Research plan for a COMHAFAT cetacean sighting survey in coastal waters of western North Africa in winter 2020
Samba T. Diallo
A plan is proposed for a cetacean sighting survey conducted by COMHAFAT in coastal waters of western North Africa in winter 2020. The study area is set mainly off Guinea, except for shallow waters less than 20 m for safe sailing. The purpose of this survey is to accumulate further information on distribution and abundance of whales including small cetaceans in the COMHAFAT zone. In this zone, zigzag track lines with around 1,013.2 nm of length are placed in the area. A 15-days survey period will be set in winter of 2020 season (in January and/or February of 2020). In the western North Africa, it is dry season in winter. Rain is scarce and wind is not so strong. Furthermore, it is expected that baleen whales migrate to the low latitudinal waters in winter. Thus, this season is thought to be suitable for cetacean sighting survey. The survey is started off Conakry, and finished off Guinea EEZ. The research vessel, GENERAL LANSANA CONTE of Guinea (198 tons), will be used. Researchers from COMHAFAT member states conduct the survey. Scientists from nonmember states, however, can be onboard, if the COMHAFAT and vessel capacity allow it. Cetacean searching is conducted from line transect method, under good weather condition (Beaufort wind scale of 3 or less and greater than 2 nm in visibility). Researchers search the sea surface for cetaceans from the vessel following the pre-determined track lines at around 10 knots. The normal closing mode survey is carried out, in which closing is made for all cetacean species encountered at searching.