Madfish Bay
William Bay National Park
How to Get There - From the centre of Denmark, head west along South Coast Highway until you see the signs for William Bay National Park. Turn left onto William Bay Road and follow this all the way to the parking area for Greens Pool. Turn left, with Madfish Bay located a further one kilometre down the road, with a well signed car park at the end of the road.
The Snorkel - With a family holiday booked in for the end of January in Denmark, I had a close eye on the weather to see if we would get any warm days that would be perfect for a beach visit. You never quite know on the South Coast, even during summer, so I was relieved to see that we would have at least one day in the high 20s to spend a few hours relaxing on the beach and snorkeling. I had my sights set on Peaceful Bay as a snorkeling destination after seeing a video on the WA Snorkeling FaceSpace page, but after our AirBnB host suggested Madfish Bay, that turned out to be an easier proposition to the rest of my family given the shorter drive.
I'd known about Madfish Bay prior to this visit, having ridden past on the Munda Biddi in 2021, and had a peek during previous trips, but it wasn't high on my radar as a snorkeling site. Having a closer look on Google Maps, it looked like I was wrong, with a sheltered bay, small island, and dark patches that might be fun to explore. My sister agreed with the plan, and after a lazy morning eating pancakes and playing board games, we headed out from Denmark to William Bay National Park. I'd seen photos from early January showing how busy the park was, and seeing a few parked cars on the entry road in was a bit of a worry, but as we approached the main Greens Pool car park, it was an acceptable level of busy. Madfish Bay is located about a kilometre further along the road, and when we arrived I was happy to see that the car park was relatively empty. My niece and I went off to suss out the best place to setup base, as we had been told that you can wade across to the island.
While there were some people doing that, it was agreed that it would be best to setup the beach shelter on a section of beach closer to the car park. With Caris safely out of the UV under the shade of the shelter, I got out my snorkeling gear and underwater camera, eventually joined by one of my nieces. I had made a plan in my head to explore the western side of the bay, sticking close to the shore as it looked like the middle was just bare sand. Walking closer to the small inlet created by a small stream, the water temperature wasn't as cold as I was expecting. Sitting down in the water to put my fins on, it wasn't breathtakingly cold, just an initial shock. With niece in tow, we set off in shallow water, eventually reaching the edge of the granite where we saw our first clumping of rocks, sea weed, and fish. It was similar to some of the areas off Rottnest Island, where you have to watch your body dragging on the rocks as you navigate around the shallow waters.
Exploring the little bay where a small creek flows down from the hills above, we saw a few fish hanging around including the first of many Zebrafish, and a couple of King George Whiting. Unfortunately my mask kept fogging up, but being in shallow water, I stopped to see what I could do (I've since burnt off the silicone layer and it's a night and day difference). I also remembered to pre-apologise to my niece for any accidental kicks to the face with my flippers, and we moved on. Leaving the small bay, we rounded along the edge of a granite slope that fell off into the water, and the water became a bit deeper, and colder, along with the sea grasses becoming more plentiful. After seeing a bit of life around here, it was time to cross the barren sands and make for the edge of the island. Hoping to see something cool in the open waters like a stingray, I was left disappointed. We reached the other side and explored the larger boulders, finding some shells and a few lonesome fish. At another mask cleaning stop, my niece said she was cold and was going to head back, so we made our way to the sand bar.
I was keen to explore a bit further, so when she was safely on two feet and heading back to the start, I continued along the shallow waters on edge of the island. This is where things picked up significantly in terms of cool finds. A narrow channel between the island and a large boulder was home to a school of Zebrafish, a Redlip Morwong, and the occasional Banded Sweep. Doing a loop around the boulder, I then continued towards where the calm waters meet an opening in the bay. With stronger currents, I timed my explorations into the shallow parts, and eventually found a fun area filled with Zebrafish, an Old Wife, Scalyfins, and a plump looking Globefish, a variety I'd only ever seen washed up on beaches. Wanting to keep going across the bay and explore more, I heard voices, and it was my other nibblings yelling at me from their exploration of the island. They let me know I was going to be late for a board meeting I had on, so I thanked them, and walked back to the start. I could have spent another hour in the water heading to the eastern side of the bay, but 90 minutes was good enough, and I have an excuse to come back now.
Final Thoughts - Another fantastic little snorkeling spot near Denmark explored, don't let my lack of seeing any marine life put you off, I'm sure there's plenty to see here. I was told that nudibranches can be found here, and I'm sure there's plenty more waiting to be discovered.
Even if you're just looking for a quieter alternative to Greens Pool, Madfish Bay is a good option, which as I said is a bit surprising given it's well signed as you head into William Bay National Park.
Get out there and experience it!
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