Arctic Challenge for Sustainability Project

ArCS Blog

Salluit Day 4: Large thalli (individuals) of rock tripe lichens

Looking at the map and aerial photo of Salluit, I noticed that there is a river surrounded by rocks, streaming almost along the center of the Salluit valley. Since rock tripe lichens grow anywhere on hard substrates, preferably in the presences of water and sunlight. Such sites as the rocky river banks could harbor lichens, and I hoped to find interesting lichen flora. One way to know is to see the site; to see is to believe.

Walking alongside the road, heading towards the stream, car drivers drove by and nodded or waved to in greeting. Salluit is a small community where all the residents tend to know each other. It is easy to spot visitors, and maybe there are used to having visitors around, because they were friendly to unfamiliar faces around.

Reaching the target rocky river bank, there were not much interesting sites along the river. However, from there I could see an ice-block (lingering snow) lying on the eastern slope, i.e., right bank, of the river. I headed towards south up the stream.

About 15m away from highway road, situated the stream. Low grassland covered flat area between rock boulders near the stream and the highway road. After several minutes observing the site, it was noted the lichen flora covering the rocks tended to be crustose flora closer to the stream, followed by foliose and frutiose lichens that shared space with bryophytes.

Rock tripe of the foliose lichens formed colonies in clusters at certain sites, while colonies at other sites were sparsely grown with larger individual thalli. In situ, I was inspired that it should be a perfect opportunity to compare variations of associated bacterial flora among individual thalli (intra-colony variations, or, inter-thallus variations), by collecting single but large thalli which would provide enough bulk DNA for microfloral analyses.

After collecting sufficient thalli, I headed toward a hill slop west of the Salluit valley. Rock boulders piled at the bottom of the slope. There, two interesting rock tripe colonies were found. One located along a steep slope, having larger thalli. The other rock tripe colonized a boulder at the bottom of the slope. Here, I collected additional “large” individual thalli, because then I could do comparison to see variations among individual rock tripe specimens of a same colony, i.e., INTRA-colony variations, as well as variations among the three groups of rock tripe colonies, i.e., INTER-colony variations.

Merry Sailonga Faluaburu


Ice-block (lingering snow) lying on the river bank


Collecting lichens on a rocky slope