22 minute read
WHAT LIES BENEATH
WHAT IF WE CAN HAVE THE BEST OF BOTH WORLDS – BRILLIANT TROUT FISHING IN THE MOUNTAINS OF THE WESTERN CAPE AND NEW (YET ANCIENT) FISHERIES FOR LARGE INDIGENOUS SPECIES THAT READILY TAKE A FLY? IF GAME-CHANGING CONSERVATION BIOLOGIST DR JEREMY SHELTON’S VISION FOR THE FUTURE IS ACCURATE, THAT WILL BE THE REALITY IF STAKEHOLDERS LIKE US DO OUR BIT.
Photos. Jeremy Shelton, Steve Benjamin, William Lotter, Leonard Flemming, Nicholas Hampton
I’m embarrassed to admit that, until about five or six years ago, I wasn’t really familiar with the large, indigenous freshwater species that existed in my own back yard here in the Western Cape of
South Africa. I knew about Clanwilliam yellowfish, but sawfin, witvis and sandfish weren’t really anywhere on my radar. I knew nothing about which river systems they occupied and I was oblivious to how threatened they are.
Now I know a lot more about these fish. That’s in part thanks to the fishing friends I hang out with, but largely thanks to the work people like Jeremy Shelton do. A freshwater conservation biologist and visual storyteller, perhaps you know Jeremy as one of the brains behind initiatives like the Saving Sandfish project. Maybe you’ve come across him deep in the mountains snorkelling the streams and conducting experiments on the fish they hold. Or it could be that you’ve thrown your bra or jocks at him when he was noodling out a crazy beat on the Djembe drums and shakers front stage at a West Coast Wolves concert. Whatever the case, we’re fans of his work because, not only is Jeremy educating people like me, but he’s taking the conversation around freshwater conservation beyond just protecting and conserving these ecosystems. He’s promoting a different future for them altogether. I remember meeting Jeremy at the Cape Piscatorial Society (CPS) AGM a few years back when he, and a couple of colleagues from Cape Nature attended what are usually necessary, yet mind-numbingly boring, procedural affairs. To provide some context – the CPS is one of the biggest and oldest fly-fishing clubs in South Africa and it manages the trout streams of the Western Cape for members. To do this, the CPS works with Cape Nature (the regional nature conservation/parks management association in the Western Cape).
When Jeremy and his mates arrived at that AGM, a harrumphing chorus of negative old man energy ran through the room. The tension was as palpable as a bad drift on a clear glide. Why? Well, I discovered later that some members of the society assumed that, by the very nature of their work with Cape Nature and their efforts with indigenous fish, Jeremy and co. must therefore be rabid members of the anti-trout lobby. To be fair, that mistrust was somewhat understandable given that over the years there have been occasional anti-trout zealots in Cape Nature who have rattled their sabres at the flyfishing community, threatening to eradicate our beloved salmonids by poisoning rivers with rotenone. Never mind that it was Cape Nature who originally stocked the rivers with trout over a hundred years ago.
The thing is, that animosity was misplaced, because Jeremy Shelton unashamedly loves trout. Considering he is one of the foremost protectors and fans of ‘fynbos fish’ (a neat descriptor for the endemic indigenous species that live in the streams and rivers of the Cape mountains), that may come as a surprise to some, but Shelton has spent a large proportion of his life properly nerding out on trout.
As a teen he spent every waking minute catching carp and bass and then his attention turned to trout, and in 1996 he joined the CPS, the very organisation where 20odd years later at that AGM he was getting some mild stink-eye. In matric his biology project was on trout and in his tertiary studies they would continue to play a central role. After graduating from university with an Honours degree in zoology, Jeremy went travelling, spending some time in Canada visiting his father and fly fishing for salmon, surfing in Indonesia and generally doing that mid-twenties ‘find yourself’ thing. But then he returned to academia and trout.
