May is actually our favourite month in the islands. As well as a very pleasant climate, you have the Waved Albatross on Espanola (Hood) in full courtship mode.
By May the trade winds have returned to Galapagos which brings a gradual cooling of air and water temperatures compared to previous months, which are characterised by more a intense, hot climate (arguably May and June are the most pleasant climate in Galapagos). In May you still have lots of blue skies.
Waved Albatrosses mate for life, and can live for up to 50-55 years and their courtship displays are really quite something to see. The courtship of the Great Frigatebirds on Genovesa (Tower) island, the other outpost island for seabirds is also in full swing as the males puff out their red gullet sacks puffed out it is quite a spectacle. Blue-footed Boobies also join the party, and begin their courtship rituals too, which again is quite something to see!