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Short Citation:
Pacific Islands Fisheries Science Center, 2024: Larval Fish Identification from Cruises at the Hancock Seamounts, TC-84-05 and TC-85-01,

Item Identification

Title: Larval Fish Identification from Cruises at the Hancock Seamounts, TC-84-05 and TC-85-01
Status: Completed
Publication Date: 1992-05-05

Ichthyoplankton sampling was conducted aboard the NOAA vessel Townsend Cromwell in 9-29 July 1984 and 4-10 February 1985. Collectors included George Boehlert, James Uchiyama, Robert Humphreys, Randolph Chang, Alan Everson, Victor Honda, Bert Kikkawa, Raymond Clarke, Thomas Kazama, and Michael Seki. Two locations were sampled intensively during these cruises; one location was over the seamount summit ("seamount" location); the other location was 20 km west, over a water depth of approximately 1,800-4,750 m ("reference" location).

Ichthyoplankton was sampled with an opening-closing Tucker trawl equipped with three nets and a double-release mechanism operated by messengers. The nets were 0.333 mm mesh (Nitex) with a 1.4 m2 mouth area. Ship speed was adjusted over tow speeds of about 0.9-1.1 m/second to maintain a wire angle at 45?. At this angle, the effective mouth area of the Tucker trawl is 1.0 m2 ; tow depths were estimated as a function of wire angle and meters of wire out. Four discrete depth strata (0-25, 25-50, 50-100, and 100-200 m) were sampled. Replicate tows at each depth comprised a sampling series. To sample at discrete depths without contamination by animals from shallower depths, the trawl was lowered with the first net open, and the second net was opened for the desired sampling time and then closed, and the trawl was retrieved with the third net open. To sample the two shallower strata, the trawl was lowered to 50 m, the second net was opened at that depth, and then the third net was opened at 25 m to sample the shallow stratum. For the two deeper strata, the second net was closed at the upper end of each stratum, and the trawl was retrieved with the third net open. Thus, a full set of duplicate samples for each depth stratum required six deployments of the trawl. The summer cruise had two series of night sampling (9-10 and 28-29 July) and one of day sampling (14-15 July); the winter cruise had one series of day and night sampling (4-10 February 1985). Each net was fished for 18 minutes and tows were conducted in a stepped oblique fashion, in an attempt to sample depths equally within each stratum. The volume of water filtered was estimated with calibrated General Oceanics flowmeters mounted in the center of each net. Plankton samples were preserved at sea in a 4% buffered formaldehyde seawater mixture. In the laboratory, plankton volume was determined from a known total volume minus the remaining water volume after the plankton were strained (Omori and Ikeda 1984); gelatinous plankton and fishes larger than approximately 50 mm were removed before the volume was determined. Whole samples were sorted for fish eggs, larvae, and squid para larvae under a dissecting microscope. Larval fishes were identified to the lowest possible taxonomic level by Bruce Mundy.


To compare ichthyoplankton species composition, distribution, and abundance in the Hancock Seamounts.


3,072 records

Supplemental Information:

The data are available in Boehlert & Mundy (1992. Distribution of ichthyoplankton around Southeast Hancock Seamount, central North Pacific, in summer 1984 and winter 1985: data report. NOAA Tech. Memo. NMFS, NOAA-TM-NMFSSWFSC-176: 1?109).



Theme Keywords

Thesaurus Keyword
None distribution
None eez
None ichthyoplankton
None LHP
None plankton
None seamount
None Townsend Cromwell
None tucker trawl

Spatial Keywords

Thesaurus Keyword
None Hancock Seamounts

Physical Location

Organization: Pacific Islands Fisheries Science Center
City: Honolulu
State/Province: HI
Country: USA

Data Set Information

Data Set Scope Code: Data Set
Data Set Type: Oracle Database
Maintenance Frequency: None Planned
Data Presentation Form: Table (digital)

Support Roles


CC ID: 233242
Date Effective From: 2015
Date Effective To:
Contact (Organization): Pacific Islands Fisheries Science Center (PIFSC)
Address: 1845 Wasp Blvd.
Honolulu, HI 96818
Email Address:
Phone: 808-725-5360
Business Hours: 8:00 a.m. - 4:30 p.m.

