As one who has been looking for and photoing migrants for many years, I was happy to see the 20o temps this a.m. The old lilac that harbored an AMRO nest last year 4 ft from my backdoor, has leaf buds on it the last several days. The same with the very old native Prairie Crabapple where BCCH's and HOWR's have nested. As springs have been advancing in the calendar with warming temps, the trees often leaf out before the mid-May migrants arrive at 45o latitude.
Plants bud and leaf according to temps, while bird movement is cued by daylength. Early leaf-out makes seeing and photoing birds difficult as you all know. A bigger problem may be out-of-synch food availability, depending on larvae spp and bird spp, due to climate change. (I assume insect activity is also stimulated by air temperatures.) Later migrants might find less food available. The biggest problem is the general decline in bird numbers across genera and families in N America. So fewer birds to find each year and harder to see the ones you find. So killing frosts in March ---Yes. 60o- 70o temps --- No. GAndersson/ St Paul ---- Join or Leave mou-net: http://lists.umn.edu/cgi-bin/wa?SUBED1=mou-net Archives: http://lists.umn.edu/archives/mou-net.html During the pandemic, the MOU encourages you to stay safe, practice social distancing, and continue to bird responsibly.
