All summer long, from April until October, I look up at the St. Albert sky and see flock after flock of white birds with long pointed wings and black heads flying to the west. Every night they can be heard squawking and seen zipping about in a playful manner as they make their way to Big Lake in large ‘V’s. These birds are Franklin’s gulls, gulls of the Canadian Prairies breeding mainly in Alberta, Saskatchewan, and Manitoba but as far south as Montana, North and South Dakota, and Minnesota.¹ They spend their winters in Chili and Peru before making the amazing journey of more than 8,000 km back to their breeding grounds.²
Franklin's gulls are truly beautiful birds. The size of crows, they have grey backs, white underparts, and black heads with white eye rings. They have red bills with black on the tip and red legs. When the birds first arrive in the Canadian Prairies, you may notice a pink colour on white feathers of the birds’ underparts. This colour fades away within a couple of weeks of arriving but the source of this pink hue is fascinating. The birds have a large amount of the carotenoid, astaxanthin in their feathers, the same carotenoid, or organic pigment, that is found in the feathers of flamingos. This colourant is believed to come from the bird’s diet.³ In the summer, Franklin’s gulls feed on mostly aquatic insects, grasshoppers, and earthworms but on their wintering grounds they feed mainly on small fish and crustaceans.
During their time on their breeding range, Franklin’s gulls nest in huge colonies numbering into the thousands. Their floating nests are built on shallow areas of knee-deep to neck-deep water with a mat of vegetation on the water’s surface anchored to rooted vegetation such as cattails and bulrushes.⁴ The reason these beautiful gulls can be seen throughout the Edmonton area playfully flying towards the west is the presence of a huge colony on the west end of Big Lake. In the 1980s, estimates were as high as 3,000 nests in this colony which equates to more than 1% of the entire world’s population. In 1999 a provincial biologist observed that the lake had no birds at the breeding colony⁵ and population numbers have definitely fluctuated over the years with the colony coming and going depending on conditions. Unfortunately there is not a lot of recent data on the colony due to it being difficult to access to properly study.
Big Lake is a large, shallow lake on the western edge of St. Albert. The entire lake is protected as a Provincial Park — Lois Hole Centennial Provincial Park — and is designated as a globally significant Important Bird and Biodiversity Area (IBA). Even with the IBA designation and protections of being a Provincial Park, this lake still faces threats that have the potential to impact Franklin’s gull populations. Franklin’s gulls are very sensitive to changes in their nesting habitat and will abandon or change the location of a colony in response to changes in water expanse, water depth, density of vegetation, and size of open-water areas.⁶ With the Big Lake being such an important area for the birds, it is critical that we protect the habitat; as the habitat of the lake degrades, the suitability as a nesting area is reduced. The main threats that the Franklin’s gulls of Big Lake face are threats to water quality, water levels, and threats to the area’s biodiversity.
Water Quality
Big Lake is a part of the Sturgeon River subwatershed and fed by many streams in the system. Fertilizers, nitrates and pesticides enter the water system through sewage lagoons, agriculture, and various golf courses both local and upstream.⁷ This has a large negative effect on the water quality of the lake.
Water Levels
The water levels of Big Lake fluctuate naturally but anthropogenic factors can increase this fluctuation making the area a less desirable nesting area for Franklin’s gulls. With development on the floodplain immediately upstream of the lake, flooding has and will continue to increase meaning a stormwater management plan is essential where any development has occurred.⁸ As well, any further development needs to be stopped on the floodplain to protect and preserve this crucial area.
Biodiversity
A third impact on Big Lake and, in turn, on the gulls is threats to the biodiversity of the region’s flora and fauna. One of these such threats is the introduction of invasive plants. The main concern for this area is purple loosestrife.⁹ This plant can take a foothold and have large negative impacts on a wetland ecosystem. Keeping this species in check and not introducing it further into the area’s yards and gardens is an important step to protecting the ecosystem. Another stressor to the biodiversity of the area is pollution in the form of waste, light, air, and noise. Due to the proximity of this area to the city of St. Albert all of these come into play. Simple steps like turning off outdoor lights and avoiding the use of single-use plastics bags can help as well as bigger steps such as the local municipalities controlling the noise from the nearby highways and development and avoiding the use of chemicals for pest control and deicing roads.
Big Lake is an extraordinary place and the Franklin’s gulls that inhabit it are equally remarkable. Both the area and the birds, however, are susceptible to anthropogenic threats but if we work to protect this area, the squawks of the Franklin’s gulls will continue to be heard for generations to come as they zip above us in the St. Albert skies.
1. Burger, J. and M. Gochfeld (2020). Franklin's Gull (Leucophaeus pipixcan), version 1.0. In Birds of the World (A. F. Poole, Editor). Cornell Lab of Ornithology, Ithaca, NY, USA. https://doi.org/10.2173/bow.fragul.01
2. Paulson, D.(2012). Franklin’s gull —the half-time seagull. Birdnote. Retrieved from https://www.birdnote.org/show/franklins-gull-half-time-seagull
3. McGraw, K. J., & Hardy, L. S. (2006). Astaxanthin is responsible for the pink plumage flush in Franklin's and Ring‐billed gulls. Journal of Field Ornithology, 77(1), 29-33.
4. Burger, J. and M. Gochfeld (2020). Franklin's Gull (Leucophaeus pipixcan), version 1.0. In Birds of the World (A. F. Poole, Editor). Cornell Lab of Ornithology, Ithaca, NY, USA. https://doi.org/10.2173/bow.fragul.01
5. Lane, B. (2000). Big Lake Important Bird Area Conservation Plan.
6. Federation of Alberta Naturalists. (2007). The Atlas of breeding birds of Alberta: a second look. Nature Alberta.
7. Alberta Parks. (2019). Lois Hole Centennial Provincial Park management plan. Alberta Government.
8. Big Lake Basin Task Force. (2004). Big Lake stormwater management plan. St. Albert Government.
9. Alberta Parks. (2019). Lois Hole Centennial Provincial Park management plan. Alberta Government.
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