A long-beaked dolphin known for spinning as it leaps out of the water.
It has a slender body and thin flippers that curve backward.
Spinner dolphins around Hawaiʻi Island follow a daily pattern: they forage offshore at night and return to sheltered bays to rest during daylight. Tyne et al. combined boat- and land-based group observations, then used three models with data from inside and outside bays to examine resting habitat. Rest was unlikely outside sheltered bays. Within bays, resting occurred across daylight hours and peaked from 10 a.m. to 2 p.m.; seafloor substrate also helped predict where rest was observed.
A bay thus functions as habitat that supports a daily behavior, rather than serving as scenery alone. The authors recommended keeping resting areas free from human activity during key rest periods. These results come from coastal Hawaiʻi Island; other island populations need their own observations.
IUCN Red List · Least Concern (LC) · Global species-level assessment
The global IUCN assessment lists the Spinner Dolphin as Least Concern (LC), assessed on 20 February 2018, with population trend Unknown. The assessment cites its wide tropical distribution and no evidence that threats are significant across the full range. The 2018 global assessment notes that the eastern spinner dolphin subspecies, Stenella longirostris orientalis, was listed as Vulnerable (VU) in a separate 2012 assessment. The species and subspecies entries cover different taxonomic scopes.