Date: 8/28/19 8:42 pm From: Roger Kuhlman <rkuhlman...> Subject: Re: [birders] OT Monarchs
Monarch populations fluctuating substantially up and down over the years. Right now they seem to be doing fairly well in southeast Michigan but I would add several cautions. Because of the changes in agricultural practices there is almost no common Milkweed in farm field or along farm fields in Washtenaw County these days as compared to even 10 to 15 years ago when there was a lot to be found there. That fact signals a big warning flag for the prospects of future Monarch populations in the region. An even bigger long-term threat is to be found in the Mexican overwintering grounds for eastern Monarchs. These are relatively small areas all closely concentrated and are as result subject negative impacts from human development and deforestation and random adverse weather effects. It is quite possible to imagine something really bad happening at the Mexican wintering sites that ends forever the annual eastern Monarch migration.