Don't free Nemo: Exotic fish plaguing reefs
BY NADA JONES
Special to The Citizen
KEY LARGO — Flushing your
pet tropical fish or releasing it at the beach are bad ideas.
Not only is doing so
punishable with a $1,000 fine, but increased sightings of nonnative
exotic fish from the Red Sea and the tropical western Pacific on local
Keys reefs signal increased potential for disease and overrunning of
native species, say scientists in a University of Washington report.
In addition to the
report's findings, volunteer divers and snorkelers working through the
Key Largo-based Exotic Species Sighting Program of the Reef
Environmental Education Foundation (REEF) have photographed and
videotaped 16 nonnative species of fish in the Florida Keys.
The documentation started
in the mid 1990's, when a volunteer diver who was counting fish for REEF
noticed that the native Atlantic Spadefish he was looking at had a
distinctive yellow marking on its tail fin and was really an invader.
When the discovery of the
Pacific-based orbicular batfish was phoned in to REEF's exotic species
sightings hotline, the organization announced the finding to local dive
operators and tourist agencies. It was not long before the invaders were
found and trapped on Molasses Reef and taken to the Florida Aquarium in
Tampa for educational display.
Now, 15 years later,
these fish are joined by a newly acquired pair of the same species that
was caught on the same reef in June 2004.
"Exotic fish collecting
seems to be a big hobby in Florida, and I think most folks don't do
their homework and release invasives when they get too big or too
expensive to take care of," said Casey Coy of the Florida Aquarium.
REEF Director Laddie
Akins says he wishes all exotic fish stories had such happy endings. He
attributes the successful removal of these exotics from the Florida Keys
National Marine Sanctuary to a swift response to the problem, despite
there being only two or four of them sighted.
"They were smart in being
proactive on this and not waiting until it turned into a huge problem,"
he said, referring to the alarmingly large number of red lionfish seen
from New York to Bermuda to Florida. Lionfish are native to the Red Sea,
as well as the Indian and Pacific oceans. This situation has alarmed not
only Akins, but also scientists from other organizations.
In Florida, six lionfish
were accidentally released in Biscayne Bay from a home aquarium during
Hurricane Andrew in 1992. Divers also reported lionfish off Palm Beach
and Boca Raton in the early 1990's.
The exotic-looking
lionfish is the first nonnative ocean fish to successfully invade North
America's Atlantic coast — from North Carolina on up the eastern
seaboard — in documented maritime history. Their abundance and size
indicates they have settled in and begun to breed successfully.
They devour smaller reef
fish whole, depriving the larger Atlantic fish of a vital food source.
Thus far, no other fish has been found to eat the lionfish, which bear
long, poisonous spines protruding at all angles from their bodies.
Humans are warned to be wary of them for the same reason they are being
left alone by their would-be predators.
NOAA and the National
Undersea Research Center (NURC) at the University of North Carolina at
Wilmington have been counting and tracking them. Over the course of two
weeks, the NURC team counted 75, some a foot long and weighing up to 2
pounds a piece.
Where do they all come
from?
According to the FWC,
there are 32 freshwater exotic fish known to be reproducing in Florida
waters.
Collectively, these fish
represent one of the most diverse, abundant and well-studied exotic fish
faunas in the world. The FWC adds that all but one of these exotic
fishes were illegally released by individuals, through draining of
aquaculture systems or flooding of ponds.
Although it's not
cut-and-dried, it is a fine line between unwelcome invaders and welcome
ones. The FWC says that many nonindigenous species provide economic,
recreational and social benefits. For example, an important sport
fishery was established using the nonindigenous butterfly peacock bass.
Florida's thriving
aquarium industry has cultured a wide variety of valuable and benign
species since the 1920s. Nowadays, it is no surprise to see that even
the benign species have found their way into the wild and become
established among the native population.
According to scientists,
the aquarium and wildlife trade is where most of the marine invaders
come from. There is another theory about international tankers and
exotic fish in ballast tanks, but that has proven inconclusive. The
ballast tanks have not produced the same kinds of fish that are found to
be the invaders, REEF Science Coordinator Christy Pattengill-Semmens and
Brice Semmens, a UW doctoral student in biology, say.
The UW co-authored report
that was published in the Marine Ecology Progress Series Journal in
January 2004 says that an unprecedented number of nonnative marine fish
exists in a concentrated geographic area: 16 species were found in 32
different locales along the coast of Broward and Palm Beach counties and
in the Upper Florida Keys.
Some were in the Florida
Keys National Marine Sanctuary, including the orbicular batfish.
The other introduced
species that the Pattengill-Semmens report outlines are native to the
tropical western Pacific and/or Red Sea. Emperor angelfish, with their
blue masks and bodies striped in blue and gold, were the most commonly
sighted nonnative species and are imported by the aquarium industry in
relatively large numbers. Another commonly sighted nonnative was yellow
tang, a bright yellow oval fish that is the most commonly imported
species of the U.S. aquarium trade.
Under Florida law, it is
a crime to purposefully release any nonnative species into the wild. FWC
regulations also state it is illegal to "negligently" allow the escape
of captive wildlife or nonnative fish. The FWC language on this
encourages exotic pet owners to ensure their charges are securely caged
at all times.
They suggest violations
should be reported through the FWC's toll-free wildlife alert numbers
listed in local telephone books and warn that continued escape or
establishment of exotics in Florida could result in additional
restrictions on the importation, sale and possession of nonnative
wildlife.
"I think we are going to
see tougher regulations in the pet trade. The biologists are studying
the issue further and looking at prohibiting more of the fish they
notice as being capable of doing harm or are most commonly released,"
FWC Lt. Paul Reynolds said.
Although the obvious step
is toward a joint effort between the aquarium industry and natural
resource agencies such as the FWC to develop a program to educate
dealers and aquarists about the legality and environmental impacts of
exotic species introductions, little progress has been made to date in
combating what the FWC calls "biological pollution."
Public education is
especially critical in areas such as the southeastern United States,
which has a regional climate and habitat suitable for the tropical
marine fish species common in the aquarium trade and is, therefore, at
relatively high risk of successful invasions.
What you can do
The FWC suggests anyone
needing to dispose of exotic fish should give them to a friend or
aquarium store or euthanize them in a bag of cold water, possibly adding
ice or placing in a freezer.
"So, bringing the pet
shops on board is a primary step in the process. It's not a law. It's
nothing but good-natured cooperation. They are being asked to do the
right thing. We've come out with a mailing to ask for them to take these
animals back, but most of them are not all that concerned about the
environment," Reynolds said.
According to Keys
Kritters owner Robert Majeska, returning fish purchased at his store is
not a problem. Store employee David Martinez also likes to keep himself
up to date about the issue and shows customers the "exotic species
warning" poster in the store.
One problem he faces is
how to handle a situation in which a customer returns a fish that is
aggressive toward other fish, he says. Saltwater fish, he adds, are very
territorial.
They take the selling of
a Nemo-type fish — a colorful, exotic saltwater variety — very seriously
and will give potential customers a thorough questioning before they
sell anything like the famous clown fish idol.
"We have had something
like five or six people a day coming in asking for the Nemo fish since
the movie came out. They have to go in a 6- to 8-gallon tank or bigger,"
Majeska said. "If they come in asking for a Nemo fish in a bowl, we tell
them 'no.'" |
