Throughout the river valley and along the creeks in the city many trees have been wrapped in metal wire to protect them from being chewed on and felled by beavers. Obviously not every tree can be protected like this so the city is focusing its effort on large and high-valued trees. One does not have to go far to see the effect energetic beavers can have on trees. The forest understory all over the city is littered with tree trunks having chewed on, stumps and felled tree trunks. Beavers require a large number of trees for food and for building dams. I have not seen any beaver dams in Edmonton so I assume that within city limits the beavers use the trees primarily as a food source. As soon as one goes outside the city, however, most lakes, ponds and creeks have lots of beaver dams in them. If the city beavers do not build dams, where do they live? This is a question I have not yet been able to find a satisfactory answer to.
It was a sunny late afternoon without a cloud in the sky. A gentle cold breeze made it feel colder than what it really was. It was silent down at the North Saskatchewan River except the rustle from the Quaking Aspen leafs. It was easy to spot the Aspen stand as these were the only trees with leaves left on them. As a matter of fact, while all the leaves were golden yellow on color it looked like none of them had been shed yet. Various species of Aspen are the most widely and commonly occurring three species in the northern part of North America.
From a distance The North Saskatchewan river looks like a quaint meandering water serpent. Once you get next to it, however, you quickly realize that the flow is fast and unrelenting. As a result, the river only freezes over completely when the temperature drops extremely low for long periods of time. As I went for walk along the river edge today I came across patches of thin ice along the shore. This first ice of the year is a sure sign of things to come.
I ook this picture along the Whitemud Ravine trail a few weeks back but it did not post it as identifying this organisms was a real head scratched. I erroneously assumed that it was a form of fungi as it had quite fleshly lobe-like leafs, not unlike some oyster mushrooms. This assumption is what made me hit a dead end when it came to identification. I stumbled across the picture by chance tonight and decided to take another stab at it. By now I had run out of “mushroom options” so I decided to broaden the set of possibilities. The only possibility, other than a fungus, would be a lichen. Loo and behold, it turned out to be a dog lichen. There are about 91 species of dog lichens world wide, all belonging to the genus Peltigera. These lichen are able to fix nitrogen directly from the atmosphere due to their coexistence with cyanobacteria. The fleshly leaf-like appendages are called foliose thalli. I have not been able to find out why they are referred to as dog lichens.
I took this picture about a week ago at Heritage Wetlands park. The colorful leaves did not last long. After a few windy days most trees are now completely leafless. The process of of shedding the leaves seasonally is called abscission and is under hormonal control in most plants. There are several advantages of loosing leaves seasonally, including conserving water and being able to better tolerate severe winter conditions. The obvious disadvantage is that deciduous plants need to spend resources on regrowing their leaves, a cost that evergreens do not have.
The petite Bufflehead was unphased by the strong breeze pushing it around on the choppy waters. Every now and then it did its funny looking dive where it sort of launches up and then dives down, similarly to how a person would dive into the water from the edge of a pool. Buffleheads can be found in the Edmonton area year round hanging out on any open water that they can find. My first Bufflehead was actually spotted in the middle of a deep freeze on January 20 in Genesee lake. It might be a small unassuming waterfowl but anyone that has the wits to survive the long Alberta winter deserves our respect.
The plan was to head out to the Heritage Wetlands park in Sherwood Park but half way there I realized that I would have to change my plans. The wind was picking up and with rain showers rolling in I had to make a quick decision if I should just scrap the plan and turn around or come up with a Plan B. I went with Plan B. As I was already in Sherwood Park I decided to make a quick visit to Emerald Lake and then decide where to go from there. To call Emerald Lake a lake is an overstatement. It is more of a storm water pond squeezed in between big box stores, a high school and busy roadways. Despite its unglamorous location the bird life can be surprisingly rich here. The main benefit on a day like this is that one can park in the parking lot of one of the big box stores only meters away from the edge of the lake. The wind blew off my cap several times and the trees were swaying in the strong breeze. A half dozen Canada Geese were swimming against the wind but did not seem to make any headway. Other than the geese, a few Golden Eye and Mallards it pond was, perhaps not surprisingly, abandoned.