With the frigidity of winter air descending on land, the same cold pervades the ocean, affecting the fish that live in it. Sea creatures fall into a category called Poikilotherms, meaning that they are cold-blooded animals, and therefore require lots of heat that they cannot generate themselves. So as cold as you are in these last few months of the year, the fish in the sea are just as, if not more, cold than you.
Eels in particular are drastically affected by this temperature shift, as they require not only warm body temperatures but warm waters in addition. To solve this problem they do what you may be familiar with birds doing… migrate. Eels are capable of living in many different environments; particularly saline waters, seeing as they can live in fresh, brackish, and saltwater environments.
A common misconception about eels is that they are a separate species, when in fact they are merely other derivatives of a larger class of rayfin fish and ridgeback fish respectively. Additionally, they can be found all over the world, provided the temperatures are right. So not only do humans take vacations to warmer climes in winter, nor just birds, even fish do it!
