Dolphins live in fission–fusion societies where individuals join and leave groups on a flexible basis. Several factors potentially affect the social structure and subgroups of these dolphins, including habitat structure (depth, distribution), predation risk, prey distribution, cultural transmission, and male competition.This report aimed to analyse the effects of environmental factors on the social structure of Stenella coeruleoalba in the Eastern Aegean Sea. Photo identification of an S. coeruleoalba subpopulation was used to record how often individuals were seen together, alongside their depth and distance from shore. This study concludes that depth and distance from shore did not differ significantly between subgroups. It has provided insight into how this sub-population appear to exhibit fission-fusion behaviour and can help inform effective management efforts. Analysing the social structure of S. coeruleoalba is important as complex social structure is a prominent feature in cetaceans for communication, reproduction, and protection, and can lead to behavioural diversity among and within a population.

Essex Student Journal Volume 16 Issue 1 2024