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Another strike out again last night.
I absolutely agree with you that banding the Owls would give us a much more clear picture of what might be going on in regards to ages and sex of the Owls and important migration information if we could re-trap banded Owls. Thank you very much for your information jessie in regards to the NSWO banding project at Rocky Point this year. To band 20 Owls within 6 hours on one night is amazing data. It continues to show that the funnel point through Rocky Point continues to be a major route. It also confirms for me that populations on the Island and throughout the interior remain stable and that is good news.
Guy,
I agree with you. On birders sighting alone it would indicate that the NSWO do not migrate. On the small studies that I have completed to date and these studies have only included the Lower Mainland area, it looks like that NSWO may be altitudinal migrants. I know here on the coast the re-hab centres receive the majority of their Owls between September - December and it's also when the largest numbers are reported through sightings. There are many things that may contribute to this. Coming down from the mountains into more populated areas, easier to see as they can't be hidden as well through leaves on the trees etc. However going through the Vancouver Area Checklist, they are seen throughout the year and are also indicated as being uncommon in all 12 months of the year with no increases at particular months. Using playback for NSWO has also worked for me through different seasons and months. However I'm not able to sex and age a bird on site alone and therefore can't answer the question if they are young Owls, adult males holding territory, or nesting/breeding Owls. Until now the results from trying the band these Owls have not been successful and I have no statictics on ages and sex.
One thing I have not done yet is go into the BC Breeding Atlas data base and conduct a search on NSWO. Funny how you can put much time and effort into a project and forget something that's right in front of your face. That will be my next step and I'll find out if there has been any kind of nesting/breeding activity throughout the Lower Mainland. It might also help us with the migration question.
Thanks again to everyone who has participated in this discussion. Anyone with anything to add is most welcome. You might not think a sighting or information is important, but every little bit helps.
_________________ Best in Birding! Les Lee (West Van) http://birdtrekkerbc.com/
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