South Africa is in the midst of a freshwater fish conservation crisis, but what if there was a way for anglers to help protect our freshwater fishes and restore their river ecosystems? As fly angler Dr Jeremy Shelton of the Freshwater Research Centre writes, snapping an image of your catch with a smartphone and uploading it to a citizen science app could make a bigger difference than you think.


South Africa’s freshwater biodiversity crisis

Every four years South Africa’s National Biodiversity Institute (SANBI) takes stock of the country’s biological diversity by undertaking nation-wide assessments of plant and animal life to help focus limited conservation resources where they’re needed most. The most recent National Biodiversity Assessment was completed in 2018 and the results were alarming.  Freshwater fish emerged as the country’s most threatened species group and freshwater habitats, (including both rivers and wetlands), have become more degraded than any other ecosystem type. A strong message emerging from the assessment was that urgent conservation action is needed if we are going to save our threatened freshwater fishes and restore the fragile habitats in which they live.

The knowledge gap that’s holding back freshwater conservation

Critical to successfully conserving our freshwater fishes is a solid understanding of where the different species occur, and how their distributions are changing. South Africa is home to 134 species of freshwater fish (27 of which are non-native species introduced from elsewhere).  However, our knowledge about the distributions for many of these fishes, especially the rare and endangered ones, is poor, which is holding back conservation efforts to protect them.

Truth be told, South Africa’s government-funded departments, institutes and organisations mandated to monitor and manage biodiversity simply do not have the capacity to do the surveys needed to track changes in the distributions of our freshwater fishes , a situation highlighted in a 2016 paper by former CapeNature freshwater fish scientist Dean Impson. That is not to say that good work is not being done.  Scientists are doing what they can to keep track of which fish are where, but studies and surveys are generally limited to short (typically 2-3 year), grant-linked time scales and usually centre around one or two focal species.

In short, we are fast losing track of which species occur where, and of how their distributions and populations are changing. This is especially true for rare species or those that inhabit remote or difficult-to-access areas like steep gorges, overgrown tributaries and places off the beaten track.

Former CapeNature freshwater fish scientist, Dean Impson, hoists a Clanwilliam yellowfish caught on a recent survey of the Doring River in the Western Cape.

The rise of citizen science

The term “citizen scientist” may sound off-putting at first, but citizen science might just hold the key to narrowing the fish distribution knowledge gap and improving freshwater conservation here in South Africa. In essence, a citizen scientist is anybody who makes an observation of a plant or animal, keeps a record of it and shares that record with scientists. But it’s really the advent of the smart phone that has revolutionised citizen science over the last decade. In 2008, a mobile application called iNaturalist was launched and within a decade it became the go-to platform for citizen scientists from around the globe to store and share their biodiversity observations. Today the platform hosts over 100 million biodiversity records, including 1 million records of fish.


iNaturalist – a game-changer for mapping species distributions

How the app works: Using iNaturalist is straightforward and the interface is clean, fun and intuitive. Getting started requires three basic steps: (1) download the iNaturalist app and sign up (it’s free), (2) take a photograph of a plant or animal and (3) upload your observation and suspected species identification (your smartphone will automatically share the observation date and location with the app). Any photo records of freshwater fish (taken both above and below water) in South Africa will automatically be added to an iNaturalist project called “Freshwater Fish South Africa” where experts can help with confirming species identifications.

But here is where things get interesting: once a record identification has been confirmed by at least two experts, it is considered “Research Grade” and can then be used by scientists in national biodiversity assessments and conservation efforts. Moreover, a new platform called the Freshwater Biodiversity Information System (FBIS) developed by Cape Town-based non-profit the Freshwater Research Centre has engineered a way to harvest research grade fish records and inject them directly into the coalface of freshwater conservation and decision-making at a national level.

A fly fishermen gently cradles a mature male Clanwilliam sawfin before releasing it back into the wild unharmed.

How fly fishermen can help

To date, the numbers of iNaturalist records in South Africa for groups like insects and birds are impressive, totaling ~150K and ~130K respectively. Freshwater fish on the other hand, have a mere 1600 records uploaded thus far, with limited contributions by fishermen. However, it’s the fishermen, especially fly fishermen, who are out there on the water catching and observing fish more often than anyone else, frequently in remote and difficult-to-reach places where knowledge of fish distributions is particularly poor.

Scientists survey freshwater fish populations in a remote stretch of the Doring River.

There is thus great potential for fly fishermen to ramp up these observations for the benefit of freshwater fish and ecosystems. Fortunately, the app also has built-in options to obscure or hide exact record locations for cases where one may want to keep the location of the exact location under wraps. As citizen scientists armed with the iNaturalist app, South Africa’s flyfishing community has an opportunity to vastly improve our understanding of our country’s freshwater fish distributions in a way that will help prevent extinctions, keep track of invasive species and better conserve priority freshwater habitats, ultimately promoting more sustainable local fly fishing into the future.


This story first appeared in issue 35 of The Mission. Read the rest of that mag below. As always, it’s free.



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