Why do female Flightless Cormorants abandon their brood?
Among the variety of mating strategies employed by birds, polyandry;when females take multiple male partners in a single season;occurs rarely, usually requiring unique environmental pressures for the behavioral adaptation to develop (Emlen, 1978). Such is the case for the Flightless Cormorant in Galapagos: like other marine organisms in the archipelago, it is subjected to great fluctuations in its food supply. Flightless Cormorants have evolved a serial polyandrous mating strategy, in which females abandon their mate and clutch after hatchlings fledge, proceeding to attempt a second mating in a single year. This paper will explore the question of why female desertion (i.e. serial polyandry) evolved in the Flightless Cormorant. I will begin by considering the environmental pressures on the cormorants, and how desertion by one parent may increase reproductive fitness in harsh conditions. I will then proceed to assess the relative costs and benefits of serial polyandry for both females an
