7.14 Ministry of Fisheries longline database (tuna) (l-line)
|New Zealand EEZ; marine; oceans; fisheries; tuna; length; weight; sex; catch; distribution; bycatch; ;longline; tuna|
This database contains data collected by scientific observers on a sample of foreign licensed and domestic commercial fishing vessels (average 7.5% but this increased over time) longlining for southern blue fin tuna, albacore and big eye. Long lines are up to 150km,with up to 3000 hooks and are set for about 24 hours.
From 1989 to present, approximately 60-110 sea days were sampled each year. Nearly 75% overall catch in number was from 4 tuna species.
|Geographical Coverage||New Zealand EEZ especially Northeast North Island, West Coast South Island, Fiordland, Snares Island shelf.|
|Dataset start date.||1987|
|Dataset end date.||Current|
|Database size.||16,335 kb.|
|Parameters- what is measured||For each fish: length measurements, weight, sex, maturity, stomach contents, whether live or dead, whether retained or discarded, damage, position on line where caught. Sometimes bycatch species are merely counted. Data is also collected about fishing gear and fishing effort.|
|Parameters- what is calculated||For each fish species:
|Methods used to measure parameters||The data is collected by Ministry of Fisheries scientific observers on commercial fishing vessels. They record every longline set over the duration of the voyage. They measure the parameters specified above and take samples for later analysis (e.g. genetic analysis)|
|Scale of use.||Variable|
|Number of records||To mid 1998 there had been 99 trips with 2604 sets and 6.9 million hooks,and >207,000records from 70 species|
|GIS compatibility.||Not to date.
It is possible as latitude and longitude data is collected.
|Available formats for users.||Electronic relational database; requests are usually responded to with a
flat file (Excel, ASCII).
Numerous reports that analyse the data
|Access constraints.||By request to the Ministry of Fisheries. There is no cost for the data although there is a NIWA charge to extract data.|
|Measurement Accuracy||To be completed by database manager.|
|Completeness of dataset||To be completed by database manager.|
|Positional accuracy||To be completed by database manager.|
|Database steward||Ministry of Fisheries|
|Steward contact person.||Kim Duckworth (Research Data Manager)|
|Database custodian contact person||Don Robertson|
|Database custodian Contact
| PO Box 14 901
+ 64 4 386 0519
+ 64 4 386 0572
Mackay, K.A; Kalish, S. 1995. Marine research database documentation. 14.l-line (tuna longline). NIWA Internal Report No 244; Bagley, N.W.; Anderson, O.F.; Hurst, R.J.; Francis, M.P.; Taylor, P.R.; Clark. M.R.; Paul, L.J. 2000(a). Atlas of New Zealand fish and squid distributions from mid water trawls, tuna long line sets, and aerial sightings. NIWA Technical Report 72. 171p.
Francis, M.P.; Griggs,L.H.; Baird, S.J.; Murray, T.E.; Dean,H.A. 2000(b). Fish bycatch in New Zealand tuna longline fisheries, 1988-89 to 1997-98. NIWA Technical Report 76. 79p.
|Date metadata record prepared.||June 2000|
|Author of metadata record.||Victoria Froude|
|Original purpose.||To improve fisheries management by assessing quantities and composition of fish caught.|
|Relationships with classification systems.||N/A|
|Relationships with other databases||Information from this database is used with other fisheries databases and physical databases to address various management and research questions.|
|Known relationships with proposed EPIP indicators.||May contribute to fisheries indicators.|
|Database uses?||Most of the data is used for single fish species analyses. FORST has funded NIWA research into fish communities to identify fish assemblages that regularly occur together (Bagley et al , 2000). The data is being used to identify the catch levels and maturity of pelagic sharks and striped marlin bycatch (Francis et al, 2000)|
|Public awareness of the database||Low/medium|
What are the Current and Emerging Uses of the Database for:
|Assisting with determining historic state/baseline.||The database provides time series data of historical catches of species sought and bycatch species.|
|Assisting with determining current state/baseline.||The fish distribution atlas (Francis et al, 2000(a)) maps species distribution by location and sometimes overall depth. The ratio of number of hooks observed, to the number of hooks in the fishery can be used as a check on what fishers are reporting.|
|Assisting with modeling possible future outcomes.||This can be done. Biological and commercial catch data would also be needed.|
|Risk assessment.||This is possible but has not been done so far other than a limited amount
for southern blue fin tuna.
The data has been used to assess risks to species caught as bycatch (Francis et al, 2000(b)).
|Monitoring site selection and sample design.||None known.|
|Aggregating and reporting data locally, regionally or nationally.||This is possible to aggregate over time and space.|