How to Not Catch a Sea Turtle

Lekelia D. Jenkins, a postdoctoral researcher at the University of Washington, writes from Ecuador, where she is studying factors in the cross-cultural adoption of marine conservation technologies like turtle excluder devices and circle hooks. She co-leads this project with Patrick Christie, who is an environmental sociologist and associate professor at the University of Washington.

Sunday, March 13

In the wake of the tragic earthquake in Japan, Ecuador was one of many coastal nations that began evacuating coastal regions in case of tsunamis. Thankfully, we were out of harm’s way. Two days before the earthquake we returned from the coast to deal with some visa issues, and our trip back to the coast the day before the earthquake was fortunately delayed.

While we were not among the masses of people trying to move inland, the evacuations still created major problems for our project. We had hoped to begin collecting data in Puerto Bolivar on Friday. The state of emergency was lifted on Saturday, but we decided to postpone data collection until Monday, because the roads would be full of people returning to their houses, and once back in their hometowns they would be too busy checking on friends, relatives and property to take our survey. We heard that many of the fishermen moved their boats to other ports or took them farther out to sea. We aren’t fully confident that things will be back to normal by Monday, but we will travel south to Puerto Bolivar and hope for the best. Meanwhile, the team is waiting in Guayaquil and using the time to tidy up loose ends.

For Mark Mizrahi, one of the research assistants, the loose end was creating the code books with consultation from Richard Pollnac, an adviser to our project. Mark’s main job is to code the completed surveys. The process of coding involves taking answers and condensing them into a numerical code. It is critical that the coding process be as accurate as possible, because this is the data we will ultimate analyze. The code book is in essence a glossary that helps ensure accuracy and clarity in the data.

The first step to making a code book is to reduce questions to abbreviations of no more than eight letters. For example, “What are five good things about turtle excluder devices?” becomes FIVEGOOD. Associated with each abbreviated question are numerical codes for the answers. Simple yes-or-no answers will be assigned a value of 0 for “no” and 1 for “yes.” For more descriptive answers — like those we will get in response to FIVEGOOD — Mark will create a new code for each new answer we receive from survey-takers. For instance, “They save turtles” will be assigned a 1; “They get debris out of the net” would be given a 2, and so the list would grow with each new answer. For our survey, Mark will create about 150 question abbreviations and hundreds of answer codes. In order to make sense of it all, intuitive abbreviations are extremely helpful. Being a creative type, Mark is quite good at this. Now that you know what FIVEGOOD is, you should have no problem with the equally intuitive FIVEBAD. If you want a bit more of a challenge, try deciphering these (hint: they all pertain to fishermen’s use of turtle excluder devices): YRSUSED, FRSTLERN, FRSTEXP, BRKRULE, BRKHOW.

Another loose end is this post. I’ve been remiss. Since the first post I’ve mentioned turtle excluder devices (TEDs), but I’ve told you little about why they are needed or how they work. It’s time to remedy that. I’ve written a lot about one of the case studies for this project: long-line fisheries and their use of circle hooks and dehookers to prevent sea turtles from drowning on fishing lines. Our second case study for this project is another fishery that can be harmful to sea turtles: shrimp trawling.

Shrimp and sea turtles often live in the same habitat — specifically, warm coastal waters. Shrimpers will pull nets in these waters for hours at a time. When sea turtles encounter these nets, some may be unable to surface, and they drown. In the early 1980s government scientists and shrimpers worked to reduce this threat, which resulted in the invention of the turtle excluder device. A TED is literally an escape hatch in the net. It consists of a metal grid (imagine a very large and sturdy grid from a charcoal grill). This grid is sewn at an angle into the narrow part of the net. Anything entering the net must encounter this grid, which selectively removes things based on size. Small items like shrimp pass through the grid bars and into the end of the net. Large items, like sea turtles, are blocked by the grid and directed by the grid’s sloping angle to an exit hole cut in the net.

How can the net still catch shrimp if it has a hole large enough to release a 1,000-pound leatherback sea turtle? The hole is covered by a flap of netting. With their large bodies, sea turtles easily push pass the flap, but shrimp don’t have the size or speed to exit the hole. Moreover, the narrow section of the net creates the underwater version of a wind tunnel, and the weak-swimming shrimp are like Ping-Pong balls that get swept through the TED and into the net. Here’s a short video, if you want to see a TED in action:

My final loose end for tonight is packing my bag for the three-hour road trip tomorrow to Puerto Bolivar. When next I write, I hope we’ll have our first data in hand. Wish us luck!