Two new Reports on cetaceans in the Indian Ocean and Arabian Seas!


Participants to the IWC Workshop on Bycatch Mitigation Opportunities in the Western Indian Ocean and Arabian Sea.  May 7-9, 2019, Nairobi.

This week two new workshop reports have been released, each containing a wealth of valuable information related to conservation of cetaceans in the Western Indian Ocean and Arabian Seas.  The first is the Report of the IWC Workshop on Bycatch Mitigation Opportunities in the Western Indian Ocean and Arabian Sea. It is available for download by following this link  or directly through the IWC archive

This workshop, which was held in Nairobi in conjunction with the IWC Scientific Committee meeting was funded by generous contributions from the Government of France, the US Marine Mammal Commission, the Pew Foundation, the Western Indian Ocean Marine Science Association.  It 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, where further research and mitigation efforts can be directed.  The workshop resulted in a number of recommendations for collaborative work to reduce bycatch in the region.  A few key recommendations are pasted in the table below.

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The second Report of note is the Preliminary report of the Workshop on identification of Important Marine Mammal Areas (IMMAs) in the Western Indian Ocean and Arabian Seas. This report can be downloaded here:

Candidate IMMA proposals drafted during that workshop are in the final stages of review and revision.  Once the final IMMAs and Areas of Interest have passed the independent reviewers and correspondence concluded with those needing further information, the IMMAs and AoI will be placed on the IMMA e-Atlas with background PDFs for each IMMA. Once that is in place, a final report will be issued with the final numbers and list of IMMAs and AoI for the region.

Both workshops involved a number of ASWN members, and allowed them to share their knowledge and expertise, while also learning from ‘neighbours’ working in other parts of the Indian Ocean.  Both workshops also paved the way forward to continued and increased collaboration to address the challenges of protecting cetaceans and their habitat.


ASWN members Dipani Sutaria and Mohammed Moazzam Khan work with IMMA Chair, Erich Hoyt on proposals for Important Marine Mammal Areas in India and Pakistan.


Summary of Recommendations of the IWC Bycatch Workshop:

  • The workshop recommends that governments in the Indian Ocean region establish or strengthen bycatch assessment and reduction programmes as a matter of urgency, with priority on bycatch hotspots areas identified across the region. Associated actions could include rapid risk assessments, on-board data collection, mitigation trials (experimental and existing measures) and/or implementation of effective management measures.
  • The workshop recommends that governments and other relevant stakeholders in the Indian Ocean region carry out cetacean sampling surveys to collect information on species abundance and distribution at national and regional scales and encouraged that this information could be shared with the IWC Scientific Committee.
  • The workshop recommends that the IWC (including through its Conservation Committee) develop and communicate recommendations to governments on the importance of addressing bycatch through policies and other measures that support bycatch mitigation efforts, and of more coherent approaches across government departments with different mandates; and promotes the sharing of information and experience between its contracting members.
  • The workshop recommends that the BMI assist bycatch reduction efforts in the Indian Ocean region, including through:
    •  raising awareness and prioritisation of addressing cetacean bycatch in small to medium-scale gillnet fisheries through its engagement with member countries and other IGOs and NGOs;
    • developing a regional road map for bycatch reduction (including assessment, monitoring and mitigation) in collaboration with other relevant bodies (e.g. FAO, IOTC, CMS, national governments);
    • providing technical assistance to countries to assess different aspects of cetacean bycatch (e.g. monitoring, assessment, mitigation) and support and promote multidisciplinary monitoring (e.g. social science techniques, economics) and mitigation approaches, including though capacity building;
    • exploring means of more consistent and sustainable approaches for funding of bycatch mitigation efforts.
  • The workshop recommends that bycatch reduction efforts employ a multi-disciplinary and multi-taxa approach at local, national and international scales.
    National Governments in the Indian Ocean region; scientific research community;
  • The workshop recommends that the BMI provides technical assistance to governments and other relevant stakeholders within the Indian Ocean region in the design of experimental mitigation trials that are both scientifically rigorous and which supports the livelihoods of fishing communities, as far as is possible.
  • The workshop recommends that the IWC (through the BMI and through its conservation and scientific committees) assist efforts to communicate scientific and conservation advice to decision makers in collaboration with other inter-governmental organisations and non-governmental organisations.
  • The workshop recommends to governments and other relevant stakeholders in the Indian Ocean region that bycatch monitoring and reduction efforts use (where appropriate) crew-based approaches for collecting data on bycatch and mitigation measures (including where observer programmes are not feasible due to the size of vessel, the large numbers of small and medium-scale fishing vessels, trip length, safety concerns etc).
  • The workshop recommends that the BMI assist national efforts by developing a toolbox of more effective tools for communication with fishing communities and associations including the promotion of fisher-exchanges to share experiences of bycatch mitigation efforts and efficacy.
  • The workshop recommends renewed efforts by the research community and fisheries technologists in the research and development of low-cost bycatch mitigation and monitoring solutions, particularly for gillnet fisheries and the scaling-up of testing of existing measures (e.g. lights and acoustic deterrents, and experimental low-tech tools) in different fisheries and locations.
  • The workshop recognised the importance of capturing socio-economic information as part of a holistic and multi-disciplinary approach, and therefore recommends to countries that monitoring and mitigation programmes should also integrate collection of economic data (CPUE, catch value etc) to be collected and analysed alongside bycatch information.
  • The workshop recommends that governments in the Indian Ocean region consider pro-active reassurance to fishers that there will not be negative consequences in response to reporting bycatch and furthermore recommends to use fisher reported data for monitoring and bycatch management purposes rather than for compliance and enforcement.
  • The workshop recognised the growing importance of REM methods and the possibility for cost-effective monitoring at a fleet-scale, and therefore recommends that governments and relevant stakeholders in the Indian Ocean region engage in trialling REM approaches for bycatch monitoring, including low-cost methods for small and medium-scale vessels (and in other vessels as appropriate).
  • The workshop recommends that the BMI provide technical assistance upon request on the REM systems available and their applicability to a specific situation.
  • The workshop concluded that there was an important need to raise the profile of cetacean bycatch and promote bycatch reduction efforts within the context of RFMOs, and specifically within the Indian Ocean and it therefore recommends that:
    • The BMI engage more formally and more regularly with the IOTC, the South West Indian Ocean Fisheries Commission (SWIFOC) and other relevant RFMOs, including in collaboration with other relevant organisations, to encourage more discussion and action of cetacean bycatch monitoring and mitigation in the fisheries under their management. This could be achieved through direct observer status and/or the appointment of regional representatives/contacts to maintain an overview of relevant RFMO meetings and opportunities to participate and/or present information.
    • IWC Contracting Governments undertake further efforts to improve the quality and quantity and reliability of cetacean bycatch data reported to the IOTC and to other bodies (including the IWC national reports) and for small-scale fisheries.
    • Bycatch Mitigation Initiative; IWC Conservation Committee; IWC Secretariat; National governments in the Indian Ocean region
    • That the BMI support where appropriate contracting and non-contracting governments in the exchange of cetacean bycatch information and experiences between neighbouring countries and support the development of transboundary approaches including through BMI engagement with RFMOs
    • That the BMI explore its potential to assist countries in fulfilling their reporting requirements under IOTC, as well as the potential for greater sharing of information on bycatch between the IWC and FAO/the RFMOs.

Blue Whales in Oman; the Sultanate’s most diverse marine mammal hotspot just got hotter!

The following is a blog shared by ASWN member Andy Willson that provides some insight and inspiration for cetacean conservation efforts off the coast of Oman, based on recent surveys conducted in the Dhofar region.  The results of these surveys were also presented to the International Whaling Commission’s recent Scientific Committee meeting in May, and the more scientific version can be found here.  But for a more informal and entertaining read, pour yourself a cup of tea, and sit down and Enjoy the following!

Blue whale medley April 2019

A blue whale photo medley courtesy of Five Oceans Environmental Services, Oman.

The Five Oceans Environmental Services (5OES) team based in Muscat, Oman spent early April 2019 conducting a cetacean survey off southern Oman. Following on a hot trail of discovery, the recent survey documented blue whales conspicuously feeding in this area for the first time. Maturing in step with the receding hair-lines of its once young explorers, scientific evidence from this study site is beginning to prove that it is one of the most diverse, exciting and confusing areas for cetacean research in the Northern Indian Ocean (NIO).