“After travelling I had lost my interest in studying and in science. A friend of mine had, without me knowing, enrolled me in the conservation biology Masters programme at
Clanwilliam Redfin Minnows
Cape Kurper the University of Cape Town which, he thought, was the best thing ever. He put in an application for me and I was accepted before I even knew I’d applied. I was pretty pissed off initially but, about a month or two into the course, I realised that this was the best thing ever. This was because it was this shift from dry science into conservation biology which is a much broader field that included everything from teaching to communication to communities. That was the start of my real love for conservation.” After his Masters, Jeremy did his PhD research on rainbow trout in the Cape. The further he investigated the streams and river systems, the more he discovered about the impact his beloved trout and other aliens (like bass) have on the indigenous ‘fynbos fish’ that were there in the first place. Jeremy says, “I often get asked the question, ‘What’s the most important part of deciding to do a PhD?’ For me it was all about being passionate about the subject. I did a lot of reading about what happened when trout were introduced in other parts of the world like New Zealand, Australia, South America and other places where certain species of trout may not have been indigenous. There were some really interesting patterns, some of which were consistent across these different continents. To try and understand what was the relationship with trout and river eco-systems here in South Africa. I ended up designing a study that involved a blend of field surveys, but also some experimental work. The idea behind the field surveys is actually a very simple one. We were lucky enough to have this natural experiment here in the Cape where we’ve got a whole lot of rivers where trout have established and then a bunch of other, very similar rivers without trout. Often it’s just a waterfall that’s stopped them from getting in, or they just haven’t been stocked there. So, it was a really good opportunity to do this comparative study to see how the river ecosystem with trout, differed from that without trout.
“What we found was that, in the cases where trout really thrived, in the ecosystems that were ideal for them, it looked like they were probably displacing the indigenous fish. Because the trout and the indigenous fish feed on different things, that had some knock-on effects for the insects and even the algae in those food webs. In the places where trout did less well, you’d often find them co-existing with the indigenous fish and there the effects on the river food web were a lot more subtle. There are limitations with every approach and with a comparative study it’s very hard to tease out what the cause and effect of those patterns is. It’s more just about observing a relationship. That’s where the experimental component came in. We put some cages in rivers, some with trout, some with indigenous fish to try and really understand how these two different kinds of top predators would influence the food webs around them.”
Sawfin from a Cederberg river
As he spoke to me about his PhD it became glaringly apparent that while Jeremy acknowledges the impact of trout on an eco-system in the streams where they have established themselves, he’s also aware there’s not much point in trying to do something about it now. As with the introduction of trout in places like New Zealand or Argentina, it’s a case of that horse (or that fish) has bolted. Regardless, there are bigger threats.
He says, “I have always loved and respected trout. I still love fishing for them. It took me a long time to understand how something that seems to be thriving in these rivers and bringing a lot of joy to fishermen could also be potentially doing some ecological harm. I think that’s partly why I needed to go and really try and do the best research study I possibly could to get to the bottom of this and really understand what was happening underwater.
“In South Africa we’ve got a wide range of non-indigenous fish introduced from around the world either for fishing or as forage for those angling species. There’s definitely a varying degree of impact that these species will have on river ecosystems. Bass – smallmouth, largemouth, spotted etc – they are probably the most voracious. It’s very unusual to find situations where indigenous fish are still able to co-occur and co-exist with bass. Their predatory impacts are just so strong. With a species like trout, their impact is a bit more subtle and there are a lot of cases where they are able to co-exist with indigenous species. Their diet is a bit different to bass. Bass are really piscivorous whereas trout have a wider dietary range and will feed a lot more on insects. In many cases, particularly in areas where the conditions of the river might be a little bit marginal for the trout – that’s where you see the coexistence with indigenous species – and I think there’s a bit more of a natural balance in a lot of the places where trout have established themselves.
“One way to think about it is that trout need cold, clear water whereas some of the other invasive species like bass, carp and sharp-toothed catfish, are less concerned about the temperature or condition of the water. They’re able to spread pretty much throughout river systems until a big waterfall or something stops them. Generally, trout are confined to the cooler headwaters where they’ve been stocked. It’s not as easy for them to spread through entire river systems.”
