Monster Catfish Found In Virginia

The recent capture of what could be North America+IBk-s largest recorded
blue catfish+IBM-in Virgina in late June+IBM-has us thinking about this
oversized species and its relatives.

The Virginia blue caught last month weighed in at 143 pounds and
measured 57 inches. (The previous record was a 130-pound catfish
caught in Missouri last year.)


A drawing of a blue catfish (Ictalurus furcatus), courtesy of Duane
Raver/U.S. Fish and Wildlife Service.



(See more pictures of some of the planet+IBk-s biggest fish.)

We asked fish expert and National Geographic Fellow Zeb Hogan+IBQ-also an
assistant research professor at the University of Nevada+IBQ-to put this
giant discovery into perspective:

Can you tell us more about this species +IBQ- its range, habitat
requirements, status, and any threats it may face?


Blue catfish is native to 20 states, primarily within the Mississippi
River Basin but also in rivers along the Gulf Coast. It has been
introduced in another nine states, including Virginia. It is a big
river species; it grows quickly, and it+IBk-s popular among anglers for
aggressive behavior and good quality meat. It is the largest catfish
in North America and the third largest obligate freshwater fish in
North America, behind the lake sturgeon and paddlefish.


+IBw-Mark Twain mentions large catfish in his books+IBQ-those fish were likely
blues.+IB0-

Blue catfish are the focus of many urban legends, mostly stories of
huge catfish below dams. While stories of catfish the size of cars are
most likely exaggerations, there are confirmed reports of blue catfish
weighing over 200 pounds from the 1800s, and the largest unconfirmed
catch, landed in 1866 in Portland, Missouri, weighed in at a whopping
315 pounds. If these reports are true, it gives some perspective on
the recent catches and a glimpse into the true potential of the blue
catfish if left to grow undisturbed in a healthy environment. Many
states, including Virginia, consider blue catfish as an important
sportfish and people travel long distances for a chance to catch a
trophy fish. Blue catfish populations are considered relatively
healthy at the center of its range. On the periphery of its range,
populations have declined, primarily due to habitat modification, dam
construction, river flow modification, wetland drainage, and
pollution.

Do people eat blue catfish?

People definitely eat blues, and have been eating them for a long
time. Mark Twain mentions large catfish in his books+IBQ-those fish were
likely blues. Blue catfish were also relatively common in the St.
Louis fish market in the 1800s. They have a reputation for firm,
tasty meat and lots of it. In some areas catfish harvest is now
restricted+IBQ-either to a set limit per day, a certain size of fish, or
in rare cases catch-and-release only. Usually, these rules are in
place where fisheries officials hope to develop a trophy fishery (i.e.
a recreational fishery for very large fish).

Catfish as a group are an extremely important food fish+IBQ-in the U.S.
alone we consume hundreds of millions of pounds of catfish each year.
In Asia, where catfish is an even more important resource, almost one
and a half million tons of fish are produced annually. Catfish are
also an important food fish in Africa and South America, where they
make up most of the catch in many areas.


+IBw-Incredibly, there are also stories of places where catfish have
attacked and even eaten people.+IB0-

Incredibly, there are also stories of places where catfish have
attacked and even eaten people. Large catfish in North America and
Europe have reportedly bitten humans, and one species of very large
catfish in Northern India is rumored to stalk and occasionally kill
local villagers. These stories are often sensationalized and
exaggerated however and there is very little hard evidence of catfish
behaving aggressively toward people. To learn more about these
stories, and the truth behind them, watch the story of India+IBk-s giant
catfish on National Geographic Channel.

When were blues introduced to Virginia?

Blue catfish were introduced into Virginia in 1974. Since they can
live over 20 years and are capable of growing very quickly, the
extremely large fish coming out of Virginia now may have been among
the first fish to be introduced there over 30 years ago. It would be
interesting to know the age of 143 lb record breaker and since the
fish did not survive, I suspect someone is gathering that information
now (the easiest way to age a fish is with its ear bone, sacrifice of
the fish is required).

How does the blue compare to other catfish? What makes it special or
especially interesting?


The blue catfish is North America+IBk-s largest catfish species and it is
one of the largest freshwater fish in the U.S. If we look outside the
U.S., however, there are several larger species of catfish. In fact,
globally, catfish are some of the largest and most widespread of any
species. There are several that reportedly grow up to 600 pounds and
almost 10 feet long. The Mekong giant catfish is the current record
holder based on the catch of a 646-pound specimen in 2005.

(Watch a video on the Mekong catfish and learn more about this massive
species.)

The recent catch of several record-breaking fish is interesting
because it implies that blue catfish may be living longer+IBQ-and growing
larger+IBQ-than at any time in the last few decades. This may be
partially due to management of blue catfish fisheries for trophy-size
fish, but it is probably also because blue catfish have been
introduced into areas outside their natural range where there is an
abundance of food. Introduced species can often undergo a population
boom just after introduction. The same phenomenon occurred when wels
catfish was introduced into the Ebro River in Spain.

(See the trailer for the National Geographic Channel+IBk-s Monster Fish
episode on the wels catfish, starring Zeb.)

Is fishing for these giant catfish legal?


Recreational fishing for blue catfish is legal in most states+IBQ-and in
fact, blue catfish were introduced outside of their native range to
increase angling opportunities for sportfishing. The release of
non-native fish is controversial, because big predators like blue
catfish almost certainly alter food webs and species diversity in
areas where they are introduced. Commercial fishing for blue
catfish+IBQ-and other large species of North American catfish+IBQ-has been
scaled back in recent years due to the perception that large-bodied
catfish cannot support intensive harvest. In other parts of the
world, catfish support huge fisheries+IBQ-both wild capture fisheries and
aquaculture. Catfish are some of the most popularly cultured fish in
the world with millions of tons of fish produced each year. Catfish
fishing is only illegal in a small number of places where it has been
determined that fishing is unsustainable.


+IBw-While a lot of people think of catfish as ugly, they are actually one
of the most diverse and important groups of fish on the planet.+IB0-

Why should we care about catfish?

While a lot of people think of catfish as ugly, they are actually one
of the most diverse and important groups of fish on the planet. And
not all catfish are created equal: we tend to think of catfish as
slimy bottomfeeders, but that is only true for a small percentage of
species. Catfish come in a variety of sizes (some grow to almost 10
feet in length, while others are among the smallest fish on Earth) and
they display an impressive array of behaviors and life histories (some
make the longest migrations of any freshwater fish, while other live
their entire lives in small ponds and creeks).

Throughout their range, catfish are an important component of
commercial, subsistence, and recreational fisheries. They can also
have an important role in the ecosystem as top predators or as
indicators of overfishing. Multiple and combined threats from
habitat degradation, dams, water withdrawals, pollution, and
overexploitation have led to the decline of many catfish populations.

(Read more about dams and megafish on the NatGeo NewsWatch blog:
+IBw-Dog-eating catfish, other river giants threatened by Mekong dam
plan.+IB0-)

Despite these challenges, self-sustaining populations of large-bodied
catfish still exist. Globally, efforts to protect the ecological
integrity of rivers where large-bodied catfish occur will benefit
thousands of species of freshwater fish and millions of people who
rely on fish for their livelihoods and food security. Plus, they+IBk-re
cute!

For more on Monster Fish, visit the National Geographic Channel
website.

And read more about the monster blue in the Washington Post.

http://newswatch.nationalgeographic....ogan-explains/