Commercial Tuna Netting in Osa´s Blue Water Pelagic By Shawn Larkin
A version on this artical appeared in The Tico Times, Central America´s largest English language newspaper, in 2008. Check out www.ticotimes.net.
The most high tech, large scale fishing going on in Costa Rica’s oceans is commercial tuna fishing. From hard working crew to helicopters, to radar to satellites, to air conditioning to internet-these operations take catching fish very seriously. They drop enormous nets bigger than a city block down into the sea to catch vast quantities of an assortment of marine life. They are mostly after tuna, the fish with one of the highest resale value of any denizen of the deep.
When fishing boats find a big group of spinner dolphins they find some of their ever-present sidekicks; like giant yellow fin and big eye tuna. The tuna are mostly only to be seen below the surface and would not be so easy to locate without the help of dolphins, who must surface regularly to breathe. The giant tuna are packed together around the dolphins making sure they don’t lose the dolphins, who find their food for them. Here in the offshore Osa, the big tuna and the spinner dolphins are always together.
I reckon the dolphins are thinking now that the moon is full and the current is from the southwest at two knots, and the wind is calm, and there is a big spaced swell coming in from west southwest and it rained last night and the layers of water temperatures changed a lot last night, and it’s a sunny day almost high noon, and I think I know where all those other dolphins are going, and the orcas will not hunt today, and the tuna boats will be busy for a few hours (hope my friends and family make it out), we should go hunt the south end of the Osa drop off upwelling.
I reckon the tuna are just thinking mostly one thing-follow the dolphins.
Follow the dolphins. Just like the sea birds, and the sailfish and the marlin, and the sharks and the whales and the sport fishing captains and the commercial tuna fishing fleet. Follow the dolphins, they have the best actionable ocean intelligence. The dolphins have the network, they are always with the food.
In the Osa drop off upwelling, the tuna, birds and other marine life are nearly always with the dolphins so all a commercial fishing fleet has to do is find the birds on a special bird radar, send up a helicopter or two to check it out, call in coordinates, start corralling the dolphins with the helicopter and explosives dropped from the helicopter, put down small fast chase boats to further corral the dolphins, use the ship to corral the dolphins even more, and then put down a very big net around the dolphins and associated marine life with the help of a special net boat.
If you do this you get a lot of tuna in the net below the dolphins and it´s worth a lot of money. Sadly this kind of bonanza is unsustainable.
Unfortunately, the longer lived more slowing reproducing spinners will probably die out before the tuna is exhausted, perhaps giving the tuna a chance to recuperate because then no one will be able to find tuna. Except how will the tuna find food without the dolphins?
One knowledgeable source has told me that around thirty spinner dolphins are killed each day by each busy boat. They die most frequently when their narrow smiling mouths get stuck in the holes of the net. Hundreds more must be manhandled by diving crew and thrown out of the nets daily lest the nets are damaged. The freed spinner dolphins are often damaged and freaked out.
Other species of dolphins here in the Osa blue water drop off upwelling area, like bottlenose and spotted dolphins are somewhat more likely to swim out if a small piece of one end of the net is put down for awhile, a procedure known as a “backdown.” A backdown does not help Osa´s spinner dolphins though. Here in Costa Rica the dolphins stay in the net.
The atuneros say the spinners are tontos, idiots because they do not swim away from the boat and out of the net. They seem unable to stop surfing the waves of the ship. The same trait the tourist boats love dooms the poor spinners. They keep swimming with the boat and thus in the net, requiring sometimes all available crew to get in the water and get the netted dolphins out of the tuna catch.
One tuna boat mariner told me that industry supplied and paid biologists, part of whose job is check dolphin safety, always know when to look away, and that the biologists never look at what´s happening underwater, where the real carnage takes place. Biologists more concerned about the dolphin than the tuna quickly lose their jobs. Biologist interns from universities and other independent non-biased sources would provide a better check and balance.
The tuna boat divers get to wrestle marlin, sailfish, whale sharks, other sharks, turtles, dolphins and much more daily. Tourist divers are not even allowed to get in the water too near dolphins. I´m sure some tourists would pay to get to wrestle the animals too.
It could be bigger than commercial tuna fishing. Think on it. Get to molest, harass, ride and throw around big tough animals. Maybe even on TV.
Seriously, what would really benefit the commercial tuna fishing industry is a park that produced big fish for nearby waters. For many years around the world marine protected areas have proven to increase catches in the surrounding area. With a big enough pelagic park, or better still parks and corridors, los atuneros could make money in the long term, not just short.
If no open ocean parks are created many elements of the Tico commercial fishing fleet will exterminate themselves as commercial fishing fleets have the world over in one collapsing special place after another. One Tica marine biologist told me she saw some commercial fishing charts that showed every single sector of Costa Rica´s oceans labeled as different kinds of fishing areas, all with declining catches. It´s time to set aside a meaningful, not minuscule, part of Costa Rica´s biggest ecosystem, the pelagic. Farms at sea might be only part of the solution; there must be pelagic parks for tuna fishers, dolphin tourism and spinner dolphins to survive.
Copyright 2009 Shawn Larkin