Alert Diver Category: Life Aquatic

Do you know which marine animal can camouflage the fastest and most effectively? (It can change in one fifth of a second!) Hint: It has eight long tentacles.

It is early June, the onset of winter in the Southern Hemisphere, and an army has just reached its destination. It has marched from the ocean’s depths into the shallows, amassing among the pilings at Blairgowrie Pier in Port Phillip Bay, south of Melbourne, Australia. 

When you think of a billfish, what comes to mind? Perhaps it’s a swordfish, a sailfish, or even the giant marlin from Ernest Hemingway’s classic The Old Man and the Sea. It can be confusing because 12 species are collectively known as billfish: one swordfish, four spearfish, two sailfish, and five marlins.

Her legs move quickly as she scrambles over the sand toward a large coral reef. It’s a bold and risky move, as the expanses of sand between coral patches are full of predators waiting to take advantage of a lone spiny lobster. 

In November 2021 I was diving on the HMHS Letitia shipwreck in Halifax Harbour, Nova Scotia, one of Canada’s Maritime provinces. The British hospital ship, which lies near a gray seal colony, ran aground and sank in 1917 while returning from Liverpool, England, with wounded Canadian soldiers. 

Our group of six researchers back rolled off the vessel near Jupiter, Florida, and began our descent to the sandy bottom nearly 80 feet (24 meters) below. As the wreck became visible, our team streamlined into formation to begin our task: searching for goliath groupers. 

Piers and docks often act as reefs and harbor an abundance of shallow-water fish. These places were not designed to attract animals, but they have since become safe havens. Read more about the importance of piers and docks for marine life.

Fish completely enclose me. Their tiny, silvery bodies twinkle in the half-light as I float suspended in the center of a sphere of clear, warm water. I feel like I am inside a disco glitter ball. 

Seagrasses have evolved to thrive in marine environments — adapting to shallow, salty or brackish habitats at least three different times over 100 million years.

Conch snails are remarkable creatures with a set of eyes, a nose (sort of), a mouth and one foot. And because they’re slow, conches are commonly picked up and are a considered a delicacy in some regions.