Tag Archives: conservation

Sea turtles are Gulf travelers, scientists say

23 Dec
 Loggerhead “exchanges” between study sites. Tracks of satellite-tagged adult female loggerheads (Caretta caretta) 119941 and 119946 during the inter-nesting period in 2012 (A); tracks of satellite-tagged adult female loggerheads 108172 (2011) and 119940 (2012) during the inter-nesting period (B). doi:10.1371/journal.pone.0066921.g002

Loggerhead “exchanges” between study sites.
Tracks of satellite-tagged adult female loggerheads (Caretta caretta) 119941 and 119946 during the inter-nesting period in 2012 (A); tracks of satellite-tagged adult female loggerheads 108172 (2011) and 119940 (2012) during the inter-nesting period (B).
doi:10.1371/journal.pone.0066921.g002

Gulf Loggerheads were always thought to be homebodies.

After the females nested, they would make a home at their local beach. They would never travel too far from familiarity.

But, these  threatened female loggerheads are more curious than scientists once thought.

A new study suggests that the turtles nest in different places–laying eggs on the coast of Louisiana one week and traveling hundreds of miles to make another home in Florida weeks later.

The authors of the U.S. Geological Survey study say that the travel routes–which may be littered with leftover oil and increased predators–pose a greater risk to the sea turtle population. The conservation efforts may need to be modified to reflect the findings.

“The satellite data and our observations on the ground tell the same story: loggerheads in this subpopulation nest at multiple beaches, sometimes hundreds of miles apart,” lead author Kristen Hart, a USGS research ecologist, said.

Co-author and USGS biologist Meg Lamont said that simply protecting beaches that are known to be highly populated with sea turtle nests may not be enough.

“These data show it is not sufficient to just protect habitat around high density nesting beaches – such as the St. Joseph Peninsula – because many turtles that nest on the Peninsula use the entire region from the eastern Florida Panhandle to Louisiana,” said Lamont.

Hart said she and her team are continuing to map out the travel routes by tagging the turtles.

“We are working towards defining areas where sea turtles concentrate their activities at sea, effectively building a map of in-water turtle hotspots,” Hart said. “The more we know about their habitat use, the more questions are raised about their behavior and ability to adapt. We hope to build a better understanding of how frequently turtles return to these same locations, and whether or not they move to new habitats when those locations are impacted. This type of information would be extremely valuable for developing management strategies to help in population recovery.”

The study, “Movements and Habitat-Use of Loggerhead Sea Turtles in the Northern Gulf of Mexico during the Reproductive Period,” was published July 3 in the journal PLOS ONE.

Great whites use stored liver oil to power through ocean “road trips”

18 Jul
This is a juvenile great white shark at the Monterey Bay Aquarium. (Credit: Randy Wilder)

This is a juvenile great white shark at the Monterey Bay Aquarium. (Credit: Randy Wilder)

Bears, sea lions and whales rely on their external blubber to power through hibernations and migrations.

For them, a little extra flab is crucial to their survival.

Would a Great white shark be so intimidating if it was a little overweight? Probably not. It may instead get the stigma of a cop eating a doughnut with his mouth open.

But, like other large megafauna, Great whites migrate thousands of miles across the Pacific ocean  without eating much, and their lean physiques have puzzled scientists.

Where is the fat to fuel the trip stored?

A new study by scientists at Stanford University and the Monterey Bay Aquarium found that instead of storing fat externally, Great white’s instead store the fat in their liver, discounting the previous notion that the sharks would periodically dine throughout the voyage.

“We have a glimpse now of how white sharks come in from nutrient-poor areas offshore, feed where elephant seal populations are expanding – much like going to an Outback Steakhouse – and store the energy in their livers so they can move offshore again,” researcher Barbara Block, a professor of marine sciences and a senior fellow at the Stanford Woods Institute for the Environment, said. “It helps us understand how important their near-shore habitats are as fueling stations for their entire life history.”

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Sea turtles are Gulf travelers, scientists say

16 Jul
 Loggerhead “exchanges” between study sites. Tracks of satellite-tagged adult female loggerheads (Caretta caretta) 119941 and 119946 during the inter-nesting period in 2012 (A); tracks of satellite-tagged adult female loggerheads 108172 (2011) and 119940 (2012) during the inter-nesting period (B). doi:10.1371/journal.pone.0066921.g002

Loggerhead “exchanges” between study sites.
Tracks of satellite-tagged adult female loggerheads (Caretta caretta) 119941 and 119946 during the inter-nesting period in 2012 (A); tracks of satellite-tagged adult female loggerheads 108172 (2011) and 119940 (2012) during the inter-nesting period (B).
doi:10.1371/journal.pone.0066921.g002

Gulf Loggerheads were always thought to be homebodies.

After the females nested, they would make a home at their local beach. They would never travel too far from familiarity.

But, these  threatened female loggerheads are more curious than scientists once thought.

A new study suggests that the turtles nest in different places–laying eggs on the coast of Louisiana one week and traveling hundreds of miles to make another home in Florida weeks later.

The authors of the U.S. Geological Survey study say that the travel routes–which may be littered with leftover oil and increased predators–pose a greater risk to the sea turtle population. The conservation efforts may need to be modified to reflect the findings.

“The satellite data and our observations on the ground tell the same story: loggerheads in this subpopulation nest at multiple beaches, sometimes hundreds of miles apart,” lead author Kristen Hart, a USGS research ecologist, said.

Co-author and USGS biologist Meg Lamont said that simply protecting beaches that are known to be highly populated with sea turtle nests may not be enough.

“These data show it is not sufficient to just protect habitat around high density nesting beaches – such as the St. Joseph Peninsula – because many turtles that nest on the Peninsula use the entire region from the eastern Florida Panhandle to Louisiana,” said Lamont.

Hart said she and her team are continuing to map out the travel routes by tagging the turtles.

“We are working towards defining areas where sea turtles concentrate their activities at sea, effectively building a map of in-water turtle hotspots,” Hart said. “The more we know about their habitat use, the more questions are raised about their behavior and ability to adapt. We hope to build a better understanding of how frequently turtles return to these same locations, and whether or not they move to new habitats when those locations are impacted. This type of information would be extremely valuable for developing management strategies to help in population recovery.”

The study, “Movements and Habitat-Use of Loggerhead Sea Turtles in the Northern Gulf of Mexico during the Reproductive Period,” was published July 3 in the journal PLOS ONE.