How technology helps us understand Blue Crane movements
The Western Cape, especially the Overberg region, is the best place in South Africa to see our beautiful national bird, the Blue Crane.
Here you’ll see Blue Cranes in greater abundance than anywhere else in the world.
The Blue Crane was listed as Vulnerable to extinction on the IUCN Red List, after numbers in the eastern grasslands declined dramatically. As cereal agriculture expanded in the Western Cape, Blue Crane numbers have blossomed.
This can also be attributed to the great efforts of farmers going out of their way to protect them, with support from the Overberg Crane Group and Endangered Wildlife Trust.
Still, these birds face many challenges in the agricultural landscape, like powerline collisions and disturbance during breeding.
At the moment, it’s uncertain whether the Western Cape Blue Cranes will continue to thrive, given climate change and expansion of power infrastructure to meet our growing human population.
Now we’re trying to answer some of these question.
Work by Sydney Davis and Julia van Velden gave us some fascinating insights into these issues, but much is still uncertain.
Christie Craig (Endangered Wildlife Trust/FitzPatrick Institute of African Ornithology) plans to provide clarity on these uncertainties through a three-year PhD research project.
This map shows the locations where chicks were ringed and released, the three bands indicate the colour ring combination on the right leg.
An example of the data that we receive from these trackers, once the Blue Crane chick began to fly, it moved locally around the nest site. Recently it made its first movement away from its nest site, a distance of just over 10 kilometres.
Bradley Gibbons and Anne Lacy about to release sibling chicks in the Swartland. The hood over the cranes eyes helps keep them calm while we fit the rings.
Among the questions Christie is asking:
How do juvenile Blue Cranes move on a daily basis in the agricultural landscape? And when and where are they most at risk of colliding with power infrastructure?
To help answer these questions, Christie and the team fitted satellite trackers to Blue Crane chicks in February this year. Max Planck Institute designed 1000 of these trackers for crane species across the globe. So far trackers have been fitted to 12 Blue Crane chicks in the Western Cape and 11 Blue Crane chicks in the Karoo.
How do they work?
The trackers log locations as the bird moves and then sends the data to a central online database via the cellphone network. The tracker is a small black box with a solar panel, mounted on two rings that we clip around the leg of the crane. The design of these devices was tested extensively on captive birds at the International Crane Foundation. They found no harmful effects to the birds.
We fit the trackers on chicks shortly before they can fly. Once we catch a chick, we put a hood on its head. This keeps the chick calm. (In fact some chicks even have a nap while we fit the rings!) Each chick with a tracker also gets three colour rings on the other leg.
HERE’S WHERE WE NEED YOUR HELP:
If you spot any of these cranes, we’d love to hear about it. You can send your sightings and any questions you have about the research to Christie Craig (Phone/WhatsApp: 066 289 5988 or Email: christiec@ewt.org.za).
A note from Christie:
“We’re very grateful to all the farmers and farm staff who welcomed us on their farms and assisted us with this work. We are very thankful for the advice and support from the FitzPatrick Institute, CapeNature, Overberg Crane Group, Overberg Renosterveld Conservation Trust, SANPARKS, Camdeboo Protected Environment, the Nuwejaars Wetlands Special Management Area, and many others. Lastly this work would not have been possible without support from the Leiden Conservation Foundation.”