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Are sharks social?
As a rule, sharks, skates, rays, and chimaeras tend to be solitary animals.
When they come together outside of the breeding season (on reproduction,
see chapter 6), it’s most likely a result of the mutual attraction of individuals
to food. So, for example, White Sharks will gather to feed on dead whales;
Gray Reef and Silky sharks will home in on injured fish; and Basking and
Whale sharks and Manta Rays will converge on dense patches of zooplank-
ton. Sometimes, as happens in the Maldives during the southwest mon-
soonal season, hundreds of Reef Manta Rays and dozens of Whale Sharks
aggregate at the same areas to feed on the same dense swarms of krill (small
crustaceans). Although uncommon, some aggregations of sharks can result
in a classic feeding frenzy. Feeding frenzies are antisocial gatherings, given
that everything in the area can be bitten, including other sharks.
However, some species form small, apparently social groups, often
when they are not feeding. Species that rest by day and feed by night may
aggregate during their daytime resting period and then disperse to feed at
night. Adult Small-spotted Catsharks gather in all-female groups in shal-
low, inshore caves during the day, in large part to avoid being harassed by
male sharks. Small groups of Port Jackson Sharks (Heterodontus portusjack-
soni) rest in caves during the daytime, disperse to feed at night, and then
return to the same cave the next morning. Nurse Sharks spend the day
in inactive groups of up to 40 individuals, also dispersing at night to feed
and returning each morning to the same resting site. Some Whitetip Reef
Sharks follow a similar pattern of daytime, grouped resting in caves andChapter 4
Shark Behavior
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