Research and Monitoring

      

Sanctuary Currents 2001 Fishing for Our Future General Info & Program | Session Abstracts | Ricketts Lecture | MBNMS Awards | Exhibitors Poster Abstracts & Awards | 2001 Symposium Poster (PDF)

Poster Session: Abstracts & Awards

 

Poster Awards

The MBNMS presents awards for outstanding research posters presented at the MBNMS Sanctuary Currents Symposium. The judges determine the specific kinds of awards to present each year based on the posters presented at the Symposium.

Past Research Poster Award Winners

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2001 Best Overall Poster

Bretz, Carrie, Rikk Kvitek, Kate Thomas, and Finnegan Barry

California State University Monterey Bay

Influence of Harmful Algal Blooms on the Foraging Behavior of Shorebirds in Central California

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2001 Best Thematic Poster

Weise, Michael J., and James T. Harvey

Moss Landing Marine Laboratories

California Sea Lion (Zalophus californianus) Abundance, Food Habits, and Impacts on Salmonid Fisheries in Monterey Bay, California During 1997, 1998, and 1999

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2001 Best Student Poster

Gray, Hannah

Morro Bay High School

Investigation of the Biofiltration Potential of the Pacific Oyster (Crassostrea gigas) to Decrease Fecal Coliform Bacterial Levels

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Poster Session Abstracts

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Ammann, Arnold J.

University of California at Santa Cruz

Experimental Evaluation of Standard Monitoring Units for Recruitment of Fishes

Variability in recruitment of juveniles can determine adult population size in some marine reef fishes. Therefore accurate estimates of recruitment can help explain and predict the dynamics and distribution of adult populations. I tested a method for estimating recruitment of temperate reef fish in Monterey Bay, California. This method was standardized for settlement habitat, replicated in space and time, and designed to reduce sampling effort and be cost effective. These standard monitoring units for recruitment of fishes (SMURFs) were constructed of plastic mesh material 1.3m long and 0.3m in diameter. Many fish species settled to SMURFs including cabezon (Scorpaenichthys marmoratus), snailfish (Laparis spp.), and many rockfishes (Sebastes). Two aspects of sampling protocol that may affect estimates of recruitment are depth placement and sampling interval. More fish were found on SMURFs placed at shallow depth (1m below surface) than at mid-water (8m above bottom) and at bottom (1m above bottom) for most species. Recruitment for most species was significantly higher for SMURFs sampled at short intervals (1.7 days) compared to longer sampling intervals (7 and 28 days), although for other species (Sebastes melanops, S. flavidus, and S. serranoides) recruitment was not significantly different between the sampling intervals tested. These results suggest that SMURFs are an efficient and cost effective method and that near surface deployed units are sufficient for estimating recruitment of some temperate reef fish.

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Radiometric Age Validation of The Bocaccio Rockfish, Sebastes paucispinis.

Recent and historic longevity estimates for the bocaccio rockfish, Sebastes paucispinis, range from less than 20 yr to greater than 50 yr based on a variety of traditional ageing techniques (scales, otolith surface ageing, break and burn and transverse sectioning). Otoliths of bocaccio are difficult to read using these techniques and attempts to validate the periodicity of annulus formation have been unsuccessful using marginal increment analysis and oxytetracycline. Because the growth structure of otoliths suggest the bocaccio is long-lived, age was determined using the radioactive disequilibria of lead-210 and radium-226 in otolith cores of adult bocaccio. A combination of age estimates from break-and-burn and otolith weight as a proxy for age were used to place fish into age groups. In some cases radiometric age agreed with the estimates and others did not. Based on radiometric results bocaccio can live at least 24 years and may approach 37 years.

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Age and Growth of a Deep-Sea, Habitat-Forming Octocorallian (Primnoa sp.) from the Gulf of Alaska, with Radiometric Age Validation.

