Pacific Scientists publish first sighting of pygmy sperm whale in Fiji

[Pacific Environment Weekly] Scientists and Researchers from the University of the South Pacific (USP), published the first record of a sighting pygmy sperm whale in Fiji in the Journal of the Australian Mammal Society earlier this year. PhD Candidates Rufino Varea, Kelly Brown, and Jasha Dehm along with Research Fellow Dr. Brian Stockwell and Aquaculture Lecturer Dr. Chinthaka Hewavitharane utilized social media in the historical study. 

In July 18th 2020, a pygmy sperm whale washed up at the Natovi Inter-Island Landing in Fiji. Locals posted pictures and videos of the whale on Facebook and tried to help it return to sea. The co-authors, seeing the opportunity to track the event, followed up and recorded it as the first pygmy sperm whale, or Kogia Breviceps, sighting in Fiji. 

Co-author Dehm who is a PhD student studying coastal hydrodynamics and its influences on coastal marine communities, spoke to Pacific Environment Weekly regarding their published findings. Dehm said that although they did not specialize in cetaceans (aquatic mammals) and were not actively searching for this event, once they realized it wasn’t a common whale they decided to investigate further.

“We took all the morphometric measurements as is standard measure during stranding events. We later realised that there was no substantiated record of either kogia species within Fiji waters (only at genus level), and thus decided to record this stranding event as Fiji’s first confirmed record for kogia breviceps,” he said. 

The paper notes that the pygmy sperm whale, Kogia breviceps, is considered a species of Least Concern on the IUCN Red List of Threatened Species, with inadequate information on population distribution, size and trends. It is also listed in the Convention on International Trade in Endangered Species (CITES), but does not appear in the Convention of Migratory Species (CMS).

“This whale is circumglobal, therefore the stranding of it in Fiji should not be a surprise to us. It is simply the first time this species was reported to have stranded within Fiji. Within the paper other Pacific Island Countries (PICs) with stranding reports of this species and its sister species (kogia sima) are highlighted,” he said.

The paper records that the pygmy sperm whale was found lying on its right side less than 20 meters from shore, on a mudflat. The carcass was approximately 20 meters from the mouth of the stream where it was initially sighted. The paper further notes that an external examination of the cetacean, in particular, the shape of the head and position of the lower jaw suggested it to be a species of Kogia.

Dhem said: “The key aspect I wished to highlight by publicising this stranding event is in Fiji as with most other PICs there is no active or efficient network for reporting or recording cetacean strandings and sightings. As such, a lot of data is often lost, which can result in rare and endangered species from being excluded in national or regional management plans.”

The study noted that the first record of a pygmy sperm whale stranding was along the coast of Viti Levu, Fiji however, the inaccessible coastlines of the Pacific islands combined with the lack of an “openly accessible stranding records network and database,” makes it difficult to document these strandings. 

To emphasize this lack of an openly accessible record, the study points to another stranding of a rare whale that took place in the Mamanuca’s early last year. Researchers were also made aware of this event through Facebook pictures.

Dehm says: “That whale [in the Mamanucas], which many mistook for a dolphin, was likely a Longman’s beaked whale, which is the rarest of all whale species (only a handful of other specimens have ever been found/seen). If there had been a well established network for reporting whale strandings, this specimen could have made its way to museums and labs, or at the very least, morphometric measurements could have been taken.”

Dehm asserts that, when this data is lost, rare and endangered species are often excluded in national and regional management plans.

Social media played a critical role in the documenting of both of these strandings. Without locals posting their pictures both of these important events would have slipped from the records.

Photos by Brian Stockwell

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