As I was saying in yesterday’s post, the chickadees at the Grey Nuns Spruce Woodlot were out in full force. Accosting us as soon as we arrived. If you stretched out your hand, a chickadee would immediately land on it and start to look for treats, pecking your fingers with its tiny bill. As soon as it realized that there were no treats to be had it would take off, only to immediately be replace by another one. It was a whirlwind of chickadees and, as usual, I identified them all as Black-capped Chickadees.., that was, until I was going through the pictures the next day. I realized that one of the chickadees did not look like the others. Instead of a black capped head it had a brown head with more brown throughout its body. In the freeze frame picture it is easy to see (if you pay attention) that this is a Boreal Chickadee. Boreal Chickadees are typically solidly outnumbered by the Black-capped Chickadees and I a rarely lucky enough to spot one. This is the first picture I have taken of a Boreal Chickadee. It’s a bit ironic that I did not realize what I had taken a picture of until the next day.
We went to the Grey Nuns Spruce Woodlot today. This patch of forest is a remnant of a much larger forest that existed at the time of settlement of the St. Albert area over 170 years ago. It is an old-growth forest that is squeezed in between the busy Ray Gibbon Drive, the Joy Centre and sprawling sub-division developments. The forest is just over 40 hectares in size and contains a diversity of tree covered, shrub and grassland areas. Among birders the area is perhaps best known for its large number of Snowy Owls during the winter. It was here that I spotted my first Snowy Owl last winter. During our visit today we went on the narrow trails winding through the forest. As soon as we arrived we were accosted by a band of energetic and chubby Black-capped Chickadees that required us to appease them with food. They simply did not take a no for an answer and continued to follow us through the forest. I suspect that they probably are used to being fed by humans, which was further corroborated when we came across an old dilapidated feeder hanging just off the trail where the chickadees had spray-pained “FEED US PLEASE”. We did not bring any food for the feathered denizens of the forest this time, but clearly next time we will have to make up for this.
I came across a Northern Flicker today sitting on a trunk working on its nest. Earlier during the summer I saw a flicker at the same cavity, so I assume it could be the same individual. There are two quite different-looking forms of the species, the Yellow-shafted Flicker in the east and north, and Red-shafted Flicker in the west. This particular individual had the red crescent on its nape distinct of the Yellow-shafted Northern Flicker. The dark “mustache stripe” by the beak indicates that it is a male.
A meandering creek (or river) is a a creek characterized by a series of regular sinuous curves, bends, loops, turns or windings in the watercourse. A meander is produced by the river as it erodes the sediments of an outer (or concave) bank and deposits this and other sediments downstream on an inner (or convex) bank. The concave side of a meander is often referred to as a cut bank and the convex side as a point bank. Over time the result is the formation of a meandering course as the channel migrates back and fort across the direction of the floodplain. There is a whole lot of physics and math behind the formation, dynamics, size and shape of the meanders. The Whitemud Creek is meandering its way through the Whitemud Ravine and the erosion that takes place during this process is very noticeable on a seasonal basis. Particularly the cut banks seem to be advancing at a very fast pace with lots of trees succumbing and falling into the river as sections of the bank collapse into the creek. I am sure the busy work of beavers – i.e. removing trees – accelerates this erosion process. We humans are not, however, idle. In an effort to control the erosion and the ever-shifting course of the creek large swats of cut banks are covered in rocks, mesh and planted with fast growing plants. In today’s picture you can see a cut bank covered in sizable rocks in an effort to reduce the erosion and stabilize the bank. It seems, however, that most of these efforts only postpone the inevitable and it seems to be a loosing battle. The combined force of the beavers and the flow of the water is mighty.
So I found another beaver dam down at the Whitemud Creek. That makes it two dams that have sprung up in the last month. This one is tucked away in a secluded part of the creek and is smaller than the first one. It is large enough though to dam up the water upstream, allowing only a small stream to flow over the crest. It is made up of smaller branches and twigs, but is remarkably efficient in blocking the flow of the water. It is difficult to imagine how one would successfully build a dam made up of branches in a flowing creek. There clearly must be some beaver science going on here. When people refer to beavers as engineers, they go that part right.
The traditional name of Edmonton is Amiskwaciy Waskahikan, meaning Beaver Hills House. This place was the traditional meeting ground for many indigenous communities, including the Cree, Saulteaux, Nakota Sioux, Blackfoot and the Métis Peoples. Once one becomes more familiar with the natural history of Edmonton and its surrounding area, the choice of the name Beaver Hills House by the indigenous communities becomes apparent. Beaver houses, or lodges, are never far away. Every lake and pond outside of Edmonton seems to have at least one beaver lodge built in it. The Whitemud Creek is different tough. While there are certainly beavers in the creek, there are no beaver dams or lodges, or at least I have not been able to find them. I always though that one reason for this would be that it is a creek where the water is in constant motion. That is until I found beaver dams and lodges in a remote location of the North Saskatchewan river. So much for that theory. After spending lots of time at the creek it has become evident that the quaint creek is a battle ground between industrious beavers and equally industrious humans. The beavers are trying to go about their lives, which obviously includes a domicile, food and raising a family, while the humans are doing everything they can to maintain the ravine as a safe recreational area. Much could be said about the back and forth battle between the beavers and humans (see for example yesterday’s post), but it is now becoming evident that the Whitemud Creek beavers do indeed build dams, and quite possible lodges as well, but the humans are removing them. The other day I came across a sizable dam entirely obstructing the creek that must have been erected over the last few weeks. It will be interesting to see how long it will take before the crews move in and remove it. I will be doing more regular visits to the creek to monitor the situation.
There is a rather unique tree down in the Whitemud Ravine. It is large and tall and half way up its trunk there is a l large cavity that has been used as a nesting cavity by Great Horned Owls for a number of years, most recently last spring. The other day I noticed that the base of the trunk had been wrapped in wired mesh. With the beavers coming back with a vengeance over the last few weeks it is hardly surprising that the city has tried to protect the tree. The City of Edmonton’s official policy on reducing beaver damage is to protect “high value trees” using metal mesh around the base of the trunk. As this is the only know Great Horned Owl nest it this part of the ravine this is definitely a high-value tree (see post 32). At this time of the year, the owls are nowhere to be see. One can only hope that the will be back next spring with a new batch of adorable owlets.