Mirounga angustirostris. Estimated cetacean mortality in the driftnet fishery decreased from 650 in 1991 to 417 in 1995; pinniped mortality decreased from 173 in 1991 to 116 in 1995. Estimated cetacean mortality in the set gillnet fishery ranged from a high of 38 in 1991 to a low 14 in 1993; pinniped mortality rose to a high of 4,777 in 1992 and then decreased to 1,016 in 1995. We postulate that there has been a decline in the number of pinnipeds and cetaceans in the setnet fishery owing to area closure. No similar proposal can be made for the driftnet fishery. The most frequently entangled mammals in the setnet fishery were California sea lions, Zalophus californianus, and harbor seals, Phoca vitulina. Six turtles and 1,018 seabirds were estimated entangled in this fishery during the NMFS Observer Program from July 1990 to December 1995.
So what’s the deal, this thing caught 20 turtles in 5 years, so it is going to catch turtles, no doubt about it. Anyone who does not get what the death of one adult sea turtle means read this. Sea turtles are wonderfully fragile animals given their size, they take long to mature sexually, they do not breed all that much and less than 1% of turtle hatchlings survive to adulthood. Leatherbacks are highly endangered.
I have a feeling that this is the first part of a one-two punch intended to reinstate the famed turtle killer long line swordfish nets on the pacific coast. The “proof” that these nets do not catch turtles will be used to lobby for longline swordfishing in, oh say three months?
The Students’ Sea Turtle Conservation Network was featured in the Hindu today.
Sea turtle lovers are concerned at the disturbance caused to turtle nesting habitats along the Tamil Nadu coastline, where casuarinas have been raised by the State Forest Department.The sea turtle’s egg-laying season began a month ago. Volunteers of the Chennai-based Students’ Sea Turtle Conservation Network (SSTCN) had written to the World Bank stating that the Forest Department should reverse the damage done.The SSTCN also wanted the Bank to provide funds for taking up transplantation work.Akila Balu, co-ordinator, SSTCN, said after the tsunami, the World Bank funded an Emergency Tsunami Reconstruction Project (ETRP) in Tamil Nadu.Under this programme, the State Forest Department had taken up the work of raising casuarina plantations to act as a bio-shield on the coastline. The casuarina saplings were planted right up to the high-tide line. In the process, it eliminated large stretches of sea turtle nesting habitat.Department’s defenceA senior Forest Department official said casuarinas had not been raised all along the State coastline.Adequate space had been provided between each sapling through which the turtles could enter the sand and lay eggs.The ETRP is a conservation-oriented programme, and so far the department has not received any complaints that the casuarina plantation had affected egg-laying of the Olive Ridleys, the official said.“In most of the areas, the saplings are not touching the high-tide line. If we plant closer to the line, the saplings will not survive. On the whole, the plantation will surely not affect the egg-laying turtles,” the official added.
The Hindu : Tamil Nadu / Chennai News : “Casuarina plantations affecting turtle nesting habitats”
To find out more, visit the SSTCN website.
cross-posted at the Students’ Sea Turtle Conservation Network
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Tags: SSTCN, Olive Ridley, Sea Turtles, Chennai