Methods and Protocols
This report is intended to convey the status and trends of the ecological and cultural resources of the Channel Islands sanctuary. In principal, the strategic plan for reporting the condition of sanctuary resources includes a targeted monitoring and evaluation framework to support adaptive management decisions (NMSP 2004; pg. 3). In this framework, specific management needs are used to identify technical questions. Answers to these questions are derived from monitoring that is both effective and economical. The questions identified in this condition report and the decisions they support are examples of such framework components.
Unfortunately, available financial resources limit the amount of data, analysis, and synthesis to quantitatively address the questions presented in this condition report. As pointed out in the Monitoring Framework for the National Marine Sanctuary Program (NMSP 2004):
“In the past, monitoring in the sanctuaries proceeded primarily on a site-by-site basis, with independent development of monitoring programs tailored to address some, but not all of the priority information needs of the sanctuaries…
Monitoring in the sanctuaries has generally been characterized by substantial dependence on federal, state, and local governmental partners, academia, and volunteers, both for project funding and field support. Unfortunately, inconsistent funding and changing mechanisms for the distribution of funds have affected program stability, leaving at risk our knowledge of the natural and cultural resources the program is directed to protect. Furthermore, most current monitoring in the NMSP is not coordinated regionally or nationally, either among the sites, or between the sites and germane non-sanctuary programs. One result has been the inability to generate long-term data sets that would otherwise contribute important information on regional environmental changes.” (NMSP 2004; pg. 7)
This program-wide characterization is true for the Channel Islands sanctuary. In the absence of targeted, stable monitoring along with synthesis and analysis performed to address the questions, the authors of this report have relied heavily on the expertise and best professional judgment of local researchers and authorities. Thus, while targeted monitoring is critical for a scientifically robust condition report, in practice the Channel Islands sanctuary at the present time has to rely on 1) monitoring that was designed to answer other needs and may have a limited ability to address these specific questions; 2) assembling a variety of diverse data types; and 3) expert professional judgment to develop new inferences and assess overall sanctuary conditions based on these diverse data types.
In an effort to document the information and the process used to arrive at the conclusions in this report, all contributors were asked how much of their assessment was derived directly from monitoring data, from data published in peer-reviewed literature, or from their own professional experience and judgment. Specifically, each contributor was asked to report the relative role of a) explicit, quantitative decision support models, b) management guidelines or benchmarks, or c) professional judgment in translating the information available to a status and trend ranking. Detailed results of this survey are available on request. General findings were that professional experience and judgment constituted many of the conclusions in this report, and decision support models and ecosystem benchmarks were not used when there was an absence of targeted, long-term monitoring data. More information about the methods used in compiling the report can be found in Developing this Report section of this Web site.
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.
Judging an ecosystem as having "integrity" implies the relative wholeness of ecosystem structure and function, along with the spatial and temporal variability inherent in these characteristics, as determined by the ecosystem's natural evolutionary history. Ecosystem integrity is reflected in the system's ability to produce and maintain adaptive biotic elements. Fluctuations of a system's natural characteristics, including abiotic drivers, biotic composition, complex relationships, and functional processes and redundancies are unaltered and are either likely to persist or be regained following natural disturbance.
Water
1. Are specific or multiple stressors, including changing oceanographic and atmospheric conditions, affecting water quality?
Stressors on water quality in the sanctuary, specifically the impacts of diatom blooms, and possibly the conditions causing them, may preclude full development of living resources assemblages and habitats, but are not likely to cause substantial or persistent declines. For this reason, the rating for this question is “good/fair,” however the trend is “undetermined” because of a lack of monitoring data for some parameters. Although significant sediment plumes from mainland rivers are visible from satellite images during the satellite images during the rainy season (Figure 20), storm events are rarely intense enough for these plumes to reach the islands (Otero and Siegel2004). Sediment toxicity is lower in the sanctuary than in the Southern California Bight (Bay et al. 2005). Sampling conducted by the Southern California Coastal Water Research Project (a collaborative research institute for coastal environmental research) typically measures the highest water quality in and around the sanctuary, suggesting that water quality impacts from regional anthropogenic point- and non-point pollutant discharges are significantly mitigated by distance from the mainland and have probably declined over several decades due to improved regulation and management by state and federal agencies.
Since 2001, there has been an apparent increase in diatom blooms. These were identified as the diatom Pseudo-nitzschia which produces the neurotoxin domoic acid (Anderson et al. 2008), a potent neurotoxin that can cause neural damage, disorientation, short-term memory loss and even seizures, brain damage, and death in seabirds, such as cormorants and gulls, and marine mammals, such as seals and sea lions. These blooms appear to be increasing in intensity and length of season each year (Busse et al. 2006, Schnetzer et al. 2007) and they can be harmful or fatal to seabirds and marine mammals. In recent years, there have been extensive marine animal mortality events attributed to domoic acid (Gulland 2000, Scholin et al. 2000).
The effects of global climate change are currently not well understood but could adversely affect water quality through changes in ocean chemistry, seawater temperature increases, and changes in upwelling and oceanographic patterns.
2. What is the eutrophic condition of sanctuary waters and how is it changing?
The offshore location of the islands protects the sanctuary from much of the runoff from the mainland. Therefore, eutrophic conditions do not appear to have the potential to negatively affect living resources or habitat quality. For this reason, the rating for this question is "good and not changing." The sanctuary does not experience much, if any, nutrient enrichment from mainland discharges and runoff. Nutrient delivery from mainland coastal streams and rivers is rather minimal and has been shown to account for a small portion of the annual nitrogen budget for the Santa Barbara Channel (McPhee-Shaw et al. 2007). In addition, the islands are a national park and have minimal development so there is little nutrient enrichment from streams located on the islands themselves. However, nutrient inputs generated at the islands, such as from marine mammals which historically had modest impacts, may now be affecting benthic community structure due to the synergistic impacts of multiple stressors (S. Katz, CINMS, pers. obs. 2008.). It is possible that there may be some localized effects of sewage from vessels that visit the islands, but this has not been measured adequately. In addition, discharge of untreated sewage was prohibited out to three miles from the islands and in March 2009 it became prohibited throughout the sanctuary. Spring phytoplankton blooms are primarily driven by seasonal upwelling of new nutrients from deep waters, and while there has been an apparent increase in the frequency and intensity of harmful diatom blooms (Anderson et al. 2008), the relationship between these blooms and natural and anthropogenic inputs is complex and studies are not yet conclusive (Schnetzer et al. 2007).
