Stephen Thurstan was doing laps in Kiama’s Continental rockpool, on School Flat, when he spotted a most unusual fish.

“I came back with my underwater camera the next day and found it again just a couple of metres away, sitting next to a mass of white bubble shell eggs,” he says.

“I took a few pics and sent them to the Redmap website for expert identification.”

Redmap is a government and university supported citizen science project that invites Australians to share sightings of marine species that are ‘uncommon’ to their local seas.

Over time, Redmap will use this ‘citizen science’ data to map which Australian marine species may be extending their distribution range in response to changes in the marine environment, such as ocean warming.

The result came back just as Stephen expected. His fish was a Striped Anglerfish (Antennarius striatus), an unusual looking fish which grows to a maximum length of approximately 20cm, with an enlarged third dorsal fin. Their first dorsal fin is also modified to serve as a luring tool (looks like a worm) to capture small fish.

One of Stephen's photos

“I’ve been a keen diver for so many years and to see this fish was a real buzz,” says Stephen, an experienced underwater photographer who has dived many places around the world.

“I was thrilled to see such an interesting fish in our local saltwater pool.

“The seagrass, rocks and algae in the pool make it a great habitat for many species of fish, molluscs and crustaceans. I'm sure many people appreciate seeing these while doing laps. And it’s a safe place for kids to explore with a mask and snorkel.”

Stephen says Kiama’s rockpools are such great assets for our town and that we should work hard to keep them alive and healthy and not think about introducing chemicals or killing the weed.

According to a Department of Primary Industries spokesperson, the Striped Angerfish is always the highlight of any dive. They are often found in warmer tropical waters and their colour can vary greatly from white, yellow, orange, black, grey or brown, often matching the colour of surrounding sponges.

Another angle

The spokesperson says that when the seawater runs as hot as it has been recently, “the East Australian current can end up in strange places and will bring all sorts of things down the coast”.

“But not big things,” says the spokesperson, “as they prefer the cold water.” Good to know.

If you spot an unusual fish or crustacean, you can log it here.