Angler fish have the bright antenna, so look out for that whe. Trying to locate one.

There tend to be quite a lot of angler spawns in North zone near Carno Island

The dilophosaurus of the seas...

Anglers are found in the deeper parts of the ocean, finding them is as one would guess easy as their lures are easy to see at a distance, they are comparatively easy to kill for gel ( taming food for Mantas and the best fuel in game ) but in groups exceeding three then I suggest running, best take a megaladon.
Also can be lured by other tamed anglers lures.

The terror birds of the sea the are extremely annoying just like the terror birds on land

Valguero: Found in the aberration area in a shallow stream of all the places. Has a contingent of spino and karkino troops. Expect heavy casualties.

There's nothing quite like having one of these sneak up behind you while illuminating the toothy grin of a plesi.

Beware: Can be in schools of over 100 in some trenches.

I saw them in the southern cave be' carefull cuz if u fall in the water you will be stuck there unless you have a belzebufo

Lives deep in the ocean waters, at the darker zone where the Dunk lives.

From a distance they have a similar appearance as silica pearls. Tread carefully everywhere you go

if you see a pack of electric eels... its already too late

More common the further north you go, so not suggested to such for on south coast.

These thing are found in the deep ocean

Since they tend to retreat and charge after taking some damage,having a fast water mount (or at least flippers) is good to get off and back on when trying to ko or kill. I prefer the Sarco for its AoE bite against multiple and infinite stamina in water (however it only has one speed in water anyways, but it's still fairly quick depending on level). If escape is necessary bite it with the Sarco when it gets too close and swim away when the angler retreats. Crossbows (and most, if not every, other weapon) do work on its back, if you'd rather not get off.

Anglerfish will damage wood. With that said, build a cage on your plesiosaur platform and trap it like a quetz. So much easier.

Pro tip: This guy is not very nice, according to the encounter Nemo had with it, it did not end very well. If you encounter one just swim away and observe from a safe distance. When killed they drop angler gel which have their certain uses, its best to fight these with at least a Megalodon.

These little slips will kill you when you.are getting good deep sea drops

One word: Run. If you don't listen,u will die

If you just don’t want to die then I’d suggest getting your health, weight and oxygen maxed out before you go into the water, this also goes for all other dangerous sea monsters.