Transcript:

Today on Animal Fact Files we’ll be discussing anglerfish. For more facts on awesome animals be sure to subscribe to the channel! Anglerfish were suggested by YouTube user Abysmii who also created the music accompanying this episode. He has developed some amazing stuff on his channel and we highly recommend checking him out!

When you hear the name anglerfish what immediately comes to mind? For most the image that appears may look something like this. However, this, this, and this would also be accurate. This is because fish commonly known as anglerfish belong to the order Lophiiformes which is split up into five different suborders containing more than 300 individual species. These five suborders contain the fish typically referred to as monkfish, frogfish, sea toads, bat fish and sea devils. Technically speaking, any fish from any of these suborders could be referred to as an “anglerfish” so for the sake of clarity, today we’ll focusing on sea devils. Any instance of the word “anglerfish” in this episode from this point forward will be in regard to sea devils or deep sea anglerfish. Whew. You guys know how much I love animal kingdom nomenclature. Anyway, on to those freaky fishes.

Sea devils are deep-sea dwelling fish who typically live somewhere between half a mile (800 meters) and one and a half miles (2,500 meters) below the ocean’s surface - though some live more than two miles (3,200 meters) down. Since they live in an area that’s so difficult for us to explore, we have limited information on them, but some of the facts that we do know are pretty impressive. There are more than 150 species of deep-sea anglerfish and probably more to be discovered. Many species possess a bioluminescent organ that developed on the first spine of their dorsal fin as a lure for drawing in prey. This is called an esca. The light of this lure is created via a symbiotic relationship between photobacterium and female anglerfish. Yes, only female deep-sea anglerfish have this lure, the males? Well… we’ll get to them in a minute. It’s also been documented that some species of deep-sea anglerfish are able to produce their own bioluminescence making them the only group of animals discovered so far according to the American Museum of Natural history to use glowing bacteria and produce their own light. By this logic, we can surmise that the anglerfish seen in Finding Nemo is likely a female Leftvent anglerfish since she lights up even more upon discovering Marlin and Dory… BUT THAT’S JUST A THEORY. In a study of monkfish it was discovered that they seem to favor dining on crustaceans and other fish. Perhaps deep sea anglers seek out similar meals, as well. Sea devils may also consume squids as suggested Nat Geo WILD’s YouTube video titled Weird Killer of the Deep. Whatever they eat, it’s likely it’s the females doing most of the munching.

What male sea devils lack in the esca department they make up for in the size of their nose. It’s assumed this adaptation has occurred due to the single life purpose of the male deep-sea anglerfish: to find a mate. The deep parts of the ocean are a dark and mysterious place, the kind of place that will make you want to hold tight to your significant other and never, ever let go. When a male sea devil meets up with a female, he will latch on to her with a big bite at her belly and over time become fused to her body becoming solely dependent on her. It’s not uncommon for a female deep-sea anglerfish to have five or more males attached to her at any given time. And all of this to ensure the survival of their species. With the males taking codependency to a whole new level, this gives females open access to sperm at any time she is ready to produce offspring.

Deep-sea anglerfish are typically less than a foot in length (30.5 cm) with males appearing smaller than females. They are usually dark brown or grey in color and can often appear black as well. One of their defining characteristics is that they lack pelvic fins after very early life stages. They’re considered to be the most species rich group of animals found in the deep ocean and more species are being found at a steady rate. As recently as 2015 a new species was found in the Gulf of Mexico. Hmm… maybe I’m dating the episode in saying that…

For more facts on deep sea anglerfish, please read through the links in the description. Thanks again to Abysmii for the suggestion and this awesome soundtrack - let him know what you think of it in the comments! Be sure give a thumbs up for weird creatures of the deep and we’ll see you next time on Animal Fact Files!