Smart waders go fishing for science

By Jonathan Amos
BBC Science Correspondent, Vienna

Fly fishingImage source, Thinkstock
Image caption,
Both the angler and the hydrologist have an interest in water temperature

The genteel pastime of fly fishing is set to enter the smartphone age.

A Dutch team is developing clever waders that enthusiasts can wear to find not only the ideal location to fish, but to collect key hydrological data for scientists.

Of most use to both groups would be waders that sensed water temperature.

Anglers know this influences where fish go in a river and, for researchers, it betrays details about the movement of water in that river and its chemistry.

"We need more data from more streams than we could possibly monitor with our sensor networks," explained Rolf Hut from Delft University of Technology.

"Wouldn't it be nice if we had citizens walking around in the water, interested in temperature because they want to know where the fish are, and at the same time providing us with the information we can use for our research?"

The data would be collected by a simple temperature probe in the wader boot. This would then travel up a wire to a Bluetooth device above the waist to be passed to a phone in a dry pocket.

The angler could use the information straightaway to decide where to stand in the river and cast their fly, while the scientists would receive the details back at the lab over the cell network for later analysis.

Media caption,
Rolf Hut: "Depending on cost, we could put even more sensors in the waders"

Dr Hut and his colleagues are interested in the study of hyporheic exchange, which describes how water moves into and out of a stream through its bed.

In dry periods, a stream will lose water into the ground; in wet periods, it will gain it - and where the water comes into the stream, it is usually much colder than what it is joining.

It used to be thought this was a fairly gradual process along a stream's entire length, but scientists now realise that the exchange in some locations is actually far more significant than in others.

The team's smart waders are in the earliest phase of development, but Dr Hut was able to demonstrate the concept at this week's European Geosciences Union General Assembly - albeit in the rather warm and dry setting of the meeting's poster hall.

Image source, Thinkstock
Image caption,
Healthy rivers mean healthy wildlife and a good stock of fish

Then there is the question of extending the range of sensors incorporated into the waders.

Rolf Hut added: "Why stop at temperature? What about water depth?

Image source, Rolf hut
Image caption,
Rolf Hut is a fan of "citizen science" approaches to collecting data for research

"For hyporheic exchange, it would be interesting to look at salinity; pH would be really interesting for water quality.

"And now there are sensors coming on the market that would do water quality parameters like nitrogen levels, dissolved carbon levels - that are really telling you how healthy a stream is.

"So that's not necessarily for hyporheic exchange, but for other fields of hydrology and water management. And that's in the interest of the fishers, by the way, because you need a healthy stream to have fish."

Dr Hut's attire at the meeting prompted a chuckle of two from fellow hydrologists, but also admiration for the ingenuity.

Nicholas Howden from Bristol University, UK, said: "Hyporheic exchange is a fascinating topic.

"For example, groundwater that comes into rivers tends to be very rich in base cations - the kind of stuff salmon need. They will spawn in gravel beds where there is upwelling.

"So, these are locations that are ecologically very important for the river."

The idea of the smart waders originated from a talk with Scott Tyler of the University of Nevada, Reno.

Image source, Rolf hut
Image caption,
The waders are in the early prototyping stage

'Hack' your phone

Image source, Getty Images
  • Modern smartphones are packed with sensors, including accelerometers, magnetometers, barometers and proximity sensors.
  • Smartphone technology has been used to control satellites and test for illnesses. and follow me on Twitter: @BBCAmos