Anglerfish: Nature’s Fishing Masters

Yellow Magpie — Wed, 16 Dec 2009 09:00:50 +0000

The deep-sea anglerfish inhabits would of the darkest, most oppressive and dangerous environments on Earth. In a place where most submarines would be crushed due to the pressure, these fish thrive.

One of nature’s strangest animals, this highly adaptive fish has one of the most unusual of appearances. Long before people ever held a fishing rod this fish had mastered the act of fishing.

There are many fish and amphibians which fall under the moniker ‘anglerfish’. In fact, there are in excess of 300 hundred species.

The Fishermen Of The Ocean

They are called after their method of catching fish. They use a growth on their head as a lure to attract fish. This lure is known as the esca and is flexible to allow the fish to move it in any direction. Bacteria in the esca illuminates for other fish and potential meals to see. This relationship is also beneficial to the bacteria as the anglerfish provide them with a constant source of food.

The esca acts as a bait and brings prey right into the anglerfish’s jaws. The anglerfish is armed with a fiercesome array of sharp, backward-pointing teeth. They can swallow prey twice their body size due to a distending jaw and expanding stomach. Only the female possesses a lure.

Strange Macabre Reproduction

Deep-sea anglerfish reproduction is amazing. As males reach sexual maturity, their digestive system becomes redundant. When this happens they must quickly find a female or risk death. The male fish has an acute sense of smell. He uses this heightened sense to locate the female.

Once the female is located the male proceeds to attach himself to her body by biting into her skin. The male is then assimilated into the female and all that remain are a pair of testes. The female now can fertilise her eggs as soon as she is ready to spawn.

Deep-sea anglerfish also hold one unmatched record. The Photocarynus spiniceps is the smallest known vertebrate at 5mm (quarter inch) in length. Of course it is the male of the species that holds this record, the female can sometimes be hundreds of thousands of times bigger.

Vital Statistics

Anglerfish can be up to one metre (three feet) in length.
They can weigh 50 kg (110 lbs).
Some anglerfish can live as long as 30 years.
They are found throughout the world.

http://www.youtube.com/watch?v=UXl8F-eIoiM

Catfish: The Animal With The Best Sense

Yellow Magpie — Wed, 28 Oct 2009 09:00:20 +0000

A large blackness silhouettes itself against the flowing waters of a quick moving river. This large-bodied creature meanders along the bottom. In a clear stretch of the river it reveals itself. Enormous appendages frame its face, marking it apart from nearly every other fish.

Catfish are a strange animal. One of the most prized catches amongst fishermen, their unusual appearance is also a subject of fascination for many people. Upon viewing a catfish it is plain to see why they are given their name. Their large barbels look remarkably like feline whiskers.

From the frozen wilderness of the Himalayas to the warm waters of the Pacific, from fresh water to salt water lakes, catfish are amongst the most adaptable animals on the planet.

A Varied Diet

The majority of catfish are bottom feeders. Because of this, they sink to the bottom of water and are said to be negatively buoyant.

Their source of food depends on the species. Some catfish are parasitic while others eat rotting corpses that lie on the sea or river bottom. Other, larger catfish will eat almost anything from frogs to snakes.

The Most Sensitive Fish

An incredibly varied and adaptive species, the catfish accounts for one-twelfth of all the fish on Earth. But this is only half the story.

What truly makes catfish such a remarkable family of fish is the sensitivity of their senses. They have the best sense of taste of any back-boned creature. This is achieved manly by having more taste buds than any other vertebrate.

Every single available space on their bodies is allotted for taste-sensing purposes. Even their whisker-like barbels are covered in taste buds. Furthermore, the smaller catfish species have hundreds of thousands of taste buds on their bodies.

Catfish are not just possessors of great taste-sensing abilities, their sense of smell together with their hearing and touch is also second to none. They are able to smell compounds as weak as one part in a billion.

Sensitive To Sound

Catfish’s bodies have the same density as the surrounding water and this acts in a peculiar and remarkable way. Their whole body become an ear drum allowing them to detect the faintest noises. Even extremely low frequency sound can be detected using tiny hair-like projections inside the fish’s pores. Many Japanese people maintain that catfish can detect earthquakes days in advance so sensitive is their hearing.

Sensitive To Touch

Unusually, catfish do not have scales. This proves to be highly advantageous and some species can breathe through their skin. Their lack of scales also results in the fish having a greater sensitivity to touch.

Catfish eyesight is also acute and they can spot other fish from quite a distance in clear water. To add to their already heavy arsenal of sensors, catfish, much like sharks, can detect electrical fields in a sense known as electroreception. They use this to devastating effect when they search for their prey in mud.

Sought-After Delicacy

Catfish remain a valuable source of food throughout the world and in many countries they are a delicacy. No matter what country you live in you can rest assure that there is some restaurant that will serve catfish on their menu.

Dangers Of Catfish

Some catfish pose a threat to human health. The most infamous catfish is the Candiru. There have been widespread reports of this fish travelling up people’s urethras and lodging itself there after erecting its spines. Often surgery is the only option to remove the parasite.

However, it is thought that this only happens when the victim is urinating in water.

Vital Statistics

Catfish can be as small as one centimetre (half an inch) or as large as 5 metres (16 feet) in length.
They can weigh as little as a couple of grams or as much as 300 kgs (650 lbs) for the European wels.
Catfish are found everywhere but Antarctica.

http://www.youtube.com/watch?v=nTuoUDprKiU

Yellow Magpie » Fish

Anglerfish: Nature’s Fishing Masters

The Fishermen Of The Ocean

Strange Macabre Reproduction

Vital Statistics

Further Reading

Catfish: The Animal With The Best Sense

A Varied Diet

The Most Sensitive Fish

Sensitive To Sound

Sensitive To Touch

Sought-After Delicacy

Dangers Of Catfish

Vital Statistics

Further Reading