Cushion stars (Culcita novaeguineae) look just like their name implies – small but comfy-looking cushions that would not look out of place on your couch. However, these cushions would move around on their little tube feet, which might be a bit disconcerting.
They come in several colors including red, yellow, and tan and there’s often quite a bit of variety in their markings. Cushion stars feed on living coral, which they eat by pushing their stomach out and consuming the coral where it sits.
If you like graphic violence, you’re at the right place today. This is a triton’s trumpet sea snail devouring a cushion star, which has been turned on its back. These snails are the largest in the island and feed on echinoderms, which include stars, cucumbers, and urchins.
Posted in response to Becky’s October Squares challenge theme of ‘Kind.’ See more responses here.
This week’s Friendly Friday challenge theme is ‘Morning Rituals.’ See more responses here.
Most mornings, I try to get in the water, as conditions and schedules allow. Morning is the best time for snorkeling as the water is usually calmer before the wind picks up as the day wears on. Visibility can vary from day to day and it can help to check surf reports to see if there are any swells moving in. But calm water doesn’t guarantee good visibility just as swells don’t always mean bad visibility. There’s only one way to be sure and that’s to jump in.
My favorite thing about snorkeling is that every day is different and I never know what I’ll see. Going to the same spot means I become familiar with some of the regulars, but there are always transient creatures passing through including rays and dolphins. And while those big creatures are great to encounter, it’s equally interesting to watch the activities of smaller fish and marine invertebrates.
It’s a rare day indeed that I don’t emerge prattling on about something I saw while I was in the water. And on those rare days, well, I’ve still had a good swim to set me up for the day ahead.
This is a second response to this week’s Sunday Stills challenge theme of ‘Waterworld.’ (See more responses here.) Yesterday, I posted about the movie Waterworld. Today, it’s a probably more expected response.
These are photos I took during my swim yesterday. Visibility in the water was patchy with some good areas and some not so good. I didn’t see anything startling, though the mackerel shads aren’t a common sight. Last time I saw such a shoal there was a great barracuda lurking on the other side. I looked around and, sure enough, there was another one looking interested as it cruised low down, too low for a decent photo.
The other oddity was in the photo at left. I saw what I think is a spotted coral blenny on this patch of cauliflower coral, and snapped a quick photo before it took off. But it was only when I processed the photos that I saw something else, to the left and slightly below the blenny. I think it’s a small trumpetfish, but it could be something else. A lot of small fish and other creatures hide in coral heads so I must pay more attention from here on.
Triton’s trumpets are snails and their shells are the second largest in the Indo-Pacific. They can attain a length of 20 inches. The colorful shells are also quite beautiful, especially when they catch the light filtering down from above.
These snails eat echinoderms including Crown-of-Thorns stars, which feed on corals.
Crown-of-thorns sea stars (Acanthaster planci) feed on coral and, because of this, are considered a menace to the health of coral reefs. Up to a foot-and-a-half across, they can have as many as 19 arms and are covered by venomous spines. If this all sounds like this creature is a nasty piece of work, the good news is that it has not caused extensive damage to the reefs here in Hawaii.
The crown-of-thorns does have predators, one of which is triton’s trumpet (Charonia tritonis). These large triton snails, up to 20 inches long, feed on echinoderms including crown-of-thorns sea stars. When they scent prey, they will take off after it and are considered speedy for a snail. When a triton’s trumpet catches its prey, it grips it with its foot and applies saliva that causes paralysis, which allows the snail to consume its meal without further drama.