3. Do sanctuary waters pose risks to human health?
No known illnesses have been reported from eating shellfish harvested from the Channel Islands sanctuary. However, several potential risks to human health do exist. For this reason, the rating for this question is rated as “good/fair and not changing.” For example, recreationally harvested shellfish species such as scallops and clams that are harvested during Pseudo-nitzschia blooms may cause shellfish poisoning in humans (Novelli et al. 1992). Quarantines are established by the state of California during these outbreaks.
A potential threat of swimming in the ocean is illness resulting from contact with harmful bacteria. However, there are no known health risks from swimming in sanctuary waters. The sanctuary is not subject to major sources of human fecal pollution. It is unlikely that viruses and other pathogens from mainland sewer discharges and runoff could reach the islands intact and virulent due to dilution, exposure to sunlight, and salinity. Significant elevated levels of harmful bacteria from vessel discharges were not detected in a small study conducted for the sanctuary by Santa Barbara Channelkeeper (Altstatt 2007).
4. What are the levels of human activities that may influence water quality and how are they changing?
Although there are many activities that have the potential to affect water quality, sanctuary water quality appears not to have suffered significant damage from anthropogenic impacts. Therefore, the rating for this question is "good and not changing." The human activities that affect water quality in the sanctuary are shipping traffic, vessel discharges, contaminants such as DDT, and mainland land use runoff. Each year, approximately 7,000 cargo ships transit through the sanctuary; this number is expected to increase over the long term in response to increases in global trade at the Los Angeles and Long Beach port complex. Little is known about the deposition of airborne contaminants from commercial shipping traffic and the extent and effects of vessel discharges in the sanctuary. Persistent contaminants such as DDT and derivatives from pesticide industries are still detected in sediments decades after production has ceased but in lower amounts in the sanctuary compared to the mainland (Schiff et al. 2006). Mainland runoff does not currently reach the islands in significant amounts (Otero and Siegel 2004) but an increase in pollution from development and agricultural runoff coupled with significant storm events could eventually affect sanctuary water quality.
Water Status and Trends
Status: Good Good/Fair Fair Fair/Poor Poor Undet.
Trends:
▲ Conditions appear to be improving.
- Conditions do not appear to be changing.
▼ Conditions appear to be declining.
? Undeterminted trend.
N/A Question not applicable.
# |
Status |
Rating |
Basis For Judgement |
Description of Findings |
1. |
Stressors |
?
|
Distance from the mainland and regulations limit impacts; sampling generally indicates water quality is better at the islands than the mainland. However, there is concern about an apparent increase in the frequency and extent of diatom blooms. Also, the effects of ocean acidification, although not currently well understood, are expected to have significant impacts. |
Selected conditions may preclude full development of living resource assemblages and habitats, but are not likely to cause substantial or persistent declines. |
2. |
Eutrophic Condition |
|
Mainland runoff does not reach the island in significant amounts and lack of development on the islands means there is little local land-based nutrient inputs; island runoff is minimal. However, there may be localized inputs from marine mammals and possibly vessel discharge. |
Conditions do not appear to have the potential to negatively affect living resources or habitat quality.
|
3. |
Human Health |
|
There are no known occurrences of risks resulting from water contact or seafood consumption at the islands. However, there are known vectors for shellfish poisoning through Pseudo-nitzschia/domoic acid blooms although shellfish poisoning has not been reported in the sanctuary. |
Selected conditions that have the potential to affect human health may exist but human impacts have not been reported.
|
4. |
Human Activities |
|
Many activities are present that have the potential to harm water quality: shipping traffic, vessel discharges, DDT, and mainland land use runoff. However, they are not causing significant damage at this time. |
Few or no activities occur that are likely to negatively affect water quality.
|
Habitat
5. What are the abundance and distribution of major habitat types and how are they changing?
The abundance and distribution of major habitat types in the sanctuary is rated as "fair" based on the past and current levels of human activities that influence the distribution, abundance, and quality of benthic habitats and associated living resources. The trend is "undetermined" due to a lack of information on the extent of harm and the rate and degree of recovery of habitat and associated living resources inside recently established regulatory areas.
Approximately only a third of the sanctuary has been mapped using high resolution imaging, however deepwater areas are not well studied thus limiting the ability to quantitatively estimate the status of sanctuary habitat and how it is changing over time. Although a thorough study of the local effects of past and present trawling has not been completed in the Channel Islands sanctuary, it has been well documented to alter marine communities elsewhere. Experts believe the level of trawling activity that historically took place in the sanctuary may have degraded deep soft-bottom and some hard-bottom habitats (J. Engle, UCSB, pers. comm. 2007). Trawling has significantly decreased from historic levels as a result of the recently established Cowcod Conservation Area (2000), Rockfish Conservation Area (2002), a ban on spot prawn trawling in state waters (2003), and the creation of marine reserves (in state waters in 2003 and in federal waters in 2007) (Figure 21). Other types of fishing, such as trap gear, may also impact benthic habitat. Lost fishing gear such as nets and line continue to impact benthic areas. Considerable amounts of marine debris adversely affect pelagic and shoreline habitats (Richards 1993).
