7.14 Ministry of Fisheries longline database (tuna) (l-line)

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Database Title	7.14 Ministry of Fisheries longline database (tuna) (l-line)
Keywords Type1. Type 11.	New Zealand EEZ; marine; oceans; fisheries; tuna; length; weight; sex; catch; distribution; bycatch; ;longline; tuna
Abstract	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
Status/currency.	In progress
Update frequency.	Annual
Maintenance.	NIWA
Database size.	16,335 kb.

Technical Evaluation
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: Catch rates Geographical distribution of sample caught Estimated amount of fish caught across the whole fleet.
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	NIWA
Database custodian contact person	Don Robertson
Database custodian Contact Address Phone Fax Email	PO Box 14 901 Kilbirnie Wellington + 64 4 386 0519 + 64 4 386 0572 d.robertson@niwa.cri.nz
References	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

Management Evaluation
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
Database strengths.	There are many records The data has been collected by reliable objective observers and is of good quality
Database limitations.	There is not much observer coverage of catches on smaller domestic longline vessels. This is because it is more difficult to take out an observer on these vessels. In 1987-88 observer coverage was 82% for the foreign and charter fleet but <3% for the domestic fleet.

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.