SITE DESCRIPTION

Michigan has more than 3,200 miles of coastline - more than any state in the lower 48. While this coastal zone is a place of unique biological richness, it is also a place with heavy human demands. We studied migration along the northern Lake Huron shoreline in the Hiawatha National Forest, an area celebrated for its concentrations of passage and breeding migrants. As Aldo Leopold pointed out some 50 years ago in one of his essays from Round River,"One of the fastest-shrinking categories of wilderness is coastlines. No single kind of wilderness is more intimately interwoven with history, and none nearer the point of complete disappearance."

RESEARCH ACTIVITY At the Lake Huron study site, we conducted mist-netting, insect sampling and focal observations of foraging birds.  We also located and monitored American Redstart nests, taking data on distance from the lakeshore, nest placement, clutch initiation date, and number and mass of eggs and nestlings.  We sampled vegetation and insect abundance within individual redstart territories.  Our situation is unique in that we were able to assess lakeshore habitat as both a stopover site for migrants, and a breeding site for those that stay. Click here for a complete table of all the birds captured at the Lake Huron study site over the years. Activity summary report for 1999 Activity summary report for 2000

ROB SMITH

Rob found that midges may be especially important during early spring, when the first migrants are beginning to arrive.  A number of bird species gain mass during this period; a time when few arthropods, outside of midges, are available.  Midges seem to feed both birds and spiders, and spiders and midges seem to feed birds during this early period. Thus, areas adjacent to northern Lake Huron provide important stopover habitat for spring migrating landbirds. Further, emergent aquatic insects are an important resource for landbirds migrating through Michigan's eastern Upper Peninsula.

Both arrival timing and arrival condition appeared to influence fitness in American Redstarts. Redstarts arrived in northern Michigan with fat stores, which may have been important as insurance against poor weather typical of early spring. Further, both arrival timing and arrival fat appeared to influence seasonal reproductive performance. Early females initiated clutches early and produced heavier nestlings. Early males appeared to settle on higher quality territories and hatched nestlings sooner than later arrivals. Finally, both females and males arriving with fat experienced gains in reproductive performance as shown by increased clutch size, egg volume and nestling mass. Rob's results have implications for understanding how events occurring during one phase of the annual cycle influence survival and reproductive performance in subsequent phases. Migrants that do well en route arrive at breeding grounds in superior condition, which may contribute to survival and reproductive performance.

The University of Southern Mississippi. Last modified: 24 February, 2007 . Questions and Comments?
URL: http://www.usm.edu/mbrg/LakeHuron.html
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