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ANNEX 2. FISHING EFFORT MEASURES BY GEAR CATEGORIES

These measures are modified from Appendix T of the Report of the Ad Hoc Consultation on the Role of Regional Fishery Agencies in Relation to High Seas Fishery Statistics (La Jolla, California, USA, 13-16 December 1993), FAO Fisheries Report No. 500. The measures are suggested for the purpose of carrying out stock assessment. The measures may require modification or additional information before being appropriate for other purposes.

FISHING GEAR

EFFORT MEASURE DESCRIPTORS

DEFINITION

FIRST PRIORITY

Surrounding nets (e.g. purse seines)

Number of sets

Number of times the gear has been set or shot, whether or not a catch was made. This measure is appropriate when school size and packing density is related to stock abundance or sets are made in a random manner.

Surrounding nets (e.g. purse seines)

Searching time

This represents time on the grounds less time spent shooting net and retrieving the catch as well as time hove to. This measure is complicated by the use of aircraft spotting as well as by the dissemination of information from vessel to vessel. The measure is appropriate when school size and packing density are unrelated to stock abundance and a set is only made when a school has been located.

Surrounding nets (e.g. purse seines) if fishing with Fish Attracting Device (FAD)

Number of hours since last fishing this FAD

Time in which FAD (Fishing Attracting Device) is left in the water since it was last fished.

Boat seines (Danish seine, etc.)

Number of hours fished

Number of hours during which the seine was on the bottom and fishing.

Beach seines

Number of sets

Number of times the gear has been set or shot, whether or not a catch was made.

Castnet

Number of casts

Number of times the gear has been cast, whether or not a catch was made.

Trawls

Number of hours fished

Number of hours during which the trawl was in the water (midwater trawl), or on the bottom (bottom trawl), and fishing.

Boat dredges

Number of hours fished

Number of hours during which the dredge was on the bottom and fishing.

Gillnets (set or drift)

Number of effort units

Length of nets expressed in 100-metre units multiplied by the number of sets made (= accumulated total length in metres of nets used in a given time period divided by 100).

Gillnets (fixed)

Number of effort units

Length of net expressed in 100-metre units multiplied by the number of times the net was cleared.

Lift net

Number of hours fished

Number of hours during which the net was in the water, whether or not a catch was made.

Traps (uncovered pound nets)

Number of effort units

Number of days fished times the number of units hauled.

Covered pots and fyke nets

Number of effort units

Number of lifts times the number of units (= total number of units fished in a given time period).

Longlines (set or drift)

Numbers of hooks

Number of hooks fished in a given time period.

Pole-and-line

Number of days fished

The number of days (24-hour periods, reckoned from midnight to midnight), on which any fishing took place, including days during which searching took place without fishing.

Rod-and-reel (recreational)

Number of line-hours

Number of hours during which the lines were in the water times number of lines used.

Troll

Number of line-days

Total number of line days in the given time period.

Jigs (hand and mechanical)

Number of line-days

Total number of line days in the given time period.

Other small scale net gears

Number of operations

Those small scale gears including push net, scoop net, drive-in net etc. Number of fishing operation, whether or not a catch was made.

Other small scale stationary gears

Number of hours fished

Those gears include guiding barriers, bag net, stow net, portable net, etc. Number of hours during which the gears were in the water for fishing, whether or not a catch was made.

Harpoons, spears etc.

Number of days fished

The number of days (24-hour periods, reckoned from midnight to midnight), on which any fishing took place, including days during which searching took place without fishing.

SECOND PRIORITY

Boat seines (Danish seine, etc.)

Number of sets made

Number of times the gear has been set or shot, whether or not a catch was made.

Trawls

Number of sets made

Number of times the gear has been set or shot (either in mid-water or to the bottom), whether or not a catch was made.

Lift net

Number of hours fished

Number of times the net was set or shot in the water, whether or not a catch was made.

All gears

Number of days fished

The number of days (24-hour period, reckoned from midnight to midnight) on which any fishing took place. For those fisheries in which searching is a substantial part of the fishing operation, days in which searching but no fishing took place should be included in "days fished" data.

THIRD PRIORITY

All gears

Number of days on ground

The number of days (24-hour periods, reckoned from midnight to midnight), in which the vessel was on the fishing ground, and includes in addition to the days fishing and searching also all the other days while the vessel was on the ground.

FOURTH PRIORITY

All gears

Number of days absent from port

The number of days absent from port on any one trip should include the day the fishing craft sailed but not the day of landing. Where it is known that fishing took place on each day of the trip the number of "days absent from port" should include not only the day of departure but also the day of arrival back in port. Where on any trip a fishing craft visits more than one "fishing area" (as defined for statistical purposes) an appropriate fraction of the total number of days absent from port should be allocated to each "fishing area" in proportion to the number of days spent in each, so that the total number of days absent on the trip will be the sum of the number of days allocated to all of the different "fishing areas" visited.

FIFTH PRIORITY

All gears

Number of trips made

Any voyage during which fishing took place in only one "fishing area" is to be counted as one trip. When in a single trip a craft visits more than one "fishing area" an appropriate fraction of the trips should be apportioned to each "fishing area" in proportion to the number of days spent fishing in each, so that the total number of trips for the Statistical Area as a whole will be the same as the sum of trips to each "fishing area".


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