Deep-Sea Mysteries: 5 Anglerfish Facts You Haven't Heard

Anglerfishes are some of the most mysterious and interesting creatures in the deep. Their beautiful bioluminescent lures and strange mating habits, however, are only the tip of the iceberg. There are many equally fascinating lesser-known aspects of their biology and behavior. Here are five interesting anglerfish facts.
The female anglerfish is endowed with the long rod-shaped projection from her forehead which extends into an end tip luminous esca; this is called the illicium. This long rod functions as a fishing rod with its luminous tip glowing bright in the dark waters of the ocean to lure unsuspecting prey close enough so that the anglerfish can catch it.
The males are much smaller than the females in many families of anglerfish. The main behavior of the male is to search for a female and attach himself to her. Over time, he fuses with her body, sharing her bloodstream and providing sperm for reproduction. The rare encounter becomes a guarantee that the female will always have a mate in the vast deep sea.
Anglerfish eat prey that is twice the size of their bodies. Because the mouths and stomachs can expand, they can swallow the big prey whole. This is the most crucial in the deep sea since food is rare, and they can take every bite that drifts along.
With a total of at least 200 species, anglerfish are some of the largest fish families. They are found at varying depths and in diverse environments in the ocean. Although most of them live in the deep sea, there are some that occupy the shallow waters. This all shows that they can survive in different kinds of marine habitats.
The anglerfish usually spends its life deep in dark waters of the ocean, although it has been seen on few occasions near the ocean surface. Such events occur, like in February 2025, when a black seadevil anglerfish was observed swimming near the surface of the ocean off the coast of Tenerife in the Canary Islands. These are very rare occurrences that might offer scientists some insights into these secretive animals before they rush back into their normal habitats.
Anglerfish are mysterious deep-sea creatures with fascinating adaptations, from their glowing lure to their unique way of mating. Though rarely seen, they play an important role in the ocean’s ecosystem. Their strange yet amazing features remind us of how diverse and incredible marine life can be.