Formalised cetacean research in Oman took off in the late nineties/early 2000s in response to growing global interest in records of humpback whales off Oman’s coast. Hundreds of kilometres of coastline lay waiting to be explored by a ‘green’ team of early career researchers armed with a shaky old 4WD, a retired fishing boat, a point and shoot 35mm camera and a stash of donated baked beans and pitta bread. Initial records pooled from merchant navy records, incidental sightings and soviet whaling records from the mid-60s provided evidence that the humpbacks found off the coast could be part of a unique and isolated population. With an astonishing talent for establishing scientific collaboration and busking for support, the team’s efforts were rewarded in 2008 with formal recognition that Oman’s humpbacks were indeed an isolated population of humpbacks, and so graduated from their previous designation by the International Whaling Commission (IWC) of ‘Population X’ into a more formal title, ‘Arabian Sea humpback whales’. Years of genetic study, involving biopsying whales to collect tissue samples for subsequent DNA analysis in the lab had proved that the whales were totally different from all other humpbacks in the world and had been isolated for an estimated 70,000 years. At the same time, photo-ID mark-recapture population assessment provided estimates of fewer than 100 animals residing off Oman. This prompted an urgent requirement to answer more questions relating to conservation management. More complex ecological investigations began to emerge in the form of species distribution modelling, round the clock acoustic monitoring and, ultimately, satellite tracking. These new methods required refocusing the team’s very limited survey resources into just two favoured study sites.

Early on, one of these favoured study sites on the corner of the Hallaniyats Bay in southern Oman began to yield results beyond expectations. Almost every survey the area resulted in encounters with new species or observations of new behaviour. At the last count the team which includes the Environment Society of Oman and Ministry of Environment and Climate Affairs had documented 18 of the 21 species known to Oman. At first look the guest list looks like a collection of misfits – representing some of the most deep diving and wide ranging of offshore species alongside those that hug the coast so tightly they could easily benefit from legs:  Indo-Pacific common dolphins (Delphinus delphis tropicalis), common bottlenose dolphins (Tursiops truncatus), spinner dolphins (Stenella longirostris), Indo-Pacific bottlenose dolphins ( Tursiops aduncus), rough-toothed dolphins (Steno bredanensis), Indian Ocean humpback dolphins (Sousa plumbea), Risso’s dolphins (Grampus griseus), false killer whales ( Pseudorca crassidens), killer whales ( Orcinus orca), dwarf sperm whales (Kogia sima), melon-headed whales (Peponocephala electra), short-finned pilot whales (Globicephala macrorynchus), Cuvier’s beaked whales (Ziphius cavirostris), sperm whales(Physeter macrocephalus), Bryde’s whales (Balaenoptera edeni), Arabian Sea humpback whales (Megaptera novaeangliae)and blue whales ( Balaenoptera musculus cf indica).

Evidence from 17 years of work at this site has recently been compiled to nominate the study site as a candidate for one of the world’s most ‘Important Marine Mammal Areas’ (IMMA). This was proposed at a workshop organised by the IUCN Marine Mammal  Protected Area Task Force in March 2019 in Salalah, Oman.  Self-promoting, the site ticks almost every criterion in the book for what is required to define an important area for whales and dolphins, from the high diversity of species to its quirky isolated and endangered residents. One of these residents, ‘Quasimodo’ a particularly hump-backed female Arabian Sea humpback whale with a spinal abnormality made a sneak appearance as a few members of the task force team passed through the site in mid-March on their way out of the IMMA workshop.


Quasimodo, a particularly ‘humped’ humpback whale, photographed in Dhofar in 2011.  Courtesy of the Environment Society of Oman.

The high diversity of cetaceans with both coastal and offshore habitat preferences is thought to be related to the unique bathymetric and oceanographic conditions. The coastline on one side of Hasik is characterised by a mountain escarpment which plummets down to the continental slope offshore, whilst to the other side is a large shallow embayment of continental shelf. The interface between these seafloor features generates strong, sustained currents that promote year round pulsing of upwelling nutrient-rich waters from the deep ocean. With the onset of the southwest Indian Monsoon during the summer months, the upwelling along the southern coast of Oman is amplified, transforming the space from a sub-tropical to a temperate oceanic regime. Only accessible to the research team outside of this turbulent season the humpback whales have been observed consistently in the area every winter and spring. Singing (related to breeding) is the popular pastime of a group of approximately six male humpbacks that are consistently re-encountered at the site year on year. More unconventional activities have also been observed, such as switching between competitive breeding related behaviour and ‘bubble-net’ feeding just breaths apart. Such habitat use is considered a unique trait of this non-migratory population where social and dining engagements can all be serviced in the same time and space. Humpback whale populations in all other parts of the world typically have such delights separated by months of travel and thousands of kilometres as they migrate between polar feeding areas and tropical breeding grounds.

