Satellite tracking of Blue Cranes: What the data shows us
BY CHRISTIE CRAIG
(EWT researcher and OCG Extension Officer)
Satellite tracking devices fitted on Blue Cranes in the Overberg are now providing vital information
on how these cranes move about, and where they’re most at risk of powerline collisions.
The African Crane Conservation Programme team (made up of the Endangered Wildlife Trust and the International Crane Foundation, including OCG Extension Officer, Christie Craig) has already fitted satellite trackers on five cranes in the Overberg (and two more in the Swartland). The team plans to fit another seven trackers in the next few months.
What we’ve found so far:
To date, the crane’s movements have been quite local – with the individuals staying close to the area in which they were tagged. One crane has, however, left the Agulhas area, and is now moving around north of Napier.
Here’s how the African Crane Conservation Programme team go about fitting the tracking devices:
- We trap cranes around sheep troughs where they like to congregate during the winter. Once captured, we put a hood over the crane’s eyes to keep it calm while we work.
- The small satellite tracking device sits on the crane’s back, attached with a harness. It’s very small, and does not affect the crane’s ability to fly or move about naturally. The devices work off the iridium satellite network, much like a satellite phone. The device sends the crane’s location and height every time it moves 200 metres from its previous location, allowing us to get data every time the crane makes a significant movement.
- The crane also gets some colour rings so that we can recognise them afterwards.
Why are we doing this?
Tracking Blue Crane movements can tell us a lot about how to protect these beautiful birds. One of the main threats to cranes is collision with powerlines. Using the data we get from satellite trackers on Blue Cranes, we can look at their flight patterns to understand when and where they are most at risk of colliding with powerlines, by modelling the data. This in turn can help Eskom make decisions about mitigating powerlines to make them safer for cranes.
The EWT and the OCG work in partnership to protect Blue Cranes in the Overberg. The EWT and the International Crane Foundation work together in furthering conservation of cranes and their habitats throughout Africa. The EWT Western Cape project is supported by the Leiden Conservation Foundation and Eskom.
Image credit: Christie Craig and Sharon Brink