by Christopher Dennison, Municipal Policy Intern
In the previous blog, we discussed the importance of shoreline land-use practices that maintain specific habitat characteristics (namely the planting and maintenance of native vegetation) to support waterbirds. But how can one ensure that the shoreline vegetation chosen will be appropriate for local species?
Indeed, the type of shoreline vegetation that is planted and/or maintained on a shoreline plays an important role in habitat selection and use in waterfowl. According to Dick, Smith, & Smart (2004):
“The benefits of aquatic vegetation for waterfowl may be dependent upon the species of vegetation present, with studies showing that migratory waterfowl appear to prefer native aquatic plants as opposed to exotic species […] Although reasons for this preference are not clear, native plants are held to be more nutritious than exotic species and are therefore more valuable to waterfowl” (p. 1).
Planting and management of shoreline habitats using native aquatic and/or moisture-tolerant species (and simultaneously removing invasives) can encourage use by waterfowl and other bird species for the nesting, foraging, and sheltering opportunities they provide. Other, hard engineering solutions to associated shoreline problems such as erosion, bank stability, and flooding should be considered for their ecological impact, as these techniques (e.g. shoreline hardening, retaining walls, etc.) often necessitate removal of riparian vegetation.
These points are clearly illustrated and supported across a number of published articles:
“[…] we found higher avian species richness at sites with intact understory vegetation than those without and increasing richness with canopy coverage. Aerial insect abundances, which were also higher at sites with an intact understory, may help explain bird distributions. Our results suggest that riparian understory landscaping at the scale of individual parcels can alter local bird communities” (Henning & Remsburg, 2009, p. 123).
“We recommend that continuous associations of mesic shrub vegetation be maintained or restored where possible because this vegetation structure is associated with avian abundance, species richness, riparian-associate bird species abundance, and landscape- level biological diversity” (Sanders & Edge, 1998, p. 461).
“Our results indicate that development at the shoreline scale has an important effect on waterbird community integrity, and that shoreline hardening and invasive Phragmites each have a negative effect on waterbirds using sub-estuarine systems (Prosser et al., 2018, p.S207).
Creating and maintaining effective shoreline ecosystems requires careful planning. The selection of plants, site-planning, and physical planting can be overwhelming. The results, however, are highly rewarding. Programs such as the Natural Edge and Love Your Lake can help property owners understand the specific requirements of their shoreline and can aid in the selection of shoreline plants and planting plans that allow for enjoyment of the water while also protecting waterbirds.
Human occupation and the well-being of waterbirds need not be mutually exclusive. Landowners who live or cottage on the shores of lakes, rivers, and other watercourses can take proactive steps to ensure that resident birds have access to nesting and foraging opportunities. Shoreline naturalization efforts that are well-planned, well- managed, and consider local conditions should be a goal for conservationists, cottagers, and hunters alike, as it promotes the conservation of several of our most beautiful and charismatic bird species while also supporting the health and wellbeing of the water itself.
Sources
Dick, G.O., Smith, J.K., & Smart, R.M. (2004). Migratory Waterfowl Habitat Selection in Relation to Aquatic Vegetation (ERDC/TN APCRP-EA-09). US Army Corps of Engineers. Retrieved from: https://apcrp.el.erdc.dren.mil/elpubs/pdf/apcea-09.pdf.
Henning, B.M. & Remsburg, A.J. (2009). Lakeshore Vegetation Effects on Avian and Anuran Populations. The American Midland Naturalist, 161(1), 123 – 133. https://www.jstor.org/stable/20491422.
Prosser, D.J., Nagel, J.L., Howlin, S., Marbán, P.R., Day, D.D., & Erwin, R.M. (2018). Effects of Local Shoreline and Subestuary Watershed Condition on Waterbird Community Integrity: Influences of Geospatial Scale and Season in the Chesapeake Bay. Estuaries and Coasts, 41(Suppl 1), S207 – S222. DOI 10.1007/s12237-017-0288-0.
Sanders, T.A. & Edge, W.D. (1998). Breeding Bird Community Composition in Relation to Riparian Vegetation Structure in the Western United States. The Journal of Wildlife Management, 62(2), 461 – 473. https://doi.org/10.2307/3802320.
This blog post is part of a series generously funded by Wildlife Habitat Canada’s Canadian Wildlife Habitat Conservation Stamp Program.