A family of dolphins swimming of Wasini Island off the coast of Kenya, Africa.

Dolphins are often regarded as one of Earth's most intelligent animals, though it is hard to say just how intelligent. Comparing species' relative intelligence is complicated by differences in sensory apparatus, response modes, and nature of cognition. Furthermore, the difficulty and expense of experimental work with large aquatic animals has so far prevented some tests and limited sample size and rigor in others. Compared to many other species, however, dolphin behavior has been studied extensively, both in captivity and in the wild.

Dolphins are social, living in pods of up to a dozen individuals. In places with a high abundance of food, pods can merge temporarily, forming a superpod; such groupings may exceed 1,000 dolphins. Individual dolphins communicate using a variety of clicks, whistle-like sounds and other vocalizations. Membership in pods is not rigid; interchange is common. Dolphins can, however, establish strong social bonds; they will stay with injured or ill individuals, even helping them to breathe by bringing them to the surface if needed. This altruism does not appear to be limited to their own species. The dolphin Moko in New Zealand has been observed guiding a female Pygmy Sperm Whale together with her calf out of shallow water where they had stranded several times. They have also been seen protecting swimmers from sharks by swimming circles around the swimmers or charging the sharks to make them go away.

Dolphins also display culture, something long believed to be unique to humans (and possibly other primate species). In May 2005, a discovery in Australia found Indo-Pacific bottlenose dolphins (Tursiops aduncus) teaching their young to use tools. They cover their snouts with sponges to protect them while foraging. This knowledge is mostly transferred by mothers to daughters, unlike simian primates, where knowledge is generally passed on to both sexes. Using sponges as mouth protection is a learned behavior. Another learned behavior was discovered among river dolphins in Brazil, where some male dolphins use weeds and sticks as part of a sexual display.
Dolphins engage in acts of aggression towards each other. The older a male dolphin is, the more likely his body is to be covered with bite scars. Male dolphins engage in acts of aggression apparently for the same reasons as humans: disputes between companions and competition for females. Acts of aggression can become so intense that targeted dolphins sometimes go into exile after losing a fight.

Male bottlenose dolphins have been known to engage in infanticide. Dolphins have also been known to kill porpoises for reasons which are not fully understood, as porpoises generally do not share the same diet as dolphins and are therefore not competitors for food supplies.

Wasini Island lies off the southern Indian Ocean coast of Kenya next to Shimoni. It is approximately 5 km long and 1 km across. The island is sparsely populated and undeveloped. There are no cars or roads. A site of early Swahili civilization, this coral island is occupied by the Vumba people, an indigenous group of Bantu speaking peoples who have a rich history. They speak Swahili and Kivumba and they number about 1500. Mkwiro and Wasini are the two villages present on the island - each at opposite ends. Their history includes invasion and settlement of Arab influence from the Persian Gulf states, and from the island of Zanzibar, further south.

Located in south west Kenya, this population has the highest infant mortality rate in the country. Poverty levels are indicative of poor historical and current development.

Paradoxically, the island is some 10 km from the Kisite-Mpunguti Marine National Park. This park annually attracts many thousands of overseas and local tourists per year. The Kenya Wildlife Service monitors activities and there is a per visitor entry fee. These fees are not recirculated currently within the auspices of the collection area - instead they are remitted to Headquarters in Nairobi. The majority of visitors arrive on prepaid packages organised outside of the Island and outside of Shimoni. The larger operators are foreign owned. Many such organisations claim to operate responsible tourism - eco tourism. The tourist numbers generated in the area over the years are not monitored for environmental or socio economic impact.

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