Tag Archives: Coral

Watching an octopus

A day octopus in the waters off Hawaii

The easiest way to spot an octopus is to see it swimming (top photo). They’re not large creatures but they’re quite distinctive when they swim.

If they’re not swimming, one thing to look for is certain fish, such as goatfishes and jacks, just hanging around in a spot for no apparent reason. When these fish are hunting alone, they tend to be more active in probing the rocks and trying to disturb prey. But when they’re hunting with an octopus, they seem more content to let the octopus do the work and snapping up whatever emerges. I’ve found that goatfishes are particularly helpful as an octopus indicator.

A while back, there were videos online of an octopus apparently punching a goatfish. I wasn’t surprised by this. The octopuses I’ve seen don’t seem best pleased by the presence of goatfishes. Part of this might be down to feeling that the goatfishes are not pulling their weight in the hunt. But another factor might be that if goatfishes give away their position, for the octopus that can be fatal.

Octopus is a popular food in Hawaii and has long been so. If I’ve learned to look for goatfish as an indicator of their presence, then no doubt spear fishermen have too. These days, if I see an octopus when anyone’s spear fishing nearby, I don’t do anything to draw attention to it.

A day octopus in the waters off Hawaii

The morning dip

A whitetip reef shark passes below looking, I think, for a quiet place to get some rest.
A fourspot butterflyfish swims by a patch of cauliflower coral, some living, some dead. There are two spots on each side, but this fish was very small so the second spot was still filling in as space allowed.
A blue goatfish cruises by.
A green linckia sea star and lobster molt. Most green linckia have five arms but can have four or six. They’re able to reproduce by detaching an arm which will eventually develop into a new star.

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.

It wasn’t until I processed this photo of a goldring surgeonfish that I noticed the stocky hawkfish resting motionless below it.

Yesterday’s swim

A small shoal of convict tang feeding.
I think this is a spotted coral blenny on a head of purple cauliflower coral, and possibly a small trumpetfish.

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.

In short, it was a fairly typical swim.

A shoal of mackerel scad on the left with yellow tang on the right.
Little fish enjoy the comparative safety of the shallow water in the surge zone.
On the left, a fourspot butterflyfish and a cushion star. On the right, black triggerfish are cleaned by a Hawaiian cleaner wrasse.
Just before getting out I saw this small Pacific trumpetfish with goldring surgeonfishes.

The top of Two Step

Two Step is a popular snorkeling spot, next door to Pu’uhonua o Hōnaunau National Historical Park, otherwise known as Place of Refuge. It gets its name from one of the entry points to the water, where two flat lava ledges make it easy to get in and out. Well, fairly easy; there’s usually a crowd gathered around the steps so it can be a bit of a scrum. Also, small sea urchins sometimes lurk in hollows in the steps.

Once it the water, there’s room to roam. I like to swim the length of the bay and out a little bit, to where I can look down the coral slopes leading to the sandy floor of the bay.

Posted in response to Becky’s April Squares challenge theme of ‘Top.’ See more responses here.

Arc-eye hawkfish and bleached coral

This is a typical pose for an arc-eye hawkfish, keeping very still as it nestles in a head of cauliflower coral. But the coral is not well. This patch is mostly bleached. The causes of coral bleaching include warmer than normal water temperatures, pollution, and sunscreens containing coral-killing ingredients.

Because of this third factor, Hawaii has passed a bill which will ban the sale of sunscreens containing oxybenzone and octinoxate. This law goes into effect January 1, 2021. While this will help, it won’t do anything to keep harmful chemicals out of water runoff, and it won’t do anything to prevent the warming of the Pacific Ocean.

Last fall, we had a coral bleaching event here because of warmer ocean temperatures. It wasn’t as bad as feared, but still did damage to corals that were just recovering from previous bleaching events. There are one or two snorkeling sites here that I don’t visit anymore because the state of the coral is just too depressing. I’d like to think that this degradation can be reversed but, honestly, I’m not optimistic about that.