We have some great news about our sperm whale research, published online this week in Marine Mammal Science.
Futurismo’s biologist Miranda van der Linde, lead author on the research has been studying the sperm whales encountered during our whale watching tours for the past 9 years. This is the first published research on sperm whale occurrence and social structure off São Miguel Island in the Azores.
This new research showed that just like in other well studied populations of sperm whales, the females and young we encounter live in units that stay together for many years. Some whales and units seemed to prefer associating with each other, indicating long term bonds between relatives or friendships between certain individuals.
The research also showed that the majority of sperm whales we encounter can be recognised by distinct pigmentation marks on their bodies, not just by their tails. The encounter data and photographs collected by Futurismo’s marine biologists are an important contributor to science and help increase our understanding of the whales and dolphins we encounter in the Azores.
The sperm whales we encounter here live in “units” of about 6 whales on average, but we have also identified larger units of up to 13 individuals. Two or more units can also come together to create large groupings, and this is something we often see during our whale watching tours.
We have already encountered groupings of up to 50 sperm whales in an area. During our encounters we often cannot photograph the tails of all sperm whales present, which is how we typically recognise individuals (from the natural marks on their tails). However, our research shows that most of our sperm whales (about 78% of them) can also be recognised by distinctive pigmentation marks on different parts of their body.
The image below shows sperm whales we have identified off São Miguel island since 2010, and how they are connected to each other.
Different colours represent the social units identified in the study. Circles represent females and young sperm whales and black triangles represent mature males.
The connections show that female and young sperm whales mostly associate with individuals from their own social unit.
Some pairs of social units seem to prefer associating together, for example we often encountered individuals from the “red unit” and the “purple unit” together.