S. attenuata S. frontalis S. longirostris S. clymene S. coeruleoalba S. rayi Stenella is a genus of marine mammals in Delphinidae, the family informally known as the oceanic dolphins.

[2][3] Individuals of several species begin their lives spotless and become steadily more covered in darker spots as they get older.

[6] Stenella dolphins tend to be more active during nighttime and spend their daytime resting.

Although these dolphins are supposed to spend 60% of their daytime resting, they happen to be exposed to human activities for 80% of their day.

These patterns of sleep deprivation can have negative impact on their resting habit and leads to decline in their population size.