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  • A quantitative ecological study of selected nearshore marine plants and animals at the Diablo Canyon power plant site: a pre-operational baseline, 1973-1978

    Gotshall, Daniel W.; Laurent, Laurence L.; Owen, Sandra L.; Grant, John J.; Law, Philip (California Department of Fish and Game, 1984)
    Biologists of the California Department of Fish and Game, under contract with the Pacific Gas and Electric Company, conducted surveys or intertidal and subtidal plants and animals 1n the vicinity of the Diablo Canyon Nuclear PowerPlant for the summer of 1973 through 1978. Abundances of the dominant plants and animals were obtained at random as well as permanent stations in Diablo Cove as well as nearby control areas. A total of 643 permanent and random stations were surveyed, 262 in the intertidal and 381 in the subtidal.Natural as well as man-caused occurrences have resulted in several significant changes in plant and animal abundance in the study areas; these include the arrival of the southern front or the sea otter population in Diablo Cove in 1974; a strong red tide bloom in the fall of 1974; and the release of copper ions from the power plant condenser tubes into Diablo Cove during the summer of 1974.Our intertidal and subtidal random station data have shown a strong decline in giant red sea urchin, Strongylocentrotus franciscanus, densities and the surface canopy kelp, Nereocystis/leutkeana, and a corresponding increase in thesubcanopy kelps, Pterygophora and Laminaria. Seasonal patterns of abundance of foliose red algae at random intertidal stations occurred at all study areas. Several species intertidal and subtidal invertebrates showed increasing or decreasing trends in levels of abundance during the five year study period covered by the report. Some of these changes in abundance may be related tothe natural man-caused impacts mentioned above. (Document has 728 pages)
  • Pre-operational baseline studies of selected nearshore marine biota at the Diablo Canyon power plant site: 1979-1982

    Gotshall, Daniel W.; Raymond Ally, J.R.; Vaughan, Douglas L.; Hatfield, Brian B.; Law, Philip (California Department of Fish and Game, 1986)
    This is the final report of the California Department of Fish and Games intertidal and subtidal surveys of plants and animals in the vicinity of the Diablo Canyon Power Plant. These studies cover the period from 1979 through 1982. Our previous report (Gotshall, et al. 1984) covered the period from 1973 through 1978. The report includes abundances and statistical analyses of comparisons of abundances between years and study areas for selected intertidal and subtidal plants and animals. A total of 556 random subtidalstations, 540 intertidal stations and 67 permanent abalone transects were completed during this report period.Trends in abundances of most species observed during our 1973 through 1978 studies continued, i.e. the population of giant red sea urchins remained at a very low level, bull kelp Nereocystis leutkeana densities continued to decline in Diablo Cove and North Control. These two trends are probably due to the effects of continued sea otter foraging in the study area.Our observations of the presence or absence of fishes at subtidal 30m stations indicate a continued decline in the abundances of lingcod, Ophiodon elongatus and a decline in the abundance of blue rockfish since the 1973 through 1978 study period.A new study was begun during this study period, the use of baited stations to obtain relative abundance indices for those species of fishes attracted to the bait. Black-and-yellow rockfish were the most frequently observed fishes at Diablo Cove stations, while blue rockfish were the most frequently observed fish at North control baited stations. (Document has 393 pages)
  • Results of the 1972 skindiving assessment survey, Pismo Beach to Oregon

    Miller, Daniel J.; Geibel, John J.; Houk, James L. (California Department of Fish and Game, 1974)
    A skindiving survey was conducted from January throughDecember 1972 to estimate number of divers, diving days,hourly effort and animals taken from Pismo Beach to Oregon.Comparisons were made with estimates of the 1960 skindivingsurvey. A total of 15,030 divers were interviewed at 33locations from Pismo Beach, San Luis Obispo County, to theOregon border. The number of indiv1dual divers increasedfrom 2,200 in 1960 to 11,800 in 1972. Diving days increasedfrom 37,782 to 95,194. Over 50% of all diving was in theMonterey - Carmel area. Most diving hours were spent intraining, followed by abalone diving, observing, spearfishing, and photography. Totals of 82,174 abalones and 24,089 fishes were taken. Lingcod were the most abundant fish speared followed by blue rockfish and cabezon. Spearfishing dropped significantly in effort since 1960 and training and observing greatly increased. The take of abalones, urchins, crabs, and clams virtually disappeared from Point Estero to Seaside, the foraging range of the sea otter. The number of abalones taken increased outside the sea otter's range. (Document has 63 pages)
  • The mortality rate of Engraulis mordax in Southern California

