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Revamping Closure Strategy Could Produce Long-Term Benefit

The same old, same old is not a viable alternative.

April 25, 2014
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conservation rip

conservation rip

Photo Courtesy of Michael Patrick O’Neill/Alamy Photo Courtesy of Michael Patrick O’Neill/Alamy

After reading this, those who know me will think I have lost my mind. Some of those who don’t know me will be sure I never had a mind in the first place. I don’t look at it as changing my stance on this issue, but rather as fine-tuning my previous position. I have not supported the idea of arbitrarily setting aside marine reserves, and I still do not support it. However, I have come to believe that strategically placed marine protected areas might be the only way to make sure some species remain sustainable and that their age distribution curve somewhat resembles that of an unfished stock.

During my tenure on the New England Fishery Management Council, my first committee assignment in 2004 was on the Habitat Committee, which was just beginning to wrestle with updating the Essential Fish Habitat plan. After nine years, I am no longer on the NEFMC, but the process to get the amendment done still struggles along. There are a number of reasons for this, but one among many was the desire to incorporate a ­re-evaluation of the groundfish closed areas and closures at the same time.

It made a lot of sense to me then and still does today, since at least some of the areas should be coincidental. It does complicate the process, however, and it is unlikely that anything will be in place until 2015. Listening to the public testimony and scientific ­discussions on the pros and cons of habitat, spawning and ­mortality ­closures began to make me think differently about the value of well-designed marine protected areas. Also, some of the topics that I have written about in past columns came back into play in my reasoning.

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Middle Ground

Opponents on one extreme believe that closed areas have not worked at all. If they had, they argue, the stocks would have recovered, and they haven’t. First, there were no de facto closed areas in the Gulf of Maine, the area most important to the recreational groundfish fleet. There were/are a series of gear-restricted areas and seasonal spawning closures. There is no place for the big old females (BOFs) to hide, and they are critical to future recruitment of fish stocks. It also became curious to me that many of those arguing that closed areas do not work were the very ones benefiting from substantial closed areas on Georges Bank. These were primarily established to protect spawning haddock. Initially, one area was not big enough to prevent numerous incursions, so it was made much bigger to protect the core. As a result, the haddock population went from infinitesimal to off the charts. There had to be other factors involved, but the closure definitely played a part. While scallops are not the same as fin fish, closed areas accessed on a rotational basis are the reason the sea scallop fishery is as strong as it currently is. So I do not believe that closed areas have no benefit, and science and results seem to agree.

Bigger Is Better

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A number of years ago, I wrote about some research done separately by two scientists who essentially came to the same conclusion. One was David Conover, Ph.D., and the other Steve Berkley, Ph.D. Both found that older and larger predominantly female fish played an important role in the sustainability of any species, because they produce many more eggs per pound of body mass than smaller fish. Their eggs are more viable, and their larvae have a faster growth rate than those of young females. Steve Berkley showed that a 12-inch West Coast rockfish produced approximately 150,000 eggs, but a 28-inch fish produced 1.7 million eggs, a dramatic difference. Fish also have constant
low-level mortality over their lifespan and remain sexually reproductive.

Sound Science

David Conover conducted an ­experiment that split a school of ­tank-spawned Atlantic silversides into three tanks. One school had all the larger specimens removed for five generations. Another had all the smaller specimens removed. The third was ­randomly harvested. After five ­generations, they compared the fish that had the smaller size harvested to the fish that had the bigger specimens harvested. The smaller-size-harvested group had 54 percent higher growth efficiency. They had twofold higher fecundity, or egg production. Their eggs were 18 ­percent bigger. The larvae had a three times higher survival rate and a 20 percent higher growth rate.

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**A Boost for BOFs **

Both Conover and Berkley suggested two alternatives to help solve the problem: Institute MPAs or slot limits. But slot limits don’t work in mobile-gear ­commercial fisheries. In New England ­— and likely in other places — there are recreationally ­important species that are at ­all-time lows. We need to do something to protect what remains of the BOFs. Does it mean that recreational users will have to sacrifice something? Yes, likely we will. What should be put in place are gear-restricted areas that protect specific types of fish. What should not be put in place are marine reserves that simply say, “Keep out!” Same old, same old is not a viable alternative.z

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