Mist net sunrise on Metinic Island
It’s 3:45am and alarms are ringing on Metinic Island (they’re set at a more hospitable 5:00am in the fall). Mist nets, used to capture passage-migrants that have landed on the island, are open and active at first light. Migration monitoring is underway!
As many of you following this blog are aware, the refuge-owned portion of this island has been managed as part of a coordinated seabird restoration effort in the Gulf of Maine for the last thirteen years. But, what happens on Metinic before and after the seabird nesting season? It turns out, A LOT, as was discovered in the fall of 2009 and substantiated through spring and fall migration monitoring efforts since.
Just who are these early risers and what are they doing? Migration research on Metinic is a collaborative effort between the Refuge and the University of Maine’s Holberton Lab of Avian Biology. A variety of techniques including visual surveys, acoustic sampling (recording species specific calls given by migrants flying over at night), and banding are being used to monitor bird movements on Metinic. Results of this ongoing research have since led to an international effort to document bird movements throughout the Gulf of Maine region. 
Left: The “catch” from a busy net round. Birds captured in mist nets are brought back to the banding tent in cloth bags and await processing before being released. Above: This adult male American Redstart was one of more than 600 birds captured on the island this season, a total achieved even with weather precluding banding on almost half of the days.
Photo showing a diverse array of band sizes from hummingbird to hawk. The inset picture is included to provide scale for the hummingbird band, which comes printed on a flat sheet of metal and is shaped into bands by each bander.
This spring, migration monitoring on Metinic began on 1 May and continued through 7 June. Of the techniques mentioned above, banding, in particular, offers the unique opportunity to study birds in the hand and provides detailed information about individuals. Nets are checked regularly throughout the day and birds brought back to the banding tent are fitted with a small aluminum band containing a unique nine-digit number. Essentially, a “social security number” for each bird. Birds are then aged and sexed, a series of measurements are taken (which provide information about the size of the bird and its energetic condition), and then each individual is promptly released.
Jennie releasing a Common Yellowthroat after processing.
Importantly, while anecdotal observations of migrants have shown that Metinic, as well as many other offshore islands in the Gulf, provides valuable stopover habitat for many species of birds during migration, specific use of islands by migrants has not previously been studied. With proposed and planned energy-related developments throughout the Gulf of Maine, migration research on Metinic, and throughout the region, is especially timely for identifying potential threats these developments may pose to migrants.
Stay tuned for Part II, where we’ll feature select species captured this season!
Authored by: Adrienne J. Leppold with Courtney Viall (and special guests Charlie Walsh and Jennie Wiacek)