    MacCall, Alec D. (California Department of Fish and Game, 1973)
    The annual mortality rate for the northern anchovy, Engraulismordax, is estimated to be 66.5% in southern California waters, although the mortality rate increases sharply for older fish. A method for evaluating recruitment regularity and age constancy of mortality is presented. (Document has 25 pages)
  • The Southern California jack mackerel fishery and age, length and sex composition of the catch for the 1967-68 through 1971-72 seasons

    Fleming, Eugene R.; Knaggs, Eric H. (California Department of Fish and Game, 1977)
    Commercial landings for 5 seasons, 1967-68 through1971-72, approximated 36.5, 58.7, 36.8, 57.0 and 56.2million pounds respectively (16,600; 26,600; 16,700;25,900 and 25,500 Mg).The 1967 year class dominated the fishery during the 1967-68 and 1968-69 seasons. The 1970 year class, in the fishery only 2 years, contributed an estimated 250 million fish and 45 million pounds (20,400 Mg). (46pp.)
  • The marine environment in the vicinity of Diablo Cove with special reference to abalones and bony fishes

    Burge, Richard T.; Schultz, Steven A. (California Department of Fish and Game, 1973)
    Diablo Cove, a future warm water discharge site, is located about midpoint of a 13 mile long rocky shoreside reef in central California. The reef, physically isolated from other similar coastal areas, supports important kelp bed communities of nonmigratory vertebrates and invertebratesthat must be constantly monitored to ensure they are protected.This 2 year study is a base line inventory done in the vicinity of Diablo Cove with major emphasis on abalones, including their food chain, and bony fishes. Data was obtained on the life history and annual canopy development of the kelp Nereocystis and all macroalgae were cataloged. Seasonal collections of fishes were made to document thosespecies indigenous to the system and to obtain life history information on the common forms. (Document has 429 pages.)
  • The status of the white seabass resource and its management

    Young, Parke H. (California Department of Fish and Game, 1973)
    White seabass, Cynoscion nobilis, have been fished inCalifornia since late in the ninteenth century. At presentthe commercial fishery is stable, landing about 8 hundredthousand pounds per year, but the sport fishing has declinedto the poorest catch on record. (Document has 11 pages.)
  • The southern California Jack Mackerel fishery, and the age and length composition of the catch for the 1972-73 through 1983-84 seasons

    Mason, Janet E. (California Department of Fish and Game, 1989)
    Jack mackerel landings in southern California during the 1972-73 to 1983-84 seasons indicate successful year classes in 1974, 1976, 1978, and 1980, each contributing over 150 million fish to the fishery. These alternated with weak year classes in 1973, 1975, 1977, 1979, and 1981, each contributing less than 60 million fish. A majority of the fish were caught as one- and two-year-olds and were less than 300 mm in length. (45pp.)
  • The speckled scallop, Argopecten circularis, in Aqua Hedionda Lagoon, San Diego County, California

    Haaker, Peter L.; Duffy, John M.; Henderson, Kristine C.; Parker, David O. (California Department of Fish and Game, 1988)
    Speckled scallops, Argopecten circularis (Sowerby, 1835), were sampled at Agua Hedionda Lagoon, Carlsbad, San Diego County from March 1984 to October 1986, to obtain basic life history data. Monthly samples of scallops were collected, measured, and released to obtain length frequency data for estimates of growth, life span, and spawning period. Subsamples of scallops were collected for determination of gonadal-somatic and adductor muscle-somatic indices.In 1984 large concentrations of speckled scallops were found on the sand-silt bottom of the lagoon, closely associated with eelgrass, Zostra marina. During the course of the study the numbers of scallops declined, until their virtual disappearance at the end of 1986. Monthly length frequency plots from 24,375 scallop measurements indicate that this is a rapidly growing species with a short life span. Gonadal- and adductor muscle-somatic indices from subsamples of 1,714 scallops indicate first spawning at age one and a relationship between temperature and spawning.Based on this study management recommendations are made for the speckled scallop. (39pp.)
  • Deepwater demersal fishes observed from the submersible Avalon (DSRV-2) off the Farallon Islands, 24 June 1985

