Distribution of Contributions in Volunteer-generated Datasets : Gall or Fruit Fly Records

I remarked in my OpenCageData interview that I see many similarities between biological recording and OpenStreetMap contributions. Indeed, I've had some interesting discussions about this with Prof. Muki Hakaly at UCL. Muki's group now do extensive research across the gamut of activities which fall under the rubric of "citizen science", so I'm hopeful that they will elucidate which features are common across this spectrum.

A female Chaetoraellia jaceae, a tephritid fly whose larvae feed on Knapweed.
Photo: (c) mausboam, Flickr.

Basically, we know that there is a very long tail of smaller contributions to OpenStreetMap. Both Harry Wood and Frederick Ramm gave presentations on aspects of this at SotM-14 in Buenos Aires, and Richard Fairhurst also touched on this at SotM-US in 2013. Very recently Marc Zoutendijk has used data collected by Pascal Neis to examine a cohort of new Dutch OpenStreetMap contributors from 2014 and 2015.

The usual hope expressed by people doing this type of analysis with OSM data is that by better understanding of these contributions we can improve the number of people who continue to contribute after the initial sign-up and first edit.

My perspective is slightly different, because it is coloured by knowledge of the much longer history of biological recording.

Bat Bridges, or why deleting lonely tags is a bad idea

The other day I was idly browsing the blog of Mark Avery, the former conservation director of the British bird protection society, the RSPB. One item caught my attention: it was about 'bat bridges'. Although I hadn't heard of them before it was pretty obvious what they might be.

A bat bridge on the A590 in Cumbria

Bats tend to follow linear features in the landscape when foraging at night, at least in part because they provide protection from predators. Bats tend to avoid flying over open spaces. Hedgerows, edges of woods, and so on, form commuting routes between roosting and feeding sites for bats. When these are damaged or destroyed, for instance by road building, bats either lose feeding locations or have to cross the open space. Usually they do this by flying low: effective against their age-old predators, but not much help when confronted by a car.