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Drifting slowly across the sandy bottom I was hoping to see some stingrays, when suddenly in the distance I could see a large dark shape swimming towards me. At first, I couldn’t work out what it was, but then my heart skipped a beat when I saw a large shark with a high dorsal fin and a broad-shaped head. It’s a Great Hammerhead I thought with great excitement. Several seconds later my heart rate returned to normal when I realised it was no hammerhead, and not even a shark, just a large shovelnose ray. I am sure I am not the only one to have confused a shovelnose ray for a shark, as this group of fishes are some of the most misidentified of all the rays.

The rays are a very large and complex group of fishes, containing over 633 species in 26 family groups. One of the most interesting, and confusing, group of rays are those with a shovel-like heads. There are actually four families of shovelnose rays, called the wedgefishes, guitarfishes, giant guitarfishes and banjo rays. And with the families being revised, reclassed and renamed over the last few years I thought it was time to sort out the shovelnoses.

Now for starters lets set the record straight, these rays may have a body like a shark, but they are definitely rays, as they have the two key distinctive features of a ray - pectoral fins that are fused with the head and gills on their underside. Problems arise when people miscall them shovelnose sharks or guitar sharks. These names are incorrect and are best avoided. I have even met people that seem to think they are a type of hybrid – the result of a shark and a ray having interspecies sex? A wonderful theory, but also incorrect.

Part of the problem is their common names. As calling them wedgefish and guitarfish, instead of wedge rays and guitar rays, allows people to put their own spin on things. And as they do look more shark-like than ray-like this is completely understandable. I for one would love to see their common names changed to make their status as rays very clear.

All four families of shovelnose rays share similar characteristics. Having a shark-like body they swim like sharks, using their tails for propulsion, rather than their pectoral fins like stingrays and manta rays. They are all bottom dwellers, feeding on small fish, molluscs, crustaceans and other invertebrates they dig out of the sand. These rays also rest on sandy bottoms, often covering themselves with sand to conceal their presence. They all give birth to live young, with small litters of generally two to ten pups, but a few have up to twenty young. Shovelnose rays have a slow growth rate, mature late and are preyed upon by sharks and fishers, which has seen many of them sadly decline in number.

When I first learnt to dive, almost forty years ago, there was only two recognised families of shovelnose rays – the sharkfin guitarfish and the shovelnose rays, both these names are no longer in use. However, over the last decade researchers have used DNA technology to study them at a molecular level, which has led to many more species being identified and the shovelnose rays being regrouped and reclassified in four family groups.

IMAGE BELOW - WHITE-SPOTTED WEDGEFISH (photo by Nigel Marsh)

THE WEDGEFISHES (Family Rhinidae)

The ten members of this family are typically large, with most between 2m and 3m long. Wedgefishes are found in the tropical to warm temperate waters of the Indo-West Pacific region, but two members of this family inhabit the waters of the Eastern Atlantic. They all have two large dorsal fins and a powerful tail, and most have one or more rows of prominent thorns on their head. Wedgefish typically have a large wedge-shaped head, but two members have a more rounded head. These rays vary in colour from brown to grey, and most have a pattern of white spots decorating their head and back.

In Australian waters divers can see three members of the wedgefish family, with the White-spotted Wedgefish (Rhynchobatus australiae) the most common and widespread. Also known as the Bottlenose Wedgefish, this large ray grows to 3m in length. An inshore species, the White-spotted Wedgefish is found in northern Australia, from Shark Bay in Western Australia to South West Rocks in New South Wales. This species is occasionally seen on the Great Barrier Reef, most commonly on the SS Yongala and around Lady Elliot Island. However, it is far more common in southern Queensland and northern New South Wales, especially over the summer months when large numbers migrate to the area, most likely to breed. Wolf Rock, HMAS Brisbane, Cook Island and Julian Rocks are all good spots to see this species, but the best site to see numerous White-spotted Wedgefish is Manta Bommie off Brisbane. On most dives you can see two or three, but sometimes dozens are seen lazing on the bottom. I have even witnessed mating behaviour at Manta Bommie, watching a small male (2m long) nudging the side of a much larger female (3m long). I thought I was going to be extremely lucky and observe the rare event of rays mating, but after nudging the female several times, she rejected his advances and swam off, with the male in hot pursuit. Nearly all the White-spotted Wedgefish divers encounter in Australia are female, but we have little understanding of their population dynamics or migrations.

