Mary M. Yoklavich

Mary M. Yoklavich
Moss Landing Marine Labs | MLML · Fish Ecology

About

91
Publications
14,393
Reads
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3,693
Citations
Introduction
I am a marine biologist and ecologist, conducting surveys of fishes, corals, and seafloor habitats in deep water using manned submersibles, remotely operated vehicles (ROV), and autonomous underwater vehicles (AUV). My research has led to insights into the importance of marine habitats to fishes, the role of cold-water corals in deepsea communities, the magnitude and impact of marine debris, and the siting and effectiveness of MPAs for fishery and habitat conservation.
Additional affiliations
January 1991 - December 2017
National Marine Fisheries Service
Position
  • Researcher
Description
  • Retired, 12/31/17

Publications

Publications (91)
Article
During the period 1992–2014, we quantified 79,233 deep-sea corals (DSC; azooxanthellate corals occurring in cold or deep waters, generally >50 m) at depths 23–867 m from 1281 visual transects in areas of rocky substrata off northern, central, and southern California. DSC were present on 68% of transects at all depths and substrata types. Thirty-nin...
Article
Full-text available
Fishes are known to use deep-sea coral and sponge (DSCS) species as habitat, but it is uncertain whether this relationship is facultative (circumstantial and not restricted to a particular function) or obligate (necessary to sustain fish populations). To explore whether DSCS provide essential habitats for demersal fishes, we analyzed 10 years of su...
Technical Report
Full-text available
This study developed maps of the modeled spatial distributions of deepsea corals, sponges, and benthic macrofauna offshore of the continental US West Coast to 1,200 m depth. Occurrence data for deep-sea corals, sponges, and macrofauna and spatial environmental predictors depicting seafloor topography, substrate, oceanography, and geography were use...
Article
Noise produced by scientific equipment during fisheries surveys is largely unstudied, though these sound sources may have an effect on the organisms of interest and on their resultant stock assessments. This paper describes acoustic signatures of two underwater mobile vehicles and accompanying research ships used to survey demersal fishes, and disc...
Technical Report
Full-text available
This annex to the U.S. West Coast chapter in “The State of Deep-Sea Coral and Sponge Ecosystems of the United States” provides a list of deep-sea coral taxa in the Phylum Cnidaria, Classes Anthozoa and Hydrozoa, known to occur in U.S. waters off Washington, Oregon, and California. Deep-sea corals are defined as azooxanthellate, heterotrophic coral...
Article
We evaluated disturbance and damage to deep-sea corals and sponges (DSCS) in areas of longtime (> 65 years) bottom trawling off southern Oregon and northern California. The incidence of disturbance was quantified from video and still images collected along strip transects conducted with underwater vehicles operating at depths of 600-2100. m. All DS...
Article
Impacts of ambient noise in the ocean are a concern for fish populations, as well as for other marine vertebrates. The influence of noise associated with mobile equipment, such as autonomous vehicles and occupied submarines used to survey demersal rockfishes (genus Sebastes), has not previously been quantified. Such noise likely occurs within the s...
Article
Full-text available
Determining the prey composition and foraging habitats of U.S. Pacific Coast groundfishes are specified management directives that have not received much scientific attention. To address this knowledge gap, we conducted a meta-analysis of the feeding ecology of 18 commercially important species and their life stages during a recent review of Pacifi...
Article
Garden eels occur worldwide in the tropics, but little is known about their biology and ecology. We studied Hawaiian garden eel (Gorgasia hawaiiensis) colonies near Kawaihae, Hawai'i, to investigate multiple aspects of basic biology of this species. Colonies of G. hawaiiensis occurred at depths from 16 to 36 m in soft-bottom habitat adjacent to roc...
Article
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Visual surveys of seafloor communities in deep water are becoming more common and provide fishery-independent abundance estimates that could improve stock assessments for some groundfish species. However, limitations of the survey vehicle must be considered when developing methods. To that end, we estimated densities of demersal fishes from 28 pair...
Article
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Understanding the association between components of habitat and fish distribution and abundance is important in order to achieve accurate stock assessments. We developed gen - eralized additive models (GAM) and spatially predictive maps of rockfish abundance at the individual species level using habitat descriptors collected from visual surveys and...
