The Collapse of Central Valley Salmon
The latest federal government data on 2007′s salmon run on the Sacramento River point to an "unprecedented collapse" in the fishery considered for years to be one of the most healthy on the West Coast.
If the data is verified in upcoming meetings of the Pacific Fishery Management Council (PFMC), commercial and recreational salmon fishing in California and Oregon ocean waters and recreational salmon fishing in Central Valley rivers could be closed or severely restricted in 2008. This alarming news couldn’t come at a worse time, since recreational and commercial fishermen are already reeling from draconian restrictions on rockfish, lingcod and other groundfish in California.
"The magnitude of the low abundance, should it be confirmed in verification efforts now underway, is such that the opening of all marine and freshwater fisheries impacting this important salmon stock will be questioned in the upcoming Council process to set 2008 ocean salmon seasons," according to an internal memo of the Pacific Fishery Management Council (PFMC) by Donald O. McIsaac, Ph. D, Executive Director. "This is particularly disconcerting in that this stock has consistently been the healthy ‘work horse’ target stock for salmon fisheries off California and most of Oregon."
According to McIssac, the Salmon Technical Team (STT) met last week at the Council office to tabulate total counts of West Coast salmon stocks, including spawning escapements and catches. Two areas of bad news emerged relative to the 2008 abundance level for this important stock:
o The adult spawning escapement for this stock in 2007 failed to meet the goal for the first time in 15 years and only the second time in 35 years. This unexpected result indicates the carry-over of older fish in the ocean that might contribute to 2008 abundance will probably also be weak.
The adult salmon escapement was only 90,000 fish, down from about 275,000 a year earlier. The Sacramento River returns were 88,000 fish, while the San Joaquin River returns were only 2,000 adult chinooks.
o The count of jacks in the Central Valley fall Chinook return this past fall, which are used to predict adult abundance in 2008, was–by far–a record low: an order of magnitude less than average and less than a fourth of the previous record low.
The return of Central Valley fall Chinook jacks in 2007 was about 2,000 compared to a long term average of about 40,000 and the previous record low of 10,000.
"It is also noteworthy that this low jack return is outside the range of the current tool used to predict abundance for a given year, calling into question the reliability of its utility for use in 2008," he said. "Obviously, two consecutive jack returns at the lowest (2007) and second lowest (2006) levels on record represent a severe situation."
McIssac said there "were informed discussions" last week about whether a reasonable forecast of abundance in 2008 could rise to the point of achieving the spawning escapement goal in the absence of any commercial or recreational salmon fishing anywhere on the West Coast that Central Valley fall Chinook are typically found in significant abundance.
"It is important to note that the current information needs to be verified and validated, and that it is three or four weeks before the documents are finalized that the Council will use in its deliberations," explained McIssac. "However, it is typical that the estimates at this stage do not vary much from the finalized values."
McIssac also noted the potential collateral effects of this "unprecedented salmon fishery" situation to groundfish recreational fisheries, open access commercial groundfish and albacore fisheries, other fisheries, and research planning.
"What is not clear at this time is the reason for the apparent collapse, although it is notable that both hatchery and naturally produced fish have been negatively affected," he concluded.
The federal and state governments will probably try to blame "ocean conditions" for the unprecedented collapse of salmon fisheries. Others will cite the increase of sea lion and harbor seal populations along the coast, the invasion of the highly predatory Humboldt squid, the change in forage fish populations off the coast and other factors.
Although ocean conditions and other factors are important to consider, I believe that unprecedented water exports out of the California Delta in recent years play a major role in the collapse of Sacramento and San Joaquin chinook populations.
The salmon are apparently the victims of the Delta food chain crash that has resulted in record low numbers of delta smelt, longfin smelt, juvenile striped bass and threadfin shad in the California Delta since 2005. During 2005, an unprecedented 6.4 million-acre feet of water was exported out of the Delta by the state and federal governments.
The salmon that returned in 2007 as "jacks and jills" two year old fish – would have migrated downriver in 2005 at the same time that record water exports were taking place. Those smolts may have starved from lack of food as they migrated through the Delta, never making it to the ocean. Or they may have ended up stranded in South Delta sloughs and channels, sucked in by powerful reverse flows caused by export pumping, if not destroyed in the pumps themselves.
Another factor that probably played a role was the fact that the pen release program of the Fishery Foundation of California was not in place in 2004 and 2005. Through this program, the salmon smolts are released into brackish water after being acclimated for 1 to 2 hours. This program cuts down greatly on smolt mortality.
The absence of the pens apparently contributed to increased salmon mortality when the DFG released them into San Pablo Bay those years. Fortunately, the program will be in place this year when the salmon are released into the bay.
"This news about the salmon population collapse is not surprising considering the decline of the California Delta food chain caused by increased export pumping by the state and federal governments," said Dick Pool, owner of Pro Troll products and coordinator of Water4Fish.org. "We need the state and federal governments to solve this problem."
After receiving word of the low abundance of Central Valley salmon forecasted in 2008, Jim Martin, West Coast Coast Regional Director of the Recreational Fishing Alliance, said he hoped that the PFMC was able to keep a recreational chinook season open because of the minimal impact of recreational anglers on the overall salmon population.
"If the Council closes salmon fishing completely, it will put more pressure on the rockfish population," said Martin.
For more information, contact the PFMC, 7700 NE Ambassador Place, Suite 101, Portland, Oregon 97220-1384, Phone: (503) 820-2280, Fax: (503) 820-2299, Web: www.pcouncil.org
DAN BACHER can be reached at: email@example.com