Dhofar map with sightings

The coastline on one side of the Hallaniyats Bay is characterised by a mountain escarpment which plummets down to the continental slope offshore, whilst to the other side is a large shallow embayment of continental shelf. This figure shows that unique bathymetry and the species encountered in the Hallaniyats Bay region, southern Oman between March 2018 and April 2019 (courtesy of Five Oceans Environmental Services).

The presence of a smaller lesser known baleen whale, the Bryde’s whale, has also been documented on almost every survey in the area. This species seems to specialise in taunting the research team. During the last survey, Bryde’s whales pulled off their best trick by breaching in front of the teams’ campsite on a number of occasions and then running off to hide (although we eventually managed to catch up with them). As much as a mystery as the blue whales, this tropical whale is notoriously difficult to study due to its stealthy speed and preference for surfacing just where the research boat isn’t. As such it lies high on the list of miscreants for the research team to investigate.

Blue whales are infrequently observed in Oman and were documented off the survey site for the first time in 2011. Their presence elsewhere in the northern Indian Ocean (e.g. off Sri Lanka) is better known, although the taxonomy and population structure remains unresolved. Echoing the Arabian Sea humpback whale enigma, the jury is out on the details of their population affinity and range. Are they unique and isolated to the NIO or are they part of a larger more wide-ranging population in the Indian Ocean? Recent literature cites blue whales found in the NIO as either a subspecies of a smaller form of blue whale known as pygmy blue whales found across Indian and Pacific Oceans (Balaenoptera musculus brevicauda – Ichihara, 1966), or, intriguingly as another unique whale, the Indian Ocean blue whale (Balaenoptera musculus indica – Blythe, 1859). The ‘indica’ sub-species designation identifies the taxonomy of this smaller form of blue whale with a more restricted geographical range, not dissimilar to the Arabian Sea humpback. Efforts to resolve this impasse on population affinity and range have so far been painstaking. To approve the ‘indica’ form the evidence needs to demonstrate geographical isolation and significant biological differences. This is where the story slides from blue to grey.

To date only two genetic samples have been processed from blue whales in the NIO and the results demonstrated no discernible difference in the DNA sequence between pygmy blues found in the southern Indian Ocean and their counter-parts to the north. However, the sample size was considered too small to draw reliable conclusions. Study of historical whaling data shows that blue whales encountered in the NIO are 0.5m shorter than southern blues; a relatively small difference. However, the cookie cutter shark bites observed by whalers on blue whales taken in the southern Indian Ocean have not been observed on blues to the north of the equator. Whalers have also described a gap in the central Indian Ocean where very few blue whales were ever observed, suggesting there may be no movement north and south across the equator. With song often used as a descriptor for placing geographical limits on the population structure the ‘isolationist’ theory is further supported by the unique song or call types recorded off Sri Lanka and the Chagos Archipelago but never further south in the Indian Ocean. Meanwhile, sightings and strandings data show blue whales to be present in the Indian Ocean year-round. Recent re-evaluation of whaling records has revealed no discernible seasonality to  the reproduction of blue whales in the NIO, where-as the breeding season of blues in the SIO is understood to occur only in the austral winter.

Last year a new twist emerged with the Oman team reporting to the IWC Scientific Committee a completely new baleen whale song type. The song was recorded in 2012 at the Hasik study site with call attributes that imply the source of the ‘baritone’ vocalisation was most likely from a blue whale.

With that as background, it’s no wonder that we were reeling with expectation as we bounced our way towards a sighting called-in by the shore-based team on day three of our survey in April. This was the latest in the season we had been on survey at the site for many years. Multiple tall blows could be seen from the boat through the building Force 5 seas with momentary glimpses of a broad back that slowly transformed into the unmistakable mottled steel grey blue of a blue whale, rolling into a dive. Thinking we were in for a brief sunset encounter with a transiting ‘5 O’clock whale’ the team moved into position to collect photo-ID data before being left trailing in a pool of bright orange faeces as the whale dove out of site with its tail high in the air. The fluking behaviour is not considered a common behaviour of blue whales, but is well documented off the coast of Sri Lanka on feeding aggregation sites. However, the bright orange faeces was certainly a sign of recent feeding and the team bagged a sample followed by a well-timed biopsy on the next surfacing of the animal. Over the following 2 days we documented at least another four animals performing regular dives with a couple of minutes surface time followed by 10-14 minute dive time intervals. The whales ranged in length between 12m and at least 18m. In total five biopsies and two separate faeces samples were gathered, together with a collection of 100’s of photos for ID use. The biopsy samples are the first to have been taken from live blue whales in Oman: the two previous DNA samples came from stranded whales. The results are accompanied by referenced photo-ID images of the biopsy takes.