Article
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Skates (Rajiformes: Rajoidei) are common mesopredators in marine benthic communities. The spatial associations of individual species and the structure of assemblages are of considerable importance for effective monitoring and management of exploited skate populations. This study investigated the spatial associations of eastern North Pacific (ENP) s...
Article
Full-text available
We examined the reactions of fishes to a manned submersible and a remotely operated vehicle (ROV) during surveys conducted in habitats of rock and mud at depths of 30-408 m off central California in 2007. We observed 26 taxa for 10,550 fishes observed from the submersible and for 16,158 fishes observed from the ROV. A reaction was defined as a dist...
Article
Full-text available
The Christmas tree coral Antipathes dendrochristos is a recently discovered black coral species that represents a habitat associated with numerous sensitive taxa in the Southern California Bight. We evaluated whether broad-scale oceanographic features influence coral density and size by selecting from among generalized additive models (for density)...
Technical Report
In 2007, the California Ocean Protection Council initiated the California Seafloor Mapping Program (CSMP), designed to create a comprehensive seafloor map of high-resolution bathymetry, marine benthic habitats, and geology within the 3-nautical-mile limit of California’s State Waters. The CSMP approach is to create highly detailed seafloor maps thr...
Conference Paper
NOAAs Southwest Fisheries Region and Science Center have developed an initiative to assess deepwater seafloor communities in the Southern California Bight (SCB). Offshore habitats in the SCB include rocky banks, seamounts, basins, and submarine canyons that span about 75,000 km2 and are influenced by a dynamic mixture of cold nutrient-rich water fr...
Conference Paper
Full-text available
The National Oceanic and Atmospheric Administration’s (NOAA’s) Deep Sea Coral Research and Technology Program, has launched a three-year research initiative on the West Coast of the United States to locate, study, and provide information for the protection of deep sea coral and sponge habitats. The newly collected information will inform proposals...
Chapter
Full-text available
This book started as an idea at the GeoHab meeting held in Noumea, New Caledonia, in May 2007. We noticed that multibeam bathymetry maps of geomorphic features, sometimes shown as 3D fly-thru movies, followed by detailed sampling and photographic data (including underwater videos) illustrating the substrate conditions and associated biota was a con...
Article
Full-text available
Presence-absence data of benthic macro-invertebrates and associated habitat (i.e., sediment type and depth) were collected using a towed camera sled in selected areas along the coast off southern California. Using this information, we developed generalized linear models (GLMs) to predict the probability of occurrence of five commonly observed taxa...
Chapter
Full-text available
Southeastern Bay of Biscay (Basque coast) seafloor characterization and benthic habitat mapping was carried out integrating data from multibeam echosounder, topographic and bathymetric LiDAR, video, and sediment and biological sampling ranging from the intertidal zone up to 100 m depth over 1,096 km 2. The area shows high geomorpho-logic diversity...
Article
The Ascension-Monterey canyon system, located in the vicinity of Monterey Bay about 160 km south of San Francisco, is the largest seafloor physiographic feature on the continental margin of California. This feature is located within the tectonically deformed 100-km-wide boundary between the Pacific and North American plates, represented by the San...
Conference Paper
Many fish stocks have strong affinities to specific habitats, resulting in patchy spatial distributions in abundance. Sample stratification or otherwise explicitly incorporating habitats into survey design can increase precision and accuracy of estimated densities of these stocks. Several economically valuable rockfish species off Alaska and the We...
Conference Paper
Marine scientists and resource managers have an increasing need for systematic information to guide management decisions related to benthic ecosystems. Such information requires visual surveys of seafloor habitats and associated species using undersea technologies. Availablem technologies range widely in cost and capabilities, and matching manageme...
Article
Full-text available
Community interactions alter the management actions necessary to recover overfished species using marine reserves. For example, in communities where a larger species preys on their juveniles' competitors, overfishing of the larger species may cause prey population expansion; subsequent increased competition for the juveniles of the over fished spec...
Article
Abundances of Pacific pomfret (Brama japonica), an epipelagic fish of the North Pacific Ocean, were estimated from gillnet catches during the summers of 1978–1989. Two size modes were common: small pomfret <1 yr old, and large fish ages 1–6. Large and small fish moved northward as temperatures increased, but large fish migrated farther north, often...
