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SPRING 2016
DIVE SLATE
LIONFISH
W
hy in the world would
someone catch an invasive
lionfish only to let it go again?
First documented along
the east coast of Florida in
1985, most likely as a result
of aquarium releases, Indo-Pacific lionfish have quickly
spread throughout the Western Atlantic, Caribbean and
Gulf of Mexico. The invasion is likely to continue well
into South America through Brazil. Much is now known
about the invasive fish, including their distribution,
reproduction, predation impacts and genetics, which
have all been subject to rigorous scientific study.
Divers and the dive industry have been very
effective at controlling lionfish populations in some
locations through regular, ongoing removals, but
eradication is not possible at this time. One-day
fishing events, such as lionfish derbies, have been
shown to remove large percentages of lionfish across
a wide range, but recolonization can occur within
months. Lionfish removals have been incentivized
by the establishment of lionfish as a highly regarded
food fish, but removal efforts to date have amounted
to “weeding the garden,” with no long-term solution
in sight. Much work is now focused on researching
more effective control tools and techniques, including
lionfish-specific traps, attractants and other high-
tech approaches such as deep-sea rovers, undersea
vacuums and more. More information about lionfish
is still needed, however, to better inform control
efforts and design new removal tools, which leads us
to letting lionfish go.
Essential information about any invasive species
includes when, why and how much they move. When an
area is culled, lionfish recolonize it through both juvenile
recruitment and adult fish moving into the territory.
Knowing how much lionfish move is one of the keys to
designing effective diver removal programs, and one of
the best ways to determine movement is through a mark-
and-recapture study. But marking lionfish can be tricky.
Handling a venomous fish is always a challenge,
but poking, prodding and piercing one with a tag can
LIONFISH
MANAGING THE INVASION
By Lad Akins
A new method of tagging lionfish at depth
eliminates problems associated with barotrauma,
anesthesia and displacement, improving the
data researchers collect about site fidelity,
movement patterns and growth.
COURTESY STUART COVE’S