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State of Sanctuary Resources

This section provides summaries of the condition and trends within four resource areas: water, habitat, living resources and maritime archaeological resources. For each, sanctuary staff and selected outside experts considered a series of questions about each resource area. The set of questions is derived from the National Marine Sanctuary System’s mission, and a system-wide monitoring framework (National Marine Sanctuary Program 2004) developed to ensure the timely flow of data and information to those responsible for managing and protecting resources in the ocean and coastal zone, and to those that use, depend on, and study the ecosystems encompassed by the sanctuaries. The questions are meant to set the limits of judgments so that responses can be confined to certain reporting categories that will later be compared among all sanctuary sites and combined. The Appendix (Rating Scheme for System-Wide Monitoring Questions) clarifies the set of questions and presents statements that were used to judge the status and assign a corresponding color code on a scale from “good” to “poor.” These statements are customized for each question. In addition, the following options are available for all questions: “N/A” the question does not apply; and “undetermined” resource status is undetermined. In addition, symbols are used to indicate trends: “ conditions appear to be improving; “▬” conditions do not appear to be changing; “ conditions appear to be declining; and “?the trend is undetermined.

This section of the report provides answers to the set of questions. Answers are supported by specific examples of data, investigations, monitoring and observations, and the basis for judgment is provided in the text and summarized in the table for each resource area. Where published or additional information exists, the reader is provided with appropriate references and Web links.

Some of the questions refer to the term "ecosystem integrity."  When responding to these questions, experts and sanctuary staff judged an ecosystem's integrity by the relative wholeness of ecosystem structure, function, and associated complexity, and the spatial and temporal variability inherent in these characteristics, as determined by its natural evolutionary history.  Ecosystem integrity is reflected in the system s "ability to generate and maintain adaptive biotic elements through natural evolutionary processes" (Angermeier and Karr 1994).  It also implies that the natural fluctuations of a system's native characteristics, including abiotic drivers, biotic composition, symbiotic relationships, and functional processes are not substantively altered and are either likely to persist or be regained following natural disturbance.

Water

Figure 30. March 12, 2000 MODIS true color image capturing the San Francisco-Oakland metropolitan area, Point Reyes and the offshore location of Cordell Bank sanctuary. Notice the influence of San Francisco Bay outflow on the offshore environment. Image created by Pam van der Leeden, CBNMS.
Figure 30. March 12, 2000 MODIS true color image capturing the San Francisco-Oakland metropolitan area, Point Reyes and the offshore location of Cordell Bank sanctuary. Notice the influence of San Francisco Bay outflow on the offshore environment. Click here for a larger image.(Image created by Pam van der Leeden, CBNMS)

Cordell Bank is far enough offshore to be expected to be relatively free of direct impacts associated with terrestrial inputs. The eastern edge of the sanctuary is located six miles (10 km) from shore, and is adjacent to western Marin and Sonoma counties, which are sparsely populated and rural in character. Due to depth, resuspension of bottom sediments is not thought to substantially affect water quality (Figure 30). A report investigating the current state of knowledge of water quality in West Coast sanctuaries concluded that the Cordell Bank sanctuary is the least likely of the five sanctuaries to be impacted by sources of water pollution due to its offshore location and open ocean conditions (Meyers 2005).

The following information summarizes an assessment by experts in the field and sanctuary staff of the status and trends pertaining to water quality and its effects on the environment in Cordell Bank National Marine Sanctuary:

1. Are specific or multiple stressors, including changing oceanographic and atmospheric conditions, affecting water quality and how are they changing?

Oceanic water quality off northern California is generally good, except in areas adjacent to population centers, such as San Francisco Bay. The location of Cordell Bank sanctuary, 40 miles (64 km) to the northwest of the San Francisco Bay, generally buffers the sanctuary from any direct outflow effects. The prevailing winds and currents flow from the north, so water flow out of the Bay is driven to the south, away from Cordell Bank for most of the year. This is not the case in the winter, when storm conditions are characterized by heavy rainfall, strong southerly winds, and a coastal current that flows northward. As an example, in January 2006 impacts from severe flooding of coastal counties in northern California, caused by heavy rainfall, were observed at Cordell Bank during a winter monitoring cruise (Cordell Bank sanctuary, unpubl. data). Debris such as large logs, dock pilings, floats, bottles, balloons, plastic sheets, and bags littered the surface waters over Cordell Bank, likely originating from San Francisco Bay. This event was an indicator that extended El Niño conditions with heavy rains could affect water quality at Cordell Bank sanctuary as water and debris from San Francisco Bay intrudes into the sanctuary. The plume from the Russian River (located 13 miles, or 21 km north of the sanctuary's northeast corner) may enter the sanctuary in winter and spring, but typically this flow is inshore of the bank. An analysis of temperature, chlorophyll concentrations, and turbidity within the sanctuary between 1997 and 2004 indicated a strong influence on these parameters from El Niño events, seasonal changes in upwelling, and seasonal changes in the strength of the California Current. However, there were no indications of reduced productivity or decreased water quality trends over time (Stumpf et al. 2005). This could change, however, if weather patterns shift.

Anomalous atmospheric conditions in 2005 and 2006 delayed the onset and intensity of coastal upwelling along the northern California coast (Peterson et al. 2006). If these atmospheric conditions become a persistent feature in this area, then the potential would exist for negative impacts caused by the decoupling of life history patterns and early season oceanographic productivity. In addition, negative ecosystem impacts could result if oceanographic conditions such as temperature and pH continue to be altered by climate change. Stressors on water quality from changing oceanographic and atmospheric conditions are currently not producing long-term negative effects. For this reason, the rating for this question is "good." A trend is "undetermined" due to a paucity of data.

