An updated report on growing sea otter impacts on commercial fisheries in Southeast Alaska says the overall value loss to sea cucumber, geoduck, red sea urchin and Dungeness crab fisheries since 1995 totaled $28.3 million.
State fisheries biologists and a private research firm estimate that the sea cucumber fishery lost 3.2 million pounds with an estimated ex-vessel value of $5.3 million and wholesale value of $8.95 million from 1996 through 2011.
The geoduck fishery lost 530,500 pounds with an estimated ex-vessel value of $3.2 million and estimated wholesale value of $4.2 million from 2005-2011, and the red sea urchin fishery lost 3.1 million pounds worth an estimated $1 million ex-vessel and nearly $4 million wholesale, from 1995 through 2005. The Dungeness crab fishery meanwhile lost 2.7 million pounds, with an estimated ex-vessel value of $3.3 million and wholesale value of $5.3 million from 2000 thru 2010.
The McDowell Group, in Juneau, prepared the report for the Southeast Alaska Regional Dive Fisheries Association.
The McDowell Group found that commercial harvest closures have resulted in measurable economic impacts on the seafood sector and on communities in Southeast Alaska, including lost employment, wages, tax revenue and related economic activity.
The association contracted with McDowell group to quantify and explain these impacts in 2005. Since that report was completed, otter populations have continued to grow, further impacting dive fisheries and crab fisheries.
The updated report, completed in late 2011, uses current Alaska Department of Fish and Game data and sea otter research to update the impacts of sea otter predation on Southeast Alaska fisheries and communities, the report said.
Researchers at McDowell Group found that the wholesale value loss due to the impact of sea otter predation on the red sea cucumber, geoduck clam, red sea urchin, and Dungeness crab fisheries was $22.4 million from 1995 through 2011, with the multiplier impact on the regional economy being an additional $5.8 million.
Dive fisheries and Dungeness crab fisheries in Southeast Alaska had a first wholesale value of $25 million in 2010, employing roughly 625 fishermen as well as processing workers and tender operators, the report said. The secondary economic activity resulting from these fisheries is estimated to be $6.5 million or equivalent to 59 full-time jobs.
Since 1995, the report said, the sea cucumber fishery has lost an estimated 3.3 million pounds worth $9 million in wholesale value and $5.3 million in ex-vessel terms, due to sea otter predation. Sea otter impacts were found to be particularly harmful in 2011, with a loss of an estimated 235,000 pounds worth $2.23 million in wholesale value. The average commercial diver harvesting sea cucumbers in 2011 lost an estimated $7,000 in ex-vessel value. Since 1992, ADF&G has closed seven areas either specifically due to sea otter predation or presumably due to sea otter predation, the report said.
Since 2005, the geoduck clam fishery has lost an estimated 530,500 pounds worth $4.2 million in wholesale terms, and $3.2 million ex-vessel terms, due to sea otter predation. Impacts were particularly costly in 2011, with an estimated 140,900 pounds with a wholesale value of $2 million lost due to predation. The average commercial diver harvesting geoducks in 2011 lost an estimated $30,00 in ex-vessel value, the report said.
While no geoduck harvest areas have been closed due to sea otter predation, ADF&G has identified 27 fishery areas with evidence of sea otter predation, the report said. About 70 percent of the commercial geoduck harvest comes from these 27 fishery areas, where surveys note large craters and shell fragments left over from sea otter predation.
Red sea urchin harvests have declined substantially since 2006. Industry sources indicate only one or two divers harvested urchins in 2011, with only one active buyer. Sea otter predation impacts since 2005 have not been compiled, due to the decline of the fishery and the confidential nature of most data associated with it. The decline of the red sea urchin fishery in recent years is market related and not due to sea otter predation, the report notes. Prior to 2006, an estimated 3.1 million pounds of sea urchin harvest with a wholesale value of $4 million was lost due to sea otter predation.
Despite a declining commercial fishery, sea otter predation continues to negatively impact stocks. The 2011/12 red sea urchin guideline harvest level is 3.28 million pounds, down 40 percent from the 2008/2009 guideline harvest level of 5.44 million pounds.
Sea otters also eat Dungeness crab.
The three-year average harvest from districts with significant sea otter presence was 975,000 pounds less in 2008 through 2010 than from 2000-2002, a decline of 38 percent, the report said.
In comparison, districts with less sea otter presence saw average harvests increase 151,000 pounds for the same two periods, an increase of 7 percent.
Researchers said the Southeast Alaska Dungeness crab fishery has lost an estimated 2.7 million pounds of commercial harvest worth $3.3 million in ex-vessel value and $5.3 million in wholesale value since 2000.
Sea otters were removed from their natural range in Southeast Alaska due to intense pressure from fur traders in the 18th and 19th centuries. Prior to that time, sea otter populations in the entire North Pacific Rim, from Japan to Alaska to Baja California, ranged from 200,000 to 300,000 animals.
In 1911, the North Pacific Fur Seal Convention was passed to protect sea otter populations in the United States, Russia and Japan from further intensive exploitation.
From 1965 to 1969, a total of 402 sea otters from the Aleutian Islands and Prince William Sound were reintroduced to Southeast Alaska. That population remained low until 1987, when it began a period of rapid growth.
The most recent population survey, conducted in 2002 and 2003, estimated the Southeast sea otter population at 8,949 animals. The report also quotes results of aerial surveys done in 2010 that estimate Southeast Alaska sea otter populations to be growing at a rate of 12 percent annually.
The complete report is online at http://www.scribd.com/doc/74857876/MCDOWELL-GROUP-2011-Sea-Otter-Impacts-Report.