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Where do seahorses live and what do they eat?
March 7, 2005
These unusual animals can be found
around the world. They live among coral reefs, mangroves
and beds of sea grass and sea weed in shallow, tropical
and temperate waters. In North Carolina, we have the lined
seahorse, Hippocampus erectus.
Seahorses belong to the Syngnathidae family of bony fish
and are poor swimmers. They don’t move around much.
Instead, they establish small territories and use their
grasping, prehensile tail to anchor themselves to objects.
Males will often spend several days on the same blade of
grass or piece of coral.
Seahorses feed on small
crustaceans, such as shrimp. Their small mouth
is at the end of their long tubular snout. They
don’t have teeth or a stomach, so they use
their snout like a vacuum to suck up tiny animals.
Without stomachs they can’t digest food efficiently
and must eat enormous amounts. A young seahorse
can consume up to 3,000 baby brine shrimp in 10
hours!
Seahorses can move their eyes independently, enabling
them to track prey with one eye and watch for predators
with the other. When threatened, they hold tightly
to a blade of grass or piece of coral and pull
their heads in close to their chests.
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During breeding season, seahorses form pair bonds and mate with only one other
individual. Several species perform elaborate courtship dances
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Another interesting thing about seahorses is that they
mate for life and the male carries and gives birth to the
young. The female produces eggs, but the male carries them
in his stomach pouch until they hatch. The father labors
a day or more before being able to force the live young
from the pouch. Depending on the type of seahorse, the
brood size ranges from 15 to 1,000 young. Newborns are
a quarter-to a-half-inch long and are exact replicas of
their parents. They are fully independent from birth. In
the wild, fewer than 5 of 1,000 young survive to adulthood.
Adult seahorses have few predators, however remains have
been found in crabs, tuna, skates and rays. Storms also
pose a threat to these small, weak swimmers. Heavy surf
can tear them from their holdfasts and cast them on shore,
or carry them out to sea where they are unable to swim
to safety.
Over the years, more than 100 species of seahorse have
been described, but currently only about 32 are recognized
be researchers. Unfortunately, seahorse populations are
declining. There appear to be several reasons for this:
Seahorses are heavily harvested for use in traditional
medicines, home aquaria and as curios and souvenirs. More
than 20 million seahorses are sold each year for traditional
Chinese medicine.
Humans also threaten seahorse survival by damaging habitats.
As people move to coastal areas in ever-greater numbers,
sediment from construction and agriculture, nutrients from
lawns and farms, and chemicals from a wide variety of sources
all end up in coastal waters. This can seriously disrupt
the natural processes of coastal habitats where seahorses
and other animals live.
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