Sawfish are very unique creatures, which sometimes poses problems when working with them. The saw of a large sawfish can easily be one the biggest safety hazard you will face during fieldwork. But these animals have another adaptation that has made it difficult to attach tags to them. As the animals often come into shallow waters they have the ability to loosen up their dorsal fins, allowing the fins to fall on the side.
When I worked with captive largetooth sawfish (locally in Australia known as freshwater sawfish) Pristis pristisa decade ago, I realized that in situations that I interpreted as likely stressful for the animals, their two dorsal fins would not stay upright anymore. In captivity these situations included water changes where the water levels in the tanks were first dropped and again raised.
In the wild, when juvenile sawfish venture into shallow waters of 20 cm depth or less, they could easily fall prey to terrestrial predators such as wedgetail eagles, which can reach a wingspan of 2.8m and are commonly encountered in the outback, and near rivers in Northern Australia. This means that it might not be stress, but the low water levels that caused the fins to drop!
The floppy fins pose some difficulties to attaching satellite tags to the dorsal fins of sawfish. The last time that sawfish in Australia, according to our knowledge, were tagged with satellite tags was in 2008 (Stevens et al. 2008). The authors tagged 7 sawfish (5 P. clavataand 2 P. zijsron) with SPOT tags that were bolted to the tip of the dorsal fins of sawfish. These tags are commonly used on sharks, and they can only connect to a satellite and send a location point when the dorsal fin breaks the surface. Additionally one pop-up satellite archival tag was put on another P. clavata. While the PAT tag provided depth data and popped off from the animal after 49 days within a few km of the tagging location, the SPOT tags only provided a handful of locations each (Stevens et al. 2008).
Dr Wueringer holds a towed SPOT-253 tag from Wildlife computers that has been attached to a sawfish. Note the first dorsal fin of the animal falling to the side.
The dwarf sawfish that has been tagged is ready to be released.
Since then, satellite tagging of sawfish has come a long way, and thankfully with the information provided by our American colleagues, our tagging has been more successful. They successfully trialled the methods of attaching towed tags to large smalltooth sawfish Pristis pectinata (for more info see Carlson et al. 2014, Guttridge et al. 2015, Papastamatiou et al. 2015) and shared their set up with us.
The next challenge for us was to find sawfish that were healthy (i.e. did not have their saws amputated) and large enough to tow the tags. In March 2019 it finally all came together and we were able to deploy two of our towed SPOT (smart position and temperature) tags! The first one was deployed on a 280cm long, and likely sexually mature female, Dwarf sawfish Pristis clavata and within 24 hrs the second tag was deployed on a 300cm long juvenile green sawfish Pristis zijsron.
One tag detached after about 3 months while the other one stopped sending location data 10 months after deployment. However, while the analysis and project is still ongoing, we can already see that the data we have received is amazing.
One of the most important outcomes of the tag deployments is that we were working with a commercial fisher on this expedition, who now knows how to deploy tags for us and is excited to do so. So we hope that the next tags won’t have to wait another 3 years to be deployed, as we all work together to find large sawfish.
This image shows a subset of the raw location fixes that we received from our tagged green sawfish. Each dot represents a location fix. Location fixes can have errors (including land based locations), especially when a tag does not surface long enough to send its data to the satellite.
This blog post was originally written for the Save Our Seas Foundation. you can access the original here.
References
Carlson, J. K., Gulak, S. J. B., Simpfendorfer, C. A., Grubbs, R. D., Romine, J. G. and Burgess, G. H. (2014). Movement patterns and habitat use of smalltooth sawfish,Pristis pectinata, determined using pop-up satellite archival tags. Aquatic Conserv. Mar. Freshw. Ecosyst.24, 104-117.
Guttridge, T. L., Gulak, S. J., Franks, B. R., Carlson, J. K., Gruber, S. H., Gledhill, K. S., Bond, M. E., Johnson, G. and Grubbs, R. D. (2015). Occurrence and habitat use of the critically endangered smalltooth sawfish Pristis pectinata in the Bahamas. J Fish Biol87, 1322-1341.
Papastamatiou, Y. P., Dean Grubbs, R., Imhoff, J. L., Gulak, S. J. B., Carlson, J. K. and Burgess, G. H. (2015). A subtropical embayment serves as essential habitat for sub-adults and adults of the critically endangered smalltooth sawfish. Global Ecology and Conservation3, 764-775.
