Algal growth over dead coral prevents coral recruits from settling and re-establishing the coral reef. Algae ecosystems support less diversity of life. This year is predicted to be a bad year in the Asia-Pacific for Coral Bleaching so keep an eye out!
Image by Jonathan Franks, University of Pittsburgh.
The freshwater red alga, Caloglossa, seen through polarized light.
A live desmid, a type of green algae found almost exclusively in fresh water, at 80x magnification. 5th place in the 1991 Nikon Small World Competition.
Plankton blooming off the Falkland Islands creates bright blue swirls in the Atlantic.
Phytoplankton, you damn fine.
Thanks for making most of the world’s oxygen and being the basis of the marine food web. That’s very kind of you.
Phytoplankton never looked so sparkly. These diatoms, or single-celled algae species, glitter under the microscope like tiny jewels. Diatoms form the basis of many a marine food chain, and they’re protected by cell walls made of silica, seen here. When diatoms die, their cell walls form diatomaceous earth, a sediment used in pool filters and some kitty litter. Researchers use diatom deposits as one way to understand the conditions of ancient lakes and bogs.
Parrotfish are named for their dentition, which also is distinct from that of other labrids. Their numerous teeth are arranged in a tightly-packed mosaic on the external surface of the jaw bones, forming a parrot-like beak with which they rasp algae from coral and other rocky substrates (which contributes to the process of bioerosion).
Although they are considered to be herbivores, parrotfish eat a wide variety of reef organisms, and they are not necessarily vegetarian. Species such as the green humphead parrotfish (Bolbometopon muricatum) include coral (polyps) in their diet.
Their feeding activity is important for the production and distribution of coral sands in the reef biome, and can prevent algae from choking coral. The teeth grow continuously, replacing material worn away by feeding.
One parrotfish can produce 90 kg of sand each year!!!
Toxic Seaweed Poisons Coral Reefs on Contact - By Daniel Strain, ScienceNOW
“Attack of the killer seaweed” may sound like a cheesy horror flick, but for many coral species, murderous multicellular algae have become real-life villains. A new study of reefs in the South Pacific suggests that some algae can poison coral on contact. This chemical warfare may be increasing the pressure on struggling reef communities worldwide, researchers say.
Along the reefs dotting Fiji, overfishing has pitted corals against algae in a battle royale. On swaths of coastline where fishing is restricted, corals such as the tall and branching Acropora millepora rule, says study co-author Mark Hay, a marine ecologist at the Georgia Institute of Technology in Atlanta.
But where Fijians spear lots of herbivores such as bird-beaked parrotfish, few fish remain to prune back the region’s seaweeds, a blanket term for many types of big algae. These algae then creep in, extending their tendrils over close to 60 percent of the ocean bottom, Hay estimates, and turning waters a sludgy green. Such “seaweed-covered parking lots” aren’t unique to Fiji, either, he says.
Komodo ‘11: Day Six: White Sands
Orang Utan Crab [Achaeus japonicus] - decorater crab.
Komodo ‘11: Day Four: Muck Dive
Phyllodesmium longicirrum - Ceras showing the white ducts of the digestive gland radiating out to the brown “gardens” of symbiotic zooxanthellae.