Landmark Report Outlines How to Find Out How Many Fish Are in the Ocean (and are being caught by fishermen) | Oceana

Landmark Report Outlines How to Find Out How Many Fish Are in the Ocean (and are being caught by fishermen)

Press Release Date: October 6, 2009

Location: Washington


Anna Baxter | email:
Anna Baxter

A landmark scientific study released today by Oceana provides guidelines for one of the greatest unsolved problems in fisheries management – how to gather data on how many fish are caught by fishermen.

The study was authored by premier fishery assessment scientists Elizabeth Babcock and Ellen Pikitch, formerly of the Wildlife Conservation Society, and as of October 2003, with the Pew Institute for Ocean Science at the University of Miami, along with Charlotte Gray Hudson, a marine wildlife scientist at Oceana.  The study is an innovative, new “how to” guide for fishery managers in designing and running effective fishery observer programs.

Fishery observers are independent scientists who work alongside fishermen at sea.  Observers collect important information about what is actually caught, as compared to landings data, which only records what is brought to port.  Observers are critical in addressing bycatch or what fishermen often call “dirty-fishing.”  Dirty-fishing includes the catch and subsequent destruction of unwanted fish and marine life – fish that are the wrong type, size, sex, or quality as well as marine mammals, sea turtles, and seabirds.

A critical issue for managers is determining how to produce reliable and accurate results from observer programs in many different fisheries, each with unique characteristics.

“This study is for fishery managers who have to work in the real world, where it’s not always possible to have an observer on every fishing boat,” said Babcock.  “We tried to demonstrate how to get the most useful and reliable information from an observer program.”

The study says at the onset of an observer program, managers should use whatever data is available, and should refine and improve coverage levels as new observer data is collected.  If bycatch estimates are too high, then fishermen may be unnecessarily restrained; but if they are too low, it can lead to management measures that do not protect the fishery – meaning less fish in the ocean and even less money in fishermen’s pockets.

“Fishery observer programs must be both precise and accurate to ensure that their results provide meaningful information for fisheries management,” said Pikitch.  “Our results show that when a species of concern is rare, at least 50 percent observer coverage may be required.  For more common species, 20 percent may be adequate.”

There are approximately 300 U.S. federally-managed fisheries, yet only about 20 observer programs — most of which need to be expanded to provide more complete information based on the studies findings.  Because of this limited information, it is likely that the amount of marine life killed from dirty-fishing is different from what managers think.

“Management decisions based on faulty assumptions are bad for the fish and the fishermen,” said Hudson.  “On-board observers are the best way to get the information we need to stop the destruction to our oceans and ensure that our fisheries are sustainable.”

The release of the report comes as Congress weighs proposals to increase funding for observer programs.  In its Commerce, Justice, State (CJS) FY04 appropriations bill, the Senate is proposing an approximately 66 percent increase in total funding for observer programs from $13.8 million to $22.9 million.  The House is proposing an increase in funding to $17.0 million.  The budget bills are expected to be finalized in this month.

Oceana is a non-profit international advocacy organization dedicated to restoring and protecting the world’s oceans through policy advocacy, science, law and public education. Founded in 2001, Oceana’s constituency includes members and activists from more than 150 countries and territories who are committed to saving the world’s marine environment.  Oceana, headquartered in Washington, D.C., has additional offices in key U.S. coastal areas; a South American office in Santiago, Chile; and a European office in Madrid, Spain.  For more information, please visit or call (202) 833-3900.