Larval Fish Identification from Cruises at Oahu, TC-85-04, TC-85-05, TC-86-02, TC-86-04

Four cruises aboard the NOAA ship Townsend Cromwell were conducted, collectors included George Boehlert and Bruce Mundy. Two transects, oriented in an east-west direction, were established, one each on the leeward and the windward sides of the island. Stations were located 1.8, 9.3, and 27.8 km from shore along the leeward side and 3.7, 9.3, and 27.8 km from shore along the windward side. Larvae were sampled below the surface with a 1 m2 multiple opening-closing net and environmental sensing system (MOCNESS) and at the sea surface with a 0.49 m2 Manta net modified to take surface samples to a depth of 0.7 m. All nets were constructed of 0.333 mm Nitex mesh. Estimates of water volumes filtered by both gear types were based on mechanical flowmeter readings. Samples were taken in eight depth strata (neuston, 0-10, 10-20, 20-30, 30-40, 40-50, 50-60, and 60-80 m) at each nearshore station and in nine depth strata (neuston, 0-20, 20-40, 40-60, 60-80, 80-100, 100-120, 120-160, and 160-200 m) at the 4 offshore stations. MOCNESS hauls were 12 minutes duration for each net (stratum), fished in a stepped oblique fashion from deep to shallow with mean tow speeds of approximately 75 cm/sec; the tow speed was adjusted to maintain a net mouth angle near 45". Neuston tows were 24 minutes, taken during the mid-point of the MOCNESS tows. Replicate tows were taken at each station in both day and night, but only the first replicate sample was sorted for the December, April, and June cruises, whereas both replicates were processed for the September cruise.

All fish larvae were identified to the lowest taxonomic level possible by Bruce C. Mundy. Squid paralarvae were transferred to the Dr. Richard Young (Dept. of Oceanography, Univ. of Hawai'i). Other taxa were not routinely sorted, but heteropods from selected samples have been transferred to Dr. Roger Seapy (Dept. of Biological Sciences, California State Univ. Fullerton; see Seapy 1990. Patterns of vertical distribution in epipelagic heteropod molluscs off Hawaii. Mar. Eco1.-Prog. Ser., 60: 235-246.) and numbers of four species of copepods were obtained from subsamples from certain stations by Dr. R. Patrick Hassett (Dept. of Zoology, Arizona State Univ.; see Hassett and Boehlert 1995. Seasonal, vertical and horizontal distributions of four species of copepods around Oahu, Hawaii: data report. NOAA Tech. Memo. NMFS, NOAA-TM-NMFS-SWFSC-215, 21 p.).

To identify fish larvae caught around the Hawaiian Islands.

Media is stored at the IRC on paper, on a 5.25" floppy, 3.5" diskette, a Zip cartridge, and a Bernouili cartridge.

Record count: 13,091

Station latitude and longitude were not collected on the data entry form. The station location list from the cruise reports will be provided in pdf format in the BagIt data/doc folder.

Larval fish data and a more detailed description of the study were published in Boehlert & Mundy (1996. Ichthyoplankton vertical distribution near Oahu, Hawai`i, 1985?1986: data report. NOAA Technical Memorandum, NMFS NOAA-TM-NMFS-SWFSC-235: 1?148.) and Boehlert and Mundy (1994. Vertical and onshore-offshore distributional patterns of tuna larvae in relation to physical habitat features. Mar. Ecol., Prog. Ser. 107: 1-13.)

SOURCE ID: RB008

Send written request to PIFSC and get approval by the PIFSC data owner.

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Oracle database

QC review prior to data entry. Further QC after data entry.

PIFSC ITS performs scheduled back-ups.

Data was collected in the field by PIFSC staff, and entered in table format into electronic spreadsheets.