Species of the month: Giant Cuttlefish – Whyalla’s stunning cephalopods

Species of the month: Giant Cuttlefish – Whyalla’s stunning cephalopods

I recently took a week off to visit Whyalla in the Eyre Peninsula of South Australia, something I had been wanting to do for several years. Why Whyalla? Each winter, from May to July, thousands of Australian Giant Cuttlefish Sepia apama gather there to breed, and this is the only place in the world where such an event is known to take place! From Mount Gambier to Whyalla is quite a drive (about 830 km), but with other travel plans this year cancelled because of COVID it seemed like the perfect time to experience this natural phenomenon in my own state.

Even with a brand new wetsuit and extra rented gear the icy water kept snorkel times to under half an hour. But that was plenty of time to see 10, 20, 30, 40 – actually, I quickly lost count how many cuttlefish I saw each time I got in the water. It was spectacular!

Check out this incredible clip from Planet Earth: Blue Planet II showing a dramatic colour changing abilities of cuttlefish.

Cuttlefish are definitely fascinating creatures. Here’s a few fun facts:

  • Cuttlefish have W-shaped pupils! This shape means they can see behind them.
  • Cuttlefish have three hearts! Two hearts pump blood to the gills, while the third pumps oxygenated blood to the rest of the body.
  • Cuttlefish have complex cognitive abilities and have been shown to decide to eat less during the day if they know a big meal is coming in the evening. 

This video shows the most accessible location to witness the cuttlefish aggregation. As you can see, it’s an easy walk from the carpark over flat rocks to the water where you swim with countless cuttlefish. There’s no need to scuba dive as the cuttlefish hang out on the rocky reef in about three metres of water so you can see them well snorkeling. I highly recommend giving it a go next winter!

Rose Thompson