Two nearly complete colonies of red tree coral (Primnoa sp.) collected from off southeast Alaska were provided for an analysis of age and growth characteristics. Growth zones were identified throughout the wood-like skeletal structure (gorgonin) and in the heavily calcified (marble-like) accretion found near the base of large colonies. Growth zones in the calcified region were made visible by thin sectioning and viewed through a dissecting microscope with transmitted light. The calcified base of the complete colonies terminated in a very large knob-shaped accretion. To view the growth pattern within the knob-shaped base without cutting, a CT scan was performed on the two colonies. The views created by these scans were spectacular and revealed that colonies consisted of multiple settlement events, where older basal structures provide for settlement of new colonies. A full limb from one colony was analyzed by taking several sections over the full length of the limb. At each sampling point, thin sections were cut to estimate age from growth zone counts. Contiguous to each section, a 3 to 6 cm piece was cut for radiometric age determination. Cores that appeared to be the first year's growth were extracted from these sections. Because exogenous 210Pb was present, the decay of 210Pb over the length of the colony was used to validate age estimates from growth zone counts. Preliminary results indicated the growth zones identified in sections were formed annually. Age estimates were as high as 89 yr for sections just above the heavily calcified base. Based on validated growth zone counts, growth of red tree coral ranged from 1.8 to 2.1 cm per year in height and was approximately 0.4 mm in radius per year.

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Influence of Harmful Algal Blooms on the Foraging Behavior of Shorebirds in Central California

We tested the general hypothesis that the foraging behavior and distribution of shorebirds under natural conditions are mediated by benthic prey toxicity due to harmful algal blooms (HAB's). In California, observed changes in shorebird (mainly Oystercatchers, Willets, Godwits and Whimbrels) feeding behavior was correlated with seasonal changes in paralytic shellfish poisoning toxins in their primary prey, sea mussels (Mytilus californianus) and mole crabs (Emerita analoga). In rocky habitats where mussel toxicity exceeded 150mgSTX/ 100g, Oystercatchers significantly increased their consumption of limpets as well as their discard rate of mussel tissue. In sandy beach habitats where Emerita toxicity exceeded 150mgSTX/ 100g, shorebird abundance decreased significantly, while their rejection rate of Emerita prey increased significantly.

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Variability in Growth Rates of Juvenile Flatfishes in Estuarine and Coastal Juvenile Habitats

Estuaries are considered vital nursery grounds compared to other juvenile habitats because juvenile fishes presumably benefit from higher growth rates, which can diminish susceptibility to size-selective predators. To determine if juvenile fish experience variable growth rates in different habitats, I conducted caging experiments with 2 species of flatfish (English sole Pleuronectes vetulus and speckled sanddab Citharichthys stigmaeus) in two habitats in central California; mudflats in Elkhorn Slough and subtidal sandflats in Monterey Bay. For both species, growth was higher in the estuary and than on the coast. However, this difference in growth rates decreased with increasing initial fish size suggesting that the benefits of estuarine living diminishes for larger individuals. This pattern is consistent with the migration of larger juveniles from the estuary to the Bay throughout the summer.

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Fisheries Monitoring at San Francisco's Southwest Ocean Outfall: the Evolution of a Regional Monitoring Program

As a compliance requirement of the Oceanside Water Pollution Control Plant National Pollutant Discharge Elimination System (NPDES) permit, the City & County of San Francisco conducts a marine monitoring program in the vicinity of the Southwest Ocean Outfall (SWOO), located 3.75 miles offshore of Ocean Beach. This monitoring program is designed to evaluate impacts from the SWOO wastewater discharge on marine sediments and indigenous marine fauna. This poster describes the evolution of fisheries monitoring, from pre-discharge studies in the early 1980's, to various site-specific post-discharge monitoring plans, and finally to the regional monitoring program begun in 1997. Long-term trend analyses and seasonal variability data are presented to illustrate the need for changes in sample design. The regional monitoring program reduced the sampling frequency to one annual event, which eliminated the effects of seasonality in the data. The study area was greatly expanded to include more reference sites, which increased the statistical power to detect differences between sites due to effects from the SWOO discharge. This design allows the opportunity to better characterize reference conditions in the study area, provides information on impacts from San Francisco Bay outflow, and provides environmental data that can be used in the management of the Monterey Bay National Marine Sanctuary.

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Internship on Behavioral Studies of Harbor Seal Foraging

The focus of this internship was the forging behavior of harbor seal yearlings in the Monterey Bay Marine Sanctuary. I assisted a graduate student in Marine Biology who was conducting the research. To monitor the behavior of the seals they had tracked with radio transmitters on their backs. The seals were captured with nets, tagged, data collected, and then released. After tagging they were tracked with a radio receiver and data on diving behavior was recorded. The data was then analyzed to understand their forging behavior.

