What? Animals in the sea armed with missiles? And thousands of them? Yes, you’ve read correctly. No, sea lions or dolphins have not been stealing Tomahawk missiles from any of the American navy bases. But did you know that jellyfishes, sea anemones and corals contain thousands of “miniature missiles” to kill prey and sting intruders? We will look at bit closer at this missile battery mechanism here.

How the corals get their algae. In the previous issue of X-ray Mag the problem of coral bleaching was discussed. Mechanisms were described which might provide resistance and protection to increased temperature and light intensities. It was stated that, due to rising sea-temperatures, the symbiotic algae that help supply nutrients to the polyps of the corals were dying off.

Can tropical stony corals adapt to bleaching?

Different conservation groups have the last couple of decades brought our attention to the destruction of the world’s tropical coral reefs. These reefs are visited by millions of tourists and are the livelihood for many more millions of people.

The exploitation of corals has depleted stocks all over the world. This is not only destroying the seafloor, but has a much wider impact. Corals are more valueable if they stay in the oceans rather than around someone’s neck. Coral reefs support more than 25 percent of all known marine fish species. As one of the most complex ecosystems on the planet, coral reefs are home to more than 4,000 different species of fish, and almost 5,000 species of corals, in addition to thousands of other plants and animals. Scientists estimate that coral reefs provide an economic benefit of US$ 375 billion each year to millions of people around the world. Besides from indirectly feeding people, corals also offer cures for illnesses. Add to that that coral reefs protect our coastlines.

Clownfish sea anemones usually live solitary lives. On many coral reefs there will normally be only one individual for each 50 to 100 meters, perhaps 10 to 20 meters of reef. But occasionally groups of up to several hundreds of clownfish sea anemones are found together within a small area in an assemblage we call anemone cities.

Scientists proposes saving corals for posterity by freezing samples of coral species in liquid nitrogen.

Researchers from the Department of Biological Sciences at the University of Essex have discovered a previously unknown coral reef in the Seychelles.

Imagine descending in a submarine to the ice-cold, ink-black depths of the ocean, 800 metres under the surface of the Atlantic. Here the tops of the hills are covered in large coral reefs. NIOZ-researcher Furu Mienis studied the formation of these unknown cold-water relatives of the better-known tropical corals.

Coral reefs depend on fish to graze the seaweeds with which the corals compete, and without such cleaning, the reefs decline as corals are replaced by seaweeds. But the species composition of plant-eating fish is crucial as different fish consume different seaweeds.