LESSON 2 - SeaTrek Programs

Lesson 1
Discovering Dolphins
Bottlenose dolphins utilize various habitats. The size of the habitat influences group size. Offshore
groups tend to be larger than the more inland, coastal groups. Large group size helps to discourage
predators and allows for more opportunities to attract various mates. Although dolphins can be solitary, they
are generally found in social groups. These groups are typically females and calves (up to 5 years of age)
in nursery groups, which provides for additional maternal (allomaternal) care for the calves; juvenile males
and females (approximately 5-12 years of age); and bonded adult males who may partner for many
years. Bottlenose dolphins do not form monogamous male/female pairings. A female dolphin will generally
reproduce with several different males in her lifetime. Bottlenose dolphins often travel with the very young,
older, and/or weak animals in the middle of the group in order to protect these vulnerable individuals.
Living in groups provides additional benefits, such as opportunities for cooperative hunting. Dolphins are
known to work in groups cooperatively to surround prey and employ tactics, such as tail whacking and sonar,
to stun and confuse prey.
Figure 1.2: Tursiops truncatus world distribution (indicated in blue)
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