6. What is the condition of biologically structured habitats and how is it changing?
The condition of biologically structured habitats in the sanctuary is rated as "fair and not changing." The historical harvest of important predators, including lobsters and sea otters, has destabilized highly diverse and productive kelp forest communities, resulting in a major, long-term loss of giant kelp and understory habitat-forming algae (especially at Santa Barbara, Anacapa, and eastern Santa Cruz Island) (Behrens and Lafferty 2004, Lafferty 2004). In addition, the destabilization of kelp forest rocky reef habitats has resulted in extensive, persistent, poor-quality urchin barrens, which are areas that have been denuded of algae by sea urchins. In the short term, however, kelp abundance in the Channel Islands region increased during 2003-2007 compared to the period 1998-2002 (CDFG et al. 2008). This increase was greater inside marine reserves than outside (CDFG et al. 2008).
Although a thorough study of the effects of fishing activities on habitats has not been completed, trawling and trapping activities have likely degraded deep hard-bottom coral communities (including cup corals, purple hydrocoral, and gorgonian sea fans) to some unknown extent (J. Engle, UCSB, pers. comm. 2007). Recovery may be possible as a result of the creation of reserves and other relatively recent regulations that now prohibit trawling and trapping in many areas. Anchoring damages eelgrass and kelp habitats, and recreational anchoring is expected to increase. A population increase of white urchins in the 1980s resulted in a severe decline in eelgrass habitats at Anacapa Island (Engle and Miller 2005). Transplantation efforts by Santa Barbara Channelkeeper have resulted in a minor recovery of eelgrass (Altstatt 2005). Dramatic declines in rocky intertidal mussel bed community diversity as well as variable declines in biomass and bed thickness have occurred from the 1970s to 2000s at Southern California island and mainland survey locations, with declines possibly due to a climate regime shift toward warmer sea temperatures. However, it is unclear whether this is the result of a natural cycle or anthropogenically driven global climate change (Smith et al. 2006a, b).
7. What are the contaminant concentrations in sanctuary habitats and how are they changing?
The relative remoteness of the Channel Islands sanctuary from mainland pollution sources and protections afforded by the Channel Islands National Park and the Channel Islands sanctuary have resulted in lower contaminant levels at the islands as compared to the mainland, and therefore the rating for this question is "good/fair and improving." Production of the pesticide DDT was halted in the early 1970s and sediment contamination is much lower in the sanctuary compared to the rest of the Southern California Bight (Schiff et al. 2006). Although production ceased, DDT and its derivatives are still found in sediments, pelagic forage fish, invertebrates (Jarvis et al. 2007), and marine mammals (Blasius and Goodmanlowe 2008), indicating that the toxins are still accessible to marine organisms in the Southern California Bight. Suspended sediment plumes from mainland storm runoff, which may contain pollutants, do not commonly reach the islands (Otero and Siegel 2004). Illegal discharges from vessels occur to an unknown extent and vessel groundings occasionally release petroleum and other chemicals. Several small vessels have run aground in the sanctuary in recent years with associated minor fuel and shipboard chemical spills (i.e., lubricants, solvents, paints) that quickly dissipate and/or breakdown. Potential oil and other chemical spills from platforms and vessels remain a threat.
8. What are the levels of human activities that may influence habitat quality and how are they changing?
The level of human activity impacting sanctuary habitat quality is rated as "fair." The trend of human impacts is "improving" because trawling and trapping activities have significantly decreased since the creation of no-take reserves and other fishery regulations. Past harvesting of sea otters and continued substantial commercial and sport harvest of fish and invertebrates have reduced habitat quality, particularly on rocky reefs by directly removing top predators and community dominants and indirectly reducing productive, habitat-forming seaweed assemblages (via release from predation of grazers that results in an increase in herbivory). Marine debris (including dumped trash and lost fishing gear that can continue to trap animals), illegal vessel discharges, and anchoring can harm or damage sanctuary habitat. Oil platform production and commercial vessel traffic continue to be potential sources of catastrophic impacts should major spills or accidents occur. Commercial and recreational fishing activities have declined in reserve areas that are off-limits to fishing, but visitation by non-consumptive users has remained nearly constant (Senyk et al. 2008). Enforcement of marine reserves appears to be effective and outreach efforts have increased public awareness of regulations (CDFG et al. 2008).
Habitat Status and Trends
Status: Good Good/Fair Fair Fair/Poor Poor Undet.
Trends:
▲ Conditions appear to be improving.
- Conditions do not appear to be changing.
▼ Conditions appear to be declining.
? Undeterminted trend.
N/A Question not applicable.
# |
Status |
Rating |
Basis For Judgement |
Description of Findings |
5. |
Abundance/ Distribution |
?
|
Past trawling, lost fishing gear, and marine debris have harmed habitats, although little is known about deepwater habitats. Recent trawl bans and other regulations may improve conditions. |
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 |
|
Long-term loss of giant kelp and understory habitat-forming algae, trawling damage to hard-bottom coral communities, anchor damage to eelgrass and kelp, declines in eelgrass as a result of white urchin increases, decline in mussel bed community diversity, biomass, and bed thickness. Short term increases in kelp, an eelgrass restoration project, reserves, and trawl regulations may help habitats recover. |
Selected habitat loss or alteration may inhibit the development of living resources and may cause measurable but not severe declines in living resources or water quality.
|
7. |
Contaminants |
|
Distance from mainland reduces impacts from mainland discharges, DDT still detectable but some species recovering, vessel discharges are present but regulations have kept contamination at low levels. |
Selected contaminants may preclude full development of living resource assemblages, but are not likely to cause substantial or persistent degradation.
|
8. |
Human Activities |
|
Impacts to habitat quality may have resulted from historic or current direct or incidental extraction of biogenic species, marine debris, vessel discharges, and anchoring; creation of reserves and other fishing regulations may improve conditions. |
Selected activities have resulted in measurable habitat impacts, but evidence suggests effects are localized, not widespread.
