Shark Links: Nov 28, 2010

Sunday, November 28, 2010

Dolphin Safe Tuna

What is it good for? Absolutely nothing except for dolphins and their egos. If you want to get a head start on your reading, check out this article by Southern Fried Science: Dolphin-Safe Tuna: Conservation Success Story or Ecological Disaster?

If you do not know the story, many people were angered that tuna fishermen were killing dolphins. Many people urged them to do something about the number of dolphins killed, and eventually Dolphin-Safe Tuna was formed. That tuna is certified to not harm dolphins. The Dolphin sets find tuna where dolphins are whereas the Log sets and School sets find tuna using a floating object or locating them from a spotter plane. As SFS says:
If you do the math on this... you find that one saved dolphin costs 25,824 small tuna, 382 mahi-mahi, 188 wahoo, 82 yellowtail and other large fish, 27 sharks and rays, 1 billfish, 1,193 triggerfish and other small fish, and 0.06 sea turtles.
The main point of this is that the dolphins that people are protecting are causing even more lives to be lost. While the debate could go on about the relative value of a dolphin versus a billfish, there are more things to consider. Dolphins are not that endangered. The main species are either Data Deficient or Least Concern while many species that are killed because of Dolphin-Safe Tuna are threatened with extinction.

So, what does this have to do with sharks? Many of the species of shark that are caught because of Dolphin-Safe Tuna are threatened while dolphins and their egos are not. I hope this image will clear things up:

To end, I would like to thank Chuck for his plug on Shark Links:
Speaking of new blogs and links, those of who have missed the sharks and snark of The Chum Slick should check out Shark Links for shark news and occasionally NSFW commentary.
 If you would like to, check out Southern Fried Science and their blog Ya Like Dags?

---> Calvin Requin <---

---> Calvin Requin <---

Invasive Procedures

I was asked about this show by a certain Mr. B, and as I remember what the show was about, I remember the post by Sharky on the more-than-admittedly-sick Chum Slick. If you did not catch this show, it is no other than "Expedition Great White" on National Geographic. Below are some of the images from The Chum Slick on the show.

Should a hook like this be used?

Let's get to our "Battle Stations".
See that blood? That's normal.
This does happen to be an invasive procedure.
This is also an invasive procedure.
This research project is intended to understand sharks more by "[Catching] adult great whites, bring them on board their vessel, take DNA and blood samples and attach the most sophisticated tracking devices before setting them free." Pretty cool, right? Nope.
The subject of controversy is the way these sharks are brought on board of their vessel. The first thing they do is hook a shark using no other than a hook and bait. After the shark is tired out over a period of time, they bring it to the "shark elevator" which consists of a wood platform on the side of their boat. After the shark is raised out of the water it is sampled. The only thing left after that is to lower the elevator and let the shark go. Pretty safe, right? Nope.
There are many reasons why I do not like this type of research on great whites. For one, there is a huge risk associated with tiring out these animals. When these animals fight against being caught for a long period of time, they consume an extraordinary amount of energy. If you are aware, you will know that swimming and catching prey consumes energy. When the energy reserves of a shark are depleted to a certain level, they may not be able to replenish that energy if they do not have any energy to feed. It would be like sprinting ten miles out into the desert and find out that the nearest place to eat is a mile away from you. That would be the reason why catch-and-release is so dangerous for these animals. I also have a problem with the time that the shark is out of the water and how it is treated. It should take less than five minutes to perform this procedure, not tens of minutes or more. While Mr. Domeier refutes the possibility that these animals could be injured as a result of being held down on a hard wood surface, I think that these animals probably should not be taken out of the water. Physics is a little different underwater.

If you would like, you can check out the Q&A with Mr. Domeier.

On the National Geographic website for the show, there is the quote:
Captain Brett McBride, Dr. Michael Domeier and crew members, David Olson and John Reed attach a tracking antenna to the dorsal fin of a great white shark. This allows them to follow the patterns of how they live, die and mate.
I can pretty accurately depict how they live, die, and mate from this show. They live ordinary lives until they are caught and prodded by these amateurs, slowly die because of it, and mate with their claspers and cloacas.

Are their tails supposed to bend like that?

If you would like to, you can play the Expedition Great White Game. It consists of bad programming, bad graphics, and a very unrealistic depiction of what actually happens.

If this kind of treatment a critically endangered species should endure is professional, I am not impressed.

---> Calvin Requin <---

---> Calvin Requin <---