Tuesday, May 2, 2023

Maldives wins maritime boundary dispute with Mauritius

Chart on how the Maldives-Mauritius economic zone was divided

Chart on how Maldives-Mauritius'overlapping territory will be divided


From Edition by Malika Shadid

Maldives' claim for a larger share of the disputed waters with Mauritius is upheld by the International Tribunal for the Law of the Sea (ITLOS).

Utilizing the equi-distance principle, ITLOS has made a determination to divide the disputed maritime zone between Maldives and Mauritius. 
However, the implementation of this principle has sparked controversy, primarily due to the necessary measurements that must be taken from Blenheim Reef to Mauritius.
 

Blenheim Reef, "Terra nullius" ?
 
Maldives has presented scientific evidence and satellite images to support their argument that the Blenheim Reef is not part of the coast of Mauritius.
In response to Mauritius' proposal to utilize the reef as a base point for drawing the equi-distance line, ITLOS' special chamber ruled it as inadmissible.
Despite being visible only during dry weather, the chamber has also decided to exclude any point from the Blenheim Reef while drawing the equi-distance line.

Maldives made an argument stating that the sovereignty dispute between Mauritius and the United Kingdom over the Chagos Archipelago was unresolved and fell beyond the purview of ITLOS's jurisdiction.
Despite Maldives' defense, ITLOS proceeded as required by the United Nations Convention on the Law of the Sea (UNCLOS), which grants each country a 200-mile continental shelf.
 
Blenheim reef with the GeoGarage platform (UKHO nauticalm raster map)
Blenheim Reef is a partly submerged atoll structure in the Chagos Archipelago, Indian Ocean.
It includes the coral reef of Baxio Predassa in its southeastern rim, plus another completely submerged part.

The disputed territory between the two countries covers an area of 95,000 square kilometers, and Mauritius proposed using the Blenheim Reef as a base point for dividing the border.
However, Maldives argued that the reef is not a dry land and thus cannot serve as a base point.
If it were considered as such, it would grant Mauritius an additional 4,687 square kilometers of territory, according to the proposed base point.

EEZ limits with the GeoGarage platform

ITLOS has allocated the disputed overlapping territory of 95,000 square kilometers between Maldives and Mauritius, providing each country with a 200-mile continental shelf.
Maldives has been granted 47,232 square kilometers while Mauritius has been given 45,331 square kilometers.

Mauritius received 0.960 square kilometers for every square kilometer received by Maldives.

Although the case has been resolved, it is worth noting that under the United Nations Convention on the Law of the Sea (UNCLOS), any natural extension of a country's continental shelf beyond 200 miles should be taken into consideration.
In 2010, the Maldives and Mauritius both approached the Commission on the Limits of the Continental Shelf (CLCS) to claim their share of the area beyond the 200-mile limit.
However, the matter remains unresolved at the CLCS.

Following the Maldives' independence in 1965, President Ibrahim Nasir entered into an agreement with Sri Lanka and India to divide the overlapping territories in the northern part of the Maldives.
However, the area of Chagos in the south has yet to be officially designated due to the British occupation of the islands.

On July 31, 1976, an agreement was signed between President Nasir's administration and Sri Lanka to separate the overlapping territory, and on December 28, 1976, a similar agreement was signed with India to separate the overlapping territory in the Arabian Sea.
However, the agreements did not come into effect until June 8, 1978. At the time of the agreements, none of the countries had a 200-mile special economic zone, so the overlapping territory was divided based on equidistance.

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Monday, May 1, 2023

Image of the week : evening on the roaring forties

 

EVENING IN THE FORTIES
Marion Dufresne (supply and oceanographic ship of the TAAF), between Crozet and Kerguelen

Sunday, April 30, 2023

Sailing winter Norway


Sailing winter Norway with small sail boat and Igor Stropnik

Saturday, April 29, 2023

Kirsten Neuschäfer is making history winning


Kirsten Neuschäfer (39) / South Africa / Cape George 36 - "MINNEHAHA" officially became the first woman to win a round the world race by the three great capes, including solo and fully crewed races, non-stop or with stops, and the first South African sailor to win a round-the-world event!
 
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Friday, April 28, 2023

Elephant seals take power naps during deep ocean dives

Data-driven animation showing the phases of a sleeping dive to 263 meters.
The phases of a seal’s sleeping dive to 263 meters, made using data captured by a device that monitored the seals’ brain waves, heart rates, dive depths and movement.
Video Credit: Animation by Jessica Kendall-Bar.

