February

Calanus can be killed by small concentrations of the delousing agent hydrogen peroxide.

Large doses of teflubenzuron kill – small doses cause stiff joints. The question is how small.

Millions of cleaner fish are used in farm cages to eat lice off salmon every year. However, there is limited research into how efficiently they do this job. Now scientists have gone through all published studies in the field – and found large knowledge gaps.

And that is just one of the challenges that seals face in a changing world.