By Peter Stewart

Invasive prickly pear cacti (Opuntia) are a serious problem in Laikipia County, Kenya. This invasive plant spreads rapidly across the landscape, turning diverse habitat into a green hell of pads and spines. As invasive plants like prickly pear spread, they can alter the behaviour of wild animals, triggering a cascade of consequences which impact on the ecosystem and the communities who inhabit it.

A stand of invasive prickly pear (Opuntia engelmannii) at a heavily-invaded site.

In a new project, our team from Durham University’s Conservation Ecology Group, in collaboration with Mpala Research Centre and Loisaba Conservancy, is working to understand how prickly pear affects the habitat use of wild mammals – a key aspect of their behaviour.

To achieve this goal, we are using motion-activated camera traps to record how many animals of each species are using sites invaded by prickly pear, and then comparing these numbers to nearby sites with little or no cactus. The camera traps also provide information about how different species interact with the cactus, whether eating its fruits or spiny pads, eating other plants which grow within the cactus stands, or using the cactus as cover to hide from predators.

An elephant feeds on the fruit of Opuntia engelmannii.

To process the huge number of photos collected by the camera traps, we need your help! We have set up a project on the online citizen science platform Zooniverse, where anyone can view the camera trap photos and classify the animals in them. You can click here to visit the project home page.

Before uploading images to Zooniverse, we pre-screen them with the machine learning tool Megadetector to filter out empty images – this means that most of the images on our Zooniverse page have animals in them!


By Hannah Campbell

The population of reticulated giraffe, one of the most iconic mammals on the planet, has declined by over 50% over the past 30 years – from 36,000 to just around 15,000 today. Poaching, loss of habitat, and land degradation are all pushing the giraffe toward an ominously named “silent extinction.”

To effectively help protect the reticulated giraffe, researchers must first understand how these towers of the savanna use their habitat. Over 100 motion-activated cameras have been installed both here at Loisaba Conservancy and at Namunyak Community Conservancy to the North East. A local team of Twiga Walinzi (which means Giraffe Guards in Swahili) is conducting field research to study and identify individual giraffes, while monitoring field cameras, engaging with local communities, and removing poachers’ snares from the conservancy sites.

During the course of a year, over 1,000,000 images are captured by these cameras! Although placed to monitor giraffes, they also photograph many different species, from warthogs to lions!

This means millions of photos need sorting through to classify what each shot has captured, which is where you can help! An online citizen science project called Wildwatch Kenya was set up to allow anyone from around the world to review and help classify the images.

Once these images are classified, and along with data from collared giraffes, researchers can identify specific areas that are favoured by giraffes and start to look into why they prefer certain habitats. This information is critical in order to provide better protection to those areas, as well providing insight on where to focus any community outreach to help reduce poaching where people may be living closer to giraffes. “The faster we can sort through these images, the faster we understand what is needing to protect reticulated giraffe in these areas” – Jenna Stacy-Dawes, San Diego Zoo Global.

Click here if you would like to help classify some of the camera trap images from the field!