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Emerita analoga (Stimpson) - Possible New Indicator Species for the Phycotoxin Domoic Acid in California Coastal Waters

In recent years unexpected occurrences of harmful algal bloom (HABs) events involving the neurotoxin domoic acid (DA) have been documented along the west coast of North America. Blooms of DA synthesizing diatoms (Pseudo-nitzschia sp.) have been associated with the death and injury of hundreds of marine birds and mammals, posed serious health risks to humans, and threatened to significantly impact coastal fisheries and economies dependent on marine resources. Unlike paralytic shellfish poisoning (PSP) toxins, also common on the west coast, a reliable intertidal indicator species for monitoring DA remains to be identified. Here we evaluate and confirm the utility of the common sand crab (Emerita analoga) as an indicator for DA in comparison with sea mussels (Mytilus californianus), the standard bivalve indicator currently used by the California Department of Health Services Shellfish Program for HAB toxin monitoring. Mussels and Emerita from natural populations at two state beaches in Santa Cruz, California (Apr. 1999 - Feb. 2000) were tested for DA using the HPLC-UV method. Toxin loads in Emerita ranged from 0.07 to 10.4 ug DA g-1 and coincided with observed trends in densities of DA producing Pseudo-nitzschia species nearshore. Domoic acid was not detected in any of the mussel samples collected during the study period. The rise and fall of DA in Emerita in synchrony with Pseudo-nitzschia abundance, combined with this common intertidal species accessibility and ease of DA extraction, recommends Emerita as a reliable, cost effective monitoring tool for DA in the coastal environment.

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The Physical Characteristics of Bottom Sediments near Sur Ridge, California, and their Implications in Acoustic Tomography

A study was conducted to determine the relationships between the geomorphology, sedimentology, and acoustics surrounding Sur Ridge, California, and their effects on acoustic tomography. Eleven gravity cores were taken in the vicinity of Sur Ridge. Detailed acoustic and sedimentologial analyses were conducted on the sediments within each core. The results of the acoustic and sedimentological analyses were related to each other, as well as the structural geology, sedimentology, geomorphology, and oceanography surrounding Sur Ridge. The acoustic characteristics of the sediments and the geomorphology of Sur Slope were then examined to determine their impact on the arrival times and structures of acoustic tomography signals sent from Davidson Seamount to Sur Ridge. Sediments along the western slope of Sur Ridge were composed primarily of hemipelagic silty clays. Sediments within the trough to the east of Sur Ridge were composed primarily of evolved relict glauconite grains that appear to be a lag deposit created by a relatively strong bottom current. Analysis of computer-generated acoustic model runs using the in-situ acoustic characteristics of the sediments along the lower portion of Sur slope revealed that both the arrival time and structure of acoustic arrays were significantly impacted by the interaction with the sediment, as well as the geomorphology of Sur slope.

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Why are Geniculate Coralline Algae Rare on Walls in Monterey Bay Kelp Forests?

Geniculate coralline algae such as Calliarthron sp. are usually more abundant on reef platforms than on walls in kelp forest habitats. What causes this difference? Sampling showed that the cover of geniculate coralline algae was significantly greater on reef platforms than on adjacent walls at Monastery Beach, Lover's Point, and Stillwater Cove in central California. Likewise, Calliarthron sp. frond densities were significantly greater on platforms than on walls in Stillwater Cove. I compared Calliarthron sp. settlement and growth on horizontally and vertically-oriented artificial substrates that were attached to subtidal platforms and walls. Post-settlement densities were significantly lower on vertical substrates than on horizontal substrates, suggesting that Calliarthron sp. does not settle successfully on vertical surfaces. Growth rates, percent cover, and frond densities of Calliarthron sp. were significantly greater on horizontal substrates on the platforms than on vertical substrates on the walls. Light measurements and manipulations with barnacle settlement suggest that reduced light levels reaching wall habitats and overgrowth by barnacles and other sessile organisms affect Calliarthron sp. growth on subtidal walls.

