Published in Scuba Diver Asia-Pacific Jan 2024

by Nigel Marsh and Helen Rose

We had only been underwater for five minutes when we stumbled across a fish we have wanted to see for decades, the rare whitespotted frogfish. This small and well camouflaged frogfish is only found in southern Australia and we were delighted to observe and photograph it. However, it was not the only unique endemic species we saw, as we encountered a whole host of exotic marine life while exploring the wonderful jetties of the Yorke Peninsula, South Australia.

The Yorke Peninsula is located west of Adelaide and is flanked by the Gulf of St Vincent to the east and the Spencer Gulf to the west. First colonised by European settlers in the 1840s, the area quickly became an important agricultural district, which required the building of dozens of jetties for the loading of produce. Today only a handful of jetties are used for trade, the rest are now popular with anglers and divers.

While you can dive just about any jetty on the Yorke Peninsula, some are better than others, and on a recent trip to this area we explored three of the best – Port Hughes Jetty, Port Victoria Jetty and the famous Edithburgh Jetty.


The Port Hughes Jetty is located near Moonta, a pretty town on the western coast of the Yorke Peninsula. The jetty is 200m long and has access stairs about 100m from the car park that make for an easy entry and exit.

Once in the water we descended to the bottom, only 3m below, and started to explore the sand and seaweed covered bottom under the jetty. We quickly spotted ornate cowfish, bridled leatherjackets, ringed pufferfish, blue weed-whiting, magpie perch, western talma, Tasmania blennies and many other endemic temperate reef fishes. Crabs were everywhere; spider crabs, hermit crabs and also a few sponge crabs, slowing walking across the bottom with oversized sponge hats.


Rocks, old pylons and other debris littered the bottom under the jetty, and we closely inspected these objects as this is where the more unusual critters hide. These objects sheltered southern blue-ringed octopus, Tasmanian clingfish, painted stinkfish, crested triplefins, nudibranchs, brittle stars, seastars, sea cucumbers, sculptured blennies and southern pygmy leatherjackets. We photographed all these creatures, but what we were really hoping to see were frogfish and pipefish.

We spotted the first frogfish only five minutes into the dive, the lovely little whitespotted frogfish. While endemic to southern Australia, it is mostly seen in this area. Growing to 10cm long, the whitespotted frogfish is not an easy fish to find, as not only do they have camouflaged skin patterns, they also like to hide. We only observed and photographed this cute frogfish for a few minutes before it got camera shy and disappeared under a rock. Fortunately, this was not the only whitespotted frogfish that we found, as we spotted another three on this dive, and then another two the next day.

As we got deeper, depths under Port Hughes Jetty vary from 2m to 7m, the growth on the pylons changed from seaweed and algae to spectacular displays of soft corals, ascidians and multi-coloured sponges. We closely inspected many of these pylons to find blennies, triplefins, seastars, nudibranchs and many decorator crabs.

The fish life also increased as we got deeper, with the reef fish becoming more prolific and joined by schools of bullseyes, scad and snook. We also encountered other endemic fish like moonlighters, globefish, southern cardinalfish, wavy grubfish and bluespotted goatfish. At one point a southern eagle ray gliding around on the edge of the visibility.

Five species of endemic pipefish can also be seen at Port Hughes Jetty, but hiding in the seaweed they are not easy to find. It took us almost an hour to find our first pipefish, a little gulf pipefish. This species is only found in South Australia, and growing to 10cm long and looking like a piece of seaweed, they are not easy to see. However, we managed to find several more of these cute little fish once we knew what to look for.



Port Victoria is another small town off the west coast of the Yorke Peninsula. Its jetty is not as popular as the other two covered in this article, even though it is the longest jetty at 300m long, and also the most sheltered, located behind Wardang Island. We probably would have missed it too. It was only because we had to visit the town to get airfills at the Port Hughes Kiosk, that we checked it out, and we were very glad we did.