    Gotshall, Daniel W.; Dyer, Robert S. (California Department of Fish and Game, 1987)
    On 24 June 1985 the U.S. Navy's Deep Submergence RescueVehicle AVALON [DSRV-2] was used to locate low-levelradioactive waste containers and make observations ofdeepwater benthic fishes and invertebrates at the 900 m (2952 ft) radioactive waste disposal site approximat1y 4.4 km SW of the Farallon Islands off San Francisco, California. During the three hours on the bottom in depths of 975 to 1039 m (3198 to 3408 ft) five identifiable species of demersal fishes were observed: Dover sole, Microstomus pacificus; thornyheads, Sebastolobus spp.; deepsea sole, Embassichthys bathybius; sablefish, Anoplopoma fimbria; and Pacific hagfish, Eptatretus stoutii. Unidentifiable demersal fishes from the families Macrouridae and Zoarcidae were alsoobserved. Several species of macroinvertebrates were alsoidentified, including the tanner crab, Chionoecetes tanneri,and a large sea pen, Stylatula elongata. One low-level wastecontainer was located. The biology of the observed fishes and their commercial importance is discussed. (22pp.)
  • A review of the San Diego Bay striped mullet, Mugil Cephalus, fishery

    Duffy, John M. (California Department of Fish and Game, 1987)
    San Diego Bay was reopened to commercial gill net fishingfor striped mullet, Mugil cephalus, in that portion of thebay south of the San Diego - Coronado bridge in 1977 via anexperimental gear permit issued by the Fish and GameCommission. In 1985, legislation was passed allowing up tofive permits each annual season to fish for striped mulletin south San Diego Bay. Annual landings ranged from 18,700to 46,800 pounds from 1980 through 1986. (17pp.)
  • An assessment of the accidental take of sea otters, Enhydra lutris, in gill and trammel nets

    Wendell, Frederick E.; Hardy, Robert A.; Ames, Jack A. (California Department of Fish and Game, 1986)
    The sea otter, Enhydra 1utris, is fully protected inCalifornia by both state and federal law. Despite thisprotection the population has not grown appreciably since atleast 1976. Research efforts directed at identifying thereasons for the lack of population growth have concentratedon sources of mortality and their contribution to totalmortality.The accidental drowning of sea otters in gill and trammelnets used to take California halibut, Para1ichthysca1ifornicus, was identified as a source of mortality whichhas probably increased as the sea otter population expandedinto areas of intense fishing. As a result, an existinggill and trammel net fishery observation program in MontereyBay was expanded to assess the extent and significance ofthe accidental drownings of sea otters in the areas nearMorro Bay and Port San Luis.Three different estimates of the number of sea ottersdrowned annually in gill and trammel nets were generatedusing comparable data bases. The average of these estimateswas approximately 80 sea otters per year for the level offishing effort expended during the June 1982 through June1984 study period.Back calculations of the annual take of sea otters by thegill and trammel net fishery for California halibut weremade for each year from 1973 through 1983. Thesecalculations suggest that the level of accidental take ofsea otters during the last decade may have been high enoughto be a significant factor in the lack of sea otterpopulation growth. (31pp.)
  • Red abalone size data from Johnsons Lee, Santa Rosa Island, collected from 1978 to 1984

    Haaker, Peter L.; Parker, David O.; Henderson, Kristine C. (California Department of Fish and Game, 1986)
    Red abalone, Haliotis rufescens, were collected at Johnsons Lee, Santa Rosa Island, in the summers of 1978 through 1982, and in 1984, to obtain data for determining various fishery population parameters. Annual visits to the study site were made at yearly intervals to simplify growth calculations.During the first four visits, 2145 red abalones were tagged,measured, and replaced. Shell damage, soft tissue injuries, and causes of mortality were noted. The method of tagging isdescribed.Recovery of first tagged abalone after one year was approximately 30%. Analysis of variance of the annual samples indicated that the samples were, with one exception, not different. Summaries are presented of the number of abalone collected and tagged by year, frequencies of shell damage, soft tissue injury, predatory sponge infestation, and total mortality. Appendices include a listing of the raw size data and various codes for each tagged abalone. (56pp.)
  • A simulated translocation of sea otters, Enhydra lutris, with a review of capture, transport and holding techniques