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Investigation of the Biofiltration Potential of the Pacific Oyster (Crassostrea gigas) to Decrease Fecal Coliform Bacterial Levels

Previous studies have shown bivalves including Crassostrea gigas to be capable of filtering particles out of the water column, indicating that C. gigas could potentially function as a biofilter for water pollution such as fecal coliforms. To test this, two tanks were used: one with oysters and one without. Escherichia coli was added to both tanks and bacterial concentration decline rates were recorded. In all three repetitions, bacterial concentrations in the tank with oysters declined faster than the tank without. Decreased concentrations in the oyster tank were likely due to the filtering of E. coli by C. gigas. Results of this study substantiate the need and viability of further exploration into the possible use of C. gigas as a biofilter for fecal coliform contaminates.

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Monitoring Surf Zone Dredge Disposal of Fine-Grained Sediments:Santa Cruz Small Craft Harbor, Ca

The Santa Cruz Small Craft Harbor located in the northern part of Monterey Bay suffers sediment accumulation from two separate sources. The harbor entrance collects sand from littoral drift, and the upper harbor accumulates multi-grained sediments after rains from the Arana Gulch Watershed. Due to the presence of silts and muds in the upper harbor sediments, it is not acceptable by State and Federal regulations for this material to be dredged into the surf zone. Other methods of relieving the harbor of this material (by barge or by truck) are very time consuming and costly. The Santa Cruz Port District would like an opportunity to demonstrate that the upper harbor material is suitable for surf zone disposal, in the same manner that the entrance material is. Moss Landing Marine Laboratories will monitor the dredging demonstration event. The monitoring program consists of three phases: Pre-demonstration, During demonstration, and Post-demonstration. A variety of scientific tools and methods will be used to study sedimentary changes that may or may not occur during the demonstration. High-resolution side-scan sonar and multibeam bathymetry data will be collected during the Pre- and Post-demonstration phases as well as comprehensive onshore and offshore sediment and water sampling from Point Santa Cruz to Soquel Point. The Demonstration phase will consist of daily sediment and water sampling events on and offshore at designated high priority locations due to the proximity of the demonstration outfall. Sediment samples will be analyzed for grain size characteristics and water samples will be tested for level of turbidity. Oceanographic data regarding tide, swell direction, height, and period will be collected and analyzed throughout the Demonstration Event, slated to begin in March 2001.

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Differences in Otolith Microstructure Between Hatchery and Wild California Central Valley Chinook Salmon

One challenge in understanding population dynamics of the California Central Valley chinook salmon, (Oncorhynchus tshawytscha), is determining the relative contributions of hatchery and natural sources to the adult ocean population. Current tagging methods, which tag a proportion of hatchery fish, provide limited information on the origin of individuals or the status of wild populations. This study examines the daily deposition of the calcium carbonate matrix of otoliths, fish earstones, as a method for distinguishing hatchery and non-hatchery juveniles in the Central Valley. Differences in otoltih banding patterns from juveniles collected in 1999 originating from 4 hatcheries and 4 rivers allowed for discrimination between the two production sources. Hatchery fish exhibited faster growth rates, as reflected in the wider banding increments and circularity of otoliths than non-hatchery fish. Similarly, hatchery fish showed less variation in daily growth rates, as reflected in a more regular banding pattern of the otolith. The more constant feeding environment in the hatcheries may be responsible for the faster and less variable growth of the hatchery fish. The classification matrix developed using differences in average increment widths, increment variation, and otolith circularity allowed correct classification of 100 % of hatchery fish and 89 % of wild individuals. The robustness of the classification matrix will be further evaluated with samples containing known hatchery fish not used in developing the matrix and known hatchery and wild fish from different year classes. Otolith microstructure may be a useful method in identifying the production sources of individuals collected in the common marine environment, which would aid in studying the dynamics of salmon in the ocean fishery.

