Page 133 - The Miracle of Migration in Animals

Foraging Migrations

Marine fish migrate in many dif-
ferent ways. One or more migrations
are in progress at all times, be it a ques-
tion of a few meters or hundreds of me-
ters over either hours or days. The only
common factor in these different jour-
neys is the motive, since a great num-
ber of fish migrate regularly to feed.
Coastal fish migrating to feed

make use of the tides, by means of
which they reach the shore and are
then carried back to their territory.
Each day, they spend a few hours for-
aging over the submerged tidal flats.
Some fish regularly migrate for forag-
ing on a day-night cycle. The grunt, so
named because of the sound it makes
when it is caught, is a colorful school-
ing fish on Caribbean coral reefs. To
avoid being eaten, these fish shelter in
the crevices of the reef during the day

and at dusk, venture out in schools to
where food is plentiful. In the seagrass
meadows, they scatter and feed on the
invertebrates they find. Just before
dawn, they follow the same route back
to the reef. Each school uses the same
path day in, day out, for many years. 38

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