A boring sponge

Not just any old sponge that is a bit tedious, but the Red Boring Sponge.

It's called the boring sponge as it drills into coral and sea shells. The sponge breaks down dead and diseased (and sometimes live) coral.

In "normal" conditions they play an important part in the reef, recycling calcium carbonate. But if the coral is struggling due to high temperatures or pollution, the boring sponges can erode the reef faster than the corals can replace it. #scubadiving