Sardine Numbers Remain Low, 2016 Fishing Remains Closed

Stock assessment finds sardine biomass below cut-off level for directed fishing this year

Last weekend scientists and managers at the Pacific Fishery Management Council weighed the results of a new stock assessment of sardine populations off the West Coast.  This new assessment, which was approved and adopted as best available science for management of sardine in the 2016-2017 fishing year, shows that sardine numbers remain low, and remain below the cut-off level where directed fishing for the species could again be allowed.

Kelp Sardines PacificBased on this information, and the management framework in place for this stock, the Council voted to keep fishing for sardine closed for the second year in a row.  As occurred last year, the Council voted to allow for small amounts of sardine taken (up to a total of 8,000 metric tons) as live bait harvest, Tribal harvest, incidental catch in other fisheries (such as mackerel and anchovy), and for scientific research studies.

Directed commercial fishing for Pacific sardine is not allowed because the assessment estimated the spawning biomass to be approximately 106,000 metric tons. This is below the cut-off level of 150,000 metric tons, the lowest level at which directed fishing is allowed. This cut-off threshold, included in the Coastal Pelagic Species fishery management plan, is set three times greater than the level at which sardines are considered overfished. This approach limits fishing as the stock declines to help maintain a stable core population of sardines that can jump-start a new cycle of population growth.

The stock biomass is the size of the adult sardine population of reproductive age (a year old and older) as measured by offshore surveys conducted by NOAA Fisheries in the last year. The estimate does not include very young fish that are not yet part of the spawning population.

There are some indications of stronger sardine reproduction in the last year that could eventually lead to improvements in West Coast sardine numbers, scientists said. For example, surveys in 2015 counted increased numbers of small sardines off central California and similarly found young sardines along the Oregon-California Coast that would not be included in overall stock biomass estimates, and as such, would not be represented in the stock assessment. That indicates that sardines spawned along the West Coast last year and, if the young fish survive, they could add to the adult population in coming years.

Although sardines usually spawn off central California in the spring, last year they apparently spawned farther north, off Oregon. That suggests that sardine spawning may have shifted, perhaps in response to unusual ocean conditions such as “the blob,” an expanse of warm water that dominated West Coast waters through much of 2014 and 2015, and the El Nino climate pattern now affecting the region.

“The normal timing and distribution of sardine spawning has shifted dramatically as a result of warm water conditions the last three years and we did not catch them in their usual spawning areas at their regular time,” said Dale Sweetnam, deputy director of the Fisheries Resources Division at NOAA Fisheries’ Southwest Fisheries Science Center, which leads sardine surveys and stock assessments on the West Coast.

Sardines are known for their wide-ranging “boom-and-bust” population cycles around the world. They have been in decline off the West Coast since a series of cool years from 2010 to 2014 reduced the survival of eggs and very young fish so that few survived to join the adult spawning population. The question now is whether recent warmer conditions may boost the survival of the large numbers of young fish so that more survive long enough to join the adult population.

Two annual stock assessment surveys, one currently underway this spring and another one planned for this summer will help to answer that question.

“We have had a few years of very unusual conditions on the West Coast, and we’re still learning what that means for sardines and many other species,” Sweetnam said. “Our best sources of information are the surveys that tell where the fish are and how well they’re surviving. Preliminary results this spring suggest that we did have good recruitment last year; however, the magnitude and extent of that recruitment will have to wait until we have completed the surveys.”

Pacific sardine science and management
Frequently Asked Questions
April 2016

Q: What is the status of the Pacific sardine population off the West Coast?
A: According to the 2016 stock assessmentThe previous link is a link to Non-Federal government web site. Click to review NOAA Fisheries Disclaimer, Pacific sardine are not overfished and are not subject to overfishing*. Directed fishing has not been allowed since April 2015. However, the stock assessment estimates that the population continues to be below the level at which directed fishing is allowed (150,000 metric tons), and managers are therefore keeping the fishery closed. 

*A population is overfished when removals by the fishery impair ability of the population to replace itself. Overfishing occurs when fish are caught faster than the population can replace them. 

Q: Why is the Pacific sardine population low?
A: The population size varies naturally and is influenced by environmental changes, which can lead to large fluctuations (boom-bust cycles) in abundance and catch. Environmental changes affect reproductive output and survival of young (“recruitment”). Recruitment has been low in recent years, and this appears to have driven the population down. The combined effects of predation, harvest and climate are difficult to disentangle, however. 

Q: What has the Pacific Fishery Management Council done to respond to the decrease in Pacific sardine biomass? What is the Council planning to do? 
A: The fishery closed in 2015 because the population was below the minimum precautionary level set by managers. Directed commercial fishing for Pacific sardine will not be allowed for the 2016 fishing season because the 2016 assessment estimated the spawning biomass continues to be below the lowest level at which directed fishing is allowed.

Regular stock assessments ensure that NMFS uses the best available science for setting sustainable annual harvest limits, regardless of fluctuation in biomass due to fishing pressure, environment or a combination of factors. 

An approximately 33 percent decline in biomass from 2012 to 2013 resulted in an approximately 60 percent decrease in the harvest guideline from 2012 to 2013; and a subsequent 44 percent decline in biomass from 2013 to 2014 resulted in a 66 percent decrease in the harvest guideline (HG) from 2013 to 2014. HGs are set well below the annual overfishing limits (OFL) recommended by the Council and the Council’s Science and Statistical Committee.  

Q: Is the Pacific sardine stock experiencing overfishing?
A: No. Under the Coastal Pelagic Plan, overfishing occurs if catch exceeds the overfishing limit. For the US this was 13,227 mt for the 2015-16 fishing year and catch as of April 2016 has been 100 mt. Annual catch has never exceeded the harvest guidelines, therefore catch has never exceeded the OFL and overfishing has not occurred. In addition, the directed fishery has been closed since April 2015. 

Q: Why did the Pacific sardine biomass increase from 2015 to 2016? 
A: The Pacific sardine spawning biomass in the 2015 assessment was 96,688 mt (as of July 2015) and in the 2016 assessment was 106,137 mt (as of July 2016). These are not statistically significant differences. The increase in biomass is corroborated by data from NOAA Fisheries surveys, which indicated the recruitment improved in 2015 and suggested that biomass was higher than that calculated in the 2015 assessment. 

Q: What is the cut-off? Is the cut-off a “set aside” for predators? 
A: Cutoff is the lowest level of estimated biomass at which fishing is allowed. The purpose of the cutoff is to protect the stock when biomass is low (CPS FMP). The cutoff provides a buffer of spawning stock that is protected from fishing and available for use in rebuilding if a stock becomes overfished. If the cutoff is greater than zero, then the harvest rate declines as biomass declines. By the time biomass falls as low as the cutoff, the harvest rate is reduced to zero. 

Cutoff is not a set aside for predators. A set-aside for predators is accounted for in the natural mortality (M) rate assumed for the stock. Although the Cutoff is not an explicit set-aside for predators, forage considerations were a primary part of the decision framework used for choosing the current HG control rule as a whole which includes the cutoff.

California Sea Lion Status Questions & Answers
Frequently Asked Questions
April 2016

Q: Is it the lack of sardines that has caused large numbers of sea lion pups to wash up dead or in poor condition?
A: The recent strandings (the washing up dead or in poor condition) of California sea lion pups are attributed to unusually warm ocean conditions.  

For the past three years, significant numbers of California sea lion pups have been stranding in central and southern California. We (the SWFSC, NWFSC, AFSC and WCRO) are working on a holistic explanation of the pup deaths, its relation to forage fish availability, the ecosystem and other ocean conditions on the west coast. 

Since the early 1970s the California sea lion population has grown from 50,000 to over 300,000, an unprecedented amount. But in the past few years, ocean conditions have been especially unfavorable for juvenile sea lion survival, which may lead to population declines in the near future. 
NOAA scientists suspect that the huge swath of unusually warm water – due to the “blob” and El Niño – found along the California coast that is not rich in sea lion prey has forced nursing females to travel farther, deeper and to stay away from their pups longer in search of food. The unusually warm water has apparently shifted the distribution of prey, particularly that of shallow schooling species, making it harder for lactating females to find enough food to support the nutritional needs of their pups. As a result, young pups dependent on their mother’s milk to survive are not gaining weight and growing as they normally would at this time of year. Hungry pups are being abandoned. Those strong enough may strike out from the rookeries on their own but many do not survive and instead wash up on shore dead or emaciated.  If they are rescued, they can be rehabilitated, however, poor feeding conditions for California sea lions will likely continue while warm ocean conditions persist.

Q: What is an unusual mortality event (UME) and why did NOAA declare one along the U.S. west coast?
A: An unusual mortality event (UME) is defined under the Marine Mammal Protection Act as a stranding event that is unexpected, involves a significant die-off of any marine mammal population, and demands immediate response. There are seven criteria used to determine whether a mortality event is "unusual." If the Working Group on Marine Mammal Unusual Mortality Events, a group of marine mammal health experts, determines that an event meets one or more of the criteria, then an UME is declared. The California sea lion UME was declared under three criteria: a marked increase in the magnitude or a marked change in the nature of morbidity, mortality, or strandings when compared with prior records; a temporal change in morbidity, mortality, or strandings is occurring; and affected animals exhibit similar or unusual pathological findings, behavior patterns, clinical signs, or general physical condition (e.g., blubber thickness).

Q: What is NOAA doing to save dying sea lions?
A: NOAA Fisheries does our best working with our stranding network partners to respond to sick marine animals. 

• As part of our Marine Mammal Health and Stranding Response Program, NOAA Fisheries works closely with partner organizations to respond to stranded marine mammals. Trained specialists respond to reports of stranded animals to assess their condition and determine the appropriate response. They take into consideration elements such as how safe it is for the response team and the public, the health status of the animal, if there is space at an animal hospital where they can be rehabilitated, and if there are other healthy animals close by that should not be disturbed. 
• If members of the public come across a stranded sea lion or fur seal, we urge them to maintain a safe distance, keep pets away, and to report the animal to a local stranding network member. The network can deploy authorized personnel who are trained in handling sick, injured, or dead animals. To report a dead, injured or stranded marine mammal please call: 1-866-767-6114. Remember, do not interact with wild marine mammals and view marine mammals in a manner that does not harass the animals. 

Q: What is the status of the sea lion population? Are there too many sea lions? 
A: The US California sea lion population increased from approximately 50,000– to over 300,000 individuals from 1975 to 2014. Ultimately, the increasing sea lion population is expected to fluctuate around some as yet unknown, and probably varying, maximum that the environment can sustain with a reduced rate at which it grows. 

Q: How can managers balance the demands of human fisheries with the needs of marine predators? 
A: Both the abundance and the type of forage species (sardine, anchovies and other coastal pelagic species) has shifted in the California Current and is of concern for sea lions, fishermen and the public interested in these species. NOAA Fisheries works closely with the Pacific Fisheries Management Council and stakeholders to balance these interests under changing ocean conditions. 

Q: Are we going to continue to see emaciated and dying sea lions?
A: Scientists observed another year of low pup weights during their annual survey on the San Miguel Island rookery off California in 2016, where sea lions and fur seals breed and rear their young. In fact, pup weights were among the lowest recorded for the two species in more than forty years. 

California sea lions, other top predators (e.g., cetaceans and birds) and the commercial fishing industry will likely all be affected by the decadal changes in forage productivity. In the near term, we expect more years of malnourished and starving sea lion pups, but because we cannot forecast fluctuations in forage, we cannot predict whether low abundance of these forage fish will last or how long. Given the likelihood that the California sea lion population is approaching carrying capacity, reduced pup survival or production of pups may be a long-term consequence of a rebuilt sea lion population during the current period of reduced abundance of high-quality forage.