Blue whale dive sequence

As before this special corner of the Indian Ocean has produced the unexpected. The game is now on to get the biopsy and faeces samples sequenced and photos processed to ready them for comparison with other catalogues in the Indian Ocean. 2019 could be the year we get closer to unravelling the mystery of blue whales in this part of the northern Indian Ocean. Or will these investigations just throw up yet more questions? Which-ever way this pans out the team is aware there is far more work to be done to help understand, and ultimately safeguard, this important corner of our blue planet.



Collaboration for Killer Whales in the Northern Indian Ocean

Still images extracted from video taken by fishermen on May 14 2017, near to Hendorabi Island, Hormozgan Province, Iran.

Two recent publications have  highlighted the value of regional collaboration and broad-scale (social) networking for cetacean research and conservation in the Northern Indian Ocean and Arabian Seas.

The first is a newspaper story that tells the fascinating tale of a sighting of killer whales made by an Emirati businessman on his way home from a fishing competition. A video of the sighting posted on social media drew the attention of local researcher and ASWN member, Ada Natoli, founder and director of the UAE Dolphin Project. She has been using social media to support a cetacean sightings and strandings network in the UAE.  The video footage was shared with with Georgina Gemmell, a scientist who coordinates the Northern Indian Ocean Killer Whale Alliance (NIOKWA), and other scientists in the region. Collectively they were able to determine that these whales were members of a group called ‘Pod 11’ who were first observed off Abu Dhabi in 2008, and then seven years later in Sri Lanka. You can read more about this sighting in the original newspaper article here.

The second publication is a journal article published today in ‘Zoology in the Middle East‘.  This short communication documents three killer whale sightings made in Iranian waters in 2017 and 2018. These were also sightings reported by non-scientists, recorded with video using smart phones, and then shared with cetacean researchers.  ASWN members from Iran’s Plan for the Land Society were able to collaborate with other scientists in the region, as well as the NIOKWA to analyse the video footage and identify at least one individual whale – a female or young male- who was recognisable and present in two of the 3 sightings.  Although no matches were made between this identified whale and other individuals in the NIOKWA catalogue, these three sightings from a region where so little is known about killer whale distribution and movements offer valuable insights where no previous data existed, as well as motivation to learn more about this intriguing species.


ASWN members participate in workshop to identify Important Marine Mammal Areas in the Western Indian Ocean and Arabian Seas



 Workshop participants in Salalah, 4 March 2019

In the week of March 4th-8th, a number of ASWN members participated in a workshop to identify Important Marine Mammal Areas (IMMAs) in the Western Indian Ocean and Arabian Seas.   The workshop was the 5th of its kind and hosted 38 marine mammal scientists and observers from 15 countries.

An extraordinary 55 candidate important marine mammal areas, or IMMAs, were identified, along with 13 areas of interest (AoI) which may be considered potential future IMMAs pending further research. Of the 55 areas identified as candidate IMMAs, a number were in the Arabian Sea and surrounding waters, focusing on important habitat for Arabian Sea humpback whales, as well as other endangered and vulnerable species such as Indian Ocean humpback dolphins and blue whales.

IMG_9297 6

A summary of the results of the week’s work – groups drafted detailed proposals for 55 candidate IMMAs and reviewed an additional 13 Areas of Interest.  Notice that the Arabian Sea, particularly habitats known to be important for Arabian Sea humpback whales are under consideration.  These proposals will now be reviewed by an expert panel.

The Oman workshop follows successful Task Force IMMA regional workshops in the Mediterranean, Pacific Islands, Northeast Indian Ocean-Southeast Asian Seas and the Extended Southern Ocean in 2016-2018, but 55 candidate IMMAs is a record total to date for a single region. Sponsored by the Global Ocean Biodiversity Initiative through the German Government’s International Climate Initiative (GOBI-IKI), the Task Force has adopted as its mandate the mapping of habitats for the 130 species of marine mammals—cetaceans, pinnipeds, sirenians, otters and the polar bear—across the world ocean.

