Distribution and assessment of the conservation status of Erioderma pedicellatum in Asia

Abstract

The first detailed survey is presented of a recently discovered population of Erioderma pedicellatum, a globally rare lichen, in the primeval spruce forests of the Kamchatka Peninsula, Russia. Three subpopulations are described, located in the Levaya Schapina River basin, in the Kimitina River basin, and on the slopes of the extinct volcano, Nikolka. In total, we observed 1894 thalli on 167 Yezo spruce trunks. In Kamchatka, E. pedicellatum occurs exclusively on bark-covered spruce twigs of mainly young and dwarf-stressed older trees. We discovered a high number of juvenile thalli, which suggests that this population is reproducing. However, its habitat is declining because spruce forests in the region are the target of industrial clear-cutting and there is a high incidence of forest fires. Over the next 60 years, which corresponds to three generations of E. pedicellatum, we infer that continued habitat loss will induce a 48% decline in these lichen populations. As a result of our analyses, the Asian population is classified as ‘Vulnerable’, based on IUCN Red List criteria.

The globally threatened epiphytic cyanolichenErioderma pedicellatumdepends on a rare combination of habitat factors

“…2013; Holien 2015; Tagirdzhanova et al . 2019). The lower part of the canyon represents a unique environment with epiphytes and microclimate resembling those in open patches of the