Two weeks ago, we looked at the five fastest fish in the sea. This time, we look to the other end of the speed spectrum. So here are five slow pokes of the marine world:
Greenland Shark – 75cm/s
Also known as the world’s slowest swimming shark, the elusive Greenland Shark (Somniosus microcephalus) can grow up to 7.3m long, making them one of the largest fish, and the biggest in the Arctic. Yet despite being almost as massive as Great White Sharks, their top speed is a lethargic 75cm/s.
One likely reason for its (lack of) speed is the energy cost of regulating its body temperature in the almost freezing depths.
Here’s another interesting fact: many Greenland Sharks are blind due to the parasite Ommatokoita elongate which permanently attaches itself to the front of the sharks’ eyes, damaging their corneas. Watch this video to learn more about Greenland Sharks:
Sea Star 0.3cm/s
There are about 2,000 species of sea stars living in the world’s oceans. While the five-arm varieties are the most common (hence their name), species with up to 40 arms exist.
Sea stars are also known for their ability to regenerate limbs. They are able to do so because most or all of their vital organs are located in their arms. Read more interesting facts about sea stars here
Seahorse – 0.04cm/s
Seahorses propel themselves by fluttering the small fin on their back, while the smaller pectoral fins near the back of their head are used for steering. They are often seen swimming in pairs with their tails linked together, keeping them in line with each other. According to the Guinness Book of World Records, Dwarf Seahorses (Hippocampus zosterae) are the slowest fish in the ocean with a top speed of about 0.04cm/s.
Check out this article to learn more about Seahorses and how our vets at S.E.A. Aquarium take care of them.
Sea Slug – 0.01cm/s
The bizarre yet beautiful Sea Slugs can be found in oceans all over the world. Varying widely in color and shape, they may look like typical slugs, bottle brushes or even Christmas ornaments.
Sea Slugs have poor vision. Their sense of the world is obtained through their rhinophores (on top of the head) and oral tentacles. They are also hermaphrodites, meaning each Sea Slug has both male and female reproductive organs.
Recently, researchers at Case Western Reserve University created a biohybrid robot made from the muscle of a sea slug. And here’s a video of what is possibly the world’s most adorable sea slug – the Sea Bunny:
Corals – largely immobile
They may look like rocks or plants but corals are animals related to sea-anemones and sea jellies. During their larval phase, corals move about as free-living creatures. Once they mature, they settle down at a fixed spot and remain largely immobile. Despite their “immobility”, most corals have tentacles that extend out of their shell to grab passing bits of food, mainly microscopic plankton.
Here’s a brilliant video by photographer Daniel Stoupin who documented the “slow” marine life, such as corals and sponges, in the Great Barrier Reef. This three and a half minutes of timelapse took nine months to create and is simply breathtaking.