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. They are not marine protected areas but rather layers with useful information on marine mammals that can be used by governments, intergovernmental organisations, conservation groups, and the general public for spatial planning, environmental impact assessment, or other area-based management tools.


ASWN members Dipani Sutaria and Moazzam Khan work with IMMA Task Force Chair, Erich Hoyt to draft proposals for IMMAs off the coasts of India and Pakistan.

Workshop participants spent the week working collaboratively on the drafting of detailed proposals for the areas that were identified, providing evidence on how each area meets the rigorous criteria defined by the IMMA Task Force. The candidate IMMAs will now be sent to an independent review panel, undergoing a process of peer review much like that used in scientific journals. Candidate IMMAs that pass review will be placed on the IMMA e-Atlas, and can be used for conservation planning. Those without sufficient evidence will remain as Areas of Interest, but will still be reflected in the e-Atlas. Final results from the panel are expected to be posted online later in 2019. The collective expertise, energy and commitment of the scientists, gathered in the inspirational setting of Dhofar have made this technical and scientific exercise a great success.

The creation of a network of IMMAs represents a cost-effective approach to conservation. Marine mammals are, in many ways, catalytic species. As top predators in the marine environment, they can serve as an indicator of an ecosystem’s overall health, and as charismatic flagship species, they are often the focal species for the creation of marine protected areas around the world.  Calling more attention to the habitats that are important for marine mammals, and making it easier for stakeholders to take marine mammal conservation needs into account, can ultimately lead to the protection of less popular or well-known organisms, communities or habitats.

For more information on the Task Force and IMMAs, see

Or contact Erich Hoyt or Giuseppe Notarbartolo di Sciara


ASWN Flukebook data platform ready for launch!

flukebook logo

The long-awaited regional data platform is ready for use!  After months of intense work to import and refine all of the functions required to deal with a large volume of cetacean survey sightings data from Oman, we are now ready for Arabian Sea research groups with ongoing research products and/or historical data comprising cetacean sightings and/or photographs to request accounts and begin uploading data.
Instructions for how to use the data platform can be found on a new page of our site dedicated to the ASWN Flukebook.  Two training videos demonstrating how matching and sighting searches can be conducted provide the best possible insight into how the platform works.

What is the ASWN Flukebook?

ASWN has partnered with Wild Me to create an Arabian Sea regional whale and dolphin database. was originally developed as an open-source online tool to assist with digital matching of humpback whale and sperm whale tail fluke images, using Computer Vision matching technology.  This video demonstrates how that technology works.  While Flukebook started as a platform to facilitate photo-identification, the collaboration with ASWN and other research groups such as the Indian Ocean Network for Cetacean Research (Indocet) has allowed Flukebook to expand and improve, adding elements that allow archiving and analysis of almost every type of data collected during the course of directed cetacean research including:

  • computer vision algorithms

    Original research by the multi-institution Wildbook team (see has created multiple methods of identifying individual humpback flukes repeatedly. Shown here is the CurvRank algorithm, which matches flukes based on their unique trailing edges. CurvRank is one of two algorithms used in Flukebook. Photos courtesy Wild Me

    the date, time, location, species, group composition, behaviour, and human activities associated with a whale or dolphin sighting of any species;

  • Photographs suitable for individual identification (tail flukes, dorsal fins), along with associated data on photo quality and distinctiveness, required to filter data for mark-recapture analyses;
  • Data on genetic sampling and satellite tagging of individual whales;
  • Filtering and export functions that allow users to analyse data geographically, temporally, by species or any other data field, and export results for mapping, mark-recapture analyses, or other uses

Why Flukebook?

ASWN chose to partner with Wild Me in large part because Flukebook is an open- source platform used by multiple cetacean research teams around the globe.  Through these collaborations, Flukebook is constantly improving and updating the features it offers.   For example, the Indian Ocean Network for Cetacean Research (Indocet) is also using Flukebook for its regional humpback whale photo-identification data platform.  Close collaboration between the ASWN and Indocet has allowed joint development of new features and improvements, many of which will become available in the coming months.  Research teams working with other species, such as bottlenose dolphins, sperm whales, and right whales are also helping to foster the development of new computer vision matching algorithms for these species.