What about the perceptions of tension and conflict between the scientists and anglers like me, with Gollumlevel anxiety that our “precious” will be taken away? Put down the pitchforks and breathe easy. For Jeremy, the eradication of trout is not something he sees as remotely achievable or even desirable in most cases.
“I think there’s been a long history of scientists and anglers in this part of the world having quite energetic conversations around the place of trout in our rivers here in the Cape. The way I see it (and most scientists that I speak to today see it the same way), is that trout have a very important place in our riverscapes. They bring in a lot of eco-tourism value to the area and a lot of enjoyment for fly fishermen like myself. I think it’s completely unrealistic to think that there’s going to be this widespread removal of trout from rivers in the Cape… ever. The only time where trout removal from a section of river could, or should, be considered, is in a very specific situation where there will be a clear benefit for a very threatened indigenous species or a very threatened indigenous ecosystem. That needs to be a very well thought out project. Even if we wanted to remove an invasive fish from an entire long length of river, there’s just not the capacity to do it. In terms of those historic trout fisheries in this part of the world – the Witte, the Molenaars, the Holsloot, the Elandspad – there’s just no need. There’s a balance that’s been established there, they clearly have a lot of value recreationally and there’s no low-hanging fruit that by removing trout you directly benefit a threatened species.” At a time when so many issues are seen as binary – you’re either with us or against us; right or wrong ;the indigenous fish lobby vs the trout fans – there is something incredibly refreshing and realistic about his take on the status of trout in South Africa. Jeremy’s practical mindset goes even further when it comes to you, dear reader because, as a scientist and conservationist (and also as a fellow angler), Jeremy sees the fly-fishing community as part of the solution instead of seeing us as vocal opponents. To him, we’re citizen scientists and, by virtue of the places we fish, we’re camo-clad canaries in the coal mine.
He says, “Fly fishermen are probably the people who spend more time out on our rivers than anybody else and are, in many cases, the most knowledgeable, the most intouch, the most intuitive and the most passionate about our rivers. A lot of what I’ve learnt about fish and river food rhythms has been from fishermen, asking questions and spending time with people on the rivers. The fishermen are a really important part of the freshwater community and the conservation of our river eco-systems, particularly the future of our healthy rivers in the Cape. I have a lot of respect for fishermen, particularly the fly fishermen who are up in the headwater streams which is where a lot of the healthy river ecosystems are still intact.” Bringing in different stakeholders, understanding who needs what and why and finding positive, pro-active solutions is an approach that goes beyond what you usually expect from scientists. Marrying data with communication is something you’d expect from a community leader or activist. It’s something that Jeremy attributes to an epiphany he had after years of hard work resulted in little change. “After my PhD, I’d really been trained as an academic, a scientist, someone whose job is to go out and collect data, analyse data and to try and further our understanding of how eco-systems are changing. I kept on working in that field for a few years and started becoming aware of the levels of threat to our freshwater species and ecosystems. No matter how many scientific papers were being published, the precarious state of freshwater here was just getting worse. It no longer felt right for me to just keep on doing science. That’s when I really dove-tailed my focus into a conservation space. Science is all about data points and species, and conservation is all about people and understanding people’s relationship with ecosystems. My work has shifted from being someone who spent a lot of time dipping electronic instruments into rivers to try and measure them, to now spending a lot more time talking and listening to landowners and all sorts of different stakeholders to try to find a better water balance for people and nature.”
