Is there a link between eye colour and haemoparasite infection in the Southern Boobook Ninox boobook in the Perth Metropolitan Area?

Abstract

The Southern Boobook Ninox boobook most commonly has a yellowish to greenish or greenish-hazel iris, but in the Perth Metropolitan Area a relatively high proportion of this species has eyes that range from a dark greenishbrown to dark brown. This trend seems to provide some initial evidence of an incipient genetic polymorphism within this population. The darker eye colour may also play a signalling role in sexual selection. An increase in disease consistent with haemosporidian infection has also been noted in recent years, possibly involving known Leucocytozoon or an aberrant Leucocytozoon -like species. Ongoing exposure to these parasites might have imposed selective pressure for increased resistance. Although this is explored here in some detail, it is possible that this phenomenon is associated with some other unidentified factor, or a combination of factors, so further investigation into this area may be rewarding.