Where Sea Turtles Spend Their ‘Lost Years’
ERIK STOKSTAD | Science NOW
Now, researchers have published the first satellite tracking data from young sea turtles, charting a leisurely voyage under the sun. The youngsters idly float north along the Gulf Stream, then head toward the Azores. Along the way, they spend most of their time riding the waves, and the sun helps raise their body temperature. “The data from this handful of turtles could lead to some really important developments” in understanding turtle populations, says Nathan Putman, a turtle biologist at Oregon State University, Corvallis.
The early life of loggerheads and other sea turtles used to be called “the lost years,” because no one knew exactly where they went. But over decades, researchers pieced together the animals’ natural history from ship observations, the pattern of ocean currents, and other data. More recently, other scientists have studied isotopes from turtle tissue to analyze their diet and past locations and created computer simulations of their journey. The basic picture is this: Hatchlings head out to sea to avoid fish, sharks, and other predators. Once off the continental shelf, they eventually end up in a current, called the North Atlantic subtropical g. A few years later, they come back to their birthplaces on the East Coast of the United States.
The transmitters survived between 27 and 220 days, during which some turtles roamed as far as 4300 kilometers, the team reports today in the Proceedings of the Royal Society B. As expected, the turtles all headed north with the Gulf Stream, then most turned eastward around Cape Hatteras in North Carolina. The paths were consistent with what Putman’s computer models had predicted. The turtles weren’t single-mindedly heading toward the Azores, but looping around in small eddies and trying to avoid the coldest water. They also spent almost all of their time on the surface, and Mansfield suspects that this is to help stay warm. “It’s kind of a common sense thing,” Mansfield says. (They may also be waiting to develop the lung capacity for diving.)
Baby Black Ribbon Moray Eel
There are over 200 species of Moray eels. Worldwide, not one of them had been successfully bred until recently. At Zoo Vienna Schönbrunn in Austria, a Black Ribbon Moray laid a clutch of fertilized eggs. This fact alone is quite a sensation. But it gets better: some larvae even hatched!
"It is the first time that the hatching of Morays could be observed. Up to now, nobody knew what the larvae look like, what they eat and how they behave“, explains the zoo’s director Dagmar Schratter.
The breeding of Morays is completely new territory. The successful event in Schönbrunn Zoo supplies the first information - completely unknown up to now - about the development of their eggs and larvae.
Other than a certain week in August whose name we shall not speak here, 2013 was a great year for both shark science and the communication of that shark science. There were many important and fasci…
A great year for shark science. Congrats to my dive mentor Medel Silvosa on his contribution to #9!
Safety in Numbers? Not So for Corals
"The last 10 thousand years have been especially beneficial for corals. Acropora species, such as table coral, elkhorn coral and staghorn coral, were favored in competition due to their rapid growth. This advantageous rapid growth may have been attained in part by neglecting investment in few defenses against predation, hurricanes, or warm seawater. Acropora species have porous skeletons, extra thin tissue, and low concentrations of carbon and nitrogen in their tissues. The abundant corals have taken an easy road to living a rich and dominating life during the present interglacial period, but the payback comes when the climate becomes less hospitable.”
University of Hawaii (2013, November 15). Safety in numbers? Not so for corals. ScienceDaily.
Silly Acropora cut corners in Evolution class.
True(ish) facts about the Angler Fish
I can’t get enough of zefrank1
I’m going to ruin sea otters for you. Or at least Im going to tarnish their reputation as some of the most charming little beasties in the seas. For as cute as they are while intertwining paws at an aquarium, frolicking among the wafting fronds of California kelp forests, or…
Make your pumpkin wildlife-themed this year!
The advanced level has a Great White! But yet again, terrestrial themes outweigh the ocean.
WARNING: They will make you sign up for email updates before you can download the stencils.
Blue-ringed Octopus by Samantha Craven
Gato Island, Malapascua
The tiny, yet highly venomous Blue-ringed Octopus (Genus: Hapalochlaena). This individual was about 5cm in size.
In honour of World Octopus Day.
The Coral Song - by AJ Jenkins
Ladies and Gentlemen, I present to you the new soundtrack to my life. My work with the conservation project Green Fins is all about getting divers to help protect the reef, and reaching out to local communities to do the same. Whilst most divers and dive guides are fairly knowledgeable about the reef, I’ve met plenty of people, tourists and locals alike, who don’t know that coral is alive.
This is the soundtrack for all my future presentations. And the song that will be in my head for the rest of the week. And I don’t even mind.
Go ahead. Enjoy. Sing. Share.
Hear hear! Whales record major life events in their earwax.
Who needs a diary when you’ve got whale earwax? Hormone peaks, ocean pollutants, stress levels – it’s all there.
The plugs, which can weigh 250 grams and be 25 centimetres long, reflect annual migration patterns. During a blue whale’s six-month feeding season, earwax is light-coloured, filled with fat from its rich diet. As it fasts during migration, a darker layer forms. These layers allow scientists to age whales when they’re found dead.
Now, for the first time researchers have used the earwax to study a whale’s exposure to ocean contaminants from birth to death. “This has opened the floodgates for doing some great analysis,” says Sascha Usenko of Baylor University, Waco, Texas. “Now we can look at the impact of ocean contaminants on these organisms historically, which has always been very hard to address.”
Usenko and Stephen Trumble, also at Baylor University, shaved away at a plug from a 12-year-old male blue whale that was killed in a 2007 boating accident off the coast of California. The layers contained varying concentrations of DDT and flame-retardants. Exposure was highest during its first year, probably while the whale was nursing.
The plug also contained traces of hormones, which are broken down by the body and don’t leave records elsewhere. Testosterone levels peaked at 10 years, marking the beginning of sexual maturity, which can be difficult to determine but is important for conservation efforts. And levels of the stress hormone cortisol increased over the whale’s life, possibly because finding food, migrating and mating all got harder.
Usenko says the earwax method means we can look at how exposure to chemicals in the environment alters a whale’s stress levels, and how exposure today is different from exposure say, 50 years ago.
Photo 1: Giant earplug (Image: Tonya B. Lewis/Baylor University)
Photo 2:The extracted whale earplug (B); a cross-section of the earplug (C); and a cross-section of the earplug magnified 20x to show the different waxy layers. Source: Smithsonian Blog.
Journal reference: PNAS, DOI: 10.1073/pnas.1311418110