As hundreds of thousands of eagles, hawks, and vultures make their annual journeys from Canada and the United States to southern overwintering grounds, many of the dedicated observers ascending to Hawk Watch sites throughout North America to document their travels are also recording coincident migratory dragonfly observations. This week, as peak numbers of hawks (and dragonflies) make their way south, the Hawk Migration Association of North America (HMANA) celebrates the annual spectacle with its 1st annual International Hawk Migration Week. Though the details surrounding the spectacular flights of dragonflies are not nearly as well-known as for raptors, we do know that fall is also peak migration season for these remarkable insects making their southward voyage. The most notable dragonfly migration flights are often witnessed along the rugged coastlines of western North America and the Atlantic seaboard to the east, but observations at inland Hawk Watch sites throughout North America are fundamental to our understanding of migratory routes and are contributing valuable data to further our understanding of this phenomenon.
Since its inception in 1974, HMANA has organized an international effort to promote raptor conservation through migration monitoring, fueled by the enthusiasm of citizen scientists throughout North America. Dragonfly migration is sporadic and discontinuous, and many events may be missed if observers don't happen to be in the right place at the right time, especially on a day when migrant numbers are lower. However, because raptor observers are stationed consistently at HMANA Hawk Watch sites throughout the migration season, they are perfectly positioned to make note of passing dragonflies following the same routes as the birds. Many hawk counters have already been taking informal note of migrating dragonflies at their sites, in some cases for years, either from a general interest in insects and/or as a way to pass the time when raptor numbers are low. It makes good sense for the counters of winged things to work together, and last year HMANA was recognized as a key partner in our quest to understand the migratory marvel of dragonflies.
In 2013, HMANA partnered with the MDP to develop a protocol to formally monitor dragonflies along with their regular raptor observations. Over 30 hawkwatchers from 18 observatories reported almost 11,500 dragonflies passing through their counting posts from August through November last year. Common Green Darners and Black Saddlebags, North America's common eastern migrants, were the most abundant species counted on the wing. Twelve-spotted Skimmers followed in individual numbers, leading us to believe this species may be more of a regular migrant in the east than previously thought. As reports of late-emerging individuals of migrant species continue to come to us from the northern US and even Canada, we wonder if these individuals will also amass and take wing to follow similar bird migration routes.