There was no obvious choice for today, so I decided to pick a species from my favorite family of birds - the warblers. Everyone that I know enjoys spotting a Canada Warbler on migration because it is a striking bird, although few birders are drawn to its song. As I did today, on a "northern" BBS one often must concentrate extra hard at stops featuring wooded wetlands to listen for its rather soft, jumbled song of a few notes, each seemingly on a different pitch, from all of the competing, often louder songs. It is a long distance migrant, wintering in and around the forests of northwestern South America.
I consider the Canada to be an uncommon species, and often the BBS is not so good at monitoring species having low populations. However, this raises the question, how do we adequately monitor the Canada Warbler population? In general, BBS data show its population to be in a long-term decline. The trend is similar in both the US and Canada - about a 1.9% decline annually since 1966. The relative abundance per BBS route is greatest in New Brunswick (3.5 individuals/route) and ME (1.8 birds). Descriptions of its habitat often include attributes such as large stand size, dense patches of shrubs or saplings, and a lush groundlayer.
Its WBBA distribution is interesting. While it has a decidedly northern distribution as one would expect, there are several, isolated, outlier (disjunct) populations. I suggest that these outlier sites be identified as potential sites for consideration as Important Bird Areas (IBAs). As Eric Epstein, the author of the Canada Warbler species account for the WBBA states, "Determining the factors responsible for the Canada Warbler's long-term decline is a high priority for researchers, conservationists, and birders."
This species highlights the prime reasons why I embarked upon my Quad 30 Campaign. We need robust, long-term, bird monitoring programs like the BBS, and we need to identify, protect, and manage those areas in our states that are most important to birds!