Theme 3 - Sharks are generally long-lived, late maturing,
have low fecundity and often have small population sizes.
Consequently, such species are particularly susceptible to
overfishing and are slow to recover if overfished.
Most sharks have a low reproductive potential attributed to their slow growth and delayed
maturation, long reproductive cycles and low fecundity (a small number of offspring). These aspects of
their biology also mean that shark populations are slow to recover if they are overfished.
Some of the commercially important shark species give birth to their young in shallow coastal
waters. The young remain in these areas (nurseries) for months or years. These sharks are very
vulnerable to modern fishing operations. Sharks are also caught in high-seas longline fisheries. Even
so, some valuable and biologically sustainable fisheries for sharks do exist. Such fisheries are closely
monitored by scientists.
Importantly, the Australian Government has recently implemented its Sharkplan
as its response to the International Plan of Action for the Conservation and Management of
Sharks. This should help to ensure the long-term sustainable use of Australia’s shark populations.
Ideas for schools
Find out about what species of sharks are sold in your local fish shop.
Investigate how these sharks are caught and what is done by fisheries management agencies to protect
species from overfishing. Also, see the relevant information sheets on the MESA Seaweek 2005 web site compiled by
Terrence Walker, Julian Pepperell and Kevin McLoughlin, with links to the schools-activities booklet.
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