Tuesdays with Turtles – Archie Carr Edition

This is almost a 1000 juveniles killed in a year in Baja California alone. The authors mention that over 99% of all fisherpeople are employed in small scale fisheries, which surprised me.

PLoS ONE: Small-Scale Fisheries Bycatch Jeopardizes Endangered Pacific Loggerhead Turtles:

Although bycatch of industrial-scale fisheries can cause declines in migratory megafauna including seabirds, marine mammals, and sea turtles, the impacts of small-scale fisheries have been largely overlooked. Small-scale fisheries occur in coastal waters worldwide, employing over 99% of the world’s 51 million fishers. New telemetry data reveal that migratory megafauna frequent coastal habitats well within the range of small-scale fisheries, potentially producing high bycatch. These fisheries occur primarily in developing nations, and their documentation and management are limited or non-existent, precluding evaluation of their impacts on non-target megafauna.

This is a surprising and unexpected finding because you would expect smaller fishing boats to have smaller impacts. I guess smaller scale fishing fleets in Mexico (and other developing nations) have not been targeted for education, awareness and enforcement of turtle safe fishing practices.

The good news from the study is that a major source of mortality has been identified and the authors point to recent efforts to increase awareness in the community about turtle safe fishing. But it will be a long and hard fight to be tackled all over the world.

This article brings up some interesting information about sea turtle poaching in Mexico, including the fact that sea turtle eggs are considered aphrodisiacal in certain cultures…

Real Men Don’t Eat Turtle Eggs : To Fight Turtle Poaching, Campaigners Hit Below the Belt (By C.J. Bahnsen)

But there have been recent gains. WiLDCOAST, a small conservation organization also co-founded by Nichols, has implemented a media campaign. It started in 2005, when Argentine singer and Playboy model Dorismar attracted controversial attention by appearing in television and poster PSAs, hitting Mexican men—who eat turtle eggs mistakenly believing they are aphrodisiacs—below the belt. The message above a salacious Dorismar reads: “My man doesn’t need to eat turtle eggs; because he knows they don’t make him more potent.” The bold campaign reached a global audience of 300 million and resulted in a decrease in consumption of sea turtle eggs.

Well, the unfortunate thing about aphrodisiacs is that if you believe, it works! So, I guess a Playboy model telling you that sea turtles eggs are baloney may work. They author does say there was a decrease in consumption, but presumably, it is not quite that easy to ascribe causation relationships to particular parts of a campaign!

Other highlights…

Turtle smuggling is thought to be a proving ground, a gateway into drug trafficking. Mexico is the principal transit country for 70 to 90 percent of cocaine entering the U.S., and the largest outside source of
marijuana and methamphetamine.

This, I did not know.

Grupo Tortuguero continues its David-vs.-Goliath efforts to co-opt fishermen and volunteers from Baja’s fishing communities to monitor, tag and protect sea turtles. The group has dozens of sites along the peninsula and all have drug issues, ranging from trafficking to addiction. “I’ve interacted with fishers who were not ‘poachers,’ but were poaching for money to feed their habit,” says Nichols

The article is interesting because it points out the similarities between sea turtle smuggling and drug smuggling, the use of young women, the co-opting of users to become dealers, the bribery of local officials, the organization to avoid capture, etc. Hmm…

Since this is the Olive Ridley blog (hint, it is a sea turtle), I do write occasionally about sea turtles. this is a random bit of sea turtle news out of Texas, and it is a feel good story…

Sea Turtles Rescued From Chilly Waters – New York Times

At least three dozen juvenile sea turtles have been rescued from an arctic blast that caused the water temperature in an arm of the Gulf of Mexico to fall 18 degrees in 48 hours. The turtles, which are cold-blooded, were left comatose by the rapid temperature drop this week in the shallow bay where they feed. Animal rescuers feared that the cold would kill the turtles or make them so sluggish that they would be vulnerable to sharks.

The nice thing about sea turtle conservation is that they are good looking beasts, harmless and very accessible. Anyone who summers on the coast of North Carolina, for instance, can see at least a cordoned off area marked as a sea turtle nests. And they’re encouraged to keep watch for hatching, keep any eye on the nest, watch out for nesting turtles, etc. U.S sea turtle conservation has a long, and fairly successful history.

Here’s more on the green turtle.

Photo’s courtesy of NOAA’s fisheries website.

In case I forgot to mention, the Olive Ridley arribada started during the 2nd week of February, so about 50 days later, here they are, the “millions” of hatchlings.