Stevens, J. D., McAuley, R. B., Simpfendorfer, C. A. and Pillans, R. D. (2008). Spatial distribution and habitat utilisation of sawfish (Pristis spp) in relation to fishing in northern Australia. 26.
Since 2015, Sharks And Rays Australia is working with sawfish in Queensland. They are globally critically endangered. We spend about 3 months in the field every year, sampling for these animals in some of the most remote sites in Australia. On every field trip we visit a remote school, and when possible we work with the local Indigenous Land and Sea Rangers to increase their knowledge on sawfish and how to look after these animals. We also work with commercial fishermen to create a sustainable model of conservation that also maintains healthy fisheries.
In July 2019, we had a car accident on our way to our field site. Luckily nobody was injured but our amazing expedition vehicle, a Landcruiser Troopcarrier, was destroyed. While the insurance has paid out what they consider the market value to be, it does not even cover half of the cost of a replacement car, let alone fitting out the car to be field ready.
Please help us! Anything counts towards our goal – so remember, no donation is too small!
If you are a sawfish hero or business, from a donation of A$ 750 onwards we will add your sticker on the back of our expedition vehicle, for all of remote Queensland to see. For donations above A$ 3000 you will be allowed to name one of our satellite tagged sawfish and receive a certificate and 3 updates on its whereabouts. For donations of or above A$ 5000 you will be mentioned as a sponsor on our homepage for 2020! If you are representing a business please contact Barbara@saw.fishto check that our values align.
Thanks so much everybody, together we can make a difference!
In Australia, we have a responsibility to look after our four species of sawfish. Sawfish are the most endangered of all sharks and rays globally. Northern Australia is the last global stronghold for four out of five species.
For this year’s International Sawfish Day, some major media outlets became interested in Australian sawfish. These animals are receiving a lot of media attention recently, and with this comes a network of opinions and agendas. Because of these two recent articles on ABC and in the Guardian Australia, which present and also intermingle a lot of different view points, I would like to elucidate the direction of Sharks And Rays Australia in this field.
For the last 5 years, under my lead, SARA has worked with sawfish in Far North Queensland, the Gulf of Carpentaria and the Cape York Peninsula. Our philosophy for sawfish research and conservation is that ‘it takes more than a village’ to bring sawfish numbers back and we need everyone involved. Now, if you are one of the fishers who say that you still see plenty of them, I might ask you to take a look at our species ID flyer. Right now, we are mainly concerned with the three Pristis species, which take 8-10 years to become sexually mature. Anoxypristis (narrow sawfish, slimy’s) mature after 3 years and are thus still found in higher numbers. But even Anoxypristis is in trouble. In 2016 we found fins from this species on a drying rack in the Gulf of Carpentaria, and in 2018 we had a sighting of a sawless individual from the east coast submitted to us. If you regularly see large numbers of the other species, please report them to us!
In Australia, sawfish are federally protected on the EPBC Act and in Queensland they are also protected under the Fisheries Act, which means that from a legislative perspective, they are well covered. But once you spend time in remote regions, talking and working with station managers, Indigenous Rangers and fishermen, a whole different picture emerges. Everyone has a story to tell, of how they used to catch ‘really big ones’, but haven’t seen a single animal in 10-15 years. And everyone has someone else to blame for this.
The reality is that every single person who took a sawfish saw as a trophy contributed to the species’ declines. But while pointing the finger only creates scapegoats, anger and an outlet, it does not help sawfish. These animals continue to fall through the cracks. Instead of judging the past it is more helpful to take responsibility and change the future.
And in this, everyone has a role to play:
Our regular visits to schools have led to the collaborative development of materials. The Normanton State School has taken the life cycle up in its curriculum, and last time we visited they baked a sawfish shaped cake. Love your work!
We also work with commercial fishers. So far, I have only collaborated with a handful of fishers, but these guys are now putting tags on sawfish for us and releasing them alive. They are happy to go out of their way to release a 4m sawfish, even when working by themselves. Needless to say, this can be very dangerous as sawfish use their saw to defend themselves and such a large animal can hurt people.
We are always on the hunt for sawfish sighting submissions from the general public and recreational fishers. The old records that you have at home are important for sawfish conservation. We do not judge people who are in the possession of old saws, it is pretty clear that everyone used to take them as trophies. But it is important that this practise stops, as most animals will not survive this illegal procedure and their saw is much more important then as a dust collector. Your sawfish sighting submissions have already allowed us to show that the historic range of freshwater sawfish was larger than previously assumed, as they occurred near Brisbane.
