|I photographed this Clark's Nutcracker in northern Utah on 28 July 2013, but if it can't find enough pine nuts, it might be headed to your neighborhood.|
On Tuesday, a couple friends and I were birding in the middle of Cache Valley, at about 4,500 ft. elevation. This is well below typical CLNU habitat, especially in summer. In the seven years I've lived in this area, I know of just a few credible reports from the valley, almost all from the "benches" very near the mountains and all between October and December. Yesterday, we saw a flock of 28 Clark's Nutcrackers flying over the middle of the valley, barely in to September.
|This is what a Clark's Nutcracker can look like in a good year, with a crop full of pine nuts that it will cache around the area to feed on in the winter. I photographed this one in 2011 in northeastern Nevada.|
In both 2011 and 2012, pine cone production by whitebark pines, one of the nutcracker's two main food sources, was higher than average. The very dry winter last year (about 60% of typical snowpack locally, and around that or lower in much of the inland west) has caused poor production by whitebark pines this year, in Wyoming the lowest since about 2002. Coincidentally, in 2002, Clark's Nutcrackers were reported from as far out of range as Alabama and Missouri.
|This figure shows the standardized whitebark pine production from the Greater Yellowstone ecosystem for the last 24 years. Note that both 2011 and 2012 were above average years, but 2013 is about the lowest since 2002. This figure is from here and is in the public domain.|