Arabian Sea whales at the 2020 virtual IWC Scientific Committee Meeting

Arabian Sea whales once again featured prominently in discussions of the International Whaling Commission’s Scientific Committee, which was held between May 11th and 24th, 2020.  The meeting was originally scheduled to take place in Cambridge, UK, but for obvious reasons had to shift to a virtual format instead.  In order to accommodate different time zones around the globe, live discussions were limited to two-hour time slots each day, during which parallel Zoom sessions were conducted for different subcommittees.  Many members of the ASWN were able to participate in this virtual format, and some of the key documents and outcomes are highlighted below:

  • As most of you are aware, network members collaborated to produce the annual ASWN Progress report (SC_68b_CMP_11_Rev1). This report summarised ASWN activities over the past year, highlighting progress of individual projects within the network (Oman, the UAE, Iran, Pakistan, India and Sri Lanka), and the extension of the CMS Concerted Action for Arabian Sea humpback whales.  This was complemented by a report submitted by the IWC’s Standing Working Group on Conservation Management Plans (CMP), which included an update on progress toward a joint IWC-CMS CMP for Arabian Sea humpback whales (SC_68B_CMP_17).
  • WWF Pakistan prepared an annual update of the whale sightings reported by the crew-based observers working on the tuna gillnet fleets operating out of Karachi.  This report is available as SC_68B_CMP_08 .
Compiled Megaptera sightings

Map showing all Arabian Sea humpback whale sightings reported by the WWF Pakistan Crew-based observer programme between 2015 and 2019.

  • The team from Oman submitted a report on the visual health assessment of ASHW off the coast of Oman, a project that was funded through the IWC SC in 2018.  This report (SC_68B_CMP_16_rev1) highlighted a relatively high prevalence of tattoo-like skin disease in the population, as well as evidence of ship strikes and entanglement scarring.
  • The Oman team also shared the results of a preliminary study using unoccupied aerial systems (drones) to assess the body condition of ASHW in Oman.  This work was conducted with Fredrick Christiansen of Aarhus university and was presented as SC_68B_CMP_23_rev1.
  • Sal Cerchio and colleagues shared a paper that has been submitted to a peer reviewed journal, providing evidence for a new blue whale song in the Indian Ocean termed the ‘Oman song’.  It was submitted to the meeting as SC_68B_INFO_28.
  • The Flukebook team submitted a paper that includes updates on features being added through collaboration with the Indocet and ASWN teams.  This also includes information about multiple new species for which ‘computer vision’ matching algorithms are now available (SC_68B_PH_06). The Flukebook team also collaborated with Happy-whale to provide a side-by-side comparison of the two photo-ID platforms, which is very helpful (SC_68B_PH_01).
  • A group of researchers working on Sousa plumbea (Indian Ocean humpback dolphins) have collaborated to provide a training dataset of photos that the Flukebook team will now use to develop computer-vision matching algorithms for this species (SC_68B_SM_05).
body condition figure

Aerial photograph (video still frame) of an adult ASHW, showing the location of the body length (purple line) and body width (yellow lines) measurement sites. The picture was extracted from the custom-programmed Graphical User Interface developed by Dawson et al. (2017). Note that this individual also has extensive lesions associated with tattoo-like skin disease.

 

 

Although time for discussion was limited, the papers presented raised some interesting questions and a number draft recommendations.  These are taken from the draft report, which is not yet final, and thus wording could be changed:

The Committee reiterates that Arabian Sea humpback whales are a priority candidate for a CMP (IWC, 2019a, p.31) and recommends that the IWC Secretariat and SWG-CMP continue efforts with Oman and India towards development of a CMP in partnership with CMS, which already hosts a Concerted Action for the population. It commends the efforts of scientists within the region and especially the Arabian Sea Whale Network to develop a strong scientific basis to guide the development of a CMP and recommends continuation of research presented at this meeting and the network’s regional collaboration.

Furthermore, the Committee:

(1) welcomes the measures put in place by the Ministry of Environment, Forests and Climate Change, India and the coastal State Governments in India along with local research teams, to promote research, awareness-raising, capacity building and bycatch reduction, and offers technical and scientific support for these efforts where appropriate;
(2) recommends that the work of the crew-based observer programme in Pakistan (SC/68B/CMP/08) continue, if possible mapping fishing effort as well as sightings, and that it be replicated throughout the region where possible, especially in areas where systematic cetacean surveys are not feasible;
(3) encourages continued collaboration between the Pakistan observer programme and the IWC Bycatch Mitigation Initiative (BMI), and also encourages broader collaboration between relevant national governments, researchers and the BMI including through pilot projects on bycatch management, knowledge exchange or requests for capacity building initiatives.
(4) recommends that the use of passive acoustic monitoring to document whale presence and to analyse song be continued in Oman and on the west coast of India and commences off the Sindh and Balochistan coasts of Pakistan, making every effort to ensure simultaneous recordings in all three counties, so that song comparisons can be made across the Arabian Sea;
(5) recommends the continued use of unmanned aerial systems (UAS) and other photographic methods (systematic assessment of images for evidence of disease, epizoites and anthropogenic scarring) to assess body condition and health of ASHW off the coast of Oman with the objective of adopting these metrics as proxy indicators of some of the key ecological attributes related to on-going population trend assessment and conservation planning for ASHWs;
(6) recommends that fishing effort and location of gear that may cause entanglements of ASHW are more accurately mapped throughout ASHW range, especially in the most dense and critical habitat, to assess co-occurrence and risk, in order to better inform mitigation measures;
(7) recommends that a comparative study be conducted between the Oman ASHW catalogue and other Southern Hemisphere Indian Ocean catalogues to assess prevalence and coverage of barnacle scarring and colonization, to determine whether this can be used as a proxy measure for distinguishing ASHW from SH whales.

Three funding proposals were submitted to continue acoustic monitoring for humpback and blue whales off the coasts of Oman and India, and to map human activity as well as carry out more UAS work to assess ASWH body condition off the coast of Oman. These proposals were supported by the Scientific Committee and will be sent to the Commission for endorsement by ‘post’ in the coming weeks.

Due to COVID 19, there will no Commission meeting in the autumn as originally planned. Urgent decisions will be dealt with by ‘postal votes’, and the meeting will take place in September/October 2021 instead. As such, the next IWC Scientific Committee meeting in spring 2021 will be labelled IWC/SC 68C.  We hope that meeting will be able to be held in person in Bled, Slovenia, as planned, and that it will provide an opportunity to assess progress within the network, and make more valuable connections with researchers around the world.