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Over the years I have travelled to several destinations around the planet hoping to see schools of Scalloped Hammerheads. Unfortunately, these trips have always been unsuccessful, either no sharks or only a few sharks that kept well away from me and my camera. So it was a great surprise when I heard that a school of juvenile Scalloped Hammerheads had recently been spotted at a local beach on the Gold Coast.

The Scalloped Hammerhead (Sphyrna lewini) is one of the nine species of shark with that distinctive hammer-shaped head. The shark is a coastal pelagic species, found around the planet in tropical and warm temperate waters and they are known to form into vast schools. The Scalloped Hammerhead grows to 3.5m long, and has been heavily targeted by fishers for their fins, which has seen their numbers plummet and the species listed as Critically Endangered.

In Australia the population of Scalloped Hammerheads is a little healthier, though largely unknown. They are a protected species, but still get killed by shark nets and fishers. Around the country there are a few locations where this species has been seen in small groups and schools, most notably Fish Rock at South West Rocks and Osprey Reef in the Coral Sea. Even at these hotspots encounters with Scalloped Hammerheads are seasonal and very unpredictable.

When I first heard that a school of Scalloped Hammerheads had been seen off Burleigh Heads on the Gold Coast, I dismissed it as a one off. However, obtaining more detailed reports, I learnt they were a group of juveniles and they had been hanging around the same spot for weeks. After seeing posts on social media of people snorkelling with the sharks over Easter, I knew I had to check this out. A week later I got my chance and drove down from Brisbane to see the sharks.

I arrived at Burleigh Heads before dawn, as I had been informed that dozens of snorkellers can crowd the spot and was told to get there early. However, there were already several people with snorkelling gear getting ready. Five people managed to enter the water before me, and I quickly followed. It was a perfect Queensland autumn day for a snorkel; warm, no wind, a small swell and the water was clear, around 12m visibility.

I headed out to where I could see the other snorkellers, seeing a few Common Stingarees, bream, goatfish and flatheads as I went. For several minutes I scanned the waters around me, but couldn’t see any sharks. Were they still here, had I missed them?

IMAGE BELOW - ONE OF THE JUVENILE SCALLOPED HAMMERHEADS

Suddenly several grey shapes appeared from the pre-dawn gloom. It was the sharks, and it was a sight I will never forget - a dozen beautiful Scalloped Hammerheads. I watched spellbound as the small graceful sharks heading straight towards me, cruising effortless over the sandy bottom. The sharks swam directly under me, 2m below, and then continued into the shallows. The encounter was far too quick, but I managed to snap a few images, proof that I had seen the sharks.

Only a minute later I saw them again, and this encounter gave me more time to appreciate these lovely little sharks. I did a quick count and worked out there were sixteen sharks cruising across the sand in formation. The sharks appeared to vary in size from about 1.1m to 1.5m long, and all the ones in this group were female.

Over the next thirty minutes, as the sun slowly rose on the horizon, the encounters got briefer and briefer, as the number of snorkellers increased. There must have been forty people in the water. Most were quite well behaved, happy to watch the sharks cruise around. Unfortunately, others were diving down and chasing them across the bottom. During this time the sharks seemed to split into smaller groups, scattered all over the sandy bottom.

To avoid the crowds, I swam wide and after ten minutes by myself I was rewarded with my own special hammerhead encounter. A group of eight sharks joined me and then slowly patrolled this area, allowing me to swim above them for around fifteen minutes. I got some good images during this time, and sadly noted that two of the sharks had fishing tackle in their jaws and one was trailing a heavy lead sinker. I would have loved to remove the sinker, but the shark was very nervous and kept its distance.

IMAGE BELOW - A GROUP OF EIGHT SCALLOPED HAMMERHEADS

As the morning wore on, more snorkellers joined the fray, and more of them were chasing the sharks. It was great to see so many people coming to see these little sharks, there must have been over one hundred snorkelers. However, there are always going to be the few that push the encounter too far and ruin it for others by attempting to touch the sharks or chase them to get that selfie. While all the attention obviously stresses the sharks, it has a lot less impact than fishing tackle. And after several weeks of snorkellers observing the hammerheads they were still here, possibly in reduced numbers, and they looked quite healthy.

After two hours in the water the visibility had decreased and I thought it was time to leave the sharks in peace. As I exited the water, I got a lovely last surprise when two hammerheads swam pass me in the surf zone, a nice farewell after an amazing experience.

Seeing this pack of juvenile hammerheads left me with many questions. I knew something like this had never been seen on the Gold Coast before, so I endeavoured to discover as much as I could about the sharks. Contacting a few Gold Coast locals, I discovered that the sharks were first seen around February 18 and were about 50cm long at the time, so most likely newly born. It was estimated that the school at this stage contained around 40 pups. However, with surf churning up the shallow gutter where the sharks were patrolling, few people got in the water with them at this time.

By the end of March small seas and light winds meant the water became calm and clear, allowing people to started snorkelling with the sharks. The hammerheads had grown to about 75cm long by this time, with the group containing around 30 sharks. A decrease in number could be either based on numbers being inaccurate and difficult to count, or some of the sharks already moving on (maybe the males) or possibly the sharks being preyed upon by larger sharks. When I snorkelled with them, they had been in the area for around eight weeks and had doubled, and in some cases tripled, in size. However, there appeared to be a lot less sharks, I only counted sixteen in the largest group I saw, but there could have been more.

IMAGE BELOW - SCALLOPED HAMMERHEADS PATROLLING THE SAND

But why were they here? The most logical answer is that the site was being used by the sharks as a nursery area, while they grow. A few juvenile shark species are known to use nurseries, often in mangroves, to keep them safe from predators when they are small. Scalloped Hammerheads give birth to live young over summer that are between 45cm and 50cm long, with their litters varying from 12 to 41 pups. It is known that Scalloped Hammerheads use nearby Moreton Bay as a place to give birth and as a nursery.

It is most likely that the juvenile hammerheads at Burleigh Heads are from the one litter. Why their mother decided to give birth to them at this spot is a mystery. While all the sharks I saw were female (I also confirmed this reviewing other people’s videos and photos) it is possible that males were also part of this litter and either moved away earlier, or stayed away from the females and avoided the snorkellers.

The day after I snorkelled with the sharks the weather turned nasty, with a large swell reducing the visibility to almost zero. For the next week strong winds and rough seas hit the coast, and the few brave souls that entered the water saw no hammerheads. The sharks had moved on to parts unknown. They have probably headed north to the warmer waters of the Great Barrier Reef for winter, but with little study of this species in Australia this is merely a guess.

Departing this nursery at Burleigh Heads, the hammerheads face a whole range of threats. They have to avoid the Queensland Government’s shark control measures – drum lines and shark nets that are deployed at many local beaches. They also have to avoid fishers and larger sharks that could make a meal of them!

We can only hope these small sharks grow to adults and produce their own pups in the future. Maybe one of them will also choose Burleigh Heads as a safe place to have it own litter and we can once again see a school of these wonderful little hammerheads.

IMAGE BELOW - SEEING THESE JUVENILE SCALLOPED HAMMERHEADS WAS AN AMAZING EXPERIENCE