Are Southeast halibut and salmon populations heading for a crash?

Posted: Wednesday, January 28, 2009

There are serious issues with Southeast Alaska's marine ecosystem that have been steadily getting worse. For instance, the 2007-2008 winter king troll fishery just closed after harvesting only 45 percent of the 45,000 fish quota. Furthermore, both the halibut and summer chinook commercial quotas have been dramatically reduced by 48 percent. Sport and guided sport fishing have been severely restricted as well.

Are we experiencing problems similar to those plaguing Mexico, California, Oregon, Washington and parts of British Columbia? In these cases, biologists are naming starvation as a contributing factor.

A recent study on Southeast Alaska halibut has concluded that today's fish weigh 50 percent less than the same age class weighed in 1988. A check of records indicates that the average size and abundance of chinook are getting smaller as well. The same holds true for silver salmon in most areas in the last two years. All of these species rely on herring as a key component in the food web as prey.

Coastal communities throughout Southeast Alaska with local and traditional knowledge of herring claim that historic stock levels have significantly declined due to factors that include over-harvesting, predation and climate changes.

Perhaps the factor presently having the greatest impact in this area may be attributed to predation. It appears that protected marine mammals are increasingly having a much larger impact on herring stocks than anyone envisioned. Although a sea lion can eat 80 pounds daily, according to data from the Web site, an adult humpback whale consumes about two and a half tons of herring, needlefish, krill and plankton each day.

The population of humpbacks has increased dramatically since implementation of the Marine Mammal Protection Act in 1972. Using calculations based on National Marine Fisheries Service data, there were probably fewer than 100 humpbacks in Southeast Alaska when the act became law. By 1995, the population of Southeast Alaska humpbacks from Frederick Sound north was 404. Within five years it had jumped to 961 in that area. Today there are calculated to be at least 1,650 of these whales eating over 4,000 tons of feed per day. This does not include whales observed in the 180 miles from Frederick Sound south to the Canadian border which have never been surveyed. It's important to realize that humpbacks not only eat herring, they also consume the plankton and krill that herring rely on to survive.

When the Alaska Department of Fish & Game began conducting herring sac roe fisheries in 1976, there were seven major spawning areas in Southeast Alaska, along with countless smaller ones. Today, there are only two major spawns left. One is near Craig. The other is in Sitka Sound. Without regard for these serious issues, this spring ADF&G conducted an all-time record-high herring sac roe harvest of over 28,460,000 pounds of this critical species from Sitka Sound. With possible disaster looming over some of Alaska's most important fisheries, is this conservative management? In the opinion of most locals, it is better to leave what remains of Southeast Alaska's herring in the water, put an end to the killing of herring for their eggs, and begin researching ways to restore the once-great masses of herring taken from the waters of Southeast Alaska.

At present, ADF&G and the Board of Fisheries that governs it are putting at risk many critical components of Southeast Alaska's economy, including commercial fishing, sport and guided sport fishing, and a large portion of the tourism industry, not to mention the reputation of the state of Alaska.

• Andy Rauwolf is a Ketchikan resident, builder, sport fisherman, power troller, hand troller and halibut long-liner. He spent the last 28 years closely monitoring and documenting the decline of Southeast Alaska's herring stocks and writes on behalf of the Ketchikan Herring Action Group.

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