Green-scaled willow (Salix chlorolepis) COSEWIC assessment and status report: chapter 7
Population Sizes and Trends
The 2004 inventory was carried out in 10 glacial cirques in response to the lack of data on certain sectors of Mount Albert and the potential of discovering new occurrences of green-scaled willow. It provided data on the abundance and preferred habitat of this species. The positions of most specimens were recorded using GPS in order to determine their distribution. Approximately 45 hours of fieldwork were carried out on Mount Albert to locate new occurrences.
An estimated 300 individuals occur on Mount Albert. Each occurrence typically comprises only one or two individuals, but some sites consist of five or six. According to CDPNQ, one site in the glacial cirque of the westernmost part of Vallée du Diable comprises approximately 200 individuals. At that location, 60 individuals were counted in the 2004 inventory by following a fixed elevation. No individuals were counted at lower elevations.
Not all of the glacial cirques of Mount Albert have been explored. Figure 5 indicates the recorded sightings that have been reported (some overlapping is present and does not show up at the map scale provided). These sightings have been grouped into four discrete populations (or Element Occurrences) based on a minimum separation of about 1 km between the closest sightings in adjacent populations. The southernmost sighting in population 3 could possibly be considered as part of a separate population from the three northern sightings, but is here maintained as part of population 3. The writer recognized the fact that the 3-dimensional distances are somewhat greater between sightings than can be calculated on a 2-dimensional map. The total number of individuals on Mount Albert, even with an extremely optimistic extrapolation, would likely not exceed 1,000 plants.
Since it is a perennial, green-scaled willow does not appear to be affected by changes in population size or density. A number of botanists have tried to locate it, but have been thwarted by bad luck. For example, it took until 1981 to find a male specimen, whereas several were observed in the 2004 inventory. The CDPNQ knew of the occurrence of the green-scaled willow in four glacial cirques in Mount Albert’s Vallée du Diable in 1994. Following the 2004 summer inventory, the number of sites of this population is now 10 and the green-scaled willow has been found at several locations outside Vallée du Diable, including four glacial cirques on the south side of southern Mount Albert and in the side of the glacial cirque of Plaqué Malade Lake. Green-scaled willow had already been reported on the plateau of Mount Albert, but despite several kilometres of transects between northern and southern Mount Albert, none were found in the 2004 inventory (Figure 5).
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