Birds and Climate: Swans Move North
The climate is changing, which makes future habitat ranges uncertain. This could be a big problem for many species as they fight to find suitable places to survive. The National Audubon Society recently released The Audubon Birds and Climate Report. This report describes the potential future for the climate range of 588 North American birds.
What does this mean for the future of Canadian birds?
In this series we will explore how these predictions will impact Canadian birds; from our backyard favourites to little known treasures, and Canadian icons.
This week, we will explore a bird with regal symbolism; the swan.
Swans are one of the most iconic birds known all around the world always depicted as graceful, beautiful, and pure creatures. Swans were and still are used as a symbol of royalty. One castle in Germany goes so far as to have swan decorations in almost every room! This is the same castle which inspired Walt Disney’s iconic castle.
In Canada, there are three regularly occurring swan species: the Tundra, the Trumpeter, and the Mute Swan. We will explore how predicted climate range shifts could affect 2 of these 3 species in this post.
The Trumpeter Swan
The Trumpeter Swan spends the summer in the Yukon, British Columbia, and Alaska and winters along the western North American coast with an isolated population around the Great Lakes area.
During early European settlement, there is evidence that a Great Lakes population of the Trumpeter Swan was eliminated by hunting. With focused conservation efforts this species was successfully reintroduced. Climate range shifts are predicted to take place in the near future, these populations could soon be under threat once again.
Over the next 60 years, The National Audubon Society predicts that the Trumpeter Swan could lose the entirety of its North American summer climate range and nearly half of its winter range. If these changes occur as predicted, the Trumpeter Swan will be pushed almost completely out of the US and into central Canada during the winter. During the summer the Trumpeter Swan will be forced even further north.
The Tundra Swan
The Tundra Swan breeding ground, much like the name suggests, is much farther north than the Trumpeter Swan, breeding in colder environments like the Northwest Territories and Nunavut. However, the Tundra Swan crosses paths with the Trumpeter Swan when it migrates down to the southern states for winter.
If current climate trends continue, by 2080 the St. Lawrence Seaway and Great Lakes area will be at ideal temperature for this bird. However, temperature is only one of many factors that must be taken into consideration when birds look for suitable habitat. Other important factors include food availability, environmental conditions, and the presence of predators as well as human influences such as cities, roads, and industries. Although the St. Lawrence Seaway and Great Lakes region will provide ideal temperatures, this is also the most heavily populated region of Canada, so finding sufficient habitat may be the greatest challenge.
While some Canadians will have the opportunity to enjoy observing these beautiful birds as more of them move into our populated areas, their breeding environment could decrease by as much as 31%. This decrease of a full third of their breeding environment could be significant enough to completely isolate the Tundra Swan to the northern islands of Nunavut and the Northwest Territories.
On the Audubon website, there is a summary of each of the birds projected shifts in the form of a map of North America and Venn Diagrams. For a guide on how to interpret these diagrams, please click here. To find information on a specific bird, please visit climate.audubon.org