Environmental Change Complicates Issues Around Data Uncertainty

by Laurie Schreiber

A helicopter hovers close to the damaged bow of the Swedish liner Stockholm as the vessel limps into New York Harbor, July 27, 1956. The ship collided with the Andrea Doria two days earlier 45 miles southeast of Nantucket Island, MA. USCG photo.

PORTSMOUTH, N.H.—At its Jan. 29 meeting, the New England Fishery Management Council (NEFMC) considered a report from the National Aquarium regarding the sources of data uncertainty and the issue of managing fisheries when there is uncertainty.

In his presentation of the report, Steve Cadrin, with the University of Massachusetts/Dartmouth’s School for Marine Science and Technology, said that scientific sources of uncertainty include:

• Data – ‘measurement error’

• Model – ‘estimation error’

• Ecosystem – ‘process error’

• Management Sources – ‘implementation error’

He said it’s important to identify, communicate, and reduce uncertainty. On the latter, he said, potential strategies might include evaluating benefits and costs of additional research, alternative investments in data, or application of new technologies and methods for stock assessment.

When considering environmental change, he said, among the report’s recommendations are expanding fisheries oceanography research, integrating ecosystem science into stock assessments, and preparing for environmental shifts through education, control rules and reference points.

In addition, “Ecosystem status reports should be used to incorporate multi-species interactions and environmental conditions into assessments and management decisions,” Cadrin said.

Cadrin cited a case study used to consider environmental change in Alaska, where fishery managers were “explicitly proactive in the context of climate change,” he said. “They have more explicit processes and tools in place.”

NEMFC member Michael Sissenwine said that, while discussions of uncertainty tend to focus on how to reduce it, there’s little attention paid to the implications of uncertainty in terms of interactions that occur between multiple uncertain variables in the system.

Cadrin said the goal is to take a systems approach. For example, he said, management strategy evaluation is designed to consider uncertainties of data in both the commercial and recreational groundfisheries in the context of their interaction.

“At what point is accounting for uncertainty enough?” asked NEFMC member Eric Reid. That’s largely up to NEFMC, responded Cadrin.

“The answer to how much precaution is enough, I would think, is based on the performance of different levels of precaution,” he said. “If you have extreme precaution such that you have no fishery, that’s not performing well. If you have limited precaution and the fishery collapses, that’s not performing well either.”