With over 500 species of shark, ocean temperature preference varies with certain shark species.
Some species like cold water, while others like warm water. Some species have adapted to life in polar regions and the deep sea, where temperatures can reach anywhere between 0.7°C to 4°C – frighteningly cold. On the other side of the spectrum, some species can be found in tropical regions – understandably, as far away from the poles as possible.
Lastly, some species can tolerate the mixing of polar and tropical waters. These species are called temperate species and are typically large, migratory species. Within this category, many species deploy variations in survival mechanisms, such as remaining in an area with a constant temperature.
What water temperature do sharks prefer?
Most shark species are cold-blooded. Like reptiles, their body temperate matches the external water around them. Due to this, sharks must rely solely on the solar energy emitted from the sun.
Sharks are environmentally sensitive animals – they can detect even the slightest change in the external environment.
Water temperature plays an important part in shark migration.
Some species, such as the sandbar shark, will undertake seasonal migrations to follow oceanic temperatures.
Sandbar sharks migrate towards Northern New England in the summer months, when water temperatures reach approximately 16°C. Towards the start of Autumn, species will migrate back South towards the Gulf of Mexico and Caribbean, where waters can reach 25°C.
Many shark species have evolved to fill an ecological niche – a place in the ecological web that matches species to specific environmental conditions. Often, no two species share the same niche. This is perhaps why species of sharks have adapted to live in the polar regions.
What sharks like cold water?
Polar waters are oceanic regions where the water temperature rarely exceeds 3°C.
Although way too cold for you and me, there are some hardy species that have managed to make a living in these near-freezing waters.
Much like how terrestrial polar species, such as polar bears and penguins, have evolved to withstand low temperatures, so too have sharks. To the surprise of many, there are at least 8 species of shark that thrive in these cold waters.
The following list comprises some of the species of shark that like cold water:
- Spiny dogfish
- Pacific sleeper shark
- Salmon shark
- Greenland shark
Although uncommon, some shark species are endothermic – meaning they can raise their blood temperature to match water temperature. Species that have mastered this art can diversify into the frigid waters of the Arctic.
Due to the intense environmental pressures, these species have some unusual adaptations.
Consequently, they do not look like the “typical” shark. Some, such as the Pacific sleeper shark, have a heavily cylindrical body and a short, rounded snout.
Other species, such as the Greenland shark, can be found under the thick ice sheet of Arctic waters. Due to the cold water, metabolism and reproduction are slow. Consequently, some individuals have been recorded to reach over 400 years of age.
What sharks like warm water?
Tropical waters are nearest to the equator. Heated by the sun’s solar energy, the warm waters are distributed across the globe via oceanic currents. Water temperatures here are balmy, often 21°C or higher.
Many shark species like warm water. Species to be found in tropical waters are often large and predatory – where food is plentiful. They include:
- Tiger sharks
- Hammerhead sharks
- Bull sharks
- Reef sharks
Other species, such as the gargantuan whale shark, are also found in the tropics. The vast majority of their diet comprises plankton – phytoplankton and zooplankton – both of which rely on the sun’s solar energy to grow and thrive.
Often, species that live in this region are migratory. They roam the oceanic desert, following food availability and ambient oceanic temperatures. However, some species, such as the nurse shark, remain relatively sedentary, preferring to remain in localized areas of warm water.
Amazingly, nurse sharks can withstand temperatures above 30°C.
What sharks can be found in temperate zones?
The temperate zone encompasses much of the world’s oceans – all areas that are not around the equator and poles are classified as temperate waters.
Due to this large expanse of water, oceanic temperatures vary greatly. Typically, the water can range from as little as 10°C, all the way up to a comfortable 21°C.
Here, fluctuations in temperature are common, more so than any other ocean region, and many species have adapted accordingly.
A wide variety of shark species can be found here. Many are migratory, scouring great distances across the ocean to find food or mates. They include:
- Great white sharks
- Basking sharks
- Mako sharks
- Porbeagle sharks
Unlike other cold-bodied animals, these species can regulate their own body temperature. Because of this, it has enabled them to migrate further in search of food compared to their tropical counterparts.
Many temperate species can be found across the world, including tropical regions.
However, they will typically swim at a depth where the ocean temperate correlates to a water temperature they’re adapted to.
For example, great whites have been recorded to reach depths of 900 meters. At this depth, water temperature is approximately 13°C – a temperature the shark is more accustomed to.
How cold can sharks survive?
As previously discussed, sharks can tolerate a range of environmental conditions – from sunlit tropical waters to the icy depths of the Arctic.
Species that have adapted to live in Arctic conditions, where the ambient water can reach sub-zero temperatures, have a special protein found within their blood that can help them survive temperatures below freezing.
However, for species that have adapted to tropical regions, a serious problem threatens their survival: frostbite.
As crazy as it sounds, a shark can get frostbite. Just like humans can get frostbite in the tips of fingers and toes, sharks can develop frostbite in their fins if water temperatures drop drastically.
This is particularly problematic, as humans over-exploit the oceans and collapse fish stocks, causing sharks to migrate to deeper depths.
Sharks are thought to be one of the longest-lived vertebrate species swimming in our oceans – dating back millions of years.
Part of their success comes from their widespread distribution. They are found in all of the world’s oceans, owing to their incredible adaptability to fill certain niches.
There are some species that can withstand the freezing temperatures of the Arctic, while others can endure temperatures above 30 C.
However, many of the shark species we are familiar with live in the tropical and temperate waters – often around the equator and beyond – with temperatures remaining a pleasant average of around 21°C.