Catch data from New Zealand research trawls since 2008

Kevin Mackay

doi:10.15468/gzpcyl

Catch data from New Zealand research trawls since 2008

Citation

Mackay K (2019). Catch data from New Zealand research trawls since 2008. Version 1.23. Southwestern Pacific Ocean Biogeographic Information System (OBIS) Node. Sampling event dataset https://doi.org/10.15468/gzpcyl accessed via GBIF.org on 2020-01-18.

Description

This dataset contains data from research trawls that have occurred since 2008 and are stored the NIWA/MPI Trawl database These data results from data collected by research trawl surveys on research vessels and chartered commercial fishing vessels. Trawl surveys are a major tool used by research scientists for stock assessment. They are used to estimate basic parameters of commercial fish populations, including biomass, sex ratio, and the proportion of sexually mature fish, and the distribution of ages and lengths in the population. These parameters may be used in estimating mortality and growth rates.

This dataset is a continuation of data from the NIWA/MPI Trawl database that was initially released as the New Zealand fish and squid distributions from research bottom trawls 1964-2008 available at https://nzobisipt.niwa.co.nz/resource?r=obisprovider

Sampling Description

Study Extent

Fisheries research trawls since 2008 over the New Zealand EEZ area

Sampling

Most records are from random bottom trawls, but there are also records from midwater trawls, scampi trawls and non-random tows (such as gear trials and target tows).

Quality Control

The scientific names have been mapped to the World Register of Marine Species (WoRMS), using the online taxon match tool. All sampling locations have been plotted on a map to perform a visual check. The most important check would be to see if all sampling locations are (1) in the marine and/or brackish environment and (2) within the described sampling area.

Method steps

Only successful trawl records were selected. All “foul” shots are excluded as the net may have ripped and some species may have escaped on hauling. All species identification have been validated and outliers based on geographic and depth distributions have been checked.
Catch weights (kg) are added to the “occurrenceRemarks” field. -Sea temperature recorded by trawl headline sensors are added to the “dynamicProperties” field.

Additional info

marine, harvested by iOBIS

Taxonomic Coverages

Geographic Coverages

New Zealand region

Bibliographic Citations

Contacts

Kevin Mackay
originator
position: Marine Database Manager
NIWA
Private Bag 14-901
Wellington
6241
New Zealand
NZ

Kevin Mackay
metadata author
position: Marine Database Manager
NIWA
Private Bag 14-901
Wellington
6241
New Zealand
NZ

Kevin Mackay
user
email: kevin.mackay@niwa.co.nz

David Fisher
administrative point of contact
position: Principal Technician - Fisheries
NIWA
Private Bag 14-901
Wellington
6241
New Zealand
NZ