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.
Black triggerfish are one of the most common fish on the reef, at least in certain areas. They are unremarkable in appearance being mostly black with bright, pale blue lines at the base of the dorsal and anal fins (top photo).
They are usually seen in large groups, moving through the water as they feed on plankton and algae (middle photo).
But when they’re agitated, bright blue lines radiate from around the eye. The more agitated, the more coloration, until they can appear like the fish in the bottom photo, with blue-green lines over the whole body.
I saw these black triggerfish clustered in a very tight ball and wondered if they were feeding or being fed upon. Many of the triggerfish were showing colors that indicate arousal or agitation, but I didn’t see anything conclusive either way and my attention was quickly distracted when I saw this mysterious tube.
Another post based on the theme of this week’s WordPress Photo Challenge, which is ‘Silence.’
It’s not unusual to see fish feeding while snorkeling, but on this day the numbers doing so, up near the surface, were large. These are mostly Hawaiian sergeants and black triggerfish, with a few indo-pacific sergeants amongst them.
By easing myself slowly toward them, they weren’t unduly concerned, parting as I got close and returning as I passed. I felt like I was swimming in an aquarium, a quiet environment without the usual noises of everyday life.
Most of the time, black triggerfish look like the lower photo, a fairly uniform black, apart from two bright pale blue lines at the base of the dorsal and anal fins. However, when they become aroused or agitated, their colors can change, and this color transformation can happen very quickly. Sometimes it’s just the brilliant blue lines radiating from the eyes, sometimes the flush of yellow or orange on the sides, sometimes the blue-green lines along the side.
This black triggerfish gave me the full display, and rather than swimming off, it hung around and presented a broadside view. It’s possible it was defending its territory or perhaps some eggs.
I took the photo and swam on, not wanting to bother the fish more than I apparently already had.