    Ames, Jack A.; Hardy, Robert A.; Wendell, Frederich E. (California Department of Fish and Game, 1986)
    A number of techniques and pieces of equipment judged necessary for the translocation of sea otters were field tested. Captures were accomplished with either a scuba diver operated capture device (Wilson trap), a surface set tangle net or a dip net. A portable floating pen proved verysatisfactory for simultaneously holding at least ten otters for several days. Commercially available pet transport kennels, with the capability of holding water, were adequate for maintaining the otter's pelage in good condition during a transport of approximately five hours duration. Subsequent observations indicated no apparent stress related dispersal. (17pp.)
  • A review of California sea otter, Enhydra lutris, surveys

    Wendell, Fred E.; Hardy, Robert A.; Ames, Jack A. (California Department of Fish and Game, 1986)
    Recent surveys (1977 to 1983) of the sea otter, Enhydra lutris, in California were summarized and compared to past surveys, to evaluate the adequacy of current survey design and to-make inferences about current population status.Ground counts within selected index areas provided the bestindicator of population trends. These data suggest a ratherremarkable stability in the long-term occupied range. Rangewide aerial surveys with ground truth stations provided the best available data for estimating total population size. The most recent (1979) survey yielded a population estimate of approximately 1500 sea otters. Comparisons with past surveys suggest there have been no demonstrable changes in population size since at least 1976. (34pp.)
  • The Northern Anchovy reduction fishery for the 1978-79 through 1981-82 seasons

    Sunada, John S.; Read, Robert B. (California Department of Fish and Game, 1985)
    Nearly 49,000 metric tons (MT) of anchovies were taken during the 1978-79 season, followed by 32,390 MT in 1979-80, 60,678 MT in 1980-81 and 45,150 MT in 1981-82. A total of 14,076 fish was sampled during the four seasons for age, length and sex. The fishery during the four seasons consisted mainly of young-of-the-year and age groups I and II fish. The 1978 and 1979 yr classes comprised the major share of the catch. Seasonal mean lengths varied from 112 mm standard length (SL) in the 1979-80 season to 122 mm SL for the 1981-82 season. Female to male sex ratios ranged from 1.17:l (1978-79 season) to 1.59:l (1979-80 season). (28pp.)
  • A checklist of zooplankters from the Gulf of the Farallones and off Northern California

    Tasto, Robert N.; Mogelberg, Deborah D.; Hatfield, Susan E.; Muller, Roslynn (California Department of Fish and Game, 1981)
    Plankton samples were collected from January through June 1975-80 as part of the Dungeness Crab Research Program. Zooplankters were identified and enumerated from 1975-77 and 1979 samples taken in the Gulf of the Farallones and from 1979 samples off northern California. A checklist of zooplankters found in these samples is presented along with information on location, frequency of occurrence, and density. (57pp.)
  • Ecology of fishes in Upper Newport Bay, California: seasonal dynamics and community structure