This jetty has a ramp for entry and exit, unfortunately it is 200m from the car park, so a fair walk. However, it was worth the effort as under the jetty are dense beds of seagrass, masses of fish and also many surprises. We enjoyed a very cruisy ninety-minute dive as we explored this jetty, going no deeper than 4m.

Within a minute of descending we found a clump of seaweed that was home to shorthead seahorses and several spotted pipefish. The shorthead seahorse is only found in southern Australia and grows to 10cm long. They are a shy and cryptic seahorse that hide among seaweed and algae. They breed over the summer months, and one male we spotted had a very swollen belly, a sure sign that he was pregnant and ready to pop.

After photographing the seahorses, we moved onto the spotted pipefish. This is another endemic pipefish that likes to hide in the seaweed, fortunately growing to 27cm long they are a little easier to spot. However, they are difficult to observe and photograph as they constantly weave in and out of the seagrass. One of the ones we found was also inflected with several isopods that were attached to its snout!

We saw all the typical reef fishes we had seen at Port Hughes Jetty, and also zebrafish, yellowhead hulafish and several different weed-whiting species. One of the reef fish that we really loved at this site was all the ornate cowfish. We saw both males and females, that have different colour patterns, we also spotted groups of juveniles.

Towards the end of the dive we encountered a few of the larger residents. First up was a southern fiddler ray, relaxing in the seagrass. Then just before we surfaced we found a giant cuttlefish tucked up in the seaweed.



The Edithburgh Jetty is easily the most famous and most popular dive site on the Yorke Peninsula, and for good reason. This jetty is 180m long, and the entry stairs are only 20m from the car park, making it one of the easier spots to dive. However, the main attraction is all the marine life that gathers under the jetty, including a host of weird and wonderful species.

On our first dive we were greeted by an unexpected resident, an Australian fur seal that had been hanging around the jetty for weeks. We spent several minutes playing with this friendly seal as it zoomed between the pylons.

We then did a slow circuit of the jetty, seeing a great range of reef fish, a southern eagle ray and also many invertebrate species. Depths under this jetty vary from 2m to 9m, and its pylons are completely covered in sponges, ascidians, algae and seaweed.

However, there is something very different about this jetty, it has a solid deck, with no light filtering through. This makes it a little gloomy at times, and also means that no seaweed grows under the jetty. However, the side effect of this is many crustaceans and cephalopods are about during the day, and this twilight zone attracts many unique fishes.

It didn’t take us long to find two more whitespotted frogfish, and we also found another rare endemic frogfish, the prickly frogfish. Two other unique frogfish, the tasselled and rodless frogfish, are also found under this jetty, and while we searched high and low, we couldn’t find these elusive fish. Instead we found shorthead seahorses, painted stinkfish, ornate cowfish, octopus, crabs, squid, cuttlefish and a large estuary catfish. On a previous visit we also found a beautiful leafy seadragon.

As wonderful as the day dives were under Edithburgh Jetty, it was after dark when it really comes alive. This is when more crustaceans and cephalopods emerge. Crabs and shrimps are out looking for food, calamari squid dart about and southern blue-ringed octopus roam the bottom. We spotted a southern dumpling squid and two western shovelnose stingarees feeding. However, the highlight was three super cute striped pyjama squid. These gorgeous black and white striped cousins of the cuttlefish hide in the sand by day and emerge at night to feed.

You can dive these jetties year-round, and we enjoyed 8m to 12m visibility in March and 21°C water. It naturally gets a lot colder over winter, though great marine life can be seen under these jetties at anytime. And being a peninsula means there is somewhere to dive no matter the weather. The only limiting factor to diving the Yorke Peninsula is no dive shops, you will need to hire gear in Adelaide. However, you can get airfills at Port Victoria and Edithburgh.

We had a wonderful time exploring these three special jetties, and it will not be long before we are back to explore these and more of the jetties of the Yorke Peninsula.