13 December 2010

A Quick Word on Hybrid Gulls

If you’re a gull enthusiast, then you recognize the great propensity for gulls to hybridize - especially the large white-headed gulls. I remember a time not too long ago when I approached every hybrid gull with a sense of urgency and the feeling that there must be one correct answer to the identification. Much of this rigid approach where notions are only perceived in black and white is unquestionably rooted in naivety. I’ve come to accept that many - if not all - hybrid identifications are tentative and to a great degree nothing more than “educated guesses”. These educated guesses are based on inferences that are derived from our experience with the presumed parent species. Some of these identifications could be very convincing and more plausible than others, but this I imagine comes with a great deal of experience and knowledge. I could proudly say that I’ve become more and more reluctant to resolve hybrid IDs with words such as “surely”, “certainly” and “definitely”. Some exceptions can be made for known phenomena hybrids such as Olympic Gulls (Western X Glaucous-winged), but a level of uncertainty is presented in some of these individuals as well.

I find it interesting that there are usually 2-3 differing opinions offered by birders as to the origins of a hybrid. I feel it’s very beneficial to scrutinize the counter arguments presented by others and to try to see what features and marks they’re picking up on that I may have overlooked. I’d like to suggest that the process of assessing a hybrid should be more important than assigning a name. I've found that assessing hybrids helps me reinforce a lot of what I know about the presumed parent species and I almost always learn something new during the process. For some, thinking about hybrid gulls in this manner is maddening; I think this is mainly because having to apply higher level thinking skills without arriving at a conclusive ID seems like a wasted effort for some birders. After all, most of us took up birding so that we could relax. Unfortunately, these birders demand a name for every individual they encounter in the field and this, I’ve learned through personal experience, is an imprudent expectation to have of nature. Nature is not always tabulated in Systema Naturae. I think the sooner one’s thinking "evolves" to this reality, the sooner hybrids become more enjoyable.