ASWN was also impressed at the level of data security offered by Wild Me and the Flukebook team.  While the data platform is designed to facilitate collaboration and comparison of data through the use of a common online data platform, users who upload data retain complete control of that data.  Data that a user has uploaded will be invisible to other users unless a collaboration has been initiated, backed by clear data sharing agreements.

We look forward to this next phase of regional collaboration.  Please feel free to contact Gianna Minton (<>) or Drew Blount (<>) with any questions or requests for additional information.

ESO Completes Arabian Sea Humpback Whale Acoustic Analysis: A Sound is Worth a Thousand Words

الحوت الاحدب، Hupback Whales

Humpback whale off the coast of Oman (copyright Environment Society of Oman).  Male humpback whales sing complex songs underwater. Passive recorders stationed in various locations off the coast have confirmed that Arabian Sea humpback whales sing different songs to their Southern Hemisphere Indian Ocean counterparts, and provided insight into the seasonal variations in humpback whale song in different locations.  One surprise finding includes the detection of Southern Hemisphere singers at one location during the Omani summer, when Arabian sea whales were not singing.

The following is a press release from the Environment Society of Oman:

The Environment Society of Oman (ESO) in partnership with New England Aquarium (NEA) have recently finalised their findings on a two-year acoustic dataset on the Arabian Sea Humpback Whales (ASHW). The aim of the project was to document spatial and temporal distribution of Arabian Sea humpback whales in the region, investigate singing behaviour and geographic variation, as well as assess potential threats to the population posed by anthropogenic noise. The project was conducted off the coast of Oman in Hallaniyats Bay and the Gulf of Masirah from 2011 to 2013.

Currently listed as Endangered by the IUCN Red List, the Arabian Sea humpback whale has a population estimated to be less than 100. The study was undertaken as a matter of urgency and as a means to identify conservation solutions by acoustically assessing the presence and seasonality of whales, and monitoring the amount and effects of ambient noise on whales. Measuring sound is a critical factor for cetaceans as hearing is their primary sense used for foraging, migration and reproduction, and impairment of communication and hearing can have serious population consequences. The study involved three components, seasonal and geographic detections of humpback whale vocalizations off Oman, characterizing ambient noise in the monitored regions, and comparing song structure variation across the western Indian Ocean, with ground-breaking results.

Suaad Al Harthi, Executive Director at the Environment Society of Oman, stated “I would like to thank our sponsors Shell Development Oman for funding and supporting this project. The research and the acoustic analysis has revealed valuable information about the Arabian Sea humpback whales, confirming the areas that are important to them, and the potential impact of noise pollution. Our conservation program is ongoing and with the support of local and international partners we are able to develop and address conservation concerns.”.

The detection of whale presence involves the highly effective method of Passive Acoustic Monitoring (PAM) for assessing distribution across broad spatial and temporal scales. From continuously recording at three sites for two years, and a total of 1,369 acoustic recording days, it was discovered that the population utilizes both the Gulf of Masirah and Hallaniyat Bay for breeding. However, the Hallaniyats, had more frequent singing of Arabian Sea Humpback Whales, suggesting it may be a more important breeding area. Nevertheless, the study clearly indicated that both locations are considered “hot spots” for the population. There was also a shift in distribution from south to north into the Gulf of Masirah towards the end of the breeding season, apparently as the population shifted into the non-breeding season.

Muna Al Shukaili, General Manager of External Relations and Social Investment Lead at Shell Development Oman said, “We are proud to sponsor this initiative and help raise awareness on the impact human activities have on the Arabian Sea humpback whales. This is the reason we have collaborated with ESO and we hope that a lasting solution can be found for these vulnerable mammals. Preserving the ocean biodiversity is part of Shell’s commitment towards the environment and sustainable development in Oman.”

Andrew Willson, Senior Marine Consultant at Fives Oceans Environmental Services, said, “This study has been a break-through for the team’s work in the Arabian Sea given that the sophisticated equipment and subsequent analysis has allowed us to monitor for the occurrence of whales within their critical habitat almost year round. This significantly extends knowledge gained from conventional small vessel surveys conducted along the coast of Oman over the last 18 years. The technique has capitalised on one of the key traits of marine mammals; that they are highly dependent on communication through acoustics for their survival”.

