mad-as-a-marine-biologist

griseus:

A redeye gaper (Chaunax sp.) venting water at 240 meters depth. Seen during the Lophelia II 2008 expedition at the Green Canyon site in the Gulf of Mexico.

Gapers are Lophiiformes, in the anglerfish group, with big heads, a network of open sensory canals,and a lateral canal extending posteriorly along a compressed trunk and tail. They are sit-and-wait, ambush predators

First Live Observations of a Rarely Seen Deep Sea Anglerfish

by Dana Lacono (August, 2012)

With a bulbous body and spiky scales, a shaggy lure dangling from its head, and foot-like fins that it uses to “walk” along the seafloor, the deep-sea anglerfish Chaunacops coloratus looks like something out of a Dr. Seuss book.

In a recent paper, MBARI researcher Lonny Lundsten and his coauthors describe the first observations of these rare fish in their natural, deep-sea habitat. In addition to documenting these fish walking on the seafloor and fishing with their built-in lures, the researchers discovered that the fish change color from blue to red as they get older.

C. coloratus was first described from a single specimen collected off the coast of Panama during an expedition in 1891 aboard the U.S. Fish Commission steamer Albatross. However, for over 100 years, marine researchers collected deep-sea fish using trawl nets and dredges, so this anglerfish was never seen alive. That changed in 2002, when researchers from MBARI, Moss Landing Marine Laboratories, and the Monterey Bay National Marine Sanctuary used the remotely operated vehicle (ROV) Tiburon to explore Davidson Seamount—an extinct volcano off the coast of Central California…

(read more: Monterey Bay Aquarium Research Institute)

Nautilus Live:
Check out this Angler fish we found in the deeps of the Gulf of Mexico - it uses the long lure on its head to entice prey. They are opportunistic feeders, and this deep sea dweller is often found facing the seafloor waiting for prey. Fun Fact: Angler fish are fantastic energy savers - by staying as still as possible while hunting and foraging, they can use a mere 2% of their total available energy for swimming.

Check out this Angler fish we found in the deeps of the Gulf of Mexico - it uses the long lure on its head to entice prey. They are opportunistic feeders, and this deep sea dweller is often found facing the seafloor waiting for prey.

Fun Fact: Angler fish are fantastic energy savers - by staying as still as possible while hunting and foraging, they can use a mere 2% of their total available energy for swimming.

ichthyologist
ichthyologist:

Sexual Parasitism in Deep Sea Anglerfish
In response to the perilous and opportunistic conditions of the deep sea, some deep sea anglerfish have evolved a very specialised method of reproduction - sexual parasitism.
Due to the fact that individuals of a species are locally rare, encounters between a male a female are very uncommon. As such, when they eventually meet, the fish employ a unique mating method that will ensure that they never separate again.
The fish display extreme sexual dimorphism, with males being many times smaller than females. The method by which a male finds a female differs across different species, but can involve sight or pheromone cues.
When a male anglerfish encounters a female, he latches onto her body with his mouth. He then releases enzymes that digests the skin of his mouth and her body, which fuses the pair down to the blood vessel level…
(read more)
Image: © Pietsch, TW

ichthyologist:

Sexual Parasitism in Deep Sea Anglerfish

In response to the perilous and opportunistic conditions of the deep sea, some deep sea anglerfish have evolved a very specialised method of reproduction - sexual parasitism.

Due to the fact that individuals of a species are locally rare, encounters between a male a female are very uncommon. As such, when they eventually meet, the fish employ a unique mating method that will ensure that they never separate again.

The fish display extreme sexual dimorphism, with males being many times smaller than females. The method by which a male finds a female differs across different species, but can involve sight or pheromone cues.

When a male anglerfish encounters a female, he latches onto her body with his mouth. He then releases enzymes that digests the skin of his mouth and her body, which fuses the pair down to the blood vessel level…

(read more)

Image: © Pietsch, TW

Eerie Critters from the Deep:  Spooky Eyes

Just in time for Halloween, a collection of deep sea creatures with enormous eyes from the Monterey Bay Aquarium Research Institute…

Glass Squid, Owl fish, Vampire Squid, Rattail fish, Longnose Skate, Crystal Isopod, Spot Prawn, Barreleye fish, Slickhead fish, Sea Toad fish, Dover Sole, Swordtail Squid, Shiny Loosejaw fish, 8-armed Squid, and Ray Troll’s Ratfish.

(via: MBARI)

ichthyologist
ichthyologist:

Anglerfish
Like all anglerfishes, frogfish use a lure to attract prey, akin to a fisherman and his bait. Its front most dorsal fin, called the illicium, is topped with a lure, known as the esca.
While the rest of the fish is camouflaged, the frogfish waves and vibrates the illicium, causing the esca to resemble prey. Curious fish approach the lure, thinking that it is food. When it is close enough, the frogfish quickly expands its mouth and sucks in the prey, in as little as 6 milliseconds.
© Randall, J.E. via eol

ichthyologist:

Anglerfish

Like all anglerfishes, frogfish use a lure to attract prey, akin to a fisherman and his bait. Its front most dorsal fin, called the illicium, is topped with a lure, known as the esca.

While the rest of the fish is camouflaged, the frogfish waves and vibrates the illicium, causing the esca to resemble prey. Curious fish approach the lure, thinking that it is food. When it is close enough, the frogfish quickly expands its mouth and sucks in the prey, in as little as 6 milliseconds.

© Randall, J.E. via eol

The psychedelic frogfish, Histiophryne psychedelica, is named for its psychedelic pink and white stripes arranged in a fingerprint pattern. This species was described in 2009 from three specimens collected off Ambon and Bali, Indonesia.  The psychedelic frogfish moves by walking on its pectoral fins over the seafloor. It can also bounce like a rubber ball, jet-propelling itself by forcing water out of its gill openings.  More about this fish on EOL: http://eol.org/pages/10215240/details (Image by David Hall)

The psychedelic frogfish, Histiophryne psychedelica, is named for its psychedelic pink and white stripes arranged in a fingerprint pattern. This species was described in 2009 from three specimens collected off Ambon and Bali, Indonesia.

The psychedelic frogfish moves by walking on its pectoral fins over the seafloor. It can also bounce like a rubber ball, jet-propelling itself by forcing water out of its gill openings.

More about this fish on EOL: http://eol.org/pages/
10215240/details

(Image by David Hall)

The Future of Deep Sea Exploration
Twenty-four astronauts have been on or near the Moon; 12 of them landed on the Moon and actually walked on its surface. By comparison, three people have been to the deepest part of the ocean: Jacques Piccard and Don Walsh in 1960 and James Cameron in 2012. Isn’t it time to do some more ocean exploring?  This July, follow along as 100 of the top ocean explorers gather at Ocean Exploration 2020: A National Forum to shape our nation’s ocean exploration program and a develop strategy for getting there. You will have the opportunity to provide input in defining the future of ocean exploration: 
http://oceanexplorer.noaa.gov/oceanexploration2020/welcome.html (About the image: An angler fish lies in wait on young lava flows from Volcano W, an active submarine volcano in the Kermadec Arc, located north of New Zealand. This species was previously unknown to inhabit in New Zealand waters prior to being spotted during an expedition in 2005)

The Future of Deep Sea Exploration

Twenty-four astronauts have been on or near the Moon; 12 of them landed on the Moon and actually walked on its surface. By comparison, three people have been to the deepest part of the ocean: Jacques Piccard and Don Walsh in 1960 and James Cameron in 2012. Isn’t it time to do some more ocean exploring?

This July, follow along as 100 of the top ocean explorers gather at Ocean Exploration 2020: A National Forum to shape our nation’s ocean exploration program and a develop strategy for getting there. You will have the opportunity to provide input in defining the future of ocean exploration:

http://oceanexplorer.noaa.gov/oceanexploration2020/welcome.html

(About the image: An angler fish lies in wait on young lava flows from Volcano W, an active submarine volcano in the Kermadec Arc, located north of New Zealand. This species was previously unknown to inhabit in New Zealand waters prior to being spotted during an expedition in 2005)

The Monkfish (Lophius piscatorius)

This anglerfish lies half-buried in the mud or sand on the bottom of the sea, attracting fish to its huge mouth by means of its lure. Fish are drawn in by the sudden inrush of water. This method of feeding is a speciality of the various groups of anglerfish worldwide.  

Anglerfish spawn between May and June in British waters, and between June and August in the North Atlantic. The eggs, numbering up to a million, are contained in a band of mucus about 10 metres long, released to drift in the open ocean. The larvae, when they hatch, look just as extraordinary as the adult fish. They mature at a length of 40 cm and at an age of four years for males, and a length of 70 cm and an age of six years for females. A fully-grown adult anglerfish may live for 20 years or more.

(read more: Encyclopedia of Life)

(photos: T - Nordsømuseet Hirtshals; ML/B - SERPENT Project; MR - National Museums Northern Ireland)