Tuesdays with Turtles – Must See TV Edition

Read stuff like this (hat tip to my mom for telling me about this report she’d seen on TV in Madras), and you begin to doubt your utility as a scientist.
IBNLive : Orissa turtles neck-deep in danger

Nearly 3,000 Olive Ridley turtles have died off the Orissa coast this season. Beaches have become turtle graveyards.

Orissa is one of the three places in the world where the Olive Ridleys come for their annual mass nesting.

Mechanised trawlers are the biggest culprits for this slaughter. When the trawlers go to the sea, turtles are trapped in their fishing nets. The turtles are unable to disentangle themselves and suffocate to death.

See the video report too. In her own breathlessly indignant style, the reporter explains the science behind turtle excluder devices (well known and established), the regulation expressely forbidding shrimp trawling close to the coast, especially during the arribada, the money set aside in the budget to purchase a few speed boats for the coast guard, who are well aware of the problem, so wot’s, uh, the deal?

The investigative reports contradict each other, the first one linked said there was no patrolling, the second one gushingly praises the coast guard for vigorous enforcement and patrolling, so which is it? I need to find out, call on some old friends… But clearly, there are issues if net catch mortality is on the rise.

The three pillars of any regulatory action are the science, the policy, and the implementation. The science here is very clear (though the US administration seems to not think so any more?), shrimp nets with turtle excluder devices cause decrease in mortality. The policy is clear, use these nets when shrimp fishing, and completely ban fishing activity during the arribada (the number of turtles in an arribada, 50000 in a night and perhaps 300000-400000 over the course of a week is staggeringly large, so, shrimp net or not, you’ll kill a lot of turtles just by being there).

So, like anything else in India, where is the implementation? The people running the trawlers know they are illegal anyway, so they don’t bother with the TEDs. The owners of the trawling boats never face the consequences, only the poor hapless fishermen running the boats. No attempt is made to coopt the people being regulated, it is a top down “we tell you what to do” kind of situation where the law is selectively enforced, no explanations are given, the regulation may just be an excuse to get some kickbacks. The fishermen see the excluder device as an inconvenience as they are not shown how to use it. Some low level bureaucrat in charge of buying high speed boats for the state’s forest service either does not realize the importance of getting this policy on the road, or is on the take. You can pick any, or all of these reasons and you’ll see why just like most other things in India, the road to hell is paved with good intentions 🙁

Why be a scientist and come up with cool new techniques to do things when you don’t pay equal attention to the implementation of techniques invented 20 years back? As a responsible scientist, I must look at policy and implentation with as much interest and passion as I look at the science – New career paths?

ScienceDaily: Scientists Warn Of Climate Change Risk To Marine Turtles

North American marine turtles are at risk if global warming occurs at predicted levels, according to scientists from the University of Exeter. An increase in temperatures of just one degree Celsius could completely eliminate the birth of male turtles from some beaches. A rise of three degrees Celsius would lead to extreme levels of infant mortality and declines in nesting beaches across the USA.

Here’s the paper.

Like a lot of other reptiles, the sex of the hatchling is dependent on nest temperature. Warmer temperatures make female turtles (my mnemonic was hot females!), and even warmer temperatures just kill the eggs. But, I wonder if the turtles would adapt by nesting a little earlier. I don’t think it is yet clear when turtles decide to nest. If it is based on sea temperature, then they would eventually figure it out. This paper from 2004 appears to conclude that loggerheads in Florida do nest earlier than before, so there is hope.

John F. Weishampel, Dean A. Bagley, Llewellyn M. Ehrhart (2004) Earlier nesting by loggerhead sea turtles following sea surface warming Global Change Biology 10 (8), 1424–1427

The onset of spring, noted by the timing of wildlife migratory and breeding behaviors, has been occurring earlier over the past few decades. Here, we examine 15 years of loggerhead sea turtle, Caretta caretta, nesting patterns along a 40.5 km beach on Florida’s Atlantic coast. This small section of beach is considered to be the most important nesting area for this threatened species in the western hemisphere. From 1989 to 2003, the annual number of nests fluctuated between 13 000 and 25 000 without a conspicuous trend; however, based on a regression analysis, the median nesting date became earlier by roughly 10 days. The Julian day of median nesting was significantly correlated with near-shore, May sea surface temperatures that warmed an average of 0.8°C over this period. This marine example from warm temperate/subtropical waters represents another response of nature to recent climate trends.

So the truth lies somewhere between easy adaptation and giant swarms of frustrated female turtles!