Satellites track turtle ‘lost years’
By Jonathan Amos
Science correspondent, BBC News
5 March 2014
New insights have been gained into the “lost years” of loggerhead turtles.
Tiny satellite tags have tracked months-old animals in the uncertain period when they leave US coastal waters and head out into the wider Atlantic Ocean.
The data suggests the loggerheads can spend quite some time in the Sargasso Sea, possibly living in amongst floating mats of sargassum seaweed.
The observations are reported in a journal of the Royal Society.
“This has been a fun study because the data suggest the turtles are doing something a little bit unexpected to what everyone had assumed over the past few decades, and it boils down to having the right technology to be able to follow the animals,” said lead author Dr Kate Mansfield from University of Central Florida, Orlando.
Scientists have long struggled to track the earliest years of Atlantic loggerheads (Caretta caretta).
After emerging from their nests on Florida’s beaches, the infant turtles, or neonates, make a dash for the water and head out on a great adventure.
Precisely where they go and what they do with their time before returning as large juveniles to the US seaboard has been something of a mystery.
Genetics studies, bycatch, strandings and opportunistic sightings offshore had given broad hints – that they travel in a huge circle within the currents associated with the North Atlantic subtropical gyre, reaching the Azores and Cape Verde before heading back to the Gulf of Mexico and Florida.
Tracking by satellite would give more definitive answers. However, attaching data tags to turtles that are just a few months old, and growing rapidly, is very tricky. But by using flexible mounts and preparation techniques usually found in a manicurist’s salon, Dr Mansfield’s team got the tags to stay on the animals’ shells for up to 220 days.
And it is with this new data that the scientists can see the young turtles dropping out of the gyre’s predominant currents into the middle of the Atlantic – into what is often referred to as the Sargasso Sea.
A panorama of the east face of hills showing strata from the John Day Formation in the Painted Hills Unit of the John Day Fossil Beds National Monument, in the U.S. state of Oregon. The strata, which vary in age from 18 million to 39 million years, were formed mainly from ashfalls from volcanoes to the west. The sediment layers vary in their chemical composition and color owing to the ash and other debris falling during varied climatic and volcanic conditions. (click here to see large format)
Photograph: Finetooth via: Wikipedia
U.S. government forecasters say odds are increasing that El Niño, an ocean-warming pattern that alters weather across the globe, will develop later this year.
Conditions in the eastern tropical Pacific have shifted enough that the National Oceanic and Atmospheric Administration on Thursday activated its alert system to issue an official El Niño watch.
The alert means that meteorologists now believe El Niño, a natural cycle that occurs every two to seven years, has a more than a 50% chance of forming by the summer or fall.
Its re-emergence could bring wetter weather to California and the southern U.S. next winter, temper the Atlantic hurricane season and push up global temperatures in 2015, experts say.
Oh Lord Jesus….
How to decide which extinct species should be resurrected
While not as cool as bringing dinosaurs back from extinction, some scientists are suggesting that certain butterflies and pigeons could return.
The Great Backyard Bird Count (GBBC)– one of the largest citizen science initiatives in the world – annually documents a wide variety of bird population trends. To my mind, one of the most interesting has been the dramatic spread of the non-native Eurasian collared dove across North America….
Last year’s bird count results showed the Eurasian collared dove had colonized much of the country. It has not (yet) been reported in New England, but it has reached as far north as Alaska….
What’s going on here? Should conservationists be concerned about this spread? Unlike some dove species, Eurasian collared doves aren’t migratory. However, they do readily expand into new suitable habitat. In fact, in their native Asia, Eurasian collared doves have been rapidly expanding their range as well – colonizing new countries every year.
The dove is one of those species that adapts well to humanity. The trees, power lines and bird feeders of suburbia provide perfect habitat. The Eurasian collared dove is almost always seen near homes and farms, not unbroken forest or prairie.
Research indicates it is not adversely affecting native mourning doves or other birds. It may simply be filling a new habitat niche created by suburban habitat. But it is still early in the spread. Could Eurasian collared doves become an invasive threat? That remains to be seen.