By Atuna
The International Commission for the Conservation of Atlantic Tunas (ICCAT) has scheduled aerial surveys of bluefin tuna spawning population on several transects in the Mediterranean, where and when schools are traditionally sighted close to the surface in order to support the development of fishery-independent indices.
Right now the Commission is receiving applications from tenders to carry out the surveys, which should start on May 17th 2010.
Even though tenders are to propose the terms of the survey, the spawning sub-areas were already identified by ICCAT (see maps).
The surveys will be conducted only on bluefin tuna spawning aggregations in the period between 17 May and 18 July 2010 by several aircraft in the various sub-areas, at a spotting altitude of 300 m. The distance covered in a one-hour flight should be about 100 nm, with about 6 flight hours per day.
The operational budget for the first year survey campaign is sufficient for an estimated total of 69 days airtime (plus a total of 15 days stand-by time for adverse weather conditions). These days will be shared among the various sub-areas, each ranging from about 220 to about 540 square nautical miles.
According to ICCAT, it is reasonable to take into account adverse weather forecast of 20% of the days in spring/summer, which prevents a reliable observation of tuna schools close to the sea surface.
The Commission requires that the person performing the survey presents a preliminary report of the results by 20 June 2010, and a final report that must be submitted by 3 September 2010, at the latest.
The aerial bluefin surveys are an important element of the ICCAT Atlantic-Wide Research Programme on Bluefin Tuna (GBYP), which is required to improve basic data collection, understanding of key biological and ecological processes, assessment models and management of the species.
