Roundscale Spearfish Head Morphology
Project (PRJ) | Southeast Fisheries Science Center (SEFSC)GUID: gov.noaa.nmfs.inport:26098 | Updated: August 9, 2022 | Published / External
-
View As
- Full List View
- Printable Form
- EXPORTS
- InPort XML
- View in Hierarchy
Summary
The morphometric characteristics that separate white marlin Kajikia albidus from roundscale spearfish Tetrapturus georgii can be difficult for non-experts to distinguish, particularly when the animals are in the water. Using the measurements of the lower jaw tip to the longest branchiostegal ray (LJBR) and the opercle (LJOP), a discriminant function is presented that will help field observers separate the two species. The function DR-W = LJBR (3.31861) + LJOP (-2.84856) – 6.37198 classified specimens as roundscale spearfish when DR-W was > 0 and as white marlin when DR-W < 0 with a 95% correct classification rate overall. Since only the head of a specimen needs to be closely observed, the method has particular utility for tournament anglers during the hook removal process.
Project Information
Project Type
Project
Mandated By
MSRA, MMPA, ESA, Atlantic HMS Regulations
Collection Type
Observer
Collection Method
Biological Samples, Paper, Electronic
Child Items
Type | Title |
---|---|
Data Set | ROUNDSCALE SPEARFISH branchiostegal morphometric data |
Contact Information
Point of Contact
Larry Beerkircher
lawrence.r.beerkircher@noaa.gov
305-361-4290
Metadata Contact
Larry Beerkircher
lawrence.r.beerkircher@noaa.gov
305-361-4290
Extents
-95° W,
-44° E,
46° N,
7° S
Item Identification
Title: | Roundscale Spearfish Head Morphology |
---|---|
Status: | Completed |
Abstract: |
The morphometric characteristics that separate white marlin Kajikia albidus from roundscale spearfish Tetrapturus georgii can be difficult for non-experts to distinguish, particularly when the animals are in the water. Using the measurements of the lower jaw tip to the longest branchiostegal ray (LJBR) and the opercle (LJOP), a discriminant function is presented that will help field observers separate the two species. The function DR-W = LJBR (3.31861) + LJOP (-2.84856) – 6.37198 classified specimens as roundscale spearfish when DR-W was > 0 and as white marlin when DR-W < 0 with a 95% correct classification rate overall. Since only the head of a specimen needs to be closely observed, the method has particular utility for tournament anglers during the hook removal process. |
Notes: |
Data were collected as part of the POP |
Other Citation Details: |
Beerkircher and Serafy 2011. Using head measurements to distinguish white marlin Kajikia albida from roundscale spearfish Tetrapturus georgii in the western North Atlantic. Bull. Mar. Sci. 87(1):147-153 |
Keywords
Theme Keywords
Thesaurus | Keyword |
---|---|
UNCONTROLLED | |
None | BILLFISH |
None | IDENTIFICATION |
None | MORPHOLOGY |
None | SPEARFISH |
None | WHITE MARLIN |
Spatial Keywords
Thesaurus | Keyword |
---|---|
UNCONTROLLED | |
None | ATlantic |
None | CAribbean |
None | Gulf of MExico |
Physical Location
Organization: | Southeast Fisheries Science Center |
---|---|
City: | Miami |
State/Province: | FL |
Country: | USA |
Project Information
Project Type: | Project |
---|---|
Is Mandated?: | Yes |
Mandated By: | MSRA, MMPA, ESA, Atlantic HMS Regulations |
Collection Type: | Observer |
Collection Authority: | Federal |
Collection Method: | Biological Samples, Paper, Electronic |
Support Roles
Data Steward
Date Effective From: | 2008 |
---|---|
Date Effective To: | |
Contact (Person): | Beerkircher, Larry |
Address: |
75 Virginia Beach Drive Miami, FL 33149 |
Email Address: | lawrence.r.beerkircher@noaa.gov |
Phone: | 305-361-4290 |
