The three-spined stickleback (Gasterosteus aculeatus) is one of the few Finnish fishes to build nests. The colourful male digs a small depression on sandy or stony bottom and carefully builds a mound of plant parts to cover it. Females come to observe first the male, and if he turns out acceptable, his nest. In this point, the male has directed the female to his nest entrance, and now hovers anxiously behind her, waiting for her decision.



An illustration for the Finnish newspaper Helsingin Sanomat, on an article discussing the surprisingly complex behaviour of fishes. In the article, three-spined stickleback was dubbed as the best architect of the Baltic Sea.



I'm not perfectly happy with it, but as there was only a couple of days to do it, I had to stop somewhere. Anyways, it's black markers on a sketchbook, and digital colouring.