The male MOORFROG (Rana arvalis) turns a bright blue during the mating season. This change of clothes only last for a few days, then they return to their usual brown color. If you want to photograph this beautiful blue suit, you need to be at the right place at the right time, usually around March 20 here in Holland. You can find them in shallow pools with slightly acidic water. In the western provinces of our country, they are rarely seen, so check the distribution map.