Thursday, November 15, 2012

It does take a rocket scientist

My perspective on fisheries is not typical. My fellow scientists are more likely to focus on scientific details and less on the implications of the science and its uncertainty for managers, fishing communities, and society. The involved public may see fisheries management as a messy political machine that answers to vested interests. I see it as a control system.

I mentioned Bruce Bollermann in my first blog, and it’s time to share the full story of our collaboration and his contribution to my views on fisheries management. Bruce and I are family—my brother Steve was married to his daughter, and they had three wonderful kids who are my teenage nephews. My brother is a couple of years older and had kids before I did. Being a family-oriented guy, I made a point of visiting Steve and his family in their Arizona home often. That meant that I regularly spent time with Bruce, who lived nearby. My politics are complicated but my sentiment runs liberal. In contrast, Bruce is a dyed-in-the-wool Republican. At the time, I was the senior scientist for a major ocean conservation group, while Bruce designed missile guidance systems for the military. Needless to say, conversations between us required navigating a minefield of potentially explosive topics.

Math saved us. From the beginnings of my PhD training, I have relied on mathematical models to describe ecosystems and their potential human influences. Bruce, too, relied heavily on math in designing systems to maximize the chance that a rocket hits its target. We slowly discovered our common interest in math and, over time, striking similarities in our mathematical techniques. Bruce was the first to float the idea of sitting down and comparing notes. I chalked his offer up to his semi-retired state, while I was working 60 to 80 hours a week trying to keep on top of all of the scientific needs of a growing organization. Looking back, though, it may simply have been generosity on his part since rockets tend to hit their targets, whereas fisheries, well, not so much. A key component of rocket science is called control theory, and it is the study of systems and how to best control them to achieve a desired result. What a perfect concept for fisheries management.

Despite the many demands on my time, I was able to convince two wonderfully supportive supervisors—Bob Irvin (now President of American Rivers) and Warner Chabot (who recently stepped down as CEO of California League of Conservation Voters)—to give me a week of time and a travel budget to head to Arizona and study rocket science, in the hopes it would shed some light on fisheries management.

The first day, Bruce went over the basic theory of rocket guidance systems. They have a well-defined target, a system that monitors progress toward the target, and thrusters that engage when the trajectory is off. These three components are all critical: a defined target, a monitoring system, and a mechanism to get back on track. The second day was my turn, and I had to admit to Bruce that fisheries are weak in all three components. Our targets are regularly chosen in an ad hoc manner, with political wrangling and concern over urgent problems often blocking any long-term planning. We invest in fisheries monitoring, but we evaluate progress for only the well-studied fish stocks (which are the exception, not the rule, as I pointed out last week) and even that typically takes place every one to five years. Bruce had a hard time with the concept that evaluations weren’t happening daily. However, the biggest failure in fisheries management is the lack of a responsive system to get them back on track. In contrast to Bruce’s sophisticated self-guiding missiles, fisheries managers usually shoot poorly aimed cannonballs.

Bruce and I looked at what might be possible with a fishery, even a poorly understood one, if managers made decisive cuts to fishing immediately when evidence suggested the stock was below a healthy target. The results were shocking: we could achieve highly productive catches with a low chance of fishery collapse. There was a hitch, though. Catches would be highly variable from one year to the next, with the possibility of frequent closures of the entire fishery. We published our work and I invite those of you with a keen interest in math, fisheries science, rocket science, or simply a cure for insomnia to look here.

As I dug deeper into the fisheries science literature, I found we were not the first to discover this potential for sustainable fisheries, nor the cost in terms of unpredictable catches. However, those who preceded us settled for fisheries management systems that traded off sustainability for more predictability in catches from one year to the next. Their initial recommendation in the late 1980s/early 1990s was to fish a constant fraction of the population each year, so that catches would be high when the stock was abundant and lower when abundance dropped. By the late 1990s, some scientists were encouraging managers to build in more sustainability by reducing catches more dramatically. However,

I don’t disagree with the need to make these trade-offs, nor with the more recent recommendations, which may be suitable for many fisheries. I do take issue, though, with scientists choosing the balance. Each fishery is different and deserves a management system designed with its ecological, economic, and social factors in mind. In the US, these considerations are even mentioned explicitly in our federal fisheries law under the definition of optimum yield. Yet, optimum yield is set at the same level for virtually every US fishery. The concept is applied especially poorly when we have little information about fish stocks, despite the existence of management alternatives that would work in these cases. At Bridge Environment, we believe we can do a better job of tailoring management systems so that they more closely resemble rocket guidance systems, with clearly defined targets, monitoring of progress, and decisive corrections when evidence suggests we are off-target. We especially appreciate the opportunity to work directly with fishing communities so that they can have a stronger voice in how to trade-off the size of catches, their variability, and their sustainability. In our experience, educated fishing communities will design and support high performance management systems that lead to healthier fisheries and marine ecosystems.

It turns out it does take a rocket scientist to manage a fishery. Thanks Bruce!

Warm wishes,

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