|
Living Resources
9. What is the status of biodiversity and how is it changing?
Biodiversity is variation of life at all levels of biological organization, and also commonly encompasses diversity within a species (genetic diversity) and among species (species diversity), and comparative diversity among ecosystems (ecosystem diversity). This report focuses on species diversity. Overall the biodiversity in the Channel Islands sanctuary is rated as "fair" and the trend is "unknown." Although thorough historic and current comparative evaluations of species are not available to fully measure biodiversity status, there are key components that have been altered and indicate compromised biodiversity. Sanctuary-wide extraction of fish and invertebrates by commercial and recreational fishing has led to conditions that are far from pristine for all ecosystems. Recreational and commercial fishing has removed fish, such as sheephead, kelp bass, and rockfish, and invertebrates, such as lobster and abalone, and this extraction has altered the ecosystem. At San Miguel, Santa Rosa, and the western portion of Santa Cruz Island, where fishing pressure is lower, there are lush kelp forests with high biodiversity. However, even these locations are missing key species such as sea otters and larger individuals of some fish species (D. Kushner, CINP, pers. comm. 2007). At the eastern end of the island chain, Anacapa Island, Santa Barbara Island, and the eastern portion of Santa Cruz Island where fishing pressure is greater, there has been an overall decline in biodiversity in many areas (D. Kushner, CINP, pers. comm. 2007). However, recent studies comparing no-take reserves to fished areas show that there are more species of fish inside reserves than outside (CDFG et al. 2008).
Many areas that previously supported kelp forests or eelgrass beds are now dominated by one or more species of echinoderms (urchins and brittle stars) and have lower biodiversity (J. Altstatt, Santa Barbara Channelkeepe r (SBCK), pers. comm. 2007, J. Engle, UCSB, pers. comm. 2007) (Figure 22). In some nearshore areas around Anacapa, brittle stars have been found at densities greater than 1000 per square meter ( Altstatt 2005). Although some species can coexist with urchins, areas dominated by brittlestars appear to prevent the colonization of other species (J. Altstatt, SBCK, pers. comm. 2007). In addition, throughout the sanctuary abalone, rockfish, shark, and swordfish populations have been severely depleted (D. Richards, CINP, pers. comm. 2007). In the intertidal community, there has been a decrease in abundance and diversity of mussel bed communities (Smith et al. 2006a, b). Less is known about the biodiversity in deepwater habitats, where technological challenges make studying this habitat difficult. Advances in technology are just now emerging to make this more feasible.
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. Because this is the sanctuary’s first condition report, 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. Subsequent reports will take a more contemporary view of the ecosystem level impacts of fishing. 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.
The status of environmentally sustainable fishing is rated “fair/poor” and the trend is “improving.” Environmentally sustainable fishing protects the fish and the environment in which they live while allowing responsible use of the species that come from that environment. It is designed to protect the integrity of ecosystem structure, productivity, function and biodiversity, including habitat and associated dependent and ecologically related biological communities. Historical records indicate commercial and recreational fishing at the Channel Islands has occurred since the 1800s and sustenance fishing occurred as early as thousands of years ago. Marine communities at the Channel Islands are subject to complex pressures and interactions, and many targeted species are long lived. Therefore, fishery management actions aiming to allow population recovery may experience a long lag period before changes are observed.
Despite the long history of extraction, fisheries managers at state and federal resource agencies appear optimistic that fishery stocks are being managed sustainably. The NOAA National Marine Fisheries Service (NOAA Fisheries) uses the following definitions that set the standards by which Federal fisheries managers determine the status of federally managed stocks (NOAA Fisheries 2008):
- A stock that is subject to overfishing has a fishing mortality (harvest) rate above the level that provides for the maximum sustainable yield.
- A stock that is overfished has a biomass level below a biological threshold specified in its fishery management plan.
By these definitions and NOAA Fisheries research, none of the federally managed fisheries in the area of the sanctuary are subject to overfishing, and only four Pacific groundfish species remain in an overfished status. These four remaining overfished species – cowcod, bocaccio, dark-blotched rockfish, and yelloweye rockfish – are all covered by rebuilding plans and are making progress at meeting their rebuilding targets (NOAA Fisheries 2008). Likewise, state fisheries managers are optimistic about improved environmental conditions and more sustainable fisheries for those species managed by the state of California (such as squid, spiny lobster, red sea urchin, sea cucumber, kelp bass, rock crab, prawns, and sheephead) as a result of recent regulatory changes.
However, the question of environmentally sustainable fishing considered for this report is broader than stock assessments and incorporates concepts such as size structure, trophic interactions, biodiversity, bycatch removal, and ecosystem integrity. Local experts report conditions and long-term changes in the fish and invertebrate populations and communities that suggest that environmentally sustainable fishing goals are compromised, at least until a number of key populations have recovered from past overfishing.
At least in part as a result of past or historic fishing, declines have occurred in several species of sharks, giant sea bass, swordfish, various rockfish, and abalone populations (Leet et al. 2001, Rogers-Bennet et al. 2004). Even though the harvest of certain species has ended in a few areas, populations remain well below historic numbers. For example, as a result of a combination of fishing and disease, black and white abalone populations have decreased to the point that they are listed as federally endangered species, and red abalone are rare in Southern California, except at San Miguel Island. Populations of other species have shifted towards smaller sizes, such as red sea urchins, lobster, and sheephead in some areas where fishing occurs (D. Richards, CINP, pers. comm. 2007). Size is an important factor in environmentally sustainable fishing because larger organisms have higher fecundity and make a greater contribution to healthy, robust populations. Changes in size, abundance, and diversity can have effects throughout the food web. For example, extraction of lobster has led to an increase in urchins and a decrease in kelp abundance in some areas (Behrens and Lafferty 2004).
