What do migrating birds mean to Lake Champlain? And what does a healthy lake mean to birds?
On a sunny spring day driving on the highway by the Winooski River, my friend points out in joy towards the telephone lines, “Is that an osprey?” Without hesitating, my other friend swerves over to the edge while pulling our windows down and binoculars up. There it was, a large black and brown speckled osprey resting on its large nest. Its eyes widened as we watched and photographed it in awe. Ospreys are such talented nest builders many end up reusing their massive stick nests from previous years strategically located near bodies of water. We welcomed the bird back to the Champlain Basin, and the bird welcomed us to spring.
The osprey is one of the many migratory waterbird species making their return to our watersheds up north from their winter in Central or South America. You will often find the distinctive fish-hawk species hovering over water searching for fish they grab by spearing them with their talons. Ospreys are found near water with large numbers of fish, ranging from coastal estuaries, salt marshes, large lakes, reservoirs, and rivers. Their survival relies on the aquatic food chain determined by the health of waterways.
Excess phosphorus and other contaminants impact the waterways that migratory waterfowl such as ospreys use for hunting fish. These contaminants paired with warming temperatures and frequent intense rainfall result in the rise of algal blooms which harm the aquatic life these birds depend on. With recent water pollution and the effects of climate change, there has been a decline of 24 bird species in New York, Vermont and Québec. In the state of Vermont, species including the great blue heron, American black duck and red-shouldered hawk are listed by the state as “greatest conservation need.”
As Vermont transitions to summer, Lake Champlain’s riparian forest buffers play a critical role in the lifecycle of a variety of birds. The USDA National Agroforestry Center defines riparian zones as “natural or re-established woodlands next to streams, lakes and wetlands.” Each bird species has specific requirements for these riparian habitats depending on whether they are camouflaging, nesting, or sourcing food. Bald eagles nest in forested riparian areas while Louisiana waterthrush use the banks of the river for nests. While bank swallows and belted kingfishers nest on the edge of the soft banks, they use the rivers, lakes, or streams to forage.
Birds can play a pivotal role in the success of habitat restoration by acting as seed dispersers and controlling pests in native planting projects. They can also serve as bio-indicators of changes in water quality, riparian conditions, and evaluating restoration outcomes. Riparian zone restoration is also important for water quality and human health since riparian forests assist in streambank stabilization by filtering nutrients, sediment, and pesticides from nearby areas before they enter our waterways. They also help reduce flood damage by reducing floodwater velocity and blocking stream debris from entering agricultural and residential areas with woody buffers.
The high diversity of bird species along our waterways highlights the important role of water and riparian zones in supporting all kinds of life. To continue learning about the connection between birds and water, read Riparian restoration with birds in mind, a resource developed by Cassie Wolfanger in her position with Audubon and Lake Champlain Sea Grant. If you’re interested in learning more about riparian restoration and management, check out the Lake Champlain Sea Grant’s Watershed Forestry Partnership. This partnership works with stakeholders across Vermont and New York to promote riparian forest development and management for water quality in the Lake Champlain basin.
Gabriella Marchesani is a senior at the University of Vermont studying Environmental Studies. This semester she is working with Lake Champlain Sea Grant to connect current happenings to the ongoing work of Lake Champlain Sea Grant to develop and share science-based knowledge to benefit the environment and economies of the Lake Champlain basin.