''Trends and Abundance Patterns in the Purple Martin''

[Guest]

The subject article is subtitled "Results of the North American Breeding Bird Survey, 1966-1994." It can be found here: www.purplemartin.org/update/Trends.html

I found it interesting to compare the article's Fig. 1 map with the PMCA's 2005 map of Scout Reports.The latter's general area of few reports in a band going northeast from northern PA through ME corresponds to the region's low density of Fig. 1. However, I see marked differences between the maps for the western region of the USA. In particular, there are no Scout Reports for AZ, whereas Fig. 1 shows a "hot spot" in southern AZ. Further, the Fig. 2 map shows increasing density for this region.

Is there any data that is more current than that of 1966-1994?

Tony

[Daniel Airola]

The breeding bird survey information is available through 2004. I can't give you the URL because the site was down when I tried to access it. Type "Breeding Bird Survey" in Google or another search engine and it will come to the top of the list. The scout map shows few records for western birds because most martins (except in OR, WA, and BC) are nesting in natural cavities rather than nest boxes or gourds, and the species is relatively rare in the west. So scout records in the west reflect the distribution of the relatively few landlords, researchers, and conservationists that pay attention to martins and are hooked up with PMCA, rather than the distribution and abundance of martins.

I wish we could get more reports from throughout the western range, so encourage anyone reading from this area to start monitoring sites for returns. I have found the average return dates shown for west coast martins shown at the bottom of the scout page to be pretty accurate.