Sea turtle die-off

Hundreds of dead sea turtles could be headed for Costa Rica's northwestern shores, officials say

The population of the nearly extinct Eastern Pacific green sea turtle will likely be severely affected by the recent mass deaths, according to biologists. Longline fishing and a mass dynamiting are suspected killers.

At least 70 Eastern Pacific green sea turtles have been found dead since Sunday, with hundreds more reported offshore. This sub-species of sea turtle is critically endangered and, along with the hawksbill, is the most endangered type of turtle in Costa Rica. Courtesy of Widecast

Tico Times,

6 November, 2013

Hundreds of dead Eastern Pacific green sea turtles could be headed for the shores of Costa Rica's northwestern province of Guanacaste, say biologists and officials from the National System of Conservation Areas (SINAC).

At least 70 dead turtles were spotted on beaches and in shallow waters in northern Guanacaste on Tuesday, but reports from fishermen indicate that the death toll may be much higher.

“We have reports from fishermen whose boats are surrounded by hundreds of dead turtles,” Roger Blanco, the lead investigator for the Guanacaste Conservation Area with SINAC, told The Tico Times. “They say they are headed for shore.”

With its black shell and dark body, the rare Eastern Pacific green sea turtle sub-population is considered a separate species from the green sea turtle by some scientists. The sub-population is critically endangered both in Costa Rica and worldwide. 

According to data from the conservation group the Wider Caribbean Sea Turtle Network, or Widecast, the population of Eastern Pacific green sea turtles has declined by 40 percent in the last several years in Costa Rica’s Golfo Dulce, in the southern Pacific, where at least 280 Olive Ridley turtles died in a mismanaged longline fishing expedition in January. Little data is available on Guanacaste’s green sea turtle population. 

“This type of turtle is nearly extinct,” said Didiher Chacón, the Costa Rican director of Widecast. “The death of this many turtles is extremely severe for this species. We don’t know if the population can survive a massive loss like this; at the very least it will extremely hurt the population.”

Two badly wounded turtles were pulled from the carcasses and taken to the National University (UNA), north of the capital, in an attempt to save them. Veterinarians were able to save one of the turtles, which will be released tomorrow in the coastal province of Puntarenas. The other turtle died on the operating table.

UNA veterinarians are now studying some of the dead turtles to determine causes of death. The results are expected within the next two days, but Widecast workers found turtles with longline hooks in their mouths and others that had sustained blows to the head.

“This is very simple. If a turtle has a hook in its mouth, if it has been hit in the head, then it didn’t die of natural causes,” Chacón told The Tico Times. “Not all of the turtles had these types of injuries, and it is not fair to say that we are 100 percent sure that it was fishing in every case, but this is basic deduction.” 

According to Blanco, northern Guanacaste has had a successful mahi mahi season, increasing the number of longline fishermen in the area. Longline fishing is legal in most of Costa Rica and is used primarily for catching mahi mahi. Although longliners are the main suspect for most environmental agencies, an official from the Costa Rican Fisheries Institute (Incopesca) has another theory.

Roberto Umaña, the head of Incopesca in Guanacaste, told The Tico Times in an interview that he has seen no evidence that would point to longline fishing. Later, in an email, Umaña revealed another suspect: dynamite. Some turtles were found swimming in circles as if they were dazed, Umaña wrote. According to the Nicaraguan Newspaper La Prensa, there was an incident of dynamite fishing in San Juan del Sur, just north of Playa Jobo in Costa Rica, where a number of dead turtles appeared, in September.

This story is developing. Read an update on the investigation into the turtle deaths here.

‘Astonishing’: World’s rarest whale spotted near Canada’s Pacific coast

• “First confirmed sighting in recent history”
• Two seen in last few months after none in 60+ years
• Some “migrate to the area around Japan”
• “Nasty looking but healed wound” on upper jaw

ENENews,

6 November, 2013

Vancouver Sun, Oct. 31, 2013: Second sighting of endangered North Pacific right whale in B.C. waters in 62 years [...] “It’s exciting, kind of astonishing, really, to have two different animals sighted four months apart on our coast when there haven’t been any confirmed sightings for the last 62 years,” [John Ford, head of the cetacean research program at Pacific Biological Station in Nanaimo] said in an interview Thursday. “We were uncertain whether the species still occurred in Canadian waters and this clearly shows that they do.” The right whale, observed with a group of humpbacks, had a “nasty looking but healed wound” on the upper jaw, “very likely from a previous entanglement in fishing gear that he evidently survived,” Ford explained. [...] Federal biologist James Pilkington made the first confirmed sighting in recent history of a right whale in B.C. waters on June 9, 2013, aboard the Canadian Coast Guard vessel Arrow Post off the west coast of Haida Gwaii. That whale was observed for a total of 17 hours over a few days feeding at the surface on copepods, zooplankton measuring about 10 millimetres. Only about 30 right whales are thought to exist in the eastern North Pacific. The last previous B.C. sighting dated to 1951 [...]

LiveScience, Nov. 6, 2013: This is the second North Pacific right whale spotted in the area since June, an astonishing fact given that the last sighting before that was in 1951, [...] North Pacific right whales, are incredibly endangered, with only 50 thought to live in the waters of the region. Another 200 or so are thought to migrate to the area around Japan for the summer, but are considered a distinct population'

Huffington Post, Nov. 1, 2013: Right Whale Sighting: World’s Rarest Whale Seen Near Victoria[...] Considered the rarest whale population in the world, the North Pacific right whale is not often spotted. But for the second time since 1951, the majestic creature was seen in B.C. Waters.

More photos here

See also: Gov’t scientists unsure why rare giant fish washing up dead on West Coast, “testing tissue for radiation” — “One dead oarfish is odd, two is a pattern”