Another concern is the methods used in some fisheries. Gill netting, which can have substantive bycatch, is allowed in some areas of the sanctuary, but not within one mile of the islands. The Channel Islands sanctuary defines bycatch as catch of non-target species; note however, that NOAA Fisheries does not consider organisms as bycatch if they are marketable, and therefore distinguishes between economic and regulatory bycatch. Gill netting in the sanctuary generally targets white sea bass, flatfish, swordfish, and sharks, but can entangle many other species, including other fin fish, mammals, birds, and turtles. In addition, lost lobster or fish traps can indiscriminately capture marine organisms.
Finally, there is concern about indirect effects of fishing to other animals in the sanctuary. Seabird researchers are concerned abouteffects of: a) fishing of northern anchovy and Pacific sardine on prey availability for Brown Pelicans [note, however, that the federal Coastal Pelagic Species Fishery Management Plan incorporates 150,000 metric tonnes for ecosystem forage needs]; b) bycatch from gill-net fishing on cormorants and alcids; c) bycatch of pelicans from recreational fishing; and d) disturbance of colonial surface-nesting seabirds and roosting seabirds by fishing, diving, and boating activities near shore: and e) light pollution impacts (i.e., increased avian predation or increased nest abandonment) from squid fishing on small seabirds (e.g., Xantus’s Murrelets, Ashy Storm-Petrels) that visit nesting colonies only at night or collide with lighted structures or vessels (Gress and Anderson 1983, Carter et al. 2000, Carter et al. 2008). Studies are needed to better assess fishing impacts on seabirds, especially boat disturbance and light pollution.
In recent years many new regulations have gone into effect including federal abalone fishery closures, a network of marine reserves regulated by both the state and federal government, a gill net ban within one mile of the islands, Rockfish Conservation Area, Cowcod Conservation Area, spot trawl ban, Essential Fish Habitat designation, and new regulations on nearshore fishery species (see Figure 21, Question 5). All of these regulatory actions contribute to the “improving” trend of this issue. However, historic fishing pressure has had impacts that are still evident in the environment. Furthermore, fishing is still allowed in most of the sanctuary and there are significant gaps in our knowledge of fishery effects, basic life history, and ecosystem dynamics that impede management certainty that fishing is not having undue and unexpected deleterious effects on overall ecosystem health.
11. What is the status of non-indigenous species and how is it changing?
The status of non-indigenous species in the marine environment is rated “good” and the trend is “getting worse” because although invasives do not appear to be much of an issue at present, there are several algal species (including Undaria pinnatifida, Sargassum filicinum, and Caulacanthus ustulatus) that are appearing in Southern California and have proliferated at Santa Catalina Island and other areas (Miller et al. 2006). The Japanese brown alga Undaria pinnatifida has been found in Santa Barbara and Ventura Harbors and the brown alga Sargassum filicinum has been found at Santa Catalina Island (Miller et al. 2006). The Asian red algaCaulacanthus ustulatus has been observed at one site at Anacapa Island. If these species become established and widespread at the islands, they could outcompete native species and adversely affect species richness and diversity patterns in the invaded habitats. Several ongoing monitoring programs record observations of invasive species as part of their standard procedures, so the sanctuary is hopeful that early detection can be achieved.
12. What is the status of key species and how is it changing?
The overall status of key species in the sanctuary is rated as “fair” and the trend is “not changing.” Key species in the sanctuary include urchins, sunflower star, California spiny lobster, sheephead, giant sea bass, rockfish and other fish species, red abalone, and sea otters. Key seabird species include Brown Pelicans, Brandt’s Cormorants, Cassin’s Auklets, Xantus’s Murrelets, and Ashy Storm-Petrels. Four species of whales are key species: fin, humpback, blue, and gray.
In areas where kelp forests are present, some key fish species have increased (D. Kushner, CINP, pers. comm. 2007) and reserves may be helping fish species to recover (CDFG et al. 2008). Populations of giant sea bass, once abundant, have improved in recent years, but levels are still well below historic populations and they remain vulnerable to both legal incidental harvest in gill net fisheries and poaching (Leet et al. 2001). Although once persistent, kelp beds have become more transient in nature; of 16 sites originally designated by the National Park Service in 1981 as kelp forest monitoring sites, only one, within a long-standing no-take reserve at Landing Cove on Anacapa Island, has remained persistent over a 20-plus year survey (Lafferty and Behrens 2005). Kelp may be reduced as a result of fishing impacts to other species, such as spiny lobster, which prey on sea urchins (Lafferty 2004). When predators are removed, sea urchins can increase and thus reduce kelp on which they graze. Red abalone and sea otters are key species that were once abundant in the sanctuary and have been depleted as a result of disease and historic harvesting. Both species are now protected, but recovery has not yet been observed. Both black and white abalone, which were once common in the sanctuary, are now listed under the federal Endangered Species Act.
Deepwater habitat includes a majority of area in the sanctuary and contains key species unique to that habitat. However, little is known about this habitat, and key species in deepwater cannot be identified at this time. Monitoring in deep water is logistically challenging and expensive and will require working with remotely operated vehicles (ROVs), autonomous underwater vehicles (AUVs), or submersibles. The sanctuary is working to develop a deepwater monitoring plan and acquire funding to be able to address this issue.
