Scientist scours global waters in bid to save Earth's largest freshwater fishes

Scientist scours global waters in bid to save Earth's largest freshwater fishes

[ AP Photos NY372-374

Miranda Leitsinger
Associated Press/Phnom Penh

Floating down the Mekong in his dinghy, Zeb Hogan is on the
ultimate fisherman's quest: to find the world's largest
freshwater fishes.

The American biologist's search is to take him to 10 rivers
around the globe including the Nile, Amazon and Mississippi,
looking for about 20 species of hulking fish such as the goliath
catfish, Chinese paddlefish and North American lake sturgeon --
not to catch them, he says, but to save them.

"These big, amazing creatures all over the world, they might
be goners, on their way out," said Hogan.

Right now Hogan is on the Mekong that flows through the
Indochinese peninsula, looking for a stingray said to weigh over
1,300 pounds (600 kilograms) -- as much as a full-grown longhorn
steer.

He knows it's out there; he photographed one in 2002. And
smaller stingrays abound. As he passes villages on riverbanks or
floating on the water, he sees children playing with severed
stingray tails.

The 2,600-mile (4,183-kilometer) Mekong is known for its
diversity of river creatures, as well as their size, to judge
from places along its banks named the Pool of the Giant Catfish,
or the Pool of the Giant Carp.

Just last May, fishermen in Thailand landed a Mekong catfish
that weighed 646 pounds (293 kilograms) and measured 8 feet, 10
inches (2.7-meter) long. It's believed to be the largest
freshwater fish ever caught. It ended up on dinner tables.

"The main question I'll be asking everywhere is what were
populations like in the past, what are they now?" said Hogan.

"You'll see a pattern that these populations of these large
fish species are declining -- a lot."

These are not aquatic sasquatches he's looking for, but fish
whose existence is proven fact. The goliath catfish is still
fairly common, Hogan said, and Wisconsin has a fishing season for
lake sturgeon. The Chinese paddlefish is very rare, but a 275-
pound (124-kilogram) one was caught on the Yangtze River in China
on Dec. 11, 2003. There are said to be 650-pound (292.5-kilogram)
carp, but none over about 300 pounds (135 kilograms) has been
seen in recent times, Hogan said.

Almost all maximum lengths and weights come from accounts over
the ages by scientists, explorers and taxonomists, and "in many
cases have been verified by present-day scientists like myself.
That is, after all, one of the main objectives of the project,"
Hogan said.

Hogan, 31, a researcher from the University of Wisconsin in
Madison, has worked on the Mekong since 1996. His study is
supported by the World Wildlife Fund, the National Geographic
Society's Emerging Explorers Program, and outdoor-gear companies
Marmot and Patagonia.

He'll be working with other scientists studying the creatures,
such as a biologist researching the Amazon's arapaima, which can
weigh 450 pounds (202.5 kilograms), and a Texas freshwater guide
who will help him study the alligator gar, which can reach 300
pounds (135 kilograms).

As they putter down the Mekong, Hogan and his two Cambodian
assistants pass constant reminders of the importance of the
Mekong's fish population to the 73 million people living along
its banks. People busily mend nets, and at night, dozens of tiny
candles in floating containers mark where nets have been laid in
the water off Phnom Penh's riverfront.

Along the way, Hogan and his assistants pepper fishermen with
questions and pictures of their quarry.

The fishermen may not have caught or even seen the fish, Hogan
said, but often will say they have heard about it being somewhere
else. "Theoretically, that's supposed to lead us to where the
fish are."

Not always, though. He said fishermen are hesitant to admit
they've hooked a big one, for fear of running afoul of Cambodian
and international restrictions on hunting rare species. The
penalties are small, but the fishermen don't want the bother.

Hogan said he expects to finish in December 2006 and give his
fish counts to IUCN, the World Conservation Union, which compiles
a Red List of Threatened Species -- creatures threatened by
overfishing, pollution, dams and alien aquatic life introduced by
humans.

IUCN lists some of the giants as endangered or critically
endangered, but for others, there simply isn't enough data to
judge.

"We have a sense that the world's largest freshwater fish are
disappearing really fast," said Robin Abell, a WWF freshwater
conservation biologist. "We do need to work to understand both
the species and the threats to them."

"The most exciting part for me," said Hogan, "is that that no
one's done this before."

He believes the stingray ultimately will take the title, but
says he will adhere to tough standards.

"If I don't have a photo or a weight, to me, it's not
legitimate," he said. "I can't go just by word of mouth ...
fishermen are famous for exaggerating the size of fish that they
catch."

---
On the Net:
WWF: http://www.worldwildlife.org/science/projects/giantFish.cfm
National Geographic:
http://www.nationalgeographic.com/emerging/zebHogan.html
IGFA: http://www.igfa.org/
IUCN: http://www.iucn.org/

GetAP 1.00 -- AUG 31, 2005 07:25:03