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The California Legless Lizard: Microhabitats and Underground Biotelemetry

Microhabitat utilization and home range of the fossorial legless lizard (Anniella pulchra) were studied in 4 hectares of sand dune in central California. Methods were developed using Passive Integrated Transponders (PIT-tags) and underground biotelemetry to track movements within microhabitats, in response to disturbance, and to determine home range and dispersal ability. This is the most abundant population of A. pulchra known (n = 3,582; 0.228/m^2). Abundance was greater in quality habitat (e.g. near lupine bushes) and with greater soil moisture, but lower in disturbed soils. They were routinely found at temperatures below 20 degrees C, and were active day and night.The average home range was 71 m^2 (std. dev. = 87.2). In the laboratory, Anniella moved underground through a system of persistent burrows and vertically migrated to a depth of 46 cm. PIT-tags were a viable method for tracking legless lizards and could be used with other small fossorial animals.

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The Impact of Native Predators on an Invasive Whelk: Sea Otters and Seashells by the Seashore

The recent expansion of Kellet's whelk (Kelletia kelletii: Buccinidae) into central from southern California added a novel species to kelp forest communities. These whelks act both as important predators of native prey species and as a novel prey resource for native predators (sea otters, crabs, sea stars, octopus, and drilling gastropods). A 4 yr study of permanent shell removal plots at the Hopkins Marine Life Refuge in Monterey Bay identified potential predators of the whelk and determined the types and frequencies of shell damage. Most shell debris consisted of "window" damage (42%), whorls only (25%), or spires only (21%). Feeding trials with captive sea otters demonstrated that otters were capable of producing "window" damage. Shells collected in the field indicate that the process that creates windows can also separate the body whorl and spire. Similar whelk shells in southern California were extremely rare and very old. Thus, the recently established whelk populations in central California are severely impacted by sea otters, which account for nearly 90% of the shells observed in the field. Furthermore, the apparent failure of local reproductive efforts by resident whelks in central California suggests these populations are "sinks" that could become locally extinct. Such an extinction would represent a rare marine example of native predators contributing to the failure of an invader.

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Emerita analoga (Stimpson) as an Indicator Species for Paralytic Shellfish Poisoning Toxins along the California Coast

Paralytic shellfish poisoning toxins (PSPT) pose a serious threat to public health worldwide. Along the west coast of North America, Mytilus californianus has long been used as the primary indicator species for monitoring levels of PSPT in the environment. However, because the distribution of this species is limited to rocky shores, vast stretches of sandy beaches are not monitored for PSPT. This lack of information greatly reduces our ability to track and predict harmful algal bloom development and movement along the west coast of much of North and South America. Early studies on Emerita analoga, a common sandy shore invertebrate of the eastern Pacific, showed that this species can sequester saxitoxin (STX, the primary neurotoxin produced by PSPT blooms) in its tissues. The purpose of this study was to develop a PSPT extraction protocol for E. analoga, and to compare the utility of this species as a PSPT indicator with that of M. californianus. Samples of both species were spiked with known amounts of saxitoxin and processed (M. californianus with the standard acid extraction procedure and E. analoga with the new adapted acid extraction process). Spike and recovery results show that the percentage of STX recovery for E. analoga is 3-9% higher than for M. californianus. To compare the uptake and depuration rates of PSPT for the two species under identical field conditions, samples of each were collected at six pairs of adjacent rocky and sandy beaches, along the central coast of California in 1998 and 1999 from April through November, the season of historically high PSPT. Results from these comparisons showed E. analoga to be a reliable indicator for PSPT HAB events along sandy shores.

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El Niño and La Niña Across the Central California Coastal Upwelling Zone: Physics, Nutrients, and Effects an Phytoplankton

The 1997-1998 El Niño and the 1999-2000 La Niña across the central California upwelling zone are described, and both events are compared to 'normal' conditions observed during 1988-1991.

 El Niño began in summer 1997, peaked in fall and winter of 1997-98, and persisted through spring and summer of 1998. Anomalously warm SSTs, low macronutrient levels, and low chlorophyll and primary production values characterized this event. Biological effects were particularly strong during spring and summer 1998, when development of the coastal upwelling regime was constrained to a narrow band nearshore.

Immediately following the El Niño, La Niña began in Fall 1998 and persists to the present. Features of this event are low SSTs, high macronutrient levels, and high chlorophyll and primary production values. The coastal upwelling regime and its high rates of biological production have been well developed as a broad band offshore.