A great example of how working with landowners and listening to stakeholders can pay off, is the work Jeremy and his colleague Otto Whitehead have been doing with the Saving Sandfish project. “In South Africa, we’ve got just over a hundred species of indigenous freshwater fish and then around about 30 or 40 introduced species as well. Here in the Western Cape, we’ve currently got 23 recognised indigenous species, but this is a number that is constantly being revised. Twenty three is not a high number but, what is quite special about the species here is a very high level of endemicity. Those are the species that are unique to the region and aren’t found anywhere else. I think it’s about 70 or 80 percent that are unique to the fynbos. I like to call them our fynbos fish. Along with that high level of endemism, there’s also a very similarly high level of threat. Most of those endemics are considered threatened by the International Conservation Union. This part of the world is a real hotspot for freshwater fish conservation.” Of those 23 species Jeremy mentions, most are really tiny fish, but there are several larger species, mostly in the family cyprinadae, the same family that carp belong to. That’s the Clanwilliam yellowfish, the sawfin, the witvis or whitefish and also the Clanwilliam sandfish. These are species that will grow really big in the case of the Clanwilliam yellowfish, but they are also some of the species that have taken the hardest knock over the last century. The most threatened of the lot, of any migratory freshwater fish in South Africa, is the sandfish.
Jeremy says, “The Clanwilliam sandfish is listed as endangered by the IUCN (International Union for Conservation of Nature), which is the second most serious threat category. So, it’s not in good shape. When I say migratory, it’s got this life cycle where it needs to do quite large-scale migrations to complete the cycle. Most fish species migrate on smaller scales. Even the little redfins, when they spawn, migrate from a pool, up into a riffle to lay their eggs and then back into the pool for winter. With the sandfish, it’s tens (and sometimes even possibly hundreds of kilometres) to move from the pools where they spend the dry summer in the Doring River, up into the tributaries where they love to spawn. I think it’s that migratory life history that makes them incredible ambassadors and barometers of healthy and connected free-flowing rivers, but it also makes them really vulnerable to impacts like dams, particularly the over-abstraction of water, disconnecting their habitats.” The area where the sandfish are found, in the Doring River, is a very dry part of South Africa that sits slap-bang between two global biodiversity hotspots – the Cape floristic region, which is the fynbos area, and then the succulent Karoo, stretching out into the Tankwa. It’s an area where water is becoming more and more scarce for both fish and farmers. Jeremy says, “The river systems in that part of the world are very extreme in terms of their flow and their temperatures so, for a lot of the year, these systems aren’t flowing at all. During the heat of summer, the fish are restricted to just a few isolated pools where they are just in survival mode, waiting for the next winter rains. Right now, we’re having really good rains and that starts to connect those fragmented rivers. Once we start transitioning from winter into spring time, the flows start subsiding a little bit, the temperatures start increasing, all the flowers pop out, and that seems to be what triggers the spawning migration of the sandfish. They will move from those pools, in groups, into their preferred spawning areas higher up in other tributaries. So, it’s an animal that is very closely tied to these environmental triggers of temperature and flow. These fish have lived in these extreme environments for a long long time and they have got this behavioural memory of how to cope with extreme fluctuations of inflow and in water availability. But, I think, like every living organism, there’s a tipping point or threshold up to which they can still persist. I suspect that with some of these larger fish species, we may be getting quite close to that limit, which is quite concerning from a conservation standpoint.” Just how attuned the migratory indigenous fish species of the Cape are to their environments was rammed home when Jeremy explained to me how Clanwilliam yellowfish respond to similar behavioural triggers to the Clanwilliam sandfish. They only appear to spawn when they know that their eggs and little larvae have a good chance of surviving. Scientists are still trying to figure out how they know that.
“A colleague of mine Bruce Paxton did his PhD on the spawning biology of the yellowfish and the sawfin in the central Cederberg around the Sanddrif / Driehoek area. He was following their spawning behaviour for a few years and throughout his project he found that the sawfin, which are a bit of a smaller, possibly less particular species, were spawning every year. But the yellowfish didn’t spawn at all during his two or three year study. Bruce said he didn’t really know how they know when to spawn but, probably, like most things in nature, it’s a combination of reasons that has something to do with the flow and temperature. He said they have this incredible ability to know when the last cold front of the winter comes through – and that’s when they love to spawn on the tail-end of that front. That would make perfect sense because if they spawn and another big cold front comes through, it will wash away all their eggs and their recruitment is going to take a big hit.” To save the sandfish, Jeremy and his colleagues are doing everything they can to better understand what makes them tick. From the life cycle of the sandfish, to the habitats they need for their different life stages – spawning, egg laying, juvenile development – but also identifying what the biggest threats to them are.
