Cetaceans in the Western Indian Ocean


In early 2019 cetaceans in the Western Indian Ocean and Arabian Seas were the focus of two important scientific meetings. The first was to identify Important Marine Mammal Areas (IMMAs) within the region, and the second, conducted under the auspices of the International Whaling Commission Bycatch Mitigation Initiative, was to look at priority areas in the region for cetacean bycatch interventions.


Important Marine Mammal Areas
Important Marine Mammal Areas (IMMAs) are defined as discrete portions of habitat, important to marine mammal species, that have the potential to be delineated and managed for conservation. The Western Indian Ocean and Arabian Seas IMMA identification workshop took place on 4-8 March 2019. The workshop was held in Salalah, Oman, and involved 38 marine mammal scientists and observers from 15 countries, with several more scientists contributing to assessments and proposals remotely. A total of 55 candidate important marine mammal areas, (cIMMAs) were identified which is the largest number proposed from a single workshop to date. Thirteen areas of interest (AoI) were identified as locations where further research is merited. The experts identified cIMMAs for the Arabian Sea humpback whales, Indian Ocean humpback dolphins and concentrations of Omura’s whale, as well as three different populations of blue whales. The cIMMA proposals are now undergoing peer review, and those that are approved will be added to the eAtlas later in 2019. The preliminary report from the workshop can be downloaded here.


IWC Bycatch Workshop
The International Whaling Commission (IWC) held a technical workshop on Bycatch Mitigation Opportunities in the Western Indian Ocean and Arabian Sea from 8-9 May 2019 in Nairobi, Kenya. The workshop was attended by 50 participants working in 17 different countries. The workshop included a range of presentations on innovative approaches to assessing, monitoring and mitigating bycatch, as well as some hands-on sessions where participants worked together to identify potential bycatch hotspots in the Western Indian Ocean, where further research and mitigation efforts can be directed. The Report of the IWC Workshop on Bycatch Mitigation Opportunities in the Western Indian Ocean and Arabian Sea is available for download here.

It was recognised that cetacean bycatch is generally very poorly documented in the region and that this presents a major barrier to understanding the scale of the issue and making progress towards bycatch reduction. The workshop concluded that a more systematic assessment of bycatch information is critical, particularly for small-scale and medium-scale fisheries. Given the prevalence of small to medium-scale fisheries using passive fishing gears (gillnets, traps, etc.) across the Indian Ocean region, and the lack of financially viable and effective mitigation solutions for these gears, the workshop concluded that further work to develop and trial low-cost and low-tech solutions was urgently needed. The utility of existing tools and approaches for assessing and monitoring bycatch in the numerous small to medium-scale fleets was also recognised, including rapid bycatch risk assessments, remote electronic monitoring and crew-based observer schemes. The workshop concluded that bycatch reduction efforts should aim to apply multi-disciplinary and multi-taxa approaches wherever possible. The workshop resulted in a number of recommendations for collaborative work to reduce bycatch in the region that can be read in detail in the final report.