Considered the most consequential finding of the overall study in the context of conservation, the analysis of ambient sound sought to determine potential threats in each location.  Using sophisticated standardized analyses, biological, physical and anthropogenic noise sources were assessed to provide a profile of the “soundscape” over time and across frequencies.  Areas around Port Duqm with elevated anthropogenic noise appeared to have a decreased level of humpback whale singing activity, suggesting that whales were either disturbed or their song displays were masked in vicinity of the port. This indicates that further assessment and action in the preservation of the Arabian Sea humpback whale is highly advisable.

Dr. Salvatore Cerchio, the Project Lead Researcher from the New England Aquarium said, “In-depth analyses and findings around the world on the impact of loud anthropogenic noise sources on whales are compelling. This type of noise pollution is widely recognised as having a negative effect on the marine life and marine ecosystems alike. Our findings off Oman indicate that the same processes are likely at work in the Arabian Sea, and could be a contributor to the low number of Arabian Sea humpback whales living off the coast of Oman. What we need to do now, is work together with governments towards putting in place a marine noise policy and learn how to better monitor and manage it.”

The final section of the acoustic analysis involved an oceanic comparison of humpback whale songs that benefited from a large-scale international collaboration, with contributions from researchers with song samples from several regions, including National Institute of Ocean Technology, India; Globice, Reunion Island; and Accademia del Leviatano, Italy, working off the Comoros Islands.  The song structure of humpback whales off Oman were compared to samples from the west coast of India and from the Southwest Indian Ocean (SWIO) to assess isolation of the population from Southern Hemisphere populations, and to describe their singing behaviour. Analysis indicated several key findings, revealing that songs from Oman and India across the Arabian Sea appeared to be very similar, but that the ASHWs song remained distinct and consistently different from the SWIO song across the years. This finding reinforces our understanding of isolation of the ASHW as previously indicated by genetic and photographic studies.

However, two surprise findings were also of great interest. Unlike humpback whale song around the world, which changes progressively each year, the song of whales off Oman changed very little across three years, remaining virtually the same during the study period.  Moreover, it was found that some Southwest Indian Ocean animals moved into the Arabian Sea during the Omani summer when the ASHWs were not singing; however, the ASHWs did not learn or pick up there song as happens elsewhere in the world.  The overall conclusion drawn from this study of singing behaviour is that behavioural isolation mechanisms may exist to prevent the mixing of the Arabian Sea population with Southern Hemisphere animals.

In summary, the acoustic study of the Arabian Sea humpback whales has provided many new insights into the behaviour and conservation of the population. Only through in depth studies, and large-scale international collaborations as demonstrated in this project, will the recovery of the Endangered Arabian Sea humpback whale population be assured.

press coverage for this report includes:

You can download copies of the reports on this study that were presented to the Scientific Committee of the International Whaling Commission in 2016 and 2018.

New Indian Ocean Cetacean Identification Cards available

IOTC cetacean Identification cards image

The IOTC has produced a valuable new resource for identification of cetaceans in the Indian Ocean.

A great new resource has just become available to all those working with cetaceans or cetacean-fisheries interactions in the Indian Ocean and Arabian Sea.  The Indian Ocean Tuna Commission (IOTC) has been working on the development of a set of cetacean identification cards for Indian Ocean Fisheries.  These have been finalised and released for free download.
The cards are available as part of a series of resources and ID cards produced and available through the IOTC.  The Cetacean ID cards were designed by ASWN member, Gill Braulik, and their development was supported in part by the Marine Mammal Commission, which has also supported the ASWN and its various initiatives. The IOTC website contains the following text and link to download the PDF:

‘The IOTC Secretariat has finalised the development of field identification cards for cetaceans in the Indian Ocean. The cards were developed by an independent consultant, Dr Gill Braulik, in collaboration with the Working Party on Ecosystems and Bycatch at the request of the Scientific Committee. This guide is a tool for the identification of the main cetacean species interacting with pelagic fisheries for tuna and tuna-like species. It is a small-sized, waterproof, pocket guide intended for use onboard vessels by fishers and scientific observers to improve the quality of the data collected in the IOTC Area of Competence.The identification cards were produced in English and will shortly be published and printed in French and other priority languages identified by the Working Party on Ecosystems and Bycatch thanks to support from the Marine Mammal Commission. Please send enquiries regarding hard copies to

You may download the identification cards from the following here. or from:

Image from IOTC Cetacean ID cards

Example of one of the species ID cards produced by the IOTC.   A limited number of hard copies (laminated and pocket-size for convenience on board vessels) are available from the IOTC Secretariat. It is also available for download in PDF format.