Technical Report
Full-text available
This report provides summaries and characterizations of information developed during Phase 1 of the EFH 5-year review (2012). It is not intended as a full EFH analysis, but rather, to provide supporting and contextual information for those making proposals or evaluating proposals in Phase 2. There are a variety of aspects that are not addressed in...
Conference Paper
The Habitat Assessment Improvement Plan (HAIP) is the first nationally coordinated plan to focus on the marine fisheries aspects of habitat science. It addresses the lack of knowledge regarding the association of marine species and their habitats, which impedes effective fisheries and habitat management, protection, restoration, and stock assessmen...
Article
Full-text available
Marine debris is a global concern that pollutes the world’s oceans, including deep benthic habitats where little is known about the extent of the problem. We provide the first quantitative assessment of debris on the seafloor (20–365 m depth) in submarine canyons and the continental shelf off California, using the Delta submersible. Fishing activit...
Article
Full-text available
Between 1995 and 2006, manned submersible fish surveys were conducted on the sea floor throughout the Southern California Bight. A total of 401 dives (comprising 1,015 transects and 14,373 habitat patches) were made in waters between 19 and 365m deep. All natural habitat types were included, although both soft sea floors and rocky reefs were survey...
Article
In 2004, we surveyed demersal fishes and habitats on the continental shelf off central California (65–110 m depth) using the occupied submersible Delta. Our objectives were to estimate the relative abundance of habitats and to examine demersal fish species composition, diversity, density, and sizes relative to these habitats. A total of 112 transec...
Article
Full-text available
Habitat associations and the effect of predators on dwarf rockfishes (Sebastes spp.) were investigated in two large marine protected areas (MPAs) off southern California. Using data from submersible surveys, the occurrence and abundance of dwarf rockfishes were modeled using substrata types and the biomass of predators as predictor variables. The o...
Article
We applied dendrochronology (tree-ring) methods to develop multidecadal growth chronologies from the increment widths of yelloweye rockfish (Sebastes ruberrimus) otoliths. Chronologies were developed for the central California coast, a site just north of Vancouver Island, British Columbia, and at Bowie Seamount west of the Queen Charlotte Islands,...
Article
Full-text available
We characterized habitat requirements of juvenile cowcod, Sebastes levis, using information from surveys conducted aboard the manned research submersible Delta. We conducted 303 dive surveys on rocky banks and outcrops in water depths between 28 and 365m in southern and central California, covering 483km (963,940m2) of seafloor. We counted 549,263...
Book
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Recent experience in implementing legal requirements to designate and protect Essential Fish Habitat for groundfish off the US west coast is providing an opportunity to develop a feedback loop between science and policy for habitat- and ecosystem-based management that mirrors the traditional stock assessment/harvest management paradigm. The stock a...
Article
Full-text available
A meaningful assessment of cowcod (Sebastes levis) has been conducted using visual, nonextractive, habitat-specific methods. Following the precipitous decline of rockfish (Sebastes spp.) stocks along the Pacific coast, it was evident that more effective methods were needed to assess several species in untrawlable habitats. Cowcod were surveyed with...
Article
Full-text available
Recent experience in implementing legal requirements to designate andprotect Essential Fish Habitatfor groundfish off the US west coast is providing an opportunity to develop a feedback loop between science and policy for habitat-and 451 COPPS ETAL. ecosystem-based management that mirrors the traditional stock assessment/harvest management paradigm...
Article
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"Fish-habitat associations were examined at three spatial scales in Monterey Bay, California, to determine how benthic habitats and land- scape configuration have structured deepwater demersal fish assemblages. Fish counts and habitat variables were quantified by using observer and video data collected from a submersible. Fish responded to benthic...
Article
Full-text available
In 2005, a dead 2.1-m high colony of the Christmas tree black coral, Antipathes dendrochristos Opresko, 2005, was collected from 106 m of water off southern California. Based on growth increment counts, a radiocarbon ( 14C) analysis, and an indirect corroboration by lead-210 dating from a second, live colony, the colony was about 140 yrs old when i...
Chapter
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Laser Line Scan (LLS) systems can serve as a bridge between fine-resolution, low-coverage video survey tools (e.g., Remotely Operated Vehicle (ROV), manned submersible, towed sled) and coarse-resolution, high-coverage acoustic technologies (e.g., multibeam andsidescan sonar). In an evaluation ofLLSforfishery habitat assessments, a survey was conduc...