Our field assistants are not shy to join us on our field trips and do the hard work. Working in remote regions, without the daily pleasantries of hot showers, air condition and high speed internet, and contributing financially to make those expeditions happen, these young adults are my heros. They might disappear back into a different world after the expedition, but they now understand what’s at stake.
We also work with Indigenous Land and Sea Ranger groups. With every group we have different agreements, and some are more hands-on in helping us than others. But all of them matter, and sawfish matter to them, as you can see in this blog post.
We also work with the public aquarium industry, who have sponsored some of our tags and are spreading the word for sawfish through their educational displays.
What about net free zones? Shall we close down all gill net fisheries? I personally think that net-free zones are only a solution in close vicinity of towns with large recreational fishing communities, and active fisheries enforcement. Closing down fisheries is not a solution, as it only exports the problem. Gill nets are used everywhere around the world, and in Australia we can document and invent methods of making these fisheries sustainable when it comes to sawfish by-catch.
In the remote areas that we work in, the displacement of fishers would mean that huge stretches of coastline will receive minimal attention in terms of patrolling and enforcement. The coastline of the Queensland Gulf of Carpentaria alone is about 1200 km long. This could create an open field for foreign fishing vessels, with no quotas or indications of catch and by-catch sizes or management strategies.
The area we work in covers about 2/3 the size of Germany, but it is only inhabited by 28,000 people. Germany, on the other hand, is inhabited by over 82 million people. In such remote areas, it is easy for foreign vessels to enter Australian waters undetected. Remember the vessel full of illegal immigrants that arrived in the Daintree, north of Cairns? This vessel crossed at least 800 km of Australian waters undetected before reaching the coastline.
The Australian fishermen and fisherwomen that I have met have an understanding of how their work changes the environment they work in. They are protective of their industry, that’s for sure, but they are also willing to adopt release practises that are safe and cause minimal harm to the animals. Many of them have developed great methods to release sawfish unharmed, and one of our ongoing projects is to document these methods, with the aim of making them available to every fisher. Without their help, the task of collecting data on Queensland’s sawfish populations is almost impossible. However, individuals who kill sawfish, like the recent deaths in Wujunga or this fisher, who was later found in possession of 63 illegal saws, can give a whole fishery a bad name.
My paper on the sawfish by-catches in the Queensland Shark Control Program indicates that sawfish survive the initial capture in a gill net. Anybody who has caught sawfish in this way, including myself, can confirm that as long as the animals’ gills are not wrapped up they can survive the capture. The key threatening process for sawfish is thus not the capture but the release. It is imperative for the survival of these species, that the animals are released alive, quickly and with minimal damage. Many fishers have adopted methods to avoid catching sawfish (like avoiding certain areas in the ecosystems they work in, or checking their nets very often), and many of them are aware of environmental conditions that will increase sawfish captures. These factors need to be documented in order to create best practise standards across fisheries. Ultimately, I would like to see a Sawfish Sustainability Certification for our Australian fisheries that interact with these animals, but this would require large-scale collaborations between governmental agencies, the conservation sector and fisheries.
Please think about how you fit into sawfish conservation and what you can do to protect these animals, instead of pointing the finger at other people. For example, if you live in an Australian city, you could become a sawfish ambassador and visit schools, hold outreach events and bring the memories of these animals back into people’s minds. This is hard work, but it is also more effective than signing a petition or liking a sawfish conservation post. You could also crochet us a sawfish to give to a remote school, or you could join us in the field. We need more sawfish heros.
Once a year, the Cairns Indigenous Art Fair kicks off in Cairns. Indigenous artists from all over Far North Queensland and Cape York come to Cairns to display their arts. The event grows bigger every year and features so many works on sharks and rays that we always try to be in Cairns for CIAF.
This year, Julia, who is our instagram wizard, and myself visited CIAF together. We grabbed some food and sat down in the grass to listen to what was going on at the stage. Various Indigenous leaders from the Cape were talking about how their language and culture was slowly being lost. At some point, one of the elders started to talk about sawfish. He said that they had disappeared from his native waters and that he was from the community of Pormpuraaw. I looked at Julia and said, ‘We need to talk to him!’
