Okanagan Similkameen Conservation Alliance  tree
While all trees might be used by wildlife, not all trees are “wildlife trees.” A wildlife tree is a standing tree (alive or dead) in a decaying state that provides valuable habitat for many species. In B.C., the wildlife trees become prime real estate for many species of birds, particularly woodpeckers.

What Makes a Tree a Wildlife Tree?

A wildlife tree is any standing dead of living tree with special characteristics that provide important habitat for wildlife. These characteristics include large (sometimes hollow) trunks, large branches, deformed and broken tops, internal decay and sloughing or loose bark. Wildlife trees are important because over ninety different plants and animals in British Columbia’s forests need them for habitat. In the South Okanagan-Similkameen, some examples of tree species that commonly make high value wildlife trees are Ponderosa Pine, Douglas-fir, Western Larch, Black Cottonwood and Trembling Aspen.

How are Wildlife Trees Created?

Trees do not simply die of old age, but are killed by insect attack, disease, fire, lightning, lack of light or poor growing conditions. The decay of standing live of dead trees may start from the centre of the tree or from the outside, in the bark. These different types of decay can provide different types of habitat for wildlife. Trees rotting in the centre may be hollowed out and used for nesting while rotting bark might provide food.

What are the Threats to Wildlife Trees?

Wildlife trees are becoming increasingly scarce as old forests are harvested for forest products or lands are cleared for agriculture and other types of development. In settled areas, wildlife trees are commonly felled because of liability concerns and a general lack of awareness that these trees have significant wildlife values.

Who Uses Wildlife Trees?

Animals that depend on wildlife trees for habitat may be divided into three groups: primary cavity excavators, secondary cavity users and open nesters. Primary cavity excavators, such as woodpeckers and some species of nuthatches and chickadees excavate their own cavities. Secondary cavity users are unable to excavate their own cavities and rely on cavities excavated by primary cavity excavators and on naturally occurring cavities. This group includes some of the owls, swallows, bluebirds and ducks, as well as mammals like marten, raccoons, squirrels and black bear. Open nesters are birds that build large, heavy nests on the tops or in the crooks of large wildlife trees. Ideal nesting conditions for birds like the Great Blue Heron, Osprey, Bald Eagle and large hawks and owls are created when trees are topped or broken from strong winds or from lightning strikes.

What are Woodpeckers?

Woodpeckers are birds belonging to the order known as Piciformes, in the family Picidae. Members of this family are found worldwide, except for Australia and New Zealand, Madagascar and the extreme polar regions. Most species live in forests or woodland habitats, although a few species are known to live in treeless areas such as rocky hillsides and deserts. Although male and female woodpeckers tend to look alike, males commonly have more prominent red or yellow head markings than females. Woodpeckers have strong bills for drilling and drumming on trees and long sticky tongues for extracting food. The bill’s chisel-like tip is kept sharp by the pecking action in birds that regularly use it on wood.

Woodpeckers possess zygodactyl feet which consist of four toes, the first and the fourth facing frontward and the second and third facing back. This type of foot arrangement is good for grasping the limbs and trunks of trees. Members of this family can walk vertically up a tree trunk, which is beneficial for activities such as foraging for food or nest excavation. Woodpeckers are referred to as “keystone” species because of their role in creating habitat suitable for other forest wildlife, namely the many secondary cavity users.

Who are the Woodpeckers of the South Okanagan Similkameen?

What you can do to protect wildlife trees and the woodpeckers and other wildlife that depend on them

  • Allow wildlife trees to remain on your property unless they pose a safety threat. Remove only unsafe branches and tops with the help of a professional arborist or tree service.
  • Consider placing stewardship conservation agreements or covenants on your land to protect wildlife tree patches or important wildlife habitat.
  • Do not use wildlife trees for firewood.
  • Encourage your local government to incorporate wildlife tree protection into bylaws, zoning and Official Community Plans.
  • Learn more about wildlife trees. Check out the WiTS website.
  • Become involved with the Wildlife Tree Stewardship Program (WiTS). Help identify wildlife trees and monitor nests in the Okanagan Similkameen. Contact witsos@shaw.ca for more information.
  • Report sightings of these rare woodpeckers to Bird Studies Canada (250-496-4049) or Partners in Flight BC/Yukon (250-490-8286).

Click here to download a PDF version of this article.

Back to Spotlight on Species and Habitats