![]() ![]() We believe that this behavior is a response to risk of predation from large sharks. Utilizing drones in the field has increased our ability to stay with groups, as individuals tend to surface with different bearings compared to their overall direction of travel. Recently, we’ve been able to use drones to gather aerial footage of dwarf sperm whale behavior. ![]() While we have yet to be able to deploy a satellite tag or collet any biopsy samples of this species, we have built a long-term photo identification catalog consisting of 182 individuals, including several long-term resightings, and have collected a dozen aerial videos of behavior. Group sizes of dwarf sperm whales are typically small, ranging from 1 to 8 individuals (our most frequently encountered group size are single individuals).ĭwarf sperm whale off Kona. Both species also have a reputation for being difficult to approach, although we have found that, while they are difficult to keep track of, this is due to their long dive times, undemonstrative surfacing behavior (most of the time they float motionless at the surface between dives), and their generally unpredictable travel patterns, rather than active avoidance of small boats.Īn aerial photo of three dwarf sperm whales off Kona in 2019. The small, island-associated Hawai‘i population of dwarf sperm whales is the most well-described worldwide. Click on the image below to download a PDF copy of the information sheet with details on how to distinguish between the two species. It is often reported that the two species are difficult to tell apart in the field, but there are a number of characteristics that allow us to discriminate the two species. To learn more about dwarf and pygmy sperm whales, you can click on one of the quick links below: However, pygmy sperm whales strand much more frequently than dwarf sperm whales in Hawai‘i. In our work we’ve encountered dwarf sperm whales 97 times between 2002 and late-2021, while we’ve seen pygmy sperm whales on only eight occasions. ![]() While most knowledge of these species comes from stranded individuals, our work represents the most extensive study of this species in the world, and includes the only long-term photo-ID catalog of dwarf sperm whales. Both species are found in deep waters, and are infamous for being difficult to study both due to their preferred depths, long dives, low profile in the water, and frequent changes in direction. These two species are closely related, and in fact weren’t recognized as separate species until 1966. An adult dwarf sperm whale ( Kogia sima) off the island of Hawai‘i. Note the blunt head and large dorsal fin.ĭwarf sperm whales and pygmy sperm whales ( Kogia breviceps) are the only two members of the Family Kogiidae, and both species are found in Hawaiian waters. ![]()
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