Seabirds feed at a high trophic level and are good indicators of ecosystem health. There is a variety of impacts to seabird populations. More than 30 years after DDT was banned, there have been dramatic improvements in Brown Pelicans (Gress 1995, unpubl. data). In 2008, the U.S. Fish and Wildlife Service proposed to remove California Brown Pelicans (Figure 23) from the U.S. endangered species list. Brandt’s Cormorant populations fluctuate dramatically with population declines during major El Niño events (1992-93, 1998), and population increases in intervening years (Carter et al. 1996, Capitolo et al. 2008). In general, cormorants are maintaining large populations and have recovered to a substantial degree from many past human disturbance factors and pollutant issues. Cassin’s Auklet populations are declining, apparently in relation to changes in prey resources possibly related to climate change (Adams 2008). About a third to a half of the world population of this species occurs in the sanctuary (Karnovsky et al. 2005, Carter unpubl. data), and it was listed by the state of California as threatened in 2004 (Burkett et al. 2003), with a federal listing decision pending. Xantus’s Murrelets are declining at Santa Barbara Island due toimpacts from high levels of egg predation by high population levels of native deer mouse, and high levels of adult predation by avian predators (e.g., owls, falcons, and gulls) (Burkett et al 2003). Recent invasive rat eradication from Anacapa Island is helping the nesting population at this location to recover (Whitworth et al. 2006). Ashy Storm-Petrels are found almost exclusively in California, in addition to a colony in Northern Baja, and the Channel Islands sanctuary hosts about half of the world population (Carter et al. 1992). This species was petitioned in 2007 to be listed under the federal Endangered Species Act. Ashy Storm-Petrels in the Channel Islands may be declining due to continuing effects of pollutants (e.g., DDT and PCB), high predation of adults by avian predators, human disturbance, and light pollution (Carter et al. 2008). After an absence of breeding for many years, Tufted Puffins bred at San Miguel Island from 1991-1997 but no longer breed there today (H. R. Carter, Carter Biological Consulting, unpubl. data). Rhinoceros Auklets have bred at San Miguel Island since 1991 and were not known to breed there in the past (Carter et al. 1992, unpubl. data). Common Murres have not bred at San Miguel Island since the early 1900s, but birds have been attending breeding habitats since 1999 and may soon recolonize (H.R. Carter, Carter Biological Consulting, unpubl. data).
Raptors are top trophic predators that feed on seabirds, fish, or scavenge marine mammal carcasses. Raptors at the Channel Islands - Peregrine Falcons, Bald Eagles, and Osprey - were extirpated from the Channel Islands by the effects of DDT. Peregrine Falcons have returned to breed in relatively large numbers in the Channel Islands after significant efforts to reintroduce them to the islands. Efforts to reintroduce bald eagles to Santa Cruz Island have had initial moderate success, with successful natural breeding, nesting, and fledging by several adult pairs. Osprey have not yet been reintroduced.
Four species of baleen whales use the sanctuary for significant feeding grounds or migration routes: fin, humpback (Figure 24), blue, and gray whales can be found in the sanctuary during parts of the year. Fin whale numbers appear to still be depleted from commercial whaling, and they remain listed as endangered. However, there have been indications of increased sightings of fin whales in many areas and it is expected they are making a recovery from whaling. Data on this is very limited, and increased sightings could be caused by shifts in distribution rather than an actual increase in population size (J. Calambokidis, Cascadia Research, pers. comm. 2008).
Humpback abundance off the U.S. West Coast appears to be increasing steadily at about 8% per year, although there was a slight decline after the 1998 El Ni no (Calambokidis and Barlow 2004, Calambokidis et al. 2005). They are now expected to number around 20,000 in the North Pacific, approaching the numbers thought to exist prior to whaling (Calambokidis et al. 2008). In recent years, humpback whales off California have switched from feeding predominantly on krill to fish (J. Calambokidis, Cascadia Research, pers. comm. 2007). This switch may reflect declines in available krill that could also be affecting blue whales, and possibly other species. This decline in their primary food source may negatively affect humpback abundance in the sanctuary over the longer term.
The blue whale population status over the long term has been improving, but there have been indications of declining conditions in recent years. There was an apparent dramatic decline in blue whale abundance off California in 2001 and 2005 compared to the 1990s (Barlow and Forney 2007). This may be related to evidence of increasing use by blue whales of feeding areas outside California, including waters off Mexico, British Columbia, and Alaska (Calambokidis et al. 2007). Blue whales are exclusively krill feeders and may be more vulnerable to the apparent local declines in krill abundance, based on recent declines in local krill-feeding bird species and the locally observed switch in prey of humpback whales. At this point it is not possible to determine if this change in whale distribution is part of a natural cycle or related to climate change. An additional and emerging threat to large whales is ship strikes, which has affected blue whales locally. In 2007 several dead blue whales were discovered in the region, two of which were confirmed ship strikes. The sanctuary and an interagency subcommittee responded to this event with increased monitoring for the presence of blue whales, and by recommending a voluntary speed reduction for cargo ships in the Santa Barbara Channel during blue whale season (generally in the late summer and fall months).
Gray whales steadily recovered from whaling, and in the 1990s reached what was thought to be pre-whaling numbers. In the late 1990s, the gray whale population experienced a high level of mortality and low calf production, apparently due to a combination of an increasing population and decreases in prey in the Bering Sea. This may have resulted in a decline of about a quarter of the population during this period (J. Calambodokidis, Cascadia Research, pers. comm. 2007).
13. What is the condition or health of key species and how is it changing?
The overall diminished health of key species in the sanctuary is rated as “fair,” however the trend is “undetermined.” For example, overall abalone populations remain depressed at the islands (except at San Miguel Island), there is little indication of any recent recovery, and disease remains a concern. Abalone are susceptible to withering syndrome, and a large portion of the remaining red abalone population seems to harbor the disease, even if individuals do not exhibit symptoms (CDFG 2007). Although black abalone abundances have shown very slight increases in recent years, disease occurrences for this important key intertidal species continue. In 2008, black abalone were listed under the federal Endangered Species Act. Echinoderm diseases (especially in sea urchins and seastars) are common, but little is known about the cause or effects.
