Today during the afternoon excursions with our zodiac “Stenella” we encountered pods of Bottlenose dolphins (Tursiops truncatus) and Short-finned pilot whales (Globicephala macrorhynchus) in close proximity to each other. The groups of both species were mixed in ages with a remarkably high number of very young animals, especially among the Pilot whales.
During this time of the year we observe lots of juvenile cetaceans of various species although they have different gestation periods. Generally, the calf’s relationship with its mother is crucial for its survival.
Dolphin mothers teach their offspring how to hunt. They chase their prey longer and show more referential body-orienting movements during foraging when their young ones are present than without them. Having their kids around they also travel with a reduced speed of only 76% of the mean maximum swim speed.
Scientific studies indicate that the pods undertake specific movements to avoid predation risks when there are newborn animals with them. Alloparental care is common among various dolphin species but also reported from big whales, like e.g. Sperm whales (Physeter macrocephalus).
We don´t know whether the close proximity of the Bottlenose dolphins to the Pilot whales we observed today plays a role regarding the protection of the young animals. Maybe one day we´ll be able to tell.
by Jan-Christopher Fischer
Sightings of the day
Stenella
09:00 Blainville´s beaked-whales, Loggerhead turtle
12:00 Bottlenose dolphins, Short-finned pilot whales
15:30 Bottlenose dolphins, Short-finned pilot whales
Ribeira Brava
09:00 Blainville´s beaked-whales
17:00 Bottlenose dolphins, Short-finned pilot whales