Swordfish as oceanographers: Satellite tags facilitate research of ocean's 'twilight zone' off Florida

NOVEMBER 5, 2019

by Hannah Hickey, University of Washington

Researchers from the University of Washington are using high-tech tags to record the movements of swordfish—big, deep-water, migratory, open-ocean fish that are poorly studied—and get a window into the ocean depths they inhabit.

The researchers tagged five swordfish in late August off the coast of Miami: Max, Simone, Anthony, Rex and Oliver. Their movements can now be viewed in near-real time. And although swordfish are a prized catch, these ones aren't at higher risk, researchers say, since the website updates only every few hours and these fast-swimming fish spend most of their time far from shore.

"These are animals that migrate into the ocean's twilight zone that we know next to nothing about," said Peter Gaube, an oceanographer at the UW Applied Physics Laboratory. "Swordfish in different regions have very different behavior. We hope to learn more about these amazing animals and their environment as they migrate between regions."

This is the first time satellite position tags have successfully been placed on swordfish caught off the coast of the United States.

Continued

Mako Shark Phones Home, Revealing Epic Journey

By Nicholas Weiler, Live Science Contributor | August 31, 2015 08:45am ET

One of the toothy stars of "Shark Week" has phoned home after five months at sea, revealing that this longfin mako shark was a prolific and deep-diving swimmer.

On Valentine's Day, researchers from the United States and Cuba came together near Cojimar in northern Cuba to put a satellite tag on a rare longfin mako shark.

Remarkably, in the following five months, the mysterious deep-water shark swam 5,500 miles (8,850 kilometers), averaging 36.5 miles (58.7 km) a day. In April, the animal followed the Gulf Stream west into the Gulf of Mexico, then looped back north and east through the Bahamas in May, and into the deep Atlantic Ocean. In June, the shark circled as far north as the coast of New Jersey, before traveling southeast toward Virginia's Chesapeake Bay. There, the animal's satellite tag detached (as it was programmed to do) in mid-July and started calling in the shark's travelogue, to the excitement of the researchers.

Read on ...

Smaller satellite sensors help scientists follow young endangered turtles - via Herp Digest

Margaret Badmore, Science/ Endangered Species, 5/12/15, Treehugger

Marine biologists have been studying the movement and habitats of loggerhead turtles using satellite tags for some time. But in the past, they were only been able to follow the movements of adults, because the transmitting devices were too big to attach to younger, smaller turtles. So, the travels of younger turtles are not well understood.

But now, the technology has improved and the transmitters have gotten smaller. Last month, National Oceanic and Atmospheric Administration (NOAA) scientists outfitted an adolescent turtle named Coco with a satellite tag and released it back into the wild. Coco is the first adolescent loggerhead to be tracked on the West Coast.

Coco was originally picked up by the Coast Guard, because it (the turtle's sex is undetermined) appeared to need medical attention. When veterinarians deemed the turtle healthy enough to be returned to the sea, they decided to use the occasion to tag it with a tracker. Coco was released 50 miles off the coast of San Diego, by scientists Tomo Eguchi and Jeff Seminoff on April 15. The turtle was about the size of a dinner plate, and as an adult may grow up to three feet in length.

“We know that there are juvenile loggerheads in this part of the Pacific, but they’re small and very hard to spot,” said Eguchi in a statement. “So we don’t have good data on what types of habitat they’re using.”

Tracking the turtle will help protect this endangered species. Scientists know that the young turtles sometimes share territory with swordfish, because the turtles have gotten caught by the gillnets used by fishermen. NOAA has established a Pacific Loggerhead Conservation Area off the shores of Southern California. Turtles are thought to swim in these areas when the water temperature is higher. Last summer, conservation managers closed the area to fishing for the first when water temperatures rose. Gathering more data on the young turtle’s movement will help better predict when fishing should be prohibited.

A number of young turtles have also been tracked in the Atlantic ocean. Another challenge to tracking the young turtles has been that their shells aren’t a reliable spot to stick sensors, because the fast growing shells stuff them off. Last year, Dr. Kate Mansfield published some surprising findings after figuring out that using an acrylic base coat is the best way to attach something to the turtle’s keratin shell—much like attaching a fake nail. Mansfield learned that the young turtles spend time in the calm waters of the Sargasso Sea, when it was previously believed that they followed the currents of the North Atlantic Gyre all the way to the Canary Islands.

Hopefully Coco will help us better understand how turtles travel around the Pacific. We can all follow the turtle’s journey, which so far has covered over 435 miles.

Smaller satellite sensors help scientists follow young endangered turtles - via Herp Digest

Margaret Badmore, Science/ Endangered Species, 5/12/15, Treehugger

Marine biologists have been studying the movement and habitats of loggerhead turtles using satellite tags for some time. But in the past, they were only been able to follow the movements of adults, because the transmitting devices were too big to attach to younger, smaller turtles. So, the travels of younger turtles are not well understood.

But now, the technology has improved and the transmitters have gotten smaller. Last month, National Oceanic and Atmospheric Administration (NOAA) scientists outfitted an adolescent turtle named Coco with a satellite tag and released it back into the wild. Coco is the first adolescent loggerhead to be tracked on the West Coast.

Coco was originally picked up by the Coast Guard, because it (the turtle's sex is undetermined) appeared to need medical attention. When veterinarians deemed the turtle healthy enough to be returned to the sea, they decided to use the occasion to tag it with a tracker. Coco was released 50 miles off the coast of San Diego, by scientists Tomo Eguchi and Jeff Seminoff on April 15. The turtle was about the size of a dinner plate, and as an adult may grow up to three feet in length.