Size of marine organisms is important because larger individuals have higher reproductive fitness. Outside of marine reserves (see Figure 21, Question 5), large spiny lobsters are uncommon but have increased inside reserves (CDFG et al. 2008). Though several species of fish (e.g., sheephead and kelp bass) appear to have increased in abundance recently (probably due to favorable oceanographic conditions), their size distribution has not changed appreciably (presumably due to fishing pressure). These fish also remain noticeably small at several of the islands (mainly Santa Barbara, Anacapa, and the eastern portion of Santa Cruz Island) (D. Kushner, CINP, pers. comm. 2007).
Populations of some species of seabirds plummeted as a result of eggshell thinning caused by the pesticide DDT. Since production ceased in the 1970s populations have been recovering (H. Carter, Carter Biological Consulting, pers. comm. 2007,CINP Brown Pelican Web site, Engle 2006, Sydeman et al. 2001, CINP Bald Eagle Web site). In addition to effects on seabirds, fish, invertebrates (Jarvis et al. 2007) and marine mammals (Blasius and Goodmanlowe 2008) have measurable levels of DDT in the Southern California Bight.
Cassin’s Auklets have had high nesting failures in recent years, and this may be a result of reduced food sources due to changing oceanographic conditions (Adams 2008). Xantus’s Murrelets nested later in 2005-2007, though nesting was earlier in 2008 (Whitworth et al. 2006, Whitworth unpubl. data). Ashy Storm-Petrels at Santa Cruz Island have had declines in nesting at some locations as a result of skunk predation and light pollution (Carter et al. 2007, Carter et al. 2008, unpubl. data). These changes may reflect changes in food availability, predation, habitat, or other resources.
14. What are the levels of human activities that may influence living resource quality and how are they changing?
Human activities influencing living resource quality in the sanctuary is rated as “fair and getting worse.” Although there are some impacts that are becoming less severe, these are overwhelmed by others that are getting worse. For example, it appears that improved fishing regulations and marine reserves (see Figure 21, Question 5) may allow populations to recover although historic sanctuary-wide extraction has led to severe declines in some exploited species, such as abalone, lobster, and rockfish. In contrast, there are some impacts that are increasing in frequency and severity. A growing human population provides the potential for increasing visitation which could increase the chance for potential introduction of species and disturbance. Mechanisms of disturbance include anchoring, noise, lights, trash, increased harvest pressure, and illegal fishing.
An increase in recreational diving, kayaking, boating, and wildlife watching could bring harm by disturbing wildlife and habitats. People who land on shore could trample seabird nests or intertidal animals. Wildlife disturbance from recreational boats and disturbance of the seabed from anchoring are also concerns. Eelgrass beds in high-use anchorages such as Scorpion and Prisoners at Santa Cruz Island experience frequent scarring from anchoring (J. Altstatt, SBCK, pers. comm., 2007). Over the long term, shipping traffic is expected to increase in the Santa Barbara Channel, potentially increasing the risk of air and water pollution, a wreck, spill, collision with marine mammals or other vessels, and the introduction of invasive species through ballast water.
Unfortunately, these localized impacts are likely to be overwhelmed in the longer term by the adverse and wide-ranging effects of anthropogenically caused climate change effects on sea level, air and water temperatures, and ocean chemistry.
Living Resources and Trends
Status: Good Good/Fair Fair Fair/Poor Poor Undet.
Trends:
▲ Conditions appear to be improving.
- Conditions do not appear to be changing.
▼ Conditions appear to be declining.
? Undeterminted trend.
N/A Question not applicable.
# |
Status |
Rating |
Basis For Judgement |
Description of Findings |
9. |
Biodiversity |
?
|
Extraction of fish (e.g., sheephead, kelp bass, rockfish) and invertebrate (e.g., lobster and abalone) species has decreased biodiversity and simplified community structures (e.g., dominance of urchins and brittlestars). |
Selected biodiversity loss may inhibit full community development and function and may cause measurable but not severe degradation of ecosystem integrity.
|
10. |
Extracted Species |
|
Declines have occurred in several species of sharks, giant sea bass, swordfish, various rockfish, and abalone populations; recent implementation of marine reserves may improve conditions. |
Extraction has caused or is likely to cause severe declines in some but not all ecosystem components and reduce ecosystem integrity.
|
11. |
Non-indigenous Species |
|
No problematic species have become established; there is concern that invasive algae from mainland harbors and Catalina could reach the islands. |
Non-indigenous species are not suspected or do not appear to affect ecosystem integrity (full community development and function).
|
12. |
Key Species |
|
Removal of key species, including sea otters, led to an increase in urchins and urchin barrens. Some species (black sea bass and lobsters) have shown recent increases, but do not approach historic levels. |
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 |
?
|
Withering foot syndrome in abalone, small size of fished species, low fecundity in sea birds; although some birds have shown recent recovery from historic reproductive impairment from high levels of DDT.
|
The diminished condition of selected key resources may cause a measurable but not severe reduction in ecological function, but recovery is possible.
|
14. |
Human Activities |
|
Increased visitation and potential disturbance along with expected climate change offset gains made in resource protection. |
Selected activities have resulted in measurable living resource impacts, but evidence suggests effects are localized, not widespread.
|
Maritime Archaeological Resources
15. What is the integrity of known maritime archaeological resouces and how is it changing?
The integrity of submerged maritime archaeological resources is rated “fair and getting worse.” A comprehensive inventory of archaeological resources began at the time of sanctuary designation in 1980 and continues today. Approximately 30 archaeological site locations have been inventoried and are in various stages of survey, including site map development and monitoring. Archival research suggests over 140 historic maritime archaeological resources, including ship and aircraft wrecks, may exist in the sanctuary (Morris and Lima 1996). Most of the known shallow water sites are in various stages of degradation due to their close proximity to shore. Sites in shallow water environments within higher energy zones are more likely to be subjected to degradation by waves, shifting sands, and strong currents. Some sites are regularly visited by divers, and in some cases, artifacts have been removed from accessible sites. It is assumed shallow-water relic hunting has declined due to enforcement, education, and the fact that most of the accessible sites have already been pilfered.
