Finding the best habitats for humpbacks
Kyoto UniversityPeer-Reviewed Publication
Kyoto, Japan -- Humpback whales are one of the most popular species for whale watching. Since they are active close to the water's surface, groups of whale watchers can often see them breaching and diving during breeding periods. One popular whale watching destination is the Ogasawara Islands -- also known as the Bonin Islands -- a remote archipelago about 1,000 kilometers south of Tokyo. These isles serve as a key breeding ground for humpback whales, which migrate in large numbers every December to May to these coastal waters.
Scientists have identified one of the main habitats of humpback whales in the Ogasawaras to be the Chichijima Island group, also home to the archipelago's main human settlement. Yet exactly which areas around Chichijima are critical for these whales has remained a mystery. This motivated a team of researchers at Kyoto University, the Ogasawara Whale Watching Association, and Tokyo University of Marine Science and Technology to model the whales' distribution using sighting survey data.
The team examined visual survey data collected from vessels used by the Ogasawara Whale Watching Association in 2013 and also from 2015 to 2018. This data includes the locations of 160 groups of whales, totaling 234 individuals, that were confirmed during the five-year survey. The team then used two species distribution models to combine this data with topographic factors such as water depth, seabed slope, and distance from the coastline in order to predict the most suitable habitats for humpback whales.
- Journal
- Mammal Study