Nano Gobies

Aquarists armed with nets go hunting for the exotic
coral fishes that suddenly appear by the thousands
off the coast of Long Island in the summer months.
The Gulf Stream flows northward along the Atlantic
coast of North America. It is part of a larger current system,
called the North Atlantic Gyre, that encircles the
entire North Atlantic Ocean. Although the Gulf Stream
is a surface current, it runs deep enough that it is bound
by the continental shelf. This explains why tropical
reef communities can be found in the inshore waters
of south Florida, well outside of the tropics, where the
continental shelf is very close to the shore. It also allows
tropical communities to flourish offshore on a narrow
band of the continental shelf as far north as Cape
Hatteras, North Carolina. The shape of Cape Hatteras
and its submarine extension, the continental shelf—
along with some help from the Coriolis effect—acts to
deflect the rapidly flowing Gulf Stream to the east of its
northward course. This puts the tropical, clear blue current
several hundred miles east of the coastline by the
time it reaches the latitude of Long Island. At its closest
approach to Long Island, the Gulf Stream averages approximately
200 miles away (to the southeast). North of
Cape Hatteras, the Gulf Stream is free of any continental
boundaries and its course becomes more erratic, shifting
and oscillating as a result of wind and the opposing
Labrador Current.
The Gulf Stream is just one of many factors contributing
to the climate and the species composition of
marine communities in New York and the rest of the
northeastern United States. Sport fishermen in search
of migratory species like tuna, mahi-mahi, and billfish
track eddies that spin off the main current and bring
The warm waters of the Gulf Stream, indicated in red, flow
northward, carrying tropical species to the cold North Atlantic.
pockets of tropical water closer to shore. Some of the
best fishing takes place at the boundary between the
warm tropical water of the Gulf Stream and the cool,
nutrient-rich water of the Labrador Current.
The ubiquitous Bluefish, Pomatomus saltatrix, uses
the Gulf Stream to disperse its larvae along the U.S.
coastline. The larvae develop as they ride the Gulf
Stream; then, taking cues from wave patterns, they head
for the coast when they reach a critical point in their
development. Like most marine fish species, the Bluefish
has a small pelagic larval stage. This reproductive strategy
is about producing an enormous number of offspring,
but putting very little energy into each one (the opposite
of our human reproductive strategy). It’s a common
CORAL
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