Most species prefer to remain close to the coast where they are commonly found in large schools near the continental slopes. Different species have been known to separate themselves according to depth. They will form dense layers according to species. It is believed that this behavior helps to reduce competition between species. These layers contain so many fish and are so dense that they can actually be visible on sonar.
They can reflect the sonar beams and give the impression of a false ocean bottom known as a deep-scattering layer.
This phenomenon confused oceanographers for many years until the source was finally identified. To search this site, type your search word s in the box below and click the search button:. All rights reserved. Content from this Website may not be used in any form without written permission from the site owner. Sea and Sky receives commissions for purchases made through links on this site. Having just returned from a recent DEEPEND research cruise, Freed is currently parsing through mountains of samples and microbial DNA sequence data that could provide greater context to anglerfish life history and help us better understand what is at risk when perturbations strike in deeper parts of the ocean.
Using specialized equipment, the team extracted seawater samples at 4 to 5 different depths maximum m at 12 different locations in the northern Gulf of Mexico with the hope of locating the luminescent bacteria within the approximate home range of anglerfishes.
A female anglerfish larva from the Linophrynidae family collected in the northern region of the Gulf of Mexico. They also collected 24 anglerfish samples at various life stages. Keep in mind these fishes are still pretty rare and difficult to find. We actually caught an anglerfish species of which there were only 12 currently known specimens worldwide! Living at depths between , ft , m , these species undergo nightly migrations to the surface to feed, descending once again to the depths during the day.
One explanation for this behavior is that vast quantities of tiny plankton rise to the surface of the ocean at night; species that feed on this rich food source, such as the lantern fish, therefore gain from having a condensed source of food at such times. Lantern fish also take advantage of the fact that they are not alone in harvesting the plankton; other small species such as amphipods and krill are also consumed at such times.
By retreating to the gloomy depths during the day, they may also reduce the risk of predation from larger species. The lantern fish is able to control the intensity and frequency of its flashing lights, and it is likely that the intermittent flashing serves a dual purpose.
With glowing blue-green lights embedded all over its body, the aptly-named lanternfish is well equipped for seeing and signaling in the dark. Special light-producing organs called photophores line its belly, helping the fish blend in with light-speckled water and confuse predators that might attack from below. This superpower is fairly common for deep-sea creatures, but lanternfish have the distinction of an extra row of photophores running down their sides.
For the most diverse family of fish in the deep ocean, the ability to signal to others of their species is kind of like having a custom dating app to find their mates.
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