    Horn, Michael H.; Allen, Larry G. (California Department of Fish and Game, 1981)
    A total of 366 bimonthly (January 1978-January 1979) samples taken with six types of gear (otter trawl, gill net, bag seine, small seine, drop net, square enclosure - allwith replication except the gill net) at four stations inupper Newport Bay, California yielded 51,816 fishes belonging to 46 species and weighing over 353 kg. Atherinops affinis (topsmelt) was the most abundant species accounting for 76% of total individuals. Seven species, all of low trophic levels, made up over 97% of the total catch. Mugil cephalus (striped mullet) ranked first in biomass (= 36% of the total) with six species accounting for more than 80% of the total biomass. The largest number of individuals (71%) was collected with the bag seine, the greatest number of species (35) was captured with the otter trawl and the largest percentage of the biomass (56%)was obtained with the gill net. Species richness, number of individuals and biomass were lowest in January (1978 or 1979) or March and highest in July (numbers, biomass) or September (species). Bimonthly diversity (H') values ranged from 0.48 to 2.17 (overall value 1.05) and tended to be inversely related to abundance levels. Species richness was greatest at Station 4 (the lowermost station) and least at Station 1 (the uppermost station). Numbers of individuals and biomass peaked at Station 2 and reached lowest levels at Station 1.Length-frequency analysis of six of the most abundantspecies indicated utilization of the upper bay by two ormore stages in the life history of these species.More than 92,000 eggs belonging to seven taxa and anunknown category and 426 larvae from 20 taxa were collectedwith a 0.5 m net mounted on an epibenthic sled during thesame bimonthly periods and at the same stations as thejuvenile/adult samples. Most of the eggs were collected atStation 2 in May with the numbers overwhelmingly dominatedby those of Anchoa compressa (deepbody anchovy) (99.7% oftotal numbers). The most abundant larva was that ofClevelandia ios (arrow goby). Nearly 60% of the totallarval catch was made up of members of the family Gobiidae.Larval taxa and individuals were fewest in January (1978).The number of taxa was highest in March, September andJanuary (1979) whereas larval numbers peaked in May. Thenumber of taxa and of individual larvae varied only slightlyamong the four stations.Asymptotic species accumulation curves indicated adequate sampling of juvenile/adult fishes. Cluster analysisproduced eight species groups of resident and periodicspecies that variously utilize the three main habitats(channel, inshore, pannes) in the upper bay. Speciesrichness and abundance were positively correlated with bothtemperature and salinity. Temperature, salinity and depthof capture were frequently correlated with individual species abundances and were used in combination to partially explain the spatial utilization of species and species groups.The upper bay fish community is important and worthy ofpreservation for at least three reasons: 1) it containsspecies assemblages not duplicated in any other coastalenvironment; 2) it contains life history stages of avariety of coastal fish species; and 3) it contains largepopulations of small, low-trophic level species and juveniles of other species which serve as forage for larger, predatory species that are frequently of economic importance. Members of the fish community respond noticeably to altered environmental conditions such as the heavy rainfall (and accompanying low salinity and high turbidity) that occurred during the early months of 1978. The short and long term, as yet often unpredictable, fluctuations in the populations emphasize the need for periodic monitoring and for the development of a mathematical model of the fish community if it is to be thoroughly understood and properly managed. (102pp.)
  • Structure, distribution, and seasonal dynamics of the benthic community in the upper Newport Bay, California

    Seapy, Roger R. (California Department of Fish and Game, 1981)
    The benthic community in the Upper Newport Bay was sampledat two intertidal and two subtidal depths at three stationsduring five assessment periods between October 1977 and January 1979. Heavy sediment deposition occurred during the 1977-1978 winter period, and the sedimentary environment was transformed from one characterized by fine sands (January 1978) to one dominated by silts (January 1979). Total density, species richness, and species diversity were generally lowest at the uppermost station (Ski Zone) and highest at the lowermost station (Shellmaker Island). Immediately following the 1977-1978 winter rainy period, total faunal density was extremely low, particularlyat the Ski Zone station. However, heavy recruitment after April 1978 resulted in maximal total density values at all stations in August 1978. Species richness was highest during October 1977 and lowest in April 1978 following the heavy rainfall period. The benthic community was dominated in October 1977 by three polychaetes, Fabricia limnicola, Streblospio benedicti, and Capitella capitata. By August 1978, F. limnicola had not recruited back into the community and three additiona1 polychaete species (Polydora ligni, Pseudopolydora paucibranchiata, and Scolelepis acuta) shared community dominance with C. capitata and S. benedicti. The crustaceans showed strong seasonal oscillations, being abundant in the October and August samples and occurringsparsely in the January and April samples. (76pp.)
  • The anchovy reduction fishery for the 1977-78 season

    Sunada, John S. (California Department of Fish and Game, 1979)
    Landings for the 1977-78 season were 62,118 metric tons(68,476 tons) in southern California and 6,541 metric tons (7,212 tons) in central California. The southern area's samples were characterized by the dominance of the 1976 year class (38%) while central California data indicated the 1977 year class (38%) as the most abundant year class. Sex ratios indicated a near 1:1 ratio for both southern and central California. (24pp.)

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