Contact Instructions: |
Contact by email preferred. |
Distributor
Date Effective From: | 2008 |
---|---|
Date Effective To: | |
Contact (Organization): | Southeast Fisheries Science Center (SEFSC) |
Address: |
75 Virginia Beach Drive Miami, FL 33149 USA |
Phone: | (305)361-5761 |
URL: | https://www.fisheries.noaa.gov/about/southeast-fisheries-science-center |
Business Hours: | 8:00 a.m. - 4:30 p.m. EST |
Contact Instructions: |
Contact by email preferred. |
Metadata Contact
Date Effective From: | 2008 |
---|---|
Date Effective To: | |
Contact (Person): | Beerkircher, Larry |
Address: |
75 Virginia Beach Drive Miami, FL 33149 |
Email Address: | lawrence.r.beerkircher@noaa.gov |
Phone: | 305-361-4290 |
Contact Instructions: |
Contact by email preferred. |
Point of Contact
Date Effective From: | 2008 |
---|---|
Date Effective To: | |
Contact (Person): | Beerkircher, Larry |
Address: |
75 Virginia Beach Drive Miami, FL 33149 |
Email Address: | lawrence.r.beerkircher@noaa.gov |
Phone: | 305-361-4290 |
Contact Instructions: |
Contact by email preferred. |
Extents
Extent Group 1
Extent Group 1 / Geographic Area 1
W° Bound: | -95 | |
---|---|---|
E° Bound: | -44 | |
N° Bound: | 46 | |
S° Bound: | 7 |
Access Information
Security Class: | Unclassified |
---|---|
Data Access Procedure: |
Contact POC |
Data Access Constraints: |
Waiver Needed |
Data Quality
Representativeness: |
Unknown. Likely only Representative of the white marlin and RSSP captured at these times and places by PLL vessels. |
---|---|
Accuracy: |
Nothing is known about the degree of agreement between individual measurements in the POPOL data set and the true measurements, as the observer collecting the data is the sole source of the information and it cannot be cross checked with alternate sources. |
Analytical Accuracy: |
See above. The accuracy of analytical results to the “true” values cannot be determined as the true values cannot be calculated without 100 % observer coverage and multiple observers on each vessel. Neither situation has ever occurred during collection of POPOL data. |
Quantitation Limits: |
No limits. The species size range captured on board pelagic longline vessels can be easily measured by observers with standard hand measuring devices. |
Bias: |
There have been no quantitative studies to detect potential bias in POPOL. |
Comparability: |
There are no known comparable data sets . |
Completeness Measure: |
Only dead specimens could be measured; observations of live white marlin or roundscale spearfish did not include the complete detailed measurements. |
Precision: |
A hand centimeter measuring tool, collecting data to the nearest centimeter, can be expected to be very precise. |
Analytical Precision: |
No information available. |
Field Precision: |
No information available. |
Sensitivity: |
No information available. |
Detection Limit: |
See above, specimen needed to be dead and brought on board by the crew in order for the observer to take the complete data needed. |
Child Items
Rubric scores updated every 15m
Type | Title | |
---|---|---|
Data Set | ROUNDSCALE SPEARFISH branchiostegal morphometric data |
Catalog Details
Catalog Item ID: | 26098 |
---|---|
GUID: | gov.noaa.nmfs.inport:26098 |
Metadata Record Created By: | Lee M Weinberger |
Metadata Record Created: | 2015-07-24 15:23+0000 |
Metadata Record Last Modified By: | SysAdmin InPortAdmin |
Metadata Record Last Modified: | 2022-08-09 17:11+0000 |
Metadata Record Published: | 2021-05-06 |
Owner Org: | SEFSC |
Metadata Publication Status: | Published Externally |
Do Not Publish?: | N |
Metadata Last Review Date: | 2021-05-06 |
Metadata Review Frequency: | 1 Year |
Metadata Next Review Date: | 2022-05-06 |