To update an earlier post on the subject, I received an email back from Roy Smith about how Toronto sightings are compiled. Unfortunately, the Greater Toronto Area Bird Checklist and Reporting Guidelines of 2000, written by Glenn Coady and Smith, is out of date (excellent, but out of date). Year to year, the significance of individual species sightings can change drastically. Take, for example, this year. At the end of 2007 and into 2008, the guidelines changed to include all sightings of Common Redpoll concentrations as well as Pine Grosbeaks to monitor the invasion of winter finches due to seed crop failure in the north. Another Toronto-specific example is the Glaucous Gull. Pre-2000, the cutoff # for reporting this species was 5. Now, however, all Glaucous Gulls are to be reported after the Keele Valley Landfill was shut down as fewer birds are now seen. Another good example, as Roy explained, is the case of birds affected by the West Nile virus. American Crow apparently has very poor data at the current time because very few people report sightings of this species (particularly numbers). Therefore, the only data for the GTA area on the crow is from Christmas Bird Counts or other specific events through the year. Smith also informs me that the number of people reporting in the GTA has dropped significantly, an unfortunate problem that I bet almost every area compiler experiences.
As of now, I do not believe the GTA has a seasonal status book like most other areas do. Bob Curry's book on the birds of Hamilton is excellent and Point Pelee has decently updated seasonal bars, but ideally, a book will be published for Pelee exploring early and late migration dates, peak numbers, and notable sightings. Personally, I think seasonal statuses can be a great learning tool, even if they are only averages and the next year might prove quite different from that preceding it. Although the status and distribution of birds is static and ever-changing, there is always the need to keep reports and observations up to date, not only for the benefit of birders but also to monitor populations. Particularly now, as climate change will no doubt largely affect movement, migration, and distribution of many North American species.
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