The Early Life History (ELH) and Taxonomy Project is interested in several questions: What fish eggs and larvae occur in the Northeast Pacific? Where and when do they occur? How many are there? As a first step in answering these questions, all fish eggs and larvae that are collected during our extensive field studies must be identified as precisely as possible. This is the primary charge of the ELH and taxonomy project. Since the egg and larval stages of many fish in the Northeast Pacific are not yet described, project members spend a significant amount of time developing means to identify them. Once samples are identified, and the data properly stored, the specimens are transferred to the University of Washington Fish Collection for permanent archiving.
Current studies:
Northeast Pacific Ichthyoplankton Information System
A recent product the ELH and taxonomy project is the Northeast Pacific Ichthyoplankton Information System (IIS) (http://access.afsc.noaa.gov/ichthyo/index.php). The IIS answers the question of what fish eggs and larvae occur as well as where, when, and how many. This web site is the consolidation of our larval fish guide (Matarese, A.C., A.W Kendall, Jr., D.M. Blood, and B.M. Vinter. 1989. Laboratory guide to early life history stages of Northeast Pacific fishes. NOAA Tech. Rep. NMFS 80.) and the recently published larval distribution atlas (Matarese, A.C., D.M. Blood, S.J. Picquelle, and J.L. Benson. 2003. Atlas of abundance and distribution patterns of ichthyoplankton from the Northeast Pacific Ocean and Bering Sea ecosystems based on research conducted by the Alaska Fisheries Science Center (1972-1996). NOAA Prof. Paper NMFS 1.) This site provides access to current data on early life history of fishes collected by the Recruitment Processes Program at the Alaska Fisheries Science Center.
The AFSC IIS functions in two modes, a taxonomic search and character search, and allows users to view illustrations, meristic counts, information on ELH, and distribution and abundance maps. In addition, the site presents useful interactive links to FishBase and LarvalBase, the University of Washington's Fish Collection, and other ELH resources. The IIS offers a complete bibliography of early life history literature and provides the data used to make the distribution maps. Currently data and maps are available for about 1/3 of the taxa on the site. In the future, the database will be available with an option for downloading the information in PDF format. We welcome and encourage any questions or comments. Please contact any of the IIS subproject members: Debbie Blood or Ann Matarese.
Spawning, Egg Development, and Early Life History Dynamics of Arrowtooth Flounder, Atheresthes stomias
Arrowtooth flounder (Atheresthes stomias) has the highest biomass of any groundfish species in the Gulf of Alaska, is a voracious predator of age-1 walleye pollock (Theragra chalcogramma), a commercially important fish, and is a component in the diet of threatened and endangered Steller sea lion populations. Owing to its ecological importance and the limited information available on its reproduction, a study was undertaken in late January-February 2001-03 in the Gulf of Alaska to obtain information on adult spawning location, depth distribution, sexual maturity, and to obtain fertilized eggs for laboratory studies.
Adults were found 200-600 m deep over the outer continental shelf and upper slope southwest of Kodiak Island. Most ripe females were found at 400 m and most ripe males were found at depths >450 m.
Eggs were fertilized and incubated in the laboratory at 3.0°, 4.5°, and 6°C. Eggs were reared to hatching, but larvae did not survive long enough to complete yolk absorption and develop pigment. Eggs were staged according to morphological hallmarks and incubation data were used to produce a stage duration table and a regression model to estimate egg age based on water temperature and developmental stage.
Arrowtooth flounder eggs (1.58-1.98 mm in diameter, preserved) were collected in ichthyoplankton surveys along the continental shelf edge, primarily at depths ≥400 m.
Early stage eggs were found in tows that sampled to depths of ≥400 m. Larvae, which hatch between 3.9 and 4.8 mm standard length, increased in abundance with depth.
Oceanography, Ichthyoplankton, and Juvenile fish Assemblages of the Bering Strait and Chukchi Sea
A multidisciplinary research cruise was conducted in the Bering Strait and Chukchi Sea during summer 2004 aboard the Russian R/V Professor Khromov involving scientists from the School of Fisheries and Ocean Sciences at the University of Alaska Fairbanks. This was the first cruise of the Russian American Long Term Census of the Arctic (RUSALCA) program that is supported by the NOAA Office of Arctic Research and the Russian Academy of Sciences. The objectives were to document the ichthyoplankton and juvenile fish assemblages in the area and provide a baseline from which to measure future changes.
Ichthyoplankton and juvenile groundfishes were collected at approximately 18 stations in conjunction with physical data. Ichthyoplankton samples contained 23 taxa representing eight families and were dominated by Arctic cod, yellowfin sole, and Bering flounder. These three species constituted almost 43% of the ichthyoplankton catch.
Abundant Ichthyoplankton Species |
Scientific name | Common name | Percent of catch |
Boreogadus saida | Arctic cod | 23.0% |
Hippoglossoides robustus | Bering flounder | 10.8% |
Limanda aspera | Yellowfin sole | 8.8% |
All other taxa compose less than 5% of total catch |
Juvenile groundfish collections comprised 32 taxa in nine families. Catches were dominated by Arctic staghorn sculpin, shorthorn sculpin, and hamecon. Nine species constituted 91% of the catch.
Adult/Juvenile Beam Trawl Composition |
Species | Common name | Percent of catch |
Gymnocanthus tricuspis | Arctic staghorn sculpin | 33.8% |
Myoxocephalus scorpius | Shorthorn sculpin | 14.5% |
Artediellus scaber | Hamecon | 9.6% |
Lumpenus medius | Stout eelblenny | 7.8% |
Lumpenus fabricii | Slender eelblenny | 6.7% |
Hippoglossoides robustus | Bering flounder | 5.6% |
Eleginus gracilis | Saffron cod | 5.3% |
Stichaeus punctatus | Arctic shanny | 4.8% |
Boreogadus saida | Arctic cod | 2.9% |