When threatened, puffers puff themselves up by gulping down water and pumping it into their highly expandable stomachs, making their bodies difficult for predators to swallow. One spiny puffer species, called the balloonfish, swells to about 3 times its usual volume. Most of that increase is thanks to the stomach, whose many folds let it expand by 50 to 100 times! At the same time, hundreds of sharp spines all over its body stand erect.
The Marine Science Institute's monthly column, Science and the SeaTM, is an informative and entertaining article that explains many interesting features of the marine environment and the creatures that live there. Science and the SeaTM articles appear monthly in one of Texas' most widely read fishing magazines, Texas Saltwater Fishing, the Port Aransas South Jetty newspaper, the Flour Bluff News, and the Island Moon newspaper. Our article archive is available also on our website.
What is the greatest size and age a living thing can achieve? Seagrass meadows may hold the answer.
Seagrasses are flowering plants that have adapted to live submerged in the ocean. Although there are only about 60 species, they cover a vast amount of the world’s temperate and tropical coastal areas.
Watch a stingray glide over the sandy sea floor and you can tell it’s in hunting mode — but the tricks the ray is using to search for prey may not be so obvious.
A stingray’s eyes are located on top of its wide, flat body, while its mouth is on the underside. This may not seem like the best design for a fish that has to scan the murky bottom for hidden clams and crustaceans. Luckily, rays are endowed with remarkable sensory abilities that make them ace hunters.
In Antarctica’s coastal waters, a group of perch-like fish called icefish dominates. The water column in these frigid seas is filled with tiny ice crystals, and fish are constantly exposed to ice through their gills and skin. They even ingest ice crystals when they eat and drink.
For years, scientists believed all sponges were filter feeders that trapped and fed on bacteria from water they pump through their bodies. But in 1995, researchers discovered that certain species of sponge enjoy meatier meals.
Since satellite monitoring began in 1979, sea ice in the Arctic has been on the decline, shrinking by about 10 to 12 percent per decade. In the summer of 2007, Arctic sea ice cover shrank to an unprecedented low. At this rate, researchers project that the Arctic may experience a summer completely devoid of ice by the end of the century.
Vast expanses of sea ice make the Arctic and Antarctic oceans perilous and inhospitable, but they’re also vital guardians of Earth’s climate.
Sea ice forms when ocean water is cooled to the freezing point by cold polar air. Freezing begins in fall, when the amount of light from the sun decreases, and ice continues to expand and thicken during the dark winter months. When summer returns, the sun’s energy warms the surface of the ice, causing portions of it to melt.
You might imagine marine snails crawling around on the sea floor. But thanks to a unique adaptation, one family of snails lives life at the top of the ocean.
Violet snails cannot swim but they can construct “rafts” from clusters of air bubbles, and these rafts allow the snails to float at the water’s surface. They float throughout tropical and subtropical oceans, preying on an abundant food source − jellyfish.
If you think a fish out of water would be easy to catch, you haven’t encountered the Pacific leaping blenny.
This acrobatic, slippery little fish can be found hopping and climbing around the rocky coasts of Guam. A diminutive 1½ to 3 inches in length, it spends almost all of its time on land — a curious and unique lifestyle among marine fish. To navigate its rocky habitat, the blenny has developed a tail-twisting move that allows it to leap from rock to rock with impressive distance and agility.
Wind and gravity aren’t the only forces that move the ocean’s water — there’s also a conveyor belt at work.
The Great Ocean Conveyor works by thermohaline circulation — water movement caused by density differences. The oceans are layered in water masses that differ in temperature and salt content. Lower temperatures and higher salinity translate to greater density.