Point of Contact

CC ID: 1268704
Date Effective From: 2023-08
Date Effective To:
Contact (Person): Schemmel, Eva M
Email Address:
Contact Instructions:

Contact via email.

View Historical Support Roles


Currentness Reference: Ground Condition

Extent Group 1

Extent Group 1 / Geographic Area 1

CC ID: 44293
W° Bound: 178
E° Bound: 180
N° Bound: 31
S° Bound: 29

Hancock Seamounts

Extent Group 1 / Time Frame 1

CC ID: 44294
Time Frame Type: Range
Start: 1984-07-09
End: 1984-07-29

TC 84-05

Extent Group 1 / Time Frame 2

CC ID: 816634
Time Frame Type: Range
Start: 1985-02-04
End: 1985-02-16

TC 85-01

Access Information

Security Class: Unclassified
Data Access Procedure:

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

Data Access Constraints:


Metadata Access Constraints:


Metadata Use Constraints:


Distribution Information

Distribution 1

CC ID: 837047
Start Date: 2019-04-25
End Date: Present
Download URL:
Distributor: Pacific Islands Fisheries Science Center (PIFSC) (2015 - Present)


Issue 1

CC ID: 816910
Issue Date: 2019-01-30
Author: Miyamoto, Brent M

Miscoded species codes corrections made:

1) 6477 02 6477 to 6477 02 0523 - Euphausia gibboides - TC 85-01, station number 107, row number 47

2) 6477 02 0526 to 6477 02 0523 - Euphausia gibboides - TC 84-05, station number 106, row number 14 and TC 85-01, station number 108, row number 33

3) 8456 02 0400 to 8546 02 0400 - Scopelberyx sp. - TC 85-01, station number 108, row number 19

4) 6483 02 0806 to 6482 01 0806 - Gennedas propinquus - TC 85-01, station number 110, row number 21

5) 6483 02 0800 to 6482 01 0800 - Gennedas sp. - TC 85-01, station number 110, row number 22

6) 8531 23 1001 to 8531 32 1001 - Opostomias mistuii - TC 85-01, station number 132, row number 8

Technical Environment


Oracle database

Data Quality

Quality Control Procedures Employed:

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

Data Management

Have Resources for Management of these Data Been Identified?: Yes
Approximate Percentage of Budget for these Data Devoted to Data Management: Unknown
Do these Data Comply with the Data Access Directive?: Yes
Is Access to the Data Limited Based on an Approved Waiver?: No
Approximate Delay Between Data Collection and Dissemination: 1 Year
Actual or Planned Long-Term Data Archive Location: NCEI-MD
Approximate Delay Between Data Collection and Archiving: 1 Year
How Will the Data Be Protected from Accidental or Malicious Modification or Deletion Prior to Receipt by the Archive?:

PIFSC ITS performs regular backups of shared drives.


Lineage Statement:

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

Child Items

Rubric scores updated every 15m

Rubric Score Type Title
Entity RB006AA2_V

Catalog Details

Catalog Item ID: 8792
GUID: gov.noaa.nmfs.inport:8792
Metadata Record Created By: Brent M Miyamoto
Metadata Record Created: 2009-01-05 14:43+0000
Metadata Record Last Modified By: Brent M Miyamoto
Metadata Record Last Modified: 2023-08-25 22:39+0000
Metadata Record Published: 2019-07-23
Owner Org: PIFSC
Metadata Publication Status: Published Externally
Do Not Publish?: N
Metadata Last Review Date: 2019-07-23
Metadata Review Frequency: 1 Year
Metadata Next Review Date: 2020-07-23