After the session we introduced ourselves to Syd Bruce Shortjoe. I told him that we work with sawfish and that we would like to help him protect these animals in the waters of Pormpuraaw. I told him that SARA already works with the Mapoon Land and Sea Rangers as well as the Kowanyama Land and Sea Rangers. As I had heard of recent captures of sawfish from the Pormpuraaw region, I said to him that sawfish still exist in his native waters, but probably in very low numbers. I also gave Syd one of our flyers and a sunnies neoprene strap that has all the information on how people can submit sawfish sightings to us. While Syd was listening, he started stroking the sawfish image on the neoprene strap.
Syd told us that his great grandfathers’ totem is the sawfish. He said that because of this, the sawfish is part of his family and his culture. If the animals go extinct, then not only is the species missing from local ecosystems, but it also means that the totem goes extinct. In his cultural belief, you become your totem animal after your death. His grandfather’s totem is the green sawfish, and Syd described the animals very accurately. In Mugu, the sawfish is called kapainyinh.
Syd is the first person who I have met who had a sawfish totem in his family.
He looked at me and grabbed my arm. He said ‘Sawfish cannot disappear. This means my family’s totem disappears and my culture disappears. And with your help we can stop that.’ I grabbed hold of his arm and said to him that I will help him and I will try my best to teach his community, his people, the school kids and the rangers so that we can all come together to look after sawfish and bring these animals back to his waters.
This moment was highly emotional for Julia and myself. While we often meet people who are very interested in sawfish, and while we both understood the cultural importance of sawfish to Indigenous Australians, we were completely unaware of the cultural impacts of the species’ declines.
When Syd looked at me and asked me for my help I realized that there is too much at stake. We need to look after sawfish and we need to do this together.
At the Cairns Indigenous Art Fair. From left to right Barbara Wueringer (SARA), Eliot Koonutta (Pormpuraaw artist), Julia Constance (SARA) and Syd Bruce Shortjoe (Pormpuraaw Elder)
This blog post was written for the Save Our Seas Foundation. Access the original here.
By Paddy Burke (Sharks4Kids ambassador & PhD student at Macquarie University, @Patrick_Burke)
The ocean is filled with so many incredible creatures, incredible and bizarre. Many of these fish have evolved under similar pressures which have led them to look quite similar even if they are genetically quite distinct. This similarity in appearance or development of similar structures is what is known as homology. One great example for this can be seen in sawfish and sawsharks!
Now many of you may be saying, wait, aren’t those the same thing? The answer is no! While these two groups of fish are very similar in appearance, they actually have quite a few big differences that can make it easy to tell them apart once you know them! The differences we will cover today are their ‘saws’, general body size and the gills.
The ‘saws’ or elongated toothed rostra are the features that make these fish really quite unique. The saw is thought to be used for predation and defense in both groups. However, the actual structure of the saw is really quite different! Sawfish saws are lined with a number of teeth along both sides of their saw that vary in size and number by species but each one of these teeth are permanent! Meaning that if they happen to lose one it will never grow back. The rostral teeth of sawfish also grow from their base, like a rodent’s tooth, so that the animals can sharpen them regularly in the sand. Sawsharks on the other hand have a very different saw. Teeth can be found along both sides of the saw like in sawfish, however, sawshark teeth are replaceable! The most distinguishable feature to separate a sawfish and a sawshark saw is the presence of what are called ‘barbels’. Barbels are found only on sawshark saws and they look like a little moustache coming off the saw. This moustache is thought to have a tactile function, meaning they use them to feel around in the sand for food.
The size of fish is an easy indicator of species between these groups. Sawfish are very large fish, some reaching over 7 meters in length! While sawsharks are much smaller, averaging around 1 meter for an adult depending on species. In addition to size, it is important to know that sawfish are technically rays while sawsharks are true sharks. What that means is that in sawfish you will find their gills located on the underside of the fish. Where as in sharks they are located on the side of the head.
These fish could be considered ‘cousins’ in a way since they are both chondrichthyans, meaning they both have a skeleton made out of cartilage instead of bone. However, it is important to remember that sawfish are actually rays while sawsharks are true sharks. Sawfish may not follow the typical body plan of their relatives the stingrays, but they are more closely related to them than they are to sawsharks!
A sawshark, Pristiophorus nudipinnis resting on the substrate. See the barbels? Image by Tristan Guttridge.
A freshwater sawfish, Pristis pristis, is disentangled from a gill net in order to be tagged and released. Its teeth are evenly sized and spaced, contrary to those of sawsharks. Image by Dave Nash.