2. What is the eutrophic condition of sanctuary waters and how is it changing?

There is no evidence of eutrophication within the Cordell Bank sanctuary or the surrounding waters. For this reason, this question is rated "good" and "not changing." Chlorophyll levels spanning seven years (1997-2004) were summarized and chlorophyll in the sanctuary never approached values that would indicate eutrophication (Stumpf et al. 2005). Monthly estimates of chlorophyll-a in recent years (2004-present) demonstrate similar patterns (Cordell Bank sanctuary, unpubl. data). Levels of chlorophyll-a concentrations and the absence of harmful algal blooms, as measured from samples taken within the sanctuary (California Department of Health Services, monthly reports), lead sanctuary scientists to believe that eutrophication is not a problem within Cordell Bank sanctuary, and conditions appear stable.

3. Do sanctuary waters pose risks to human health and how are they changing?

Monthly water sampling is conducted to identify early warning signs of harmful algal blooms. Photo: Michael Carver, CBNMS
Figure 31. Monthly water sampling is conducted to identify early warning signs of harmful algal blooms. (Photo: Michael Carver, CBNMS)

Water samples are taken from the Cordell Bank sanctuary during monthly monitoring cruises for the California Department of Health Services. The purpose of the sampling is to identify early warning signs of harmful algal blooms, focusing on the dinoflagellate Alexandrium catenella (which causes paralytic shellfish poisoning) and the diatom Pseudonitzschia spp (domoic acid carriers) (Figure 31). To date, there have been no indications of elevated levels of either species (California Department of Health Services, monthly reports). Although these data are insufficient to identify the effects of specific stressors, there are currently no data to suggest that water quality is compromised and could pose a risk to human health. For this reason, this question is rated "good" with a "stable" trend.

4. What are the levels of human activities that may influence water quality and how are they changing?

The level of human activities that influence water quality in the sanctuary is considered to be minimal, so this question is rated "good/fair" and the trend is "undetermined" although threats to water quality including large vessel spills and discharges from large commercial ships exist. Based on previous releases and known levels of vessel traffic, these pressures are considered to have the potential to degrade water quality, and may preclude full function of living resource assemblages and habitats, should they occur. Yet, while vessel numbers transiting the sanctuary do not appear to be increasing (1999-2005, United States Coast Guard, Automatic Identification System, unpubl. data), it is unknown what the levels of discharge are from these vessels and how this has changed through time.

Water Quality Status and Trends
table
# Status Rating Basis For Judgement Description of Findings
1. Stressors
?
Offshore location may limit impacts, but data are sparse. Conditions do not appear to have the potential to negatively affect living resources or habitat quality.
2. Eutrophic Condition
-
Absence of harmful algal blooms and low chlorophyll levels do not indicate eutrophication. Conditions do not appear to have the potential to negatively affect living resources or habitat quality.
3. Human Health
-
Offshore location and oceanic conditions may limit impacts; no known risks identified during monthly monitoring. Conditions do not appear to have the potential to negatively affect human health.
4. Human Activities
?
Minimal human activities, but uncertainty of the levels of vessel discharges. Some potentially harmful activities exist, but they do not appear to have had a negative effect on water quality.

Habitat

Habitat loss and fragmentation are perhaps the most serious threats confronting all species of wildlife today. Many of the activities and conditions that indirectly affect marine life are first experienced as an alteration or disturbance to their habitat.

The following information provides an assessment by sanctuary staff of the status and trends pertaining to the current state of benthic habitats in Cordell Bank National Marine Sanctuary:

5. What is the abundance and distribution of major habitat types and how are they changing?

The Cordell Bank sanctuary’s 529 square miles (1370 km2) of benthic habitat can be partitioned into three types: 1) the continental shelf covers 313 square miles (810 km2) and is primarily mud bottom ranging from 230-656 feet (70-200 m) deep, 2) the continental slope covers 190 square miles (492 km2) and is primarily mud bottom with some rock outcrops and ranges between 656 feet (200 m) at the shelf break down to 6955 feet (2120 m) at the western boundary of the sanctuary, 3) Cordell Bank is roughly 4.5 miles wide by 9.5 miles long (7.2 x 15.2 km) covering an area of approximately 26 square miles (68 km2). The rocky bank emerges from the soft sediments of the continental shelf, with the upper pinnacles reaching to within 115 feet (35 m) of the ocean’s surface. Shelf depths at the base of the bank are between 300 and 400 feet (91-122 m).

Figure 32. Cordell Bank provides deep water refugia of boulder habitats for overfished species such as Boccacio. Photo: Dave Murfin, NOAA.
Figure 32. Cordell Bank provides deep water refugia of boulder habitats for overfished species such as Boccacio. (Photo: Southwest Fisheries Science Center, NOAA Fisheries).
The Cordell Bank sanctuary has a diversity of habitats that include high relief rock pinnacles, flat rock, boulders (Figure 32), cobble, sand, and mud. High resolution backscatter and bathymetry data were recently collected on Cordell Bank and the surrounding soft bottom areas by California State University of Monterey Bay and habitat characteristics such as slope, rugosity, depth, and substrate type are being used to quantitatively describe the physical habitats that make up the bank. (For more information on mapping Cordell Bank, see the Seafloor Mapping Lab at California State University, Monterey Bay Web site.