These oceanographic fluctuations are related to larger-scale and longer-term climate and ocean variability. The variations in primary production likely have strong effects on zooplankton, fish and higher trophic levels.

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The Effects of Sea Surface Temperature on Fisheries in the Monterey Bay

Economic concerns have increased due to the devastating effects of El Niño Southern Oscillation (ENSO) climatic fluctuations on global fisheries. Various fisheries in the Monterey Bay were analyzed to determine if a correlation exists between fishery catch/effort and sea surface temperature (SSTA) from 1981-1997. Since 1989, the squid, rockfish, mackerel, anchovy, salmon, swordfish, and sablefish fisheries have been the most important in terms of pounds landed and dollar value at Monterey, Santa Cruz, Pillar Point, and Moss Landing ports. The fishery data included: catch, revenue, price, and effort for various fisheries from 1981-1997. Linear regressions using fishery data and sea surface temperature were performed to determine if any correlation existed. Most of the catch and revenue for each fishery declined over the sixteen-year time period, while the price per pound steadily increased. By predicting how a climatic fluctuation event could affect a fishery, economic hardships can be lessened and even sometimes avoided.

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Marine Debris

Imagine a street never cleaned of its litter. Then imagine 20 to 50 feet of water on top of it and you have an idea of what marine life is like under a wharf.

Although protected from dumping the Monterey Bay Sanctuary has accumulated garbage. This garbage is called Marine Debris and it is killing wildlife.

Marine Debris begins its life on land, usually as convenient, consumer product packaging. In the past this debris was dumped far out at sea by ships disposing of their garbage along with sewage (dunnage). Most marine debris originates on shore and is blown or dropped into streets or into waterways eventually finding its way to the ocean, it is also dropped directly into the ocean from wharves. Either way the debris is deadly to marine life and causes suffering to animals while further stressing the entire marine ecosystem.

According to estimates by the California Coastal Commission there are over "46,000 pieces of plastic debris floating on every square mile of ocean." Of all of the marine debris in the ocean 90% is plastic.

Three-quarters of the surface of our earth is covered in ocean and the problem of marine debris has reached global proportions. No area of our planet has been untouched. Most debris enters the ocean near coastal cities where it travels to sea and stacks up along current drift lines or washes back up on our shores. Currents carry debris thousands of miles.

This poster presentation is intended to educate the public on the issue of Marine Debris and its effects on our ecosystem.

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Our World

Conservation and moderation is proving essential for the health of our planet and also for the health of humankind. With 300 miles of the Central Coast directly affecting the Monterey Bay waters and the world's oceans. It is everyone's responsibility not to litter, pollute, destroy, or be greedy with the Earth's natural resources. The Citizen Watershed Monitoring Network and Sustainable Seas Explorations are just two of the many organizations that work with The Center For Marine Conservation. They work to find solutions and create plans that will keep our waters clean, healthy, and oxygenated. On and off-shore it is all humans who have the planet Earth to thank and to protect.

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Impacts of Dispersal and Foraging Location on the Survivorship of Pacific Harbor Seal (Phoca vitulina richardsi) Juveniles in Central California

Despite numerous studies of Pacific harbor seal (Phoca vitulina richardsi) in central California, few have focused on factors impacting survivorship of juvenile seals. We hypothesized that weaned pups would travel greater distances in search of potential foraging locations, whereas, more experienced yearlings would exhibit localized movements similar to those of adult seals. We also predicted that juvenile seals foraging in productive nearshore areas would have greater survivorship rates than those foraging in less productive areas. Ten weaned harbor seal pups and four yearlings were captured in 2000 and outfitted with VHF radio transmitters at principle haul-out sites in or near Monterey Bay and Point Reyes, California. Aerial surveys were conducted from Fort Bragg to Point Sur to determine maximum distance traveled and to estimate foraging locations of seals. Maximum distances dispersed ranged from 12 to 350 km for Monterey pups and 12 to 65 km for Point Reyes pups. All Monterey pups dispersed northward, possibly following food sources in the California Current System. Three remained in Monterey Bay and one traveled as far as Mendocino. Three of the five Point Reyes pups dispersed to Point Reyes Headlands, a site of intense upwelling, whereas one of the pups traveled south to Bolinas Lagoon, and another to Half Moon Bay. Two of the four yearlings remained at the site they were tagged and occasionally traveled short distances (25 km) to alternate haul-out sites or foraging areas. One yearling, however, remained at the capture site approximately one month, then traveled 65 km to Cooper Point, just south of Point Sur. In August 2000, three months after weaning, survivorship was 90% (9 out of 10 pups). Observed dispersal to productive areas may have increased the survival of these pups.