White-spotted Wedgefish appear to have very individual personalities, as they all react differently to divers. Some are very shy, and take off as soon as they see a diver. Others will let you get within a few metres before they get nervous and swim away. While some don’t seem to care about divers and will let you get right up beside them. Some are curious of divers and will even swim towards a diver to see what they are. Often the best time to sneak up on a White-spotted Wedgefish is when it is getting cleaned by Common Cleaner Wrasse.

IMAGE BELOW - BOWMOUTH WEDGEFISH (photo by John Gransbury)

The very similar looking Eyebrow Wedgefish (Rhynchobatus palpebratus) is also found in the tropical waters of northern Australia. This species grows to 2.6m and has a narrower snout and different spot pattern, but telling the difference between the two species is very difficult.

The only other member of the wedgefish family that divers can encounter in Australia is the very rare and very strange Bowmouth Wedgefish (Rhina ancylostomus). Also called the Shark Ray, this distinctive member of the family is very prehistoric looking with a round head covered in rows of thorns. The Bowmouth Wedgefish grows to 2.7m in length and is found throughout the Indo-West Pacific.

Australia is one of the best places to see this bizarre ray, but even here they are rare. Found in tropical to warm temperate waters, divers have seen the odd one on Ningaloo Reef, SS Yongala, Lady Elliot Island and also off Brisbane. But the only spot where they make semi-regular appearances is at Wolf Rock off Rainbow Beach. This species is far more active by day than other wedgefish, and is rarely seen resting on the bottom. It is more likely to be seen swimming around, and appears to like areas with strong currents.

IMAGE BELOW - GIANT GUITARFISH (photo by Nigel Marsh)

THE GIANT GUITARFISHES (Family Glaucostegidae)

Growing to 2m to 3m in length, the giant guitarfish rival the wedgefish in size and are often confused. However, two main features help identify giant guitarfish, the location of the dorsal fins, set further back on the body and their distinctive pale translucent snout. The six members of this family are all plain brown in colour, with a row of short thorns along the back.

The only member of the family found in Australian waters is the Giant Guitarfish (Glaucostegus typus). This large ray grows to 2.7m in length and inhabits tropical inshore waters. In Australia this species is found from Shark Bay in Western Australia to northern New South Wales. They appear to like estuaries and bays, where the water is often murky, but the best place to encounter one in clear water is Heron Island. At Heron Island dozens of Giant Guitarfish often gather in the harbour, right under the jetty. However, they don’t always hang out here, and on my last visit to Heron Island the best place to see them was in Shark Bay, at the other end of the island. The ones I have encountered at Heron Island are very accustom to snorkellers, so you can get very close to these impressive large rays.  

THE GUITARFISHES (Family Rhinobatidae)

The guitarfishes are the largest family of shovelnose rays, with 31 recognised species. These rays are small to medium sized, with most under 1m long and the largest species growing to 1.7m. Members of this family are found in tropical to warm temperate waters across the globe. Guitarfish are similar in appearance to giant guitarfish, having a translucent snout. But they have smaller dorsal fins and differ on a molecular level. Many members of this family are a plain brown colour, but others are covered in a pattern of pretty spots, rings or blotches. Only one member of this family is found in Australian waters, the very rare Goldeneye Guitarfish (Rhinobatos sainsburyi). Only found off northern Western Australia, in depths between 70m and 200m, I don’t like my chances of ever encountering this ray.