“We’ve spent a lot of time looking at the sandfish situation to figure out what can be done to increase their numbers. There’s a situation at the moment where these fish from the Doring, move up in spring time in very small numbers into a small number of tributaries. They are capable of laying lots of eggs, maybe ten thousand per individual. By late spring, those rivers are teeming with tiny little sandfish but, the scary thing is that, by December, in two or three months’ time, they pretty much all die. That’s because most of them find themselves trapped in little pools along with bluegill, an invasive fish introduced from North America. But more than that, they actually run out of water in some of these tributaries that used to flow throughout the year. The reason for the lower flows today compared with 500 or 100 years ago is complex. Climate change impacts; the spread of thirsty invasive trees like prosopis (mesquite) and agricultural needs. By removing alien fish from farm dams, the Saving Sandfish project is attempting to recreate these permanent bodies of water in some of these tributary catchments that probably would have been there a hundred years ago. We’re working with some really cool and interested landowners to take the carp, the bluegill, the bass out of those farm dams and recreate these safe environments that the sandfish have lost in the wild. We simply go and collect as many small sandfish as possible while they are still in the river before they get eaten by the bluegill or they run out of water. We put them in the farm dams and the idea then is that they have safe space to grow to a safe size. Once they are big enough, we will release them back into the wild and hopefully they will be able to contribute to the spawning population and an increase in numbers of the species.” “There’s been a shift in mindset around land use and that’s been a great thing for freshwater conservation. People want to get out of the cities and spend time surrounded by nature, spend time surrounded by beautiful unique species that this part of the world is so well known for. We see a lot of the farms that were once fully operational livestock farms, transforming into guest houses and guest farms. We have a lot more landowners that are really keen to have one of these sandfish sanctuaries on their farms, to tell guests about it and to play a role in this bigger conservation initiative. I’m hoping that some of these farm dams will become places where people can go fly fishing for indigenous species. If we don’t care about these species, then we’re not going to look after them and they need some serious looking after. Increasing the opportunities for local indigenous fish fly fishing is not a luxury, it’s critical to achieving conservation success.
Just imagine for a moment, as a fly angler in the Western Cape, if along with the brown and rainbow trout we already have in specific well-known streams, you could also pick from four or five viable indigenous species in our local rivers? Perhaps one sunny Saturday, you’d like to book a beat on the Hex river for witvis which get to a hefty size and love dry flies. You could take a long weekend in the Cederberg to target sawfin on hotspot nymphs or head to the Tankwa Karoo to try get the Holy of Holies, a massive Clanwilliam yellow (the all-tackle record currently stands at 22.5lb). Maybe you want to try micro-nymphing for sandfish in the Biedouw river valley, where, if you get the timing right, you might catch and release one of the rarest fish in Africa, while experiencing the trippy natural phenomenon of the wild flowers transforming the desert from shades of brown into a kaleidoscope of vibrant colour. Some will argue, that you can technically do all this right now, of course, if you know where to go and on whose car you need to place a tracking device, but imagine if it didn’t have to be that way, shrouded in secrecy and subterfuge? Imagine instead that it was easily accessible, well managed and promoted sustainably; that these endangered species were not only brought back from the brink, but regularly stocked in many of the rivers where they existed for thousands of years.
If things work out the way Jeremy believes they can, we won’t have to imagine this at all.
DONATE …directly to the fund-raising efforts for the Saving Sandfish project via Givengain.
givengain.com/cc/saving-sandfish
CHECK OUT…Fishwater Films on Instagram (@fishwaterfilms) or visit their website to watch their Saving Sandfish films and stay up to date with other initiatives. fishwaterfilms.com