From NYTimes by Annie Roth

During the many months they spend at sea gorging on fish and squid, the massive mammals sleep only about two hours a day.

It long seemed as though African elephants were the champions of the all-nighter. 
They can get by on about two hours of sleep.
Other mammals need much more, like koalas (20 hours) or you (at least seven plus at least one strong cup of coffee).

But the largest living mammals on land have some competition at sea. Northern elephant seals are also able to sustain themselves on about two hours’ sleep, according to a study published Thursday in the journal Science. 
 
Cetaceans (whales and dolphins) and otariids (fur seals and sea lions) keep one side of their brains awake while the other is asleep (unihemispheric sleep).
In most other mammals, including phocids (true seals) and humans, both hemispheres of the brain are asleep at the same time.
Credit: Graphic by Jessica Kendall-Bar
 
The study found that Northern elephant seals sleep far less at sea than they do on land, and the z’s they do catch at sea are caught hundreds of feet below the ocean’s surface. 
The study’s authors believe that sleeping in the deep allows the seals to power-nap without being eaten by prowling predators.

Northern elephant seals, which are found along the West Coast, are champion divers that can descend to depths of 2,500 feet and stay under for about two hours.
They are not as big as elephants, but males can weigh as much as a car and stretch 13 feet long.
To maintain their blubbery bulk, Northern elephant seals must spend around seven months at sea each year, gorging on fish and squid.

During these epic voyages, the seals are vulnerable to predation by great white sharks and killer whales. Some marine mammals, such as dolphins and fur seals, can rest half of their brain at a time. 
This type of slumber, known as unihemispheric sleep, enables some mammals at sea to snooze with one eye open, literally, which prevents predators from catching them off guard. However, elephant seals sleep like us, shutting down their brains completely.

 
A sleeping 2-month-old northern elephant seal at Año Nuevo State Park, Calif.
Credit...Rachel Holser

Jessica Kendall-Bar, now a postdoctoral fellow at the Scripps Institution of Oceanography in San Diego, wondered how Northern ​​elephant seals managed to sleep, given how much time they need to spend eating and avoiding being eaten while at sea.

To find out how elephant seals avoid waking up in the maw of an orca or a shark, Dr. Kendall-Bar worked with colleagues at the University of California, Santa Cruz, to design a device that could monitor the seals’ brain waves, heart rates, dive depths and movement.
The device is noninvasive and fits atop the seal’s head like a swim cap.
The team attached the devices to the heads of several seals and monitored their sleeping habits for five days. 
The data collected by the devices revealed a bedtime routine unlike any other.
“They dive down, stop swimming and begin to glide,” Dr. Kendall-Bar said.
As they go deeper, their brain activity starts to slow.
“Then they transition to REM sleep, where they flip upside down and spin in a circle, falling like a leaf,” she said.

While in rapid eye movement, or REM, sleep, which is the deepest stage of sleep, the seals stayed upside down, oblivious to their slow descent.

After sleeping for around 10 minutes, the seals would suddenly wake up and make their way back to the surface.
During these sleep dives, some seals sank over 1,000 feet, sometimes finding themselves on the seafloor.
 
When elephant seals go into rapid-eye-movement (REM) sleep during deep dives, sleep paralysis causes them to turn upside down and drift downwards in a “sleep spiral.”
 This data-driven graphic shows sleeping postures every 20 seconds, with accompanying 30-second segments of EEG traces in the background.
Credit: Jessica Kendall-Bar

The seals Dr. Kendall-Bar and her colleagues monitored took several sleep dives each day, providing them with around two hours of sleep in total.
When Northern elephant seals haul out on land to breed and molt, they sleep for over 10 hours a day.
During that time, the seals aren’t eating, which may explain their need for extra sleep.

“Sleep is an adaptive trait,” said Jerome Siegel, a professor of psychiatry at the University of California, Los Angeles, who studies the evolution and function of sleep. “Animals have evolved to sleep in certain situations and not in others.” 
It makes perfect sense, Dr. Siegel said, that elephant seals would limit the amount of time they spend sleeping while at sea to make the most of their food intake and reduce the amount of time they are vulnerable to predators.

That doesn’t make seal sleep habits any less impressive.
“Northern elephant seals exhibit unparalleled flexibility in their sleep duration,” Dr. Kendall-Bar said. “No other mammal goes from sleeping about two hours a day for over 200 days to sleeping 10.8 hours a day.”

Dr. Kendall-Bar hopes her team’s findings will aid in the protection of marine mammals.
“Learning more about where, when and how marine mammals sleep at sea can help scientists improve the management of their critical resting habitats,” she said.

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