Rare Tansy Beetle

Here are two rare Tansy Beetles trying to perpetuate their species.
The main colony of these is in an area about 45km. In diameter centred on the city of York. We found them on Tansy plants on the banks of the River Ouse.
They cannot really fly so if the Tansy on which they live dies out they have to walk to find another. Even though Tansy gives off an odour the beetles cannot smell it.

Tansy is threatened in places by invasive Himalayan Balsam. It also looks like Ragwort so people tend to pull it up in error.
Fortunately in York there is a group of volunteers who give some of their spare time helping the Tansy Beetle to survive.