Submerged cultural material associated with Native American terrestrial sites has been recorded nearshore as a result of coastal land erosion. There is a possibility of Native American submerged materials in deeper water, in areas occupied during times of lower sea levels thousands of years ago, but such resources have not yet been discovered.
There is a greater uncertainty of the integrity of offshore submerged maritime archaeological resources in depths greater than 120 feet (36 meters). To date, only two deep offshore archaeological sites have been inventoried by NOAA in the Channel Islands sanctuary (WWII era TBF Avengermilitary aircraft and a shipwreck known asBar-bee, both near Anacapa Island). No other evaluations of deepwater archaeological sites have been conducted by other federal, state, or private resource management agencies. Sites in deep water are naturally in better condition than those in shallow water because they are not impacted by strong currents and the cold, deep water environment tends to have fewer biological processes accelerating ship degradation. However, because these sites are intact they may be attractive to looters, particularly those with technical diving capabilities who may still be determined to access sites despite recent enforcement efforts. An additional probable impact in offshore waters is from bottom trawling, but because the majority of wreck locations are unknown, so are the impacts from past trawling. Trawling has recently declined in the sanctuary because of fishing regulations (see Figure 21, Question 5).
The sanctuary works in collaboration with the Channel Islands National Park, California’s State Lands Commission, and Coastal Maritime Archaeology Resources organization to survey and monitor submerged sites annually. To date, one nearshore site (California Gold Rush passenger steamship Winfield Scott, lost 1853) has been added to the National Register of Historic Places (Figure 25).
16. Do known maritime archaeological resources pose an environmental hazard and is this threat changing?
The Channel Islands sanctuary’s inventory of known maritime archaeological resources suggests it is unlikely that shipwrecks within sanctuary boundaries have the potential to pose an environmental hazard to sanctuary resources due to hazardous cargoes and/or bunker fuels; therefore, this question is rated “good/fair” with an “improving” trend. Shipwrecks that once had the capacity to hold bunker fuel and hazardous cargoes have been surveyed and are no longer considered to pose a threat because degradation of hull structure has allowed materials to dissipate. A greater threat to sanctuary resources is from shipwrecks in the contiguous waters just outside the sanctuary boundaries. For example, the bulk-carrier Pacbaroness that sank approximately 10 nautical miles northwest of the sanctuary after a collision in 1987 carried a cargo of 21,000 metric tons of finely powdered copper concentrate, 339,360 gallons of fuel oil, and 10,015 gallons of lubricating oil. Due to the prevailing current and wind, the oil was transported in close proximity of San Miguel Island, considered to be one of the most biologically rich of the islands within the sanctuary. A northerly flowing current became predominant over the wind and carried the oil away from the sanctuary before it reached shore. Other submerged vessels that could pose a threat may include those that have been scuttled by the military to dispose of weapons. A military disposal site exists off Santa Cruz Island; research to date has not identified the existence of hazardous maritime archaeological resources.
17. What are the levels of human activities that may influence maritime archaeological resource quality and how are they changing?
Human activities affecting maritime archaeological resources in the sanctuary are minimal. Therefore, the rating for this question is “fair and improving.” Site looting (where objects are intentionally pilfered from submerged sites) was a major threat to submerged archaeological resources including these historic shipwrecks: California Gold Rush passenger steamerWinfield Scott lost in 1853, 19th-century-built sailing ship Aggi lost in 1915 (Figure 26), 19th-century bark Goldenhorn lost in 1892, 19th-century-built cargo/passenger steamer Cuba lost in 1923 (Figure 27), and 19th-century steamship collier Crown of England lost in 1894. With the successful prosecution of sport divers involved in site looting in the 1980s along with expanded education and outreach programs established by the sanctuary, the risk of looting has declined (Schwemmer 2001). Other potential impacts to archaeological sites include sport divers accidentally causing injury through poor diving techniques such as inadvertently holding onto fragile artifacts or striking them with scuba tanks. Vessel activities, such as anchor drags or modern ship groundings, can also cause serious injury to submerged archaeological resources.
Historical and recent bottom trawling is one probable impact to offshore maritime archaeological resources from which these resources cannot recover. Recently, the numbers of trawlers and areas available to trawling have decreased due to management regulations. With the recent trawl closures, the shift of fishing effort to new areas may increase risk to resources that have not been impacted in the past. Because the majority of wreck locations are unknown, the impacts from historical and recent trawling are unknown.
Maritime Archaeological Resources and Trends
Status: Good Good/Fair Fair Fair/Poor Poor Undet.
Trends:
▲ Conditions appear to be improving.
- Conditions do not appear to be changing.
▼ Conditions appear to be declining.
? Undeterminted trend.
N/A Question not applicable.
# |
Status |
Rating |
Basis For Judgement |
Description of Findings |
15. |
Integrity |
|
Past looting of some shallow sites, natural deterioration of all sites contribute to declining integrity; integrity of deeper wrecks is unknown, but some accidental fouling by fishing gear may have occurred. |
The diminished condition of selected archaeological resources has reduced, to some extent, their historical, scientific or educational value and may affect the eligibility of some sites for listing in the National Register of Historic Places. |
16. |
Threat to Environment |
|
Sites just outside sanctuary boundaries pose a greater threat from leaching chemicals such as bunker fuels and cargos. |
Selected maritime archaeological resources may pose isolated or limited environmental threats, but substantial or persistent impacts are not expected. |
17. |
Human Activities |
|
Impacts to maritime archaeological resources may result from site looting, injury by divers, and vessel activity. Increases in education, enforcement, and trawling closures may allow for improvement. |
Selected activities have resulted in measurable impacts to maritime archaeological resources, but evidence suggests effects are localized, not widespread. |