The Hindu News Update Service

Olive Ridley hatchlings emerge in Gahirmatha

Kendrapara (Orissa), April 10. (PTI): Millions of tiny olive ridley sea turtle hatchlings are now emerging out of nests at the Gahirmatha beach in Orissa’s Kendrapara district, wildlife officials said on Monday.

The eggs laid by thousands of adult females in the Nasi-2 and Babubali islands in the Gahirmatha marine sanctuary have began to hatch over the last two days, they said.

Wildlife officials stationed at the nesting grounds were witness to the phenomenon, but tourists and researchers were not allowed into the unmanned territory close to the Wheeler’s island where a defence test range is located.

India’s intermediate range nuclear-capable missile Agni III is likely to be test fired from there some time this week, defence sources said.

You know what, the fact that this area is under close military supervision because of India’s grandiose missile dreams may not be sucha bad thing (sacrilege!!!). The area is under so much development pressure that even military operations are better than the alternative.

For more about the Gahirmatha area, visit the official website. At this point in time, the Arribada is very tourist unfriendly, and there are few, if any volunteering opportunities. I will keep any eye open for changes

Technorati Tags: olive ridley, sea turtles

An interesting paper featuring a North Carolinian turtle researcher Larry Crowder from Duke University:

Blackwell Synergy – Conservation Biology, Volume 21 Issue 1 Page 79 – February 2007 (Full Text)

Abstract: Although some sea turtle populations are showing encouraging signs of recovery, others continue to decline. Reversing population declines requires an understanding of the primary factor(s) that underlie this persistent demographic trend. The list of putative factors includes direct turtle and egg harvest, egg predation, loss or degradation of nesting beach habitat, fisheries bycatch, pollution, and large-scale changes in oceanographic conditions and nutrient availability. Recently, fisheries bycatch, in particular bycatch from longline fisheries, has received increased attention and has been proposed as a primary source of turtle mortality. We reviewed the existing data on the relative impact of longline bycatch on sea turtle populations. Although bycatch rates from individual longline vessels are extremely low, the amount of gear deployed by longline vessels suggests that cumulative bycatch of turtles from older age classes is substantial. Current estimates suggest that even if pelagic longlines are not the largest single source of fisheries-related mortality, longline bycatch is high enough to warrant management actions in all fleets that encounter sea turtles. Nevertheless, preliminary data also suggest that bycatch from gillnets and trawl fisheries is equally high or higher than longline bycatch with far higher mortality rates. Until gillnet and trawl fisheries are subject to the same level of scrutiny given to pelagic longlines, our understanding of the overall impact of fisheries bycatch on vulnerable sea turtle populations will be incomplete

Adult sea turtle killing by humans occurs due to

1. Harvest, killing them deliberately for food
2. Incidental bycatch in fishing nets
3. Habitat loss

The paper focuses on long line fishing and its effects on turtle mortality. So, if like me, you’re not a fisherperson, what is long line fishing and what are some other kinds of fishing techniques that have effects of sea turtles? Well, the Duke Project GloBal research team on studying bycatch has a nice primer. Some highlights:

1. Longlines: As the word suggests, longlines are very long (>10 km) lines of 2000+ individually baited hooks that drift close to the surface and are used to catch tuna, swordfish, halibut, etc. Crowder’s paper suggests that while each individual longline hook has low probability of catching a turtle, because of their number and ubiquitousness, they catch many many turtles.
2. Gillnets: These are giant rectangular mesh nets, either stationary or drifting, that catch marine life indiscriminately. There’s not much that can be done by way of reducingsea turtle catch in gillnets, except monitoring, observation and just using less of them
3. Trawls: Big funnel shaped bags that catch fish. Bottom trawling fishing boats used to, and still catch turtles at an alarming rate. Trawls are now (at least in the U.S and other “developed” countries) required to be outfitted with Turtle Excluder Devices (TEDS) to let turtles swim to safety.
4. Purse Seines: These are weighted on the bottom and float at the corners. They are indiscriminate, and especially hard on dolphins. It appears that mitigation efforts aimed at reducing dolphin mortality have the unintended effect of increasing sea turtle catch. Battle of the cute species!!

Take home message? Catching fish causes a lot of turtles to die. While trawl fishing is the worst culprit, it is also the most studied and the technique for which a viable mitigation strategy exists. THe other kinds of fishing are less studied, and there is precious little that can be done to avoid sea turtle bycatch.

Happy fishing!