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Monitoring the Sanctuary's Rocky Intertidal: A High School and Volunteer Program at the Seymour Marine Discovery Center

We are developing site-specific protocols for long-term monitoring of the rocky intertidal of central California to be used by high school students and other volunteers. Current high schools involved are Aptos, Harbor, Watsonville, and Monterey. Counts of prominent species in random quadrats within permanent plots at Natural Bridges continue a monitoring program begun in 1972. Vertical transects at Natural Bridges, Soquel Point, and Point Pinos establish zonation patterns that will change if sea level changes. Abundance and sizes of important species (e.g., owl limpets and sea stars) at all three sites will detect recruitment and mortality patterns. An interactive website with the data will be maintained by the Seymour Marine Discovery Center. Data collected to date at Natural Bridges compare favorably with those collected by professional researchers, giving us confidence that the program will not only introduce students to the rich biota of the rocky intertidal and how to study it, but will provide data that can be used by scientists and resource managers to track long-term changes in this spectacular habitat. Supported by California Sea Grant and the Monterey Bay National Marine Sanctuary.

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Fishing Capacity in the Squid Fishery: Past, Present and Prospective

As part of the California Department of Fish and Game's (DFG) efforts to draft its first fishery management plan for squid, it must establish a "capacity goal" and propose mechanisms such as limited entry for achieving that goal. DFG has tackled this difficult task by analyzing squid landings data, as reflected in its recently released fishery management options. DFG recommends an annual landings cap of 125,000 metric tons (mt) for the fishery, and outlines six fleet configurations that would achieve the fleet capacity goal expected to meet, but not exceed, that landings cap. Each configuration reflects the results of applying certain assumptions about fishing intensity and specialization of vessels in the fleet. Qualifying criteria (for a limited entry permit) that would create these configurations are also provided. Using landings and interview data, we explore the concepts of harvesting capacity and capacity utilization in the squid fishery, and its implications for management. Through exploratory analysis of this information, we consider the fleet's activities in other fisheries, the relative importance of squid, and other factors that may influence capacity and its use under limited entry. Results focus on the fleet as a whole, but include particular attention to the Monterey fleet.

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Northeast Pacific Climate Change Mechanisms

We are investigating mechanisms of climate change in the northeast Pacific (NEP) relevant to variations in marine ecosystems, especially fishery populations. In this research, we are synthesizing and analyzing extensive historical oceanic and atmospheric data sets. Our work uses global, high-resolution, ocean models to simulate processes not adequately represented in observations (see Ocean Model box). We also are using atmospheric models to identify atmospheric processes that lead to climate change in the NEP.

Seasonal cycles of key observed and modeled ocean fields are being related to atmospheric forcing fields, and compared with the mechanisms of interannual and decadal variations, with emphasis on major interannual (e.g., El Niño and La Niña) events, and possible decadal regime shifts around 1990 and 1998. We are comparing basin scale and regional changes to see if similar mechanisms operate at these different spatial scales. From these analyses, biologically relevant indices of climate change are being developed.

The observational and model products we are developing cover a wide range of environmental data sets and indices that define climate change in the NEP and its ecosystem effects. These products are being delivered through the web, principally via the PFEL live access server site: http://salmonid.pfeg.noaa.gov/las.html.

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Evidence of Chemical Cueing for Larval Release in the Solitary Orange Cup Coral, Balanophyllia elegans.

Solitary orange cup corals (Balanophyllia elegans) were collected from Breakwater Cove, Monterey in February and August of 1998. Individual corals were assigned to either an "isolated" (separate containers with individual water supplies) or "grouped" (combined in one container with a common water supply) treatment in September 1998 and monthly larval production was measured from October 1998 to the present. During the first two years of the experiment, the isolated corals released significantly fewer larvae per capita than those that were grouped. However, in June of 2000 I placed all females from the isolated treatment into a common container, which maintained their isolation from the males, but effectively grouped them in their living conditions. Now in the third year of the study, these previously isolated females are releasing equivalent numbers of larvae as the corals in the grouped treatment. This suggests that a chemical cue from neighboring corals may significantly enhance larval release, and I outline an experiment to test for such cueing.