The abundance and distribution of major habitat types is rated fair,  reflecting impacts from past long line and bottom trawling activities. Historically, trawl intensity was concentrated in several locations of the sanctuary, specifically in the region of the shelf break as well as within deeper regions of the sanctuary on the continental slope (Final Environmental Impact Statement 2008; Fig. 3-4). Recently, a variety of fishery management measures, including Rockfish Conservation Areas and Essential Fish Habitat Conservation Areas (see Figure 23, in pressures section), have been implemented that limit the extent of trawling activity and use of bottom contact fishing gear in the sanctuary. Currently, 86% of the Cordell Bank sanctuary is closed to some type of bottom tending fishing gear (see Figure 23, in pressures section). The net effect of these measures may be an improvement in the condition of habitats due to some recovery of seafloor habitats in the areas that were previously trawled or fished with other bottom contact gear. Nevertheless, a directed study to determine habitat differences in open and closed areas and recovery rates of benthic habitats relieved of fishing pressure has yet to be conducted. For this reason, the trend is "undetermined."

6. What is the condition of biologically structured habitats and how is it changing?

Figure 33. Biologically structured habitats on Cordell Bank include hydrocorals, sponges, and anemones. Photo: Cordell Expeditions
Figure 33. Biologically structured habitats on Cordell Bank include hydrocorals, sponges, and anemones. (Photo: Cordell Expeditions).
Biologically-structured habitats, identified as habitat created by invertebrate communities on the upper bank (including hydrocorals and sponges) (Figure 33) and sea whip (Halipteris sp.) fields on the soft mud of the continental shelf appear, for the most part, to be healthy (Cordell Bank sanctuary, unpubl. data). These biologically structured habitats have, however, been impacted in the past by long lines, gill nets and bottom trawls (Cordell Bank sanctuary, unpubl. data). For this reason, this question is rated "fair." Activities that currently have the greatest potential impact on the sanctuary's benthic habitats are the use of bottom-tending fishing gears, the deposition of lost fishing gear and other marine debris, the introduction of non-native species, and the construction and placement of cables and pipelines.

Figure 34. 	Location of derelict fishing gear (black dots) in the Cordell Bank area as detected during submersible monitoring surveys of the bank community.  Gear locations are overlaid on high resolution bathymetry, which was generated from multibeam echosounder data (source: Seafloor Mapping Laboratory at California State University Monterey Bay). Contour lines are drawn every 50m and illustrate the location of the bank on the continental shelf in close proximity to the shelf break and steep continental slope. Image created by Lisa Etherington, CBNMS.
Figure 34. Location of derelict fishing gear (black dots) in the Cordell Bank area as detected during submersible monitoring surveys of the bank community. Gear locations are overlaid on high resolution bathymetry, which was generated from multibeam echosounder data (source: Seafloor Mapping Laboratory at California State University Monterey Bay). Contour lines are drawn every 50m and illustrate the location of the bank on the continental shelf in close proximity to the shelf break and steep continental slope. Click here for a larger image. (Image created by Lisa Etherington, CBNMS.).
From 2001-2005, Cordell Bank sanctuary conducted demersal submersible surveys on and around the bank. During these surveys, fishing gear was consistently observed on the bottom (Figure 34). In 2002, derelict gear was observed entangled on the seafloor on 18 of the 20 transects (90%) conducted over rocky habitat. The most common gear types observed were long-lines and occasional gill nets. Most gear is entangled among boulders or on high relief rock. Many of the high relief areas are covered with hydrocorals and other encrusting invertebrates and derelict gear has been documented entangled on these sensitive species.

As some areas in the sanctuary are now off limits to the use of bottom contact gear and bottom trawling (see Figure 23, in pressures section), condition of biologically structured habitats should improve; however, there is insufficient data to determine a trend. Further, due to the slow growth of some habitat-forming organisms, such as cold water corals, recovery from past damage could be slow. Furthermore, it is not known how scouring from storm events and subsequent larval settlement affect the condition of the biologically structured habitat. It is also unclear how a long-term warming trend in the ocean and changes in pH would affect the condition of the lush invertebrate community carpeting the upper reaches of the bank.

7. What are the contaminant concentrations in sanctuary habitats and how are they changing?

Contaminant concentrations in sanctuary benthic habitats are poorly understood. There have been very few sediment contaminant samples collected on the shelf and slope within Cordell Bank sanctuary. As a result, the assessment of contaminant concentrations is "undetermined" with an 'undetermined" trend. Preliminary analysis of several samples indicates low levels of Dichloro-Diphenyl-Trichloroethane (DDT), polychlorinated biphenyls (PCBs), and polycyclic aromatic hydrocarbons (PAHs) (I. Hartwell, NOAA's National Status and Trends Program, unpubl. data) (Figure 35). These data indicate that accumulation of DDT, PAHs, and PCBs may be occurring in the depths of Bodega Canyon (a feature 10 km north of Cordell Bank sanctuary), a pattern that holds true for other canyons as well, as evidenced by elevated concentrations in fine grained sediments in deeper areas in Pioneer and Lucia Canyons to the south of CBNMS (Hartwell 2007, 2008). Persistent contaminants also collect in fine grained sediments at the head and down the length of Monterey, Soquel, Ascension, and Año Nuevo canyons (Figure 35). The nature of the compounds will cause them to accumulate in the food chain at some level. Further work is needed to understand contaminant concentrations, transport pathways, and changes in contaminant concentrations over time.

Figure 35. PCB, DDT, and PAH concentrations off the coast of California. Bodega canyon to the north of Cordell Bank sanctuary shows higher concentrations of these contaminants compared with many of the sampling locations in the region. Source: Hartwell, NOAA NST, unpubl. data.
Figure 35. DDT, PAH, and PCB concentrations off the coast of California. Bodega canyon to the north of Cordell Bank sanctuary shows higher concentrations of these contaminants compared with many of the sampling locations in the region. Click here for a larger image. (Source: Hartwell, NOAA NST, unpubl. data.)