IMAGE BELOW - EASTERN SHOVELNOSE RAY (photo by Nigel Marsh)

THE BANJO RAYS (Family Trygonorrhinidae)

Many of the banjo rays look very similar to the guitarfishes, and until recently they were all grouped together in the same family. However, they differ at the molecular level, so the eight members of this family have been separated from the rest. Five members of this family are only found in Australian waters, with the other three found off Central and South America. Banjo rays are medium sized rays, with most growing over 1m in length. Most of these rays have a round-shaped head, hence the name, and all have a pattern of bands or blotches across their head and body.

The Eastern Shovelnose Ray (Aptychotrema rostrata) is found from southern New South Wales through to central Queensland. This sandy coloured ray has darker blotches on its body and grows to 1.2m long. Found on sandy bottoms and reefs, the species is mostly found in shallow water, but has been recorded to 220m. The Eastern Shovelnose Ray is one for those rays that you stumble across every now and then. I have seen the occasional one in Jervis Bay, Port Stephens, Bundaberg and off Brisbane. However, the only reliable place I have seen them is at Mudjimba Island, off the Sunshine Coast. The sandy bottom around this island must be the perfect habitat for this species, as on most dives I see one or two. I have also seen pregnant females here in late spring, a time when they give birth to four to 18 pups. Eastern Shovelnose Rays often hide under a layer of sand by day, and with complete confidence in their camouflage they generally allow divers to inspect them very closely.

IMAGE BELOW - WESTERN SHOVELNOSE RAY (photo by J. Martin Crossley)

The Western Shovelnose Ray (Aptychotrema vincentiana) looks very similar to its eastern cousin, but is smaller in size, growing to 84cm in length. Although found over a much larger area, from Victoria to central Western Australia, this species is much rarer than its cousin and only occasionally seen by divers. I have spent many dives looking for this elusive ray, and when I finally found one off Freemantle it disappeared in the surgy conditions before I could get a good look or a photo!

The best-known members of this family are the fiddler rays. The Southern Fiddler Ray (Trygonorrhina dumerilii) grows to 1.4m and has a pretty banded pattern across its round head. This species is found from southern Western Australia to Victoria, and is found on rocky reefs, sandy bottoms and amongst seagrass and kelp. Divers see this species infrequently at dive sies off Perth and Adelaide. I have always found the best place to see one is around the many piers that stretch into Port Phillip Bay, south of Melbourne. This species is very placid and very tolerate of divers closely inspecting it.

IMAGE BELOW - SOUTHERN FIDDLER RAY (photo by Nigel Marsh)

The Eastern Shovelnose Ray (Trygonorrhina fasciata) is a far more abundant species found from southern New South Wales to southern Queensland. This species also typically has a much bolder pattern across its head and grows to 1.2m in length. This pretty ray can turn up just about anywhere across its range, but I have always found them to be most common south of Sydney, especially in Jervis Bay and at Montague Island. The Eastern Fiddler Ray often hides under a layer of sand, but I have also found them hiding under rocky ledges and amongst the kelp. They are an easy ray to approach and photograph, and sometimes you can find dozens at a single spot, often lying side by side.

IMAGE BELOW - EASTERN FIDDLER RAY (photo by Nigel Marsh)

SHOVELNOSES UNDER THREAT

With shovelnose rays having shark-like bodies, they have found themselves targeted by fishers in many parts of the world for their fins. This hideous practise of taking their fins to supply the shark-fin soup market has seen populations of these rays decimated throughout Asia, with some species seeing an 80% reduction in number. Many species are listed as vulnerable or critically endangered, and with their slow growth rate and low reproduction rates it is feared that many will become extinct unless overfishing is stopped.

Fortunately for us, the Australian populations are healthy, and fisheries only have a minor impact on numbers, meaning that divers will have many more wonderful encounters with the shovelnose rays for many years to come.