Image of the Day: Coral Disease
Image of the Day: Coral Disease

Image of the Day: Coral Disease

A mysterious illness is causing tissue loss in many species.

Oct 7, 2019
Emily Makowski

ABOVE: A diseased maze coral (Meandrina meandrites) whose skeleton has turned partially white
JAY HOUK

Stony coral tissue loss disease is killing at least 20 species of Caribbean corals, according to Blake Ushijima, a postdoc at the Smithsonian Marine Station in Fort Pierce, Florida. The disease was first identified off the coast of Florida in 2014. Although the damaged corals may look similar to ones that have undergone bleaching from warm ocean temperatures, the symptoms are different. Bleached corals are pale because they lose symbiotic algae, while stony coral tissue loss disease (SCTLD) turns corals white from the destruction of soft tissue that eventually kills the animal. “The white portion is actually just exposed skeleton, which is all that is left after the disease infects many coral colonies,” Ushijima tells The Scientist

The left photo shows a fragment of Pseudodiploria strigosa (brain coral) with an SCTLD lesion on the lower left corner. On the right, SCTLD spread to the entire fragment 3.5 days later.
KELLY PITTS



The pathogen that causes SCTLD is unknown, but researchers have determined that bacteria play a role in the disease’s progression. Ushijima and other researchers are developing probiotics from disease-resistant coral colonies to treat diseased corals and protect ones that haven’t been infected. 

A healthy great star coral (Montastraea cavernosa) from a quarantine facility at the Smithsonian Marine Station
Blake USHIJIMA

Emily Makowski is an intern at The Scientist. Email her at emakowski@the-scientist.com