Sawfish at Risk

You wouldn't think a fish like this would be in trouble.

The smalltooth sawfish grows up to 20 feet in length and 1,300 pounds in weight and brandishes a long, chainsaw-like bill lined with two rows of razor-sharp teeth. Etchings from the 19th century even depict the massive creatures viciously sawing through the side planks of fishing vessels.

But the real demeanor of the fish, which belongs to the same family as sharks, is reportedly laid-back and sluggish — hardly threatening.

And despite its heavy equipment, scientists estimate populations of the smalltooth sawfish have declined by nearly 99 percent in the past five decades. The National Marine Fisheries Service concluded last week that the fish, which once ranged from the Gulf of Mexico all the way to the waters of New Jersey, is "in danger of extinction."

Great Weapon, Bad Handicap

If the agency grants the sawfish endangered species status, it would be the first marine fish living in U.S. waters to be listed.

Sonya Fordham of the Center for Marine Conservation, the Washington, D.C. advocacy organization that filed a petition to grant the animal status, argues the decision to grant the sawfish endangered status is not just about this peculiar fish. She says it carries implications for all marine species.

"If we're abusing our oceans to the point where we're driving a species extinct, it's probably an indicator of a larger threat to the ocean," she says.

In the past, fish populations have generally proved to be robust since they reproduce in great numbers and live in the vast habitat of oceans. But fishing and coastal development have affected marine environments in recent years. And, the smalltooth is no ordinary fish.

In fact, the very appendage that makes the fish fierce also puts it at risk.

"That neat bill that's studded with teeth is very easy to get caught up in any kind of net," explains John Musick, a biologist at the Virginia Institute of Marine Science in Gloucester Point, Va.

While fishing for the smalltooth sawfish is not legal, the fish is easily snared by gillnetting and trawling intended for other fish species and shrimp. Even if a fisherman releases the fish, the animal is often fatally injured during the awkward entangling process.

Sawfish also live in more unstable regions of the ocean. Populations spend much of their time nestled in the muddy floor of shallow ocean waters. Because they're near shore, they become more vulnerable to human disruptions such as dredging, sea walls and oceanside development.

Scientists believe the long-snouted fish's slow reproduction rate is another factor behind its decline. The smalltooth sawfish reaches sexual maturity only after about 10 years (that's 10 times the life span of many fish) and then reproduces only about once every two years.

"Most fish species are prolific and are less vulnerable to overfishing," says Fordham. "These fish grow slowly and mature late so they can't quickly replenish their numbers."

Female sawfish give birth to 10-15 live young and special features protect the mother from possible sharp encounters. Inside the uterus, the snouts of the sawfish are folded back against their bodies and their teeth are encased in "sheaths" of cartilage before birth. After emerging from the womb, the bills of the sawfish unfold and lose their coverings.

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