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California Sea Lion (Zalophus californianus) Abundance, Food Habits, and Impacts on Salmonid Fisheries in Monterey Bay, California During 1997, 1998, and 1999

To assess competition between commercial fisheries and California sea lion (Zalophus californianus) in Monterey Bay, California I estimated sea lion seasonal abundance, seasonal food habits, annual fish consumption, and percentages of hooked fish taken by sea lions in commercial and recreational salmon fisheries during 1997 to 1999. Aerial and ground surveys during 1997 and 1998 indicated that seasonal trends in sea lion numbers on haul-out sites corresponded with their annual migration, with greater numbers of animals in the region in summer and fall 1998. Prey hard parts identified in sea lion fecal samples (n=503) indicated that sea lions consumed mostly schooling species such as market squid (Loligo opalescens), Pacific sardine (Sardinops caeruleus), northern anchovy (Engraulis mordax), and spiny dogfish sharks (Squalis acanthias). Significant changes in prey composition were observed in summer and autumn 1998 most likely as a result of shifts in prey distribution in response to the 1997-1998 El Niño Southern Oscillation event. In 1998, California sea lions consumed annually an estimated 269.1 to 804.7 metric tons (mt) of salmon, 988.4 to 2,206.8 mt of sardine, and 533.4 to 1,827.4 mt of rockfishes. Sea lions took 8.5 % (1997), 28.6% (1998), and 8.9% (1999) of fish hooked in the commercial fishery, 8.4 % (1997), 18.3 % (1998), and 2.2% (1999) of fish hooked in the Commercial Passenger Fishing Vessel fishery, and 15.6 % (1997), 17.5 % (1998), and 4.0% (1999) of fish hooked in the skiff fishery. Hooked salmon from the fisheries are likely the majority of salmon in the diet of sea lions. Assessing the impact of sea lions and other natural predators on prey populations is difficult, but necessary for effective fisheries management.

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Night Moves - Pinniped Predation of Winter-Run Steelhead (Oncorhynchus mykiss) in the San Lorenzo River During 1998 to 2000

Increasing pinniped populations have caused concern that predation on salmonids by pinnipeds could be increasing and possibly affecting the recovery of listed salmonid populations. The San Lorenzo River has the largest run of federally listed winter-run steelhead in the Monterey Bay region with approximately 2,500 steelhead, and has the greatest co-occurrence of pinnipeds in and near the river mouth. Harbor seal (Phoca vitulina richardsi) foraging behavior was monitored during daytime hours from January to April 1998 and 1999, and during nighttime hours in 2000. No predation events were observed in 1998, and six predation events, one of which involved a steelhead, were observed in 1999. During nighttime hours in 2000, approximately 57 predation events were observed, including 18 steelhead, 35 lamprey, and four unidentified prey species. Estimates of total predation on steelhead ranged from approximately 111 to 177 fish during the 2000 winter run. Impacts on winter-run steelhead were difficult to assess because total run size estimates for the San Lorenzo River during 2000 were not available at the time of this poster. Pinniped tooth and claw marks were identified on 28.3% of the steelhead in 1998, 33.3% of the fish in 1999, and 36.6% of the 560 winter-run steelhead that passed upstream through the fish trap in 2000. Information on food habits of harbor seals in the Monterey Bay region was obtained through the examination and identification of prey hard parts found in fecal samples. Bottom fishes and schooling fishes were the most commonly occurring fish species, such as northern anchovy (Engraulis mordax; 25.4%), Dover sole (Microstomus pacificus; 25.0), rockfishes (Sebastes sp.; 24.9%), octopus (Octopus sp.;21.3%), and English sole (Pleuronectes vetulus; 20.5%; Table 1). Salmonid otoliths occurred only twice in our fecal samples in 1998 and 2000, but further analysis of all prey hard parts may show that salmon are consumed and may represent a larger portion of the biomass consumed.