“We know that there are juvenile loggerheads in this part of the Pacific, but they’re small and very hard to spot,” said Eguchi in a statement. “So we don’t have good data on what types of habitat they’re using.”

Tracking the turtle will help protect this endangered species. Scientists know that the young turtles sometimes share territory with swordfish, because the turtles have gotten caught by the gillnets used by fishermen. NOAA has established a Pacific Loggerhead Conservation Area off the shores of Southern California. Turtles are thought to swim in these areas when the water temperature is higher. Last summer, conservation managers closed the area to fishing for the first when water temperatures rose. Gathering more data on the young turtle’s movement will help better predict when fishing should be prohibited.

A number of young turtles have also been tracked in the Atlantic ocean. Another challenge to tracking the young turtles has been that their shells aren’t a reliable spot to stick sensors, because the fast growing shells stuff them off. Last year, Dr. Kate Mansfield published some surprising findings after figuring out that using an acrylic base coat is the best way to attach something to the turtle’s keratin shell—much like attaching a fake nail. Mansfield learned that the young turtles spend time in the calm waters of the Sargasso Sea, when it was previously believed that they followed the currents of the North Atlantic Gyre all the way to the Canary Islands.

Hopefully Coco will help us better understand how turtles travel around the Pacific. We can all follow the turtle’s journey, which so far has covered over 435 miles.

Scientists employ satellite tags to solve whale-sized mystery

Date:

November 14, 2014

Source:

Wildlife Conservation Society

Summary:

For the first time, scientists working in the waters of Patagonia are using satellite tags to remotely track southern right whales from their breeding/calving grounds in the sheltered bays of Península Valdés, Argentina, to unknown feeding grounds somewhere in the western South Atlantic.

Continued ...

Satellite tagged green turtles reveal shortcomings in marine protection areas

Unique research by scientists from Deakin University in Victoria, Australia, has been using satellite tracking to monitor tagged green turtles in the Indian Ocean.

The findings indicate that even the largest Marine Protection Areas (MPAs) – some covering hundreds of thousands of square kilometres of sea – may need to be buttressed with smaller networks of protected areas.

It has been discovered that the turtles travel much further from their breeding grounds than previously suspected to forage for food.

The international team from Deakin, Swansea University in Wales and the Seychelles located green turtles nesting ashore at night and fitted them with satellite tags.

They then used satellites to monitor their movements in the Chagos Archipelago in the Indian Ocean, one of the largest protected marine parks in the world, covering 640,000 sq km, and renowned for its pristine coral reefs and schools of endangered species.

“Over the last few years, governments around the world have declared some massive marine parks, typically around ocean islands,” said Prof Graeme Hays, Deakin Chair of Marine Science. “How well these protect marine life has been heavily debated.”

Continued

Great white shark's epic ocean trek

By Paul RinconScience editor, BBC News website

A great white shark called Lydia is about to make history as the first of its species to be seen crossing from one side of the Atlantic to the other.

The satellite-tagged 4.4m-long female is currently swimming above the mid-Atlantic ridge - which marks a rough boundary line between east and west.

Lydia was first tagged off Florida as part of the Ocearch scientific project.

The shark has travelled more than 30,500km (19,000 miles) since the tracking device was attached.

Dr Gregory Skomal, senior fisheries biologist with Massachusetts Marine Fisheries, told BBC News: "No white sharks have crossed from west to east or east to west."

Lydia is now roughly 1,600km (1,000 miles) from the coasts of County Cork in Ireland and Cornwall in Britain, and nearly 4,800km (3,000 miles) from Jacksonville, Florida, where she was tagged by scientists in March 2013.

Continued

Satellite Tagging Maps the Secret Migration of White Sharks

Apr. 4, 2013 — Long-life batteries and satellite tagging have been used to fill in the blanks of female white sharks' (Carcharodon carcharias) lifestyles. Research published in the launch edition of BioMed Central's open access journal Animal Biotelemetry defines a two year migratory pattern in the Pacific Ocean. Pregnant females travel between the mating area at Guadalupe Island and nursery in Baja California, putting them and their young at risk from commercial fishing.

White sharks are pelagic much of their time, living in the open ocean. However they are also philopatric, in that they return to the same place to find a mate. This commute can be far-ranging, including the Hawaiian Islands, California, and Mexico but while males have been reported returning yearly to mating sites, the behavior of females has before now been more secretive.

Dr Michael Domeier and Nicole Nasby-Lucas from the California based Marine Conservation Science Institute mapped the migration patterns of female white sharks using satellite-linked radio-telemetry tags.

Female white sharks were found to follow a two-year migration pattern with four distinct phases. Firstly the pregnant females left Guadalupe Island, Mexico and remained offshore for most of their 18 month gestation (on average 465 days). This pelagic area was much larger than the foraging area used by males and in fact the females tended to avoid the male's foraging area while the males were present.

The second phase was a two month sojourn in the coastal waters of Baja California where the sharks gave birth. After leaving the nurseries the female sharks began a migratory path back to Guadalupe Island in such a way as to avoid males until ready to reproduce. Finally the mating n phase at Guadalupe Island lasted up to four and a half months before the two year cycle began again.

Females that skipped a year of reproduction returned to the breeding site after only a single year migration.

Dr Domeier commented, "During the mating phase both males and female sharks are seen with injuries. It's unclear whether males are fighting over food or females or both, but this aggression may be why the females avoid males at other times. Our tracking has also highlighted a previously unknown period of vulnerability when the females are exposed to commercial fishing off the coast of North America."

Open access publisher BioMed Central is proud to announce the launch of Animal Biotelemetry. This journal joins our growing portfolio in ecology and conservation and marks a significant development in the area of Animal Biotelemetry research.

Continued:  http://www.sciencedaily.com/releases/2013/04/130403200154.htm