8. What are the levels of human activities that may influence habitat quality and how are they changing?

In the past, bottom contact fishing gear within the Cordell Bank sanctuary affected habitat quality. However, gear restrictions and area closures associated with the Rockfish Conservation Areas (RCAs) and Essential Fish Habitat (EFH) have reduced human activity in the sanctuary, decreasing habitat impacts (see Figure 23, in pressures section). For this reason, this question is rated fair  and improving.  It is not clear, however, if or when closures associated with the RCAs and EFH may be lifted, an eventuality that could reverse current trends in human activity levels.

Habitat Status and Trends
table
# Status Rating Basis For Judgement Description of Findings
5. Abundance/Distribution
?
Prior fishing gear impacts, some activities now prohibited; sparse data. Selected habitat loss or alteration may inhibit the development of assemblages, and may cause measurable but not severe declines in living resources or water quality.
6. Structure
?
Prior fishing gear impacts, some activities now prohibited; sparse data. Selected habitat loss or alteration may inhibit the development of assemblages, and may cause measurable but not severe declines in living resources or water quality.
7. Contaminants
?
Sparse data available. N/A
8. Human Activities
Prior fishing impacts; some activities now prohibited. Selected activities have resulted in measurable habitat impacts, but evidence suggests effects are localized, not widespread.

Living Resrouces

The current state of living resources in the sanctuary is a snapshot in an evolving relationship between biological populations, physical processes and outside pressures. These pressures can be natural or human induced, and in many cases where populations fall to critically low levels, it is a combination of both. Many populations of fishes, marine mammals and seabirds are still recovering from historic declines caused by pollution, over-harvesting, destruction of habitat, and recruitment failure. Several species, like gray whales, brown pelicans and elephant seals, have experienced considerable population increases after exploitation or other human activities reduced their numbers dramatically. Other populations, like leatherback sea turtles, Chinook and coho salmon, and some species of rockfish, are at all time lows. In 2008, the commercial and recreational salmon season off the coast of California and Oregon was closed for the first time ever due to reduced population levels. And in recent years, jumbo squid populations have expanded to Cordell Bank from the south and have persisted in the area; this top-level predator has the potential to have significant impacts on the biodiversity and community composition within the sanctuary.

9. What is the status of biodiversity and how is it changing?

Species have probably not been lost from the marine ecosystem within the Cordell Bank sanctuary in recent history and it is likely that species richness has not declined. However, changes in the abundance of several key groups suggest that relative abundance of different species (species evenness) has changed and community composition has been altered. Changes in oceanic conditions in recent years (Peterson et al. 2006, Goericke et al. 2007) have likely altered productivity within the sanctuary, with consequent changes in abundance and distribution of many taxa, including krill, marine mammals, and seabirds. Further, depletion of rockfish stocks due to overharvesting, as well as poor recruitment, has likely affected both species composition and reduced rockfish biomass on Cordell Bank; however, recent stock assessments suggest that many populations of overfished species are increasing (Pacific Fishery Management Council 2006). In addition, the range expansion and recent addition of jumbo squid to the marine ecosystem in this area could have a large impact on community structure. In combination, these natural and human-induced alterations have diminished, to some extent, ecosystem integrity in both benthic and pelagic systems. For these reasons, the status of biodiversity in the sanctuary is rated as fair  and improving. 

The conditions of the following groups were used to assess the overall status of biodiversity:

  • Benthic invertebrates: Overall biodiversity of benthic invertebrates on soft and hard substrates on the continental shelf appears healthy, based on limited observations (Cordell Bank sanctuary, unpubl. data). Photographs of the invertebrates of the reef top of Cordell Bank taken by Cordell Expeditions in the late 1970s (Schmieder 1991) reveal an assemblage very similar to that observed by sanctuary staff in 2005 (Cordell Bank sanctuary, unpubl. data), suggesting that current biodiversity of this group is stable. The condition of slope invertebrates is virtually unknown.

  • Pelagic invertebrates: Annual fluctuations in pelagic invertebrates are related to oceanic conditions; a warming trend in coastal oceans could affect population structure and species composition. The recent persistent residence of the jumbo squid within the region of the sanctuary (Zeidberg and Robison 2007) suggests the possibility that the marine ecosystem has been or will be altered by the addition of a top level predator, resulting in shifts in community composition.

  • Fishes: Overharvest of some rockfish populations (i.e. yelloweye, canary, and cowcod), combined with poor recruitment, has severely impacted their populations along the west coast (Ralston 2002) and has resulted in the closure of some groundfish fisheries in an attempt to rebuild depleted populations (Figure 36).
    Figure 36.Relative depletion of overfished rockfish species that are managed by the PFMC. Data is based on the most recent set of stock assessments. Source: S. Ralston, unpublished data.
    Figure 36. Relative depletion of overfished rockfish species that are managed by the PFMC. Data is based on the most recent set of stock assessments. Click here for a larger image. (Source: S. Ralston, unpublished data).
    There is also some indication that the general removal of large predators (e.g., yelloweye rockfish) can alter species composition, allowing populations of smaller fishes (e.g., the pygmy rockfish (Sebastes wilsoni) and squarespot rockfish (S. hopkinsi)) to expand (Baskett et al. 2006). This process may help explain data from recent submersible observations on Cordell Bank, in which pygmy rockfish were the most abundant rockfish observed on Cordell Bank (Anderson et al. 2007, in review.). Closures associated with Rockfish Conservation Areas and Essential Fish Habitat Conservation Areas have been established; these protected areas will locally reduce fishing pressure and help rebuild depleted rockfish populations (see Figure 23, in pressures section). Population metrics from recent stock assessments indicate an increase in population abundance over the last five years for many overfished species, while populations of other species considered overfished appear to be stable (Pacific Fishery Management Council 2006). Lingcod are a top predator and their population has been declared rebuilt after consecutive years of good recruitment (Pacific Fishery Management Council 2006).
    Figure 37. Pelagic juvenile rockfish abundance from midwater trawl surveys conducted from Bodega Bay to Carmel, CA. Note that the y-axis is a logarithmic scale. Source: S. Ralston, unpublished data.
    Figure 37. Pelagic juvenile rockfish abundance from midwater trawl surveys conducted from Bodega Bay to Carmel, CA. Note that the y-axis is a logarithmic scale. (Source: S. Ralston, unpublished data).
    Nevertheless, pelagic juvenile rockfish surveys in 2005 within the northern California region indicated an all time low in catch (for a 23 year data set) (Figure 37) and an apparent shift in distribution of fish to the north and the south of the central California region (Peterson et al. 2006; S. Ralston, NOAA's Southwest Fisheries Science Center, unpubl. data). A combination of instream pressures such as water diversion and degraded spawning habitat and poor ocean conditions have taken a toll on populations of Chinook and coho salmon. Poor spawning escapement and record low numbers in the ocean elicited an unprecedented closure of the commercial and recreational fall run Chinook salmon fishery in 2008.

