Sea Sick: Setting Targets for Ocean Health

Is the health of the ocean good or bad, getting better or getting worse? The answer to this question depends on where it is now relative to where we want it to be. For each of 10 core goals, the Ocean Health Index has established targets, or points of reference that explain where we want ocean health to be. The targets make it possible to track progress toward recovery in less healthy places and celebrate successes in others. We have defined what is to be achieved for the core goals in the Ocean Health Index one at a time—so the targets are selfish. This design causes necessary trade-offs to emerge because what is good for achieving a target for one core goal might not be so good for another. The targets fall into two broad categories. One measures current status compared to the best possible value, where the best possible value either has deep theoretical underpinnings or is based on comparison to a regional maximum. The other type of target measures current ocean condition relative to where it has been during a previous time period. We illustrate these alternative types of targets with real-world examples related to fisheries, marine livelihoods, and water quality, and review how targets have been applied in the global assessment. Ocean health targets clarify exactly what a healthy ocean looks like, which is as essential to the development of a scientifically rigorous Ocean Health Index as it is for communicating about ocean health with policymakers and the public.