Article
Full-text available
There is increasing interest in the potential impacts that fishing activities have on megafaunal benthic invertebrates occurring in continental shelf and slope ecosystems. We examined how the structure, size, and high-density aggregations of invertebrates provided structural relief for fishes in continental shelf and slope ecosystems off southern C...
Chapter
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Estuaries are among the most productive areas on earth, and fish biomass in these habitats ranks with that of the marine regions of upwelling, coral reefs, and kelp beds. This chapter characterizes California bay-estuarine fish assemblages from two broad perspectives: latitudinal distribution patterns, and major ecological features. The coastline f...
Article
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This chapter discusses those fishes characteristically found on or over complex seafloor habitats comprising various amounts of cobble, boulders, and rock outcrops in water depths ranging from 30 to 500 m. This depth range encompasses the continental shelf and upper continental slope of California. This chapter also discusses those fishes associate...
Article
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In October of 2003, intriguing northeast-trending faults displaying characteristics of rifting processes were imaged during a fish-habitat related high-resolution multibeam mapping survey of Dall Bank, a shallow submarine bank within the southern California Borderland. These structures are of extreme interest as they are aligned perpendicular to th...
Article
Full-text available
We applied crossdating, a dendrochronology (tree-ring analysis) age validation technique, to growth increment widths of 50 Sebastes diploproa otoliths ranging from 30 to 84 years in age. Synchronous growth patterns were matched by the following: (i) checking the dates of conspicuously narrow growth increments for agreement among samples and (ii) st...
Conference Paper
Full-text available
Underwater Video Spot Detector (UVSD) is a software package designed to analyze underwater video for continuous spatial measurements (path traveled, distance to the bottom, roughness of the surface etc.) Laser beams of known geometry are often used in underwater imagery to estimate the distance to the bottom. This estimation is based on the manual...
Conference Paper
We conducted a 9-day field test of laser line scan (LLS) imaging technology to characterize and explore seafloor habitats in and around the Big Creek Marine Ecological Reserve (BCER) within the Monterey Bay National Marine Sanctuary off the central California coast. Our goal was to evaluate the utility of LLS technology for assessing the distributi...
Article
Full-text available
Big Creek Marine Ecological Reserve (BCER), located off the central California coast, has been closed to fishing since January 1994. We used side scan sonar and an occupied submersible to collect baseline information on species-habitat relationships, density, and species and size composition of fish inside and outside BCER. Forty-three dives were m...
Article
Full-text available
A number of ecologically and economically impor- tant species of rockfishes recruited to soft benthic habi- tats in Monterey Bay, Cahfornia, during 1995-96. Sebastes elongatus, S. saxicola, and S. levis were the most abun- dant and, although caught throughout the depth range (40-100 in) of our survey, had highest densities from 60 to 100 ni. Densit...
Article
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‐A multidisciplinary assess- ment,of benthic ,rockfishes,(genus Se- bastes) and associated,habitats,in deep water,was ,conducted ,in Soquel ,Sub- marine Canyon, Monterey Bay, Califor- nia. Rock habitats,at depths,to 300 m
Article
A standard, universally useful classification scheme for deepwater habitats needs to be established so that descriptions of these habitats can be accurately and efficiently applied among scientific disciplines. In recent years many marine benthic habitats in deep water have been described using geophysical and biological data. These descriptions ca...
Article
Rockfish are among the most prevalent members of nearshore ichthyoplankton assemblages off central California, yet their abundance varies greatly from year to year. Warm events, like El Niño, can have pronounced effects on the success of a year class. We evaluate distribution, abundance, and species composition of rockfish larvae on small spatial a...
Article
Interannual variability in growth of larval walleye pollock Theragra chalcogramma was examined from 1983 to 1991 and of juveniles from 1985 to 1990. ANCOVA was used to assess differences in population growth rates, and an alternate method was developed to examine variations between annual length-at-age data and average 'expected' values over differ...
Article
Full-text available
Food habits of the dominant fishes collected from 1974 to 1980 at eight locations in Elkhorn Slough, California, and the adjacent ocean were investigated. Epifaunal crustacea was the major prey group identified from stomach contents of more than 2,000 fishes, followed by epifaunal and infaunal worms, and molluscs. Overall, 18 fish species consumed...