Forage Questions

Regarding “Thinking Straight,” [Conservation, October 2017]:

A little more information on our paper on forage fish [“When does fishing forage species affect their predators?”]: Most importantly, we didn’t say that fishing forage fish doesn’t affect their predators, simply 1) It does not appear to always affect their predators and 2) When we looked at the data available for U.S. forage fish, we couldn’t find any relationship between predator population changes and forage fish abundance.

I realize it does seem counterintuitive that fishing a food supply won’t affect the predator, but that certainly seems to be the case in many instances. For instance, we have seen sea lions and pelicans in California increase greatly in the last 40 years at times when sardines were at both low and high abundance; the sea lions simply switch to other species when sardines are rare.

The aim of our paper was to convince the science and management community that each ecosystem needs to be examined individually, and that the general conclusions of the Lenfest report on forage fish were based on models that omitted some of the most important biology of forage fish and their predators.

You may be aware that the Lenfest program is run by the PEW Foundation, whose source of funds is the oil industry. PEW has spent hundreds of millions of dollars since the Exxon Valdez oil spill trying to divert public attention away from the impacts of oil on the ocean and putting recreational and commercial fishing as the target for public concern. Ray Hilborn School of Aquatic and Fishery Sciences, University of Washington, Seattle