Sei whale (Balaenoptera borealis) populations were severely depleted by about 80% during the commercial whaling industry of the mid-twentieth century, with most of the decline occurring in the Southern Hemisphere. Classified as ‘Endangered’ on the IUCN Red List, the present status of the South Atlantic population is still relatively unknown and no specific studies have been undertaken at the Falklands.

As a migratory species, sei whales are regularly sighted in coastal waters of the Falklands during the summer, and although their distribution is often variable from year to year, there are known ‘hotspots’ including Berkeley Sound, a partially enclosed water body (150km2) close to the capital of the Falklands. Berkeley Sound is the busiest shipping harbour at the Falklands, with peak activity occurring during the commercial fishing season. The possibility of inshore vessel to vessel oil transfers at Berkeley Sound, as a result of the offshore hydrocarbon industry emerging at the Falklands, also poses the potential to significantly increase marine activity. With local anecdotal evidence suggesting sei whale numbers may be increasing and with this predicted rise in commercial marine activities there is real potential for serious negative impacts on sei whales within the Sound and therefore a need to better knowledge to manage these increasing pressures.

The project had three broad objectives:

     1. To increase knowledge of sei whales, by carrying out scientific surveys to derive information on the number and distribution of sei whales and their interactions with human activities in Berkeley Sound;
     2. To raise awareness, by disseminating information on whales to the public, relevant stakeholders and decision-makers; and
     3. To provide management recommendations, with regard to mitigating any potential impacts on whales from human activities in Berkeley Sound and through the development of best practice guidance for maritime users, including those offering whale-watching ecotourism.

The intended project results have been delivered as follows:

In addition, the project has been successful in highlighting the Cape Pembroke peninsula as a feasible shore-based whale- and dolphin-watching venue that could bring socio-economic benefits to the Stanley area in terms of attracting tourists. To further develop this output, the BEST 2.0-funded sei whale project officer has worked with FIG to design and manufacture two interpretive information boards on whales and dolphins that are due to be installed by FIG along the Cape Pembroke peninsula hiking trails to further highlight the cetacean ecotourism potential of the area for tourists and locals. Encouraging shore-based whale-watching also addresses one of the main management recommendations in providing a viable alternative to the use of boats and aircraft to view cetaceans, and therefore reduces potential impacts from disturbance and vessel strike.

Spatial distribution of all cetacean sightings recorded during surveys from the Cape Pembroke lighthouse in 2017.

One unexpected result from the project was the notable success in acquiring sufficient good-quality identification images of sei whales to be able to develop a photo-identification catalogue for Berkeley Sound in 2017. This catalogue will be available publicly and will provide a further legacy element to the project in terms of being available for future years for people to compare their sei whale images against.