Yesterday evening, spurred by Doug Chickering's post on Tree Swallows on Plum Island,
I spent the evening on Plum watching the swallows gather to roost. There will be swarms of thousands of Tree Swallows along New Hampshire's seacoastand on Plum Island. They'll be swallowing high-lipid bayberries, [once ripe] to build theirfat stores for migration. Northern Bayberries contain carbohydrates and fat. The fat content of bayberries is nearly 50%; Arrowwood Viburnum fruit contains 41% fat, and Virginia Creeper fruit has 23% fat. These staging migrants will also consume lower energy fruits such as Pokeweed and Chokeberry. Bayberries are a small, spherical fruit with a waxy covering and are used for making fragrant candles. I know of a tradition that involved Bayberry Candles ~ burn one bayberry candle on Christmas Eve and another one on New Year's Eve, and that will bring luck and prosperity for the year ahead.
I hope these migrants have a peril-free journey and a favorable winter in South Carolina, Florida, along the Gulf Coast and proceeding as far south as Panama. Tree Swallows' primary food is insects, and they forage buggy, southern wetlands, sometimes in huge flocks. They consume dragonflies, damselflies, flies, ants, wasps, beetles, stoneflies, butterflies, mayflies, caddisflies, sawflies, bees, moths, spiders and mollusks. Some of these wetlands have been degraded and developed for housing, agricultural and industrial
land use. A change in water quality can also occur at development sites. Tree Swallows have been a periodic bird-strike problem at John F. Kennedy Airport in New York, creating runway closures, delaying flights and damaging aircraft. There were 65 Tree Swallows collected and examined at JFK Airport in October 2001. It was determined that the birds were attracted to the airport because of northern bayberry there.
Link to the article's abstract: