Fishery Management: An Analysis of Fish Stock Assessments

Center for American Progress

Counting Fish 101

An Analysis of Fish Stock Assessments

George Lapointe, Linda Mercer, and Michael Conathan   

Science is integral to fishing operations. Without the ability to estimate how many fish exist in the ocean there’s no way to determine how many of them we can catch while allowing the remaining fish populations to stay viable. But fish live in a mostly invisible world beneath the ocean surface, they move around constantly, and they eat each other.

This creates a dynamic population structure that’s incredibly difficult to track, making fish virtually impossible to count. Thus, fisheries scientists—like political pollsters or other statisticians—must rely on imperfect data to make their predictions about the status and health of fish populations.

They take these data—some of which they collect, some of which come from fishermen—and plug them into scientific models which, in turn, create estimates of population health. Because the entire population of a given species is frequently divided into subpopulations known as “stocks,” these estimates are called “stock assessments,” and they form the backbone of modern fishery management in the United States.

These assessments provide an estimate of the current state of a fish population and, in some cases, forecast future trends. This tells us whether fishery management goals are
being met and indicates the type of conditions to which the fishery will have to adapt in the near future. In an ideal world, scientists would have the resources to provide managers with updated stock assessments for each species every year, but their expense and complexity mean they can only be updated periodically.

Regardless of how frequently they can be updated, strong, science-based stock assessments are the key to future sustainability, not just of the fish but also of the fishing industry. Fishing is an inherently unstable business, yet strong, accurate science can give fishermen a better understanding of whether their resource will remain healthy, and if it does, how many fish they will be allowed to catch. This in turn allows fishermen to make informed business decisions and stabilizes coastal economies.

Read the full report here.

Sea Level’s Rise Focus of Summit

Projections of dramatic change draw group to UCSD to strategize about vulnerabilities of affected areas

LA JOLLA — Climate researchers, social scientists and policy experts from across the Pacific Rim convened at UC San Diego last week to get ahead of seas projected to rise so dramatically that they could create some of the most visible effects of global warming.

Representatives from about 20 leading research universities and nonprofit groups in South Korea, Russia, Indonesia and elsewhere met to prepare for potentially catastrophic effects on 200 million people and trillions of dollars of coastal assets.

Sea levels off most of California are expected to rise about 3 feet by 2100, according to recent projections by the National Research Council. Higher seas create challenges for port cities from San Diego to Singapore, including the potential for dramatically increased damage to coastal roads, homes and beaches — especially during storms.

“All future development has to be assessed in regards to future rises in sea level,” Steffen Lehmann, professor of sustainable design at the University of South Australia, said during the conference. “Reducing the vulnerabilities of urban (areas) is the big topic, the big task ahead of us now.”

Potential responses include managing a retreat from eroding bluffs and reshaping coastal areas to buffer development from higher water levels. “The missing link (is) between the science and those guys in planning offices and architecture firms and city municipal offices,” Lehmann said.

David Woodruff, director of the University of California San Diego’s Sustainability Solutions Institute, organized the workshop to address that problem with cross-disciplinary discussions that move toward international action.

“We are trying to affect societal change,” he said. “The sooner we start scoping options, the less expensive it will be to save current infrastructure.”

The workshop was sponsored by the Association of Pacific Rim Universities, a consortium of 42 leading research institutions. Participants drafted a report about rising sea levels for top university leaders so they can make the topic a priority with national-level leaders around the Pacific Rim.

“I really think universities can play a key role,” said UC San Diego’s Charles Kennel. “They are right at the pivot point between connecting knowledge to action. … One of the places they need to transfer their knowledge to is adaptation to climate change.”

A warming climate causes sea levels to rise primarily by heating the oceans — which causes the water to expand — and by melting land ice, which drains water to the ocean. Sea levels at any given spot depend on a complex interaction of factors, such as ocean and atmospheric circulation patterns and tectonic plate movements.

Global sea level has risen about 7 inches during the 20th century, the National Research Council said.

While sea-level-rise projections aren’t a sure thing, they are widely accepted by mainstream scientists. Skeptics see it as a waste of money to plan for problems that may not materialize for decades, or may be more modest than predicted.

Read more on the Union-Tribune San Diego.

Sardines stuffed with cream cheese & herbs

Stock up on your Omega-3 with sardines. Sardines are cheap and they are worth their weight in gold. If there are people that don’t really like sardines, you can stuff them with cream cheese and herbs. They taste differently and I am sure they will be a hit.