  • Seabirds: Locally breeding seabird populations within central and northern California have generally suffered long term declines (Ainley and Hyrenbach 2007). For example, the mean density of Ashy Storm-Petrels, Rhinoceros Auklets (Cerorhinca monocerata) and Western Gulls (Larus occidentalis) from at-sea surveys in northern California have declined significantly over the time period of 1985-1994 compared to 1997-2006 (Ainley and Hyrenbach 2007). Some locally breeding species (e.g., Cassin's Auklets) have experienced reduced reproductive success in recent years due to poor feeding conditions in the coastal ocean (Sydeman et al. 2006). Abundance of non-resident species, such as Sooty Shearwaters (Puffinus griseus) and Black-footed Albatrosses (Phoebastria nigripes), have also declined within the waters of northern California (Ainley and Hyrenbach 2007), potentially due to population declines resulting from human impacts in remote locations.

  • Marine mammals: Stock assessments suggest that many of the populations of marine mammals that use sanctuary habitats are stable or increasing. For example, there is evidence suggesting an increasing population for the eastern North Pacific humpback whale stock (Carretta et al. 2007). Nevertheless, the distribution and use of sanctuary habitats by some marine mammals (e.g., blue whale) in recent years (i.e., 2005-06) appears to have been altered (Peterson et al. 2006) due to a decrease in the overall abundance of krill in the area (Peterson et al. 2006, Sydeman et al. 2006, Jahncke et al. 2008).

10. What is the status of environmentally sustainable fishing and how is it changing?

The status and trend ratings for this question are based on the available scientific knowledge (e.g., published studies, unpublished data, and expert opinion) of targeted and non-targeted living resources that are directly and indirectly affected by fishing. The rating reflects a more historical view of the potential effects of fishing activity on biological community development, function, and ecosystem integrity, over the last two to three decades. The rating does not serve as an assessment of the status of current fisheries management practices in the region.  However, the determination of an increasing trend for this question does reflect recent changes in fisheries management practices and their positive effects on living resources in the sanctuary.

In the early 2000's, seven species of rockfish - widow (Sebastes entomelas), yelloweye (S. ruberrimus), canary (S. pinniger), darkblotched (S. crameri), bocaccio (S. paucispinis), cowcod (S. levis), and Pacific ocean perch (S. alutus) - were formally declared overfished throughout their range by the NOAA Fisheries (Figure 36); all but cowcod, Pacific ocean perch, and darkblotched rockfish are relatively common within the sanctuary (Anderson et al. in review). In addition, long lines, gillnets, and bottom trawls have negatively impacted seafloor habitats and benthic organisms in the sanctuary. For these reasons, this question is rated “fair.” However, the trend is considered to be “improving” because the management strategies used by NOAA Fisheries and the Pacific Fisheries Management Council (PFMC) have become much more restrictive since the Sustainable Fisheries Act was passed in 1998. Prohibitions associated with the Rockfish Conservation Area closures and regulations implemented in 2006 by Essential Fish Habitat (EFH) Conservation Areas are encouraging sustainable fishing practices by prohibiting the use of destructive gear types on selected benthic habitats (see Figure 23, in pressures section).

NOAA Fisheries conducts an annual survey to estimate the distribution and abundance of pelagic juvenile rockfish in the immediate region of the sanctuary (Figure 37). Results show that during the late 1980s, catches averaged 10-100 fish/trawl, but during the 1990s, there was a general decline in abundance, falling to 0.2 fish/trawl in 1998. Catches later increased to ~10 fish/trawl from 2001-04, but dropped abruptly to their lowest value in the time series in 2005 (0.1 fish/trawl). Since then, catches have increased slightly, but still remain low (0.4 fish/trawl in 2007). Trends in abundance of exploited and unexploited species are very similar, implying that variation in the environment is largely responsible for these trends (S. Ralston, NOAA's Southwest Fisheries Science Center, unpubl. data).

Management regimes for commercial fishing are currently more risk adverse than in prior decades, and some measures are proving successful in allowing over-fished stocks to recover. Many of the species are responding positively to management changes and are showing clear evidence of recovery based on stock assessments. For depleted rockfish species with stock assessment data, all are showing increasing trends in spawning biomass over the past 10 years. Contributing to these recoveries are gear changes to reduce by-catch, limits on the number of permitted vessels in the fishery, and several closures and restricted areas (e.g., Essential Fish Habitat bottom trawl closures and the Rockfish Conservation Area). Fishing for rockfish is prohibited within the Rockfish Conservation Areas but recovery of over fished species is expected to take some time due to slow maturity rates for these species. Lingcod was previously declared overfished but is now recovered; harvest restrictions proved successful, as the rapid growth and maturity of this species resulted in more rapid population increases than the over-fished rockfish species. The prohibition of both bottom trawling and use of bottom contact gear in Essential Fish Habitat (EFH) Conservation Areas, which were designated in 2006 in some offshore areas, is expected to increase habitat protection (Figure 23). In response to dwindling groundfish populations and in an effort to protect groundfish habitat, a series of prohibitions, quotas, and gear restrictions have made it less profitable to trawl and the number of active trawlers has declined.

11. What is the status of non-indigenous species and how is it changing?

A number of non-native species are present in the marine environment near Cordell Bank sanctuary, but none are known to currently exist in the sanctuary; however, there has not been a comprehensive inventory of species within the sanctuary. For this reason, this question is rated "undetermined" for both its status and trend. There is some concern regarding an invasive tunicate, Didemnum sp. that has been observed in nearby coastal areas and has covered large areas of Georges' Bank on the east coast (Bullard et al. 2007). The invasive tunicate is similar to a native Didemnum species and sampling will be necessary to determine which species is present on Cordell Bank.

12. What is the status of key species and how is it changing?

Changes in oceanic conditions in recent years have altered productivity within the sanctuary, with changes in abundance and distribution of many taxa, including indicator species such as krill, blue whales and Cassin's Auklet. Further, depletion of rockfish stocks due to overharvesting, and poor recruitment is suspected to have caused an overall decline in the rockfish biomass and altered species composition on Cordell Bank; however, stock assessments suggest that many populations of overfished species are increasing. Several of the indicator species appear to have been negatively impacted by the combination of natural and human-induced forces. Substantial or persistent declines, however, are not expected for most of these species and several of the indicator species that feed within the sanctuary exhibit healthy populations that are increasing. For these reasons, the status of key species is rated fair  and "improving."

Key species were selected for several groups of animals inhabiting Cordell Bank National Marine Sanctuary. In some cases, local and migratory representatives were selected from one group to capture population changes that may be associated with pressures on different temporal and spatial scales. The following provides a summary for selected indicator species or groups:

  • Reef-top Invertebrates: The upper reef areas of Cordell Bank shallower than 60 meters are covered with a rich and diverse assemblage of benthic invertebrates. Sponges, strawberry anemones, hydrocorals, and tunicates encrust rock surfaces, while more mobile sea stars, sea urchins and crabs move over the surface of this reef. Photographs taken by Cordell Expeditions in the late 1970s (Schmieder 1991) reveal a biological assemblage very similar to that observed by sanctuary staff in 2005 (Cordell Bank sanctuary, unpubl. data).

  • Krill: Krill are keystone species and large changes in population size are related to changing oceanic conditions. Reduced primary productivity in 2005 (Jahncke et al. 2008), which was associated with anomalous atmospheric conditions that delayed upwelling, limited krill population growth and impacted the condition of higher trophic levels dependent on krill (Sydeman et al. 2006, Jahncke et al. 2008).

  • Rockfish: Rockfish are the dominant group of fishes on Cordell Bank, and status varies by species. In the early 2000's, seven species of rockfish - widow (Sebastes entomelas), yelloweye (S. ruberrimus), canary (S. pinniger), darkblotched (S. crameri), bocaccio (S. paucispinis), cowcod (S. levis), and Pacific ocean perch (S. alutus) - were formally declared overfished throughout their range by the NOAA Fisheries; all but cowcod, Pacific ocean perch, and darkblotched rockfish are relatively common within the sanctuary (Anderson et al. in review) (Figure 38).
    Figure 38. Canary rockfish are seen in deeper reef areas of the sanctuary.  Photo: Tara Anderson, CBNMS
    Figure 38. Canary rockfish are seen in deeper reef areas of the sanctuary. (Photo: Tara Anderson, CBNMS).
    Population metrics from recent stock assessments indicate an increase in abundance over the last five years for many overfished species, while populations of other species considered overfished appear to be stable (Pacific Fishery Management Council 2006; Figure 36). Nevertheless, pelagic juvenile rockfish surveys in 2005 within the central and northern California region (Carmel to Bodega Bay) indicated an all time low in catch (for a 23 year data set) (Figure 37) and an apparent shift in distribution of fish both to the north and the south of the central California region (Peterson et al. 2006). There is also some indication that the general removal of large predators (e.g., yelloweye rockfish) can alter species composition, allowing populations of smaller fishes such as pygmy and squarespot rockfish to increase (Baskett et al. 2006). In recent submersible surveys of demersal fishes, pygmy rockfish were the most abundant rockfish observed (Anderson et al. 2007, in review).

  • Sea Turtles: Between 1982 and 1996, the world population of leatherback sea turtles declined drastically, from 115,000 to 34,500 adult females (Spotila et al. 2000) and the population status is currently endangered. Much of the mortality occurs when eggs are harvested from beaches and adults are taken as bycatch in high seas fisheries. The northern California region, including the Cordell Bank sanctuary, is an important foraging area for adult leatherbacks in late summer and fall (Benson et al. 2007a). The occurrence of leatherbacks within the sanctuary is likely tied to changes in oceanic conditions and the availability of jellyfish (Benson et al. 2007a).

  • Cassin's Auklet: Cassin's Auklets (Ptychoramphus aleuticus) nest on the Farallon Islands and use local sanctuary waters to feed (Jahncke et al. 2008, PRBO Conservation Science, unpubl. data, Cordell Bank sanctuary, unpubl. data), foraging primarily on krill. Abundance patterns of Cassin's Auklets from at-sea surveys in the central and northern California region (Monterey to Bodega Bay) indicate decreasing trends in abundance between the time periods of 1985-1994 and 1997-2006 (Ainley and Hyrenbach 2007). Further, complete reproductive failure of Cassin's Auklets on the Farallon Islands in 2005 and 2006 related to anomalous oceanic conditions and poor early season productivity (Figure 39, Sydeman et al. 2006, Peterson et al. 2006, Goericke et al. 2007, PRBO Conservation Science, unpubl. data) may have long term impacts; however, recent data suggest the population is rebounding (Figure 39; PRBO unpubl. data).

    Figure 39. Breeding success (a) and diet (b) of Cassin s Auklets on Southeast Farallon Island, CA from 1970s-2007. Cassin s Auklets breeding on the Farallon Islands feed in the surrounding waters including Cordell Bank sanctuary, where they are one of the most abundant seabirds. Note the dramatic change in breeding success and diet in 2005 and 2006, a time period when upwelling was delayed and weak, causing changes in the abundance of krill, the auklets  primary prey.  Source: PRBO Conservation Science, unpubl. data.

    Figure 39. Breeding success (a) and diet (b) of Cassin's Auklets on Southeast Farallon Island, CA from 1970s-2007. Cassin's Auklets breeding on the Farallon Islands feed in the surrounding waters including Cordell Bank sanctuary, where they are one of the most abundant seabirds. Note the dramatic change in breeding success and diet in 2005 and 2006, a time period when upwelling was delayed and weak, causing changes in the abundance of krill, the auklets' primary prey. (Source: PRBO Conservation Science, unpubl. data)
  • Black-footed Albatross: Black-footed Albatrosses (Diomedea nigripes) nest on the northwestern Hawaiian Islands and are seasonally common and can be locally abundant within the sanctuary in the summer (NCCOS 2007, Cordell Bank sanctuary, unpubl. data, PRBO Conservation Science, unpubl. data). Analysis of nest count data of Black-footed Albatrosses from Midway, Laysan, and the French Frigate shoals indicated an increasing trend in breeding birds over the long time period (1922-2005), but a declining trend in the breeding population over the past 15 years (Naughton et al. 2007). Similarly, local patterns of Black-footed Albatross abundance in the central and northern California region (Monterey to Bodega Bay) from at-sea surveys indicate an average decrease in density of 18% between the time periods of 1985-1994 and 1997-2006, and overall cyclical trends in abundance (Ainley and Hyrenbach 2007). Populations are impacted by long-line mortality in areas outside of the sanctuary (Lewison and Crowder 2003), these impacts could eventually be observed at the Cordell Bank sanctuary. These albatrosses are also known to ingest and feed plastic to chicks, which can as a result die of starvation (Sievert and Sileo 1993, Gould et al. 1997). However, because albatrosses live up to 50 years, the influence of these impacts on population trends and the abundance of birds in the sanctuary are slow to emerge.

  • Sooty Shearwater: Sooty Shearwaters (Puffinus griseus) are one of the most abundant seabirds in the sanctuary (Cordell Bank sanctuary, unpubl. data) as well as in the California Current System during summer (Figure 40).
    Figure 40. . Sooty Shearwaters are one of the most abundant seabirds in the sanctuary.  Photo: Steve Howell, CBNMS.
    Figure 40. . Sooty Shearwaters are one of the most abundant seabirds in the sanctuary. (Photo: Steve Howell, CBNMS).
    Flocks with thousands of individuals pass through the sanctuary in summer and fall (NCCOS 2007, PRBO Conservation Science, unpubl. data, Cordell Bank sanctuary unpubl. data), feeding in the productive waters of the northeast Pacific while away from their nesting islands in Chile and New Zealand. Worldwide populations are currently in decline, with high mortality due to bycatch in various fisheries (U.S. Fish and Wildlife Service 2006). Local patterns of Sooty Shearwaters from at-surveys in the central and northern California region (Monterey to Bodega Bay) also indicate decreasing trends in abundance between the time periods of 1985-1994 and 1997-2006 (Ainley and Hyrenbach 2007).

  • California sea lion: California sea lions (Zalophus californianus) are one of the most abundant pinnipeds found in the sanctuary, with highest abundance from summer through early spring (Cordell Bank sanctuary, unpubl. data) when animals are not on the breeding grounds on the Channel Islands and Año Nuevo. Data suggest that El Niño events (depending on severity, timing, length, and frequency) decrease the population growth rate (Caretta et al. 2007) as well as their distribution and abundance within the area (Lowry and Forney 2005). In recent years, the population has been growing at 5.4% to 6.1% per year (Carretta et al. 2007).

  • Humpback whale: Cordell Bank and the other West Coast sanctuaries provide important foraging grounds for humpback whales (Megaptera novaeangliae), which are seasonally abundant, migrating into the sanctuary during late spring, summer and fall to feed in its productive waters (NCCOS 2007, PRBO Conservation Science, unpubl. data, Cordell Bank sanctuary, unpubl. data). They are generalist feeders, but prey heavily on small schooling fish and krill. The eastern north Pacific stock is listed as federally endangered, and there is evidence to suggest a positive population trend (Carretta et al. 2007).

  • Blue whale: Cordell Bank and the other west coast sanctuaries provide important foraging grounds for migrating blue whales (Balaenoptera musculus) in summer and fall (NCCOS 2007). These whales feed primarily on krill; thus, their use of sanctuary habitats is expected to vary with krill abundance. A change in the distribution of blue whales in 2005 and 2006 (PRBO Conservation Science, unpubl. data, Cordell Bank sanctuary, unpubl. data) is probably a response to changing oceanic conditions and reduced krill abundance in the region during these years (Peterson et al. 2006). The population of the eastern north Pacific stock of blue whales appears to be growing (Carretta et al. 2007).

13. What is the condition or health of key species and how is it changing?

The condition or health of key species in the sanctuary is rated as good  and not changing.  Research conducted at Cordell Bank in the 1980s (Okihiro et al. 1992) documented the occurrence and frequency of lesions on several species of rockfish, but the cause was not determined. Mortality events for some marine mammals and seabirds are related to domoic acid poisoning associated with red tides  or phytoplankton blooms (Scholin et al. 2000, Work et al. 1993). These events are often discovered when organisms wash up on beaches and have not been linked to the Cordell Bank sanctuary. The occurrence of domoic acid poisoning appears to be more prevalent in southern California, but events have occurred as close as Monterey Bay (Work et al. 1993).

Natural fluctuations in body condition and health of key species are caused by changing oceanic conditions that affect food supplies. Reduced ocean productivity resulting from anomalous conditions has been related to poor condition of seabirds (Sydeman et al. 2006), marine mammals and fishes. While these biological conditions are thought to be primarily a result of natural variations, the sanctuary is concerned that continued ocean warming, changes in upwelling timing and intensity, and reduced productivity associated with long term climate change could impact the condition and health of key species.

14. What are the levels of human activities that may influence living resource quality and how are they changing?

The levels of human activities that may influence living resource quality in the offshore environment are rated "fair" and "improving." Specific activities that have the potential to influence living resource quality include fishing and associated habitat disturbance, vessel traffic (discharge, oil spills, noise, collision), and marine debris (derelict gear and plastics), all of which may influence living resource quality in the sanctuary. Fishing activity has been severely restricted to protect habitat and overfished rockfish populations (see Figure 23, in pressures section) and overall landings of various fisheries have declined in recent decades (Figure 21). Shipping activity remains constant, averaging about 2000 commercial vessels a year passing through the sanctuary (U.S. Coast Guard, unpubl. data). The amount of derelict fishing gear should not be increasing within the sanctuary, due to the current restrictions on bottom tending fishing activities. It is unknown how growth in the human population, especially in coastal areas, is impacting the levels of other marine debris types.

Living Resources Status and Trends
table
# Status Rating Basis For Judgement Description of Findings
9. Biodiversity
up arrow
Overharvest of some rockfish populations, but recent stock assessments suggest some overfished populations are increasing. Changes in abundance and distribution of many taxa linked to changing ocean conditions. Selected biodiversity loss has caused or is likely to cause severe declines in some, but not all ecosystem components, and reduce ecosystem integrity.
10. Sustainable Fishing
up arrow
Overfishing of some rockfish and prior fishing impacts; closures and gear restrictions appear to be effective. Extraction may inhibit full community development and function and may cause measurable but not severe degradation of ecosystem integrity.
11. Non-indigenous Species
?
No known non-indigenous species; but data are sparse. N/A
12. Key Species
up arrow
Overharvest of some rockfish populations, but recent stock assessments suggest some overfished populations are increasing. Changes in abundance and distribution of many taxa linked to changing ocean conditions. The reduced abundance of selected keystone species may inhibit full community development and function, and may cause measurable, but not severe, degradation of ecosystem integrity; or selected key species are at reduced levels, but recovery is possible.
13. Health of Key Species
-
Changes in condition appear to be caused by natural events. The condition of key resources appears to reflect pristine or near-pristine conditions.
14. Human Activities
up arrow
Influences on living resources include fishing and associated habitat disturbance, vessel traffic (discharge, noise, collision), and marine debris (derelict gear and plastics). Selected activities have resulted in measurable living resource impacts, but evidence suggests effects are localized, not widespread.

Maritime Archaeological Resources

To date, there are no documented shipwrecks in the Cordell Bank sanctuary. However, the Farallon Islands and the mainland coast north of the Golden Gate have historically provided hazardous navigational obstacles to shipping. Year-round fogs and dangerous winds and storms often led ships to rocks and beaches, to be pounded by the Pacific swells. Fierce currents sweep into and out of the entrance to the Golden Gate. Many known shipwrecks litter the floor of the nearby Gulf of the Farallones sanctuary. Therefore, it is possible that shipwrecks exist within the boundaries of Cordell Bank National Marine Sanctuary and will eventually be identified.

Records indicate that 430 vessel and aircraft losses were documented between 1595 and 1950 along California's Central Coast from Cambria north to Bodega Head: 173 in the Gulf of the Farallones sanctuary and 257 in the Monterey Bay sanctuary. To date, none have been documented within the Cordell Bank National Marine Sanctuary.

The abundance of shipwrecks along the California coast warrants future underwater exploration of these resources. Cordell Bank sanctuary is working with the Gulf of the Farallones and Monterey Bay sanctuaries to design efforts to ensure public awareness, understanding, appreciation, and sustainable use of the historical, cultural, and archaeological resources. In a team effort, the three sanctuaries are working toward identification and assessment of documented shipwrecks, some of which may pose significant environmental hazards; to protect sites from unauthorized disturbance; and to develop heritage partnerships and programs.

Maritime Archaeological Resources Status and Trends
table
# Status Rating Basis For Judgement Description of Findings
15. Integrity
?
No documented underwater archaeological sites N/A
16. Threat to Environment
?
No documented underwater archaeological sites N/A
17. Human Activities
?
No documented underwater archaeological sites N/A

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