|
|
||||||
|
Sancutary Program Accomplishments Open Ocean & Deep Water Systems Endangered & Threatened Species Harvested Species
|
|
Events occurring in 1998, however, can be placed in a longer term framework to provide an indication of the current status of marine fish and invertebrate resources. This report provides a brief summary of the status of fish stocks in the Monterey Bay National Marine Sanctuary from 1980-95 as described in Fishery Resources of the Monterey Bay National Marine Sanctuary, and discusses the main events affecting fishery resources in 1998. About 200 species are typically caught in commercial and recreational fisheries in the Sanctuary. From 1980-95, reported commercial catches increased or were stable for about 17 percent of the species frequently harvested in this region. Reported catches declined for about 10 percent of the frequently harvested species. Catches and thus population status of other species are either unknown or highly variable. Invertebrate species most frequently harvested commercially include spot prawn, pink shrimp, Dungeness crab, rock crab, and market squid. Harvests of spot prawn, Dungeness crab, and rock crab all increased from 1980-95. Pink shrimp populations declined throughout much of the late 1980s, then increased from 1994-95. The market squid population was low during the El Niño years of 1983-84, reached record levels in 1994-97, then declined dramatically with the onset of the 1997-98 El Niño. Shark and ray species are no longer harvested in large numbers in the Sanctuary. There is, however, evidence to suggest that the population sizes of some shark and ray species are lower now than they were before 1980. Chinook, or "king," salmon is the most common anadromous species caught in the Sanctuary. Reported catches of Chinook salmon have been high in the last few years. Scientific stock assessments indicate that the fall run Chinook salmon of the Sacramento River is in good shape, but that populations of Coho salmon and winter and spring run Chinook salmon are severely depressed. Steelhead populations are extremely depressed in this area, due primarily to degraded stream habitats. Abundances of most pelagic species are greatly determined by large scale environmental phenomena. Northern anchovy and Pacific sardine are the predominant nearshore pelagic fishes caught in the Sanctuary. Anchovy spawning biomass in Central California declined after 1985, but experienced a substantial increase from 1994-95. Pacific sardine populations are also increasing rapidly throughout their range after nearly disappearing from the region in the 1950s. In 1998 the commercial fishers reported seeing large numbers of small (young) sardines. The population of Pacific albacore, another common pelagic species, is currently thought to be stable or increasing. Biological and fishery data indicate that lingcod may be overfished in much of their range. In 1998 the Pacific Fishery Manage-ment Council's stock assessments indicate that lingcod abundance is at approximately 9 percent of the estimated unfished biomass off Washington and Oregon. This caused the Council to reduce recreational harvest quotas and begin to develop a rebuilding plan. Similarly, sablefish have been heavily fished in California waters. Sablefish catches in the Sanctuary have been decreasing since 1980, but data from recent surveys suggest the population may be increasing. Pacific hake are very abundant seasonally in the Sanctuary as they migrate from Mexican to Canadian waters. Pacific hake catches were high off Central California throughout most of the 1980s.
Dave Danbom, Moss
Landing
Rockfishes are the most diverse group of fishes living in Sanctuary waters. Sufficient data are available to show stable or increasing trends in abundance for some rockfishes such as bank, chilipepper, shortbelly, widow, and splitnose. Other rockfish species such as bocaccio, yellowtail, canary, and Pacific ocean perch have exhibited decreasing trends in abundance along the U.S. West Coast. Many of these depleted rockfishes are deep water species that are slow growing, long lived, or have experienced high exploitation rates. Fishery managers are concerned about the capability of some of these species to recover from high harvest rates and in 1998 continued to reduce harvest guidelines for many rockfish species.
Dr. Mal Stock,
Several species of fishes that occur in kelp forests and other nearshore habitats are under high fishing pressure from both commercial and sport anglers. In the late 1980s, fishers started transporting fish alive to restaurants. This type of fishery became very lucrative and fishing pressure increased rapidly. Landings of live fish in Central California increased from 15,000 pounds in 1989 to 536,000 pounds in 1997. The result of this interest in live fish for the restaurant market was an increase in the harvest of immature fish, a major resource conservation problem. There are already signs that some nearshore species such as cabezon are rapidly becoming depleted from the high fishing pressure. New legislation was enacted in 1998 that placed size limits on many nearshore fishes and directed the California Department of Fish and Game to develop specific fishery management plans for nearshore species. California AB 1241 also provided a fundamental change in the way that fisheries management will take place in California in the future. It requires the state to manage fisheries proactively for sustainability, instead of for short-term profits. It also transfers much of the responsibility for management from the legislature to the Fish and Game Commission.
Dave Crabbe
Surfperches represent a diverse group of nearshore fishes in the Sanctuary waters. Historical catch data show that surfperch populations have declined, due to a number of factors including environmental variation, lower production caused by smaller fish, habitat degradation, and increased fishing pressure. In contrast, landing data and stock assessments suggest that populations of most species of flatfishes are robust and could withstand increased levels of harvest. In addition to population changes brought about by fishing activities, broad scale environmental changes affected marine resources in 1998. Most notably, marine habitats and species were affected by strong El Niño conditions. The marine environment experienced high inflows of fresh water, sediments, and nutrients from winter floods. Northwest winds were lighter than normal, causing poor upwelling conditions. These poor upwelling conditions have been shown to be detrimental to survival of juveniles of many local species, such as rockfishes. Water temperatures were also 2 - 4° C above normal, probably causing poor survival of many species, but notably juvenile market squid. The strong water mass flow from the south and corresponding warm water brought many species to this area that are not typically seen here. Species that occurred in the Sanctuary in 1998 that are typically not seen in large numbers included albacore, sheephead, marlin, swordfish, pelagic red crabs, and jumbo squid.
Duncan McLean,
The Sanctuary's enabling legislation excludes fishery management from the purview of its regulations. The Sanctuary charge is to protect resources, however, and there is much the Sanctuary program can do to improve fishery management. More scientific information is needed to optimize catches from fisheries without depleting fish populations. Information is needed not only on population abundance and critical life history stages, but on the interactions between species, the effect of harvest activities on marine habitats, and the effect of environmental change on marine fishes. Increased research is also needed to evaluate the design and effectiveness of current methodologies, as well as to develop new, more efficient management strategies. Richard M. Starr
|
||||
The
ocean environment in the Monterey Bay region is
very dynamic and greatly influences resident fish
populations. This variability makes estimating the
"health" of marine fish and invertebrate
populations difficult using one year as a basis for
discussion. Additionally, most of the information
used to estimate the size of fish populations is
derived from commercial and recreational fisheries.
Catch rates are used as an index of abundance, and
long term data sets are usually needed to model or
estimate trends in the abundance of fish stocks
effectively. Even with these long term data sets,
it is often difficult to determine if changes in
fish populations are the result of societal
activities, such as fishing or coastal development,
or due to environmental changes.