Tuesday, August 15, 2006

California moves to protect ocean ecosystems

The California Fish & Game Commission moved closer to protecting ocean ecosystems.

As debate continued late into Tuesday night, the protection plan was taking shape. California is close to final action in creating an historic network of marine protected areas that restrict or eliminate fishing along the state's central coast region. Streaming video or tape of the debate available here, including public comments. It's fascinating to watch this history being made.

With all the bad news about ocean decline, creating some areas where fish can reproduce unmolested is a necessary step in ensuring there are fish in our future ocean. Even where declines are not caused by fishing, it's a good idea to let depleted fish populations have some refuge areas so they can do their best to survive global warming and hypoxia, etc.

Many fishermen are incensed about Marine Protected Areas, believing that we have a right ot fish anywhere. But come on fellas, be reasonable. Freshwater refuges have been around a long time and they enjoy wide support among fishermen. Why not in the ocean? Fishing regulations are often a haphazard and piecemeal effort to protect fish, and we all know the patchwork of regulations frequently fail to achieve their goals. Refuge areas are a common sense idea whose time has come.

MPAs work, and let's all rise about our personal interests and embrace the strong medicine needed to ensure that we give fish a chance in the non-pristine oceans of our future.


Anonymous said...

I'm all for MPAs, they are a great tool for maintaining sustainable fish populations. But its important for us to remember, and teach those who are less fish saavy, that MPAs don't work for every fish. For example, MPAs don't protect highly migratory fish. The fish has to stay in the MPA to be protected. On the other hand, MPAs might still help those highly migratory fish by protecting their prey species. Maybe MPAs are like all you can eat buffets... I digress.

So a fish has to stay in the general region of an MPA to be protected. But what about the future of the MPA? Fish don't live forever. So the fish living in the MPA need to be able to reproduce there and the larvae need to be retained there. It's very important to look at the physical oceanography of the MPA and surrounding area. If no larvae are retained in the area, will there be recruitment of juveniles or adults back to the MPA to maintain the population?

Another often cited benefit of MPAs it to act as a source of fish to the area outside of the MPA, fish that can be harvested. If that is a motivation in establishing the MPA, we again need to examine the physical oceanography to see if the their will be physical transport of larvae out of the MPA.

So the moral of my rambling story is that while MPAs can be great tools, it is important to examine the fish species being targeted and the physical characteristics of the potential MPA site.

Mark Powell said...

No disagreement here, MPAs are not magic bullets that save all fish. MPAs need to be tailored to management goals if they are to be successful.

However, I do not think that fish have to stay always inside of MPAs to realize some benefit. If they spend part of their lifetime in an MPA, fish can be exposed to reduced fishing effort overall, and may experience reduction in "lifetime F" (lower lifetime risk of being killed by fishing). Lower lifetime F means greater life span and likely greater reproductive output, which is a clear benefit.

Also, fish may choose to stay in an MPA even if they're capable of moving, if the ocean ecosystem in the MPA is healthier and food is more abundant or habitat is in better shape.