It’s that time of year again where the winds get a little chillier and the skies a little darker. We humans can wrap ourselves up in scarves and matching hats, but what about our underwater wonders of the oceans? They can’t be seen swimming through the Atlantic in a cosy onesie, so, how do sea creatures cope with the colder temperatures of winter?
Baby, it’s cold outside
To our disappointment, aquatic creatures don’t cosy up together with a brew and a blanket – although, that would be cute, right? They actually migrate to the bottom of the waters where the warmer temperatures are. The density of warm water is higher than cold water, which is why warm water falls to the bottom, and that is where you’ll find sea creatures as they try to stay cosy this winter.
In extreme freezing temperatures in places such as the Antarctic, it’s often hard for creatures to find warmer waters. These creatures have become accustomed to these temperatures and, as such, they have developed ways to stop them catching a severe case of fish flu.
Deep-sea creatures tend to move very slowly because the cold temperatures slows down their metabolism. Thanks to special enzymes and high unsaturated fats in their cells, they are able to deal with the cold temperatures.
Creatures such as sharks that have been around for millions of years have learned to adapt to different surroundings, and because of this they are not fazed by the chill. Sharks living in the icy waters are known as endotherms with biological abilities of raising their blood temperature to complement their surroundings. Do you reckon you could adapt to shark waters? Let’s find out – we promise the water won’t be too cold.
I can see clearly now
It’s not just us who have to come to terms with the clocks going back; our sea creatures do too. Natural light can only reach to the shallow depths of our oceans, and once 200m-1km deep, the water becomes what is known as the twilight zone. No, you won’t bump into Robert Pattinson, but you might bump into a vampire squid or two.
Because the depths of the oceans are so dark, these fascinating creatures use electro senses and vibrations to sense their prey or predators. The underwater wonders don’t stop there. Creatures such as jellyfish can produce their own light and illuminate the waters in front of them so they can see.
Endotherms vs Ectotherms
Endotherms: warm-blooded creatures that create heat from within their bodies.
Ectotherms: creatures that have to gain heat from outside, because they cannot generate heat energy internally.
How do endotherms cope with extreme temperatures?
Endothermic creatures are usually large with a well-insulated body mass, thanks to stored fat immediately beneath their skin, and external insulation such as fur and feathers. To help generate further warmth, their diet contains an abundance of high-energy, easy-to-digest foods to constantly keep their body temperatures high.
We all like to cosy up in the winter under a blanket, and these creatures do the same too – just without the blanket. Known as huddling, creatures such as penguins group together to retain warmth and protect themselves from harsh winds. Penguins cuddling – cute, right?
How do ectotherms cope with extreme temperatures?
For ectothermic creatures to survive the cold winters, they have developed specific strategies over time to ensure they can keep warm. Using the technique of basking, creatures such as turtles lie in the heat to increase their body temperatures. When their body temperatures become cooler, they move around less and slower to help conserve their heat and energy.
The strategy of burrowing is used to protect creatures from cold air and use layers of the earth or water as a blanket from the harsh environment. So, technically creatures do use blankets in the winter – now, that’s what we call cosy.
If winter is getting a bit much for you too, why not come and meet some of these wondrous creatures in person? We can’t guarantee they’ll be dressed in matching hats and scarves, but they’ll definitely fascinate you with their underwater antics. Don’t forget to tweet us @SEALIFECentre or tag us on Instagram, so we can see your winter stories.