Creature Feature: The Lancet Fish and Polar Bears

February, 2017

The Lancetfish, Alepisaurus ferox

Although the spiny-tailed, two-fanged, longnose lancetfish, or Alepisaurus ferox, looks like a strange deep-sea creature, these fish inhabit deep waters worldwide (down to 6,000 feet). The lancetfish is a species rarely seen on coasts and is usually found in polar bodies of water as by-catch for tuna. In addition to their nocturnal lifestyle and unique characteristics, the lancetfish is a mysterious yet defying species to both biologists and the public.

The specific name is derived from ferox, meaning feral or ferocious. Lancetfish have a large mouth with large fangs indicating it is predatory, but its watery muscles suggest it might not be suitable for a fast or long-term hunt. Past stomach content studies have found squid, shellfish, and fish. Other instances revealed evidence that its own species had been consumed, which predicated them to sometimes be called cannibal fish.

Lancetfish are the largest species in the family Alepisauridae, growing up to four feet long on average, with the largest recorded at seven feet. They are also considered one of the largest fish in the deep sea. They have a distinct, sail-like dorsal fin that gives it the nickname “handsaw fish.” The swim bladder is absent though scientists do not know why.

Furthering the mystery of these fish is their reproductive system. Adolescent longnose lancetfish are hermaphrodites, meaning they possess both testes and ovaries, but they also have external sperm ducts and there are distinct, external openings for both sperm and oviducts. Fertilization takes place externally, though it is unknown if self-fertilization occurs or if it is even possible. It is also unknown if this hermaphroditic state happens in adult lancetfish. Lancetfish are not endangered. Those who have eaten lancetfish meat claim it is more gelatinous than other fish but remains tasty.

In May 2014 a live lancetfish washed ashore in North Carolina, where media headlines read “Scary fanged cannibal fish washes ashore alive” and “Terrifying, fanged cannibal fish discovered on American beach.” Beach-goers were warned to watch out for their toes due to a vampire-esque creature lurking in the water.

Locally, one turned up on a Crescent City beach on January 16, 2017. Humboldt resident Rob Fowler captured the photo to the left, and unsuccessfully tried to pull it back into the surf. When he returned hours later, the mysterious fish was gone.



Polar Bears: Doomed to Extinction Due to Climate Change?

It’s official: The polar bear population will likely go extinct unless we take drastic and long-term actions against climate change.

In January, the U.S. Fish and Wildlife Service (FWS) released their Conservation Management Plan for the polar bear, singling out climate change-driven sea ice loss as the “primary threat” to the survival of the species. The plan calls for a number of solutions to save the species including reducing human-bear conflicts, protecting denning habitat, and minimizing the risk of contamination from oil spills. “Short of action that effectively addresses the primary cause of diminishing sea ice, it is unlikely that polar bears will be recovered,” the plan states. In 2008, the polar bear was the first species to be added to the Endangered Species Act due to climate change. The current global polar bear population is estimated to be 26,000.

The area of the Arctic covered by sea ice in October and November 2016 was the lowest on record for those months since recordkeeping began in 1979, according to FWS.

“The plan said the outlook is grim for bears only if international governments do absolutely nothing to address climate change,” David Douglas, a U.S. Geological Survey researcher, said in a recent interview with the Washington Post. “But if they limit some greenhouse gases, even if Trump withdraws the United States from the Paris climate agreement, polar bears will have a slightly better chance of survival.”



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