Weekend Rains Wash Tree Debris Into Sooke River Estuary

Although everything is calm on the Sooke River estuary today, the weekend was a different story. A record rainfall flooded the Victoria region with a deluge that put many local roads under water. Another winter day in the rain forest.

When we get these strong winter storms the Sooke River becomes Mr. Hyde to the drought seasons calm, well-mannered Dr. Jekyll. Water levels rise quickly in a big storm, and erosion muddies the normally clear water. And as the river crashes down through the forest covered hills it washes out all kinds of debris that eventually ends up in the estuary and harbour.

On the weekend the soupy water was moving fast and carrying everything from silt to single trees. Severe winter storms such as the one we had on the weekend are an exciting time to be in the rain forest, if you don't have to drive Highway 14.

All is calm today, but the new wildlife trees are evidence of the high waters

It is always fun to see the new tree debris added to the estuary. Some will wash away with the next high tide, and other large debris may be around for years or decades. However long they stay, they will add diversity to the estuary. The trees thrive with life, although not their own.

The estuary wildlife trees host an abundance of life, the most obvious of which are the birds. Eagles frequently use their favourite trees to perch on or to eat a meal of duck or sea gull. Cormorants sit on logs facing the sun with wings spread wide. Gulls like to captain logs as they float around with the currents and tides.

River otters are also regular users of wildlife trees for playing on, slumping across and sleeping in a sunbeam, or for holding a crunchy crab lunch.

Eagles hanging out on a Western red-cedar wildlife tree in the Sooke River estuary

 It is amazing to see the power of the river to deposit huge trees into Sooke Harbour during winter storms. During dry summers it might be hard to float a small branch down the meager trickle. In winter it turns into a white foam raging torrent.

The trees that the high water brings continue to add to the diversity of the coastal rain forest. In addition to the structure that they add, nutrients that the salmon brought into the forest from the sea are now being returned to the sea.

Bald Eagles and Big Trees

You need big trees for birds this large

Bald eagles are forest creatures requiring large territories that contain big trees close to water for nesting and perching. Only large, old trees have the strength, height, and branching structure that eagles require. The loss of such trees has been partly responsible for their drastic drop in numbers. Eagles need big trees.

The nest of a bald eagle is known as an Eyrie. It is one of the largest bird nests in the world, and can weigh as much as 2 tons. The nest consists of sticks and branches wedged together to make a large mass of material. Only sturdy, old trees can support these heavy structures.

Bald eagles use the same nests every breeding season. They keep adding new materials year after year. They line their Eyries with twigs, moss, feathers, and grass. A new nest is typically 2 feet deep and 5 feet wide but can grow enormously over the years. If a nest is destroyed for any reason, then the bald eagles usually remake their nest in close by areas. Eagle pairs will often use the same nest site for their entire breeding life.

Eagles also use large trees that emerge from the surrounding canopy to perch on. From these emergent trees the eagle can survey their territory for prey and other eagles.

Bald eagle nesting territory

Some of the trees surrounding Sooke Harbour are large enough to support massive eagle nests. A couple of years ago the largest, tallest tree in a forested area in my neighbourhood was toppled in a storm. For many years this tree provided the scaffolding for a giant nest that a pair of eagles had used faithfully season after season. I watched several baby eagles fledge at that site, and was sad to see the tree laying on the ground when I went over to investigate. The ton of material forming the nest may have been responsible for the tree toppling over.

One year I watched a baby eagle from this nest learning to fly along the edge of the forest. It flew to a tree and landed on a branch. All of a sudden the young, inexperienced eagle lost its grip and swung upside down on the branch with its wings spread wide. It stayed hanging like this for almost a minute, not seeming to know what to do next. Then it released its grip, took flight again, and landed in a more upright position. Kids do the funniest things.

Local eagles love this big tree

After the neighbourhood nest was lost the eagle pair relocated to another large tree within their territory. Close to the new nest site is a very tall tree that was used this year by a fledgling eagle learning to fly. The eaglet, perching on a sturdy branch would spread its wings, catch the wind and hop up and down in brief mini-flights.

Most eagle nest trees on the east coast of Vancouver Island (81%+) are veteran Douglas-firs over 150 years of age, usually found within a kilometre of the shoreline.

99% of old growth Douglas-fir forests on southeast Vancouver Island have been logged, and a great deal has been developed. Until recently, enough small stands of old growth, or lone veteran trees amongst smaller second growth, have remained to support a sizable nesting eagle population. However, continued development and logging of lands have caused the loss of nest trees, threatening the long-term maintenance of their numbers. Eagles need big trees.

In British Columbia landowners having eagle nests on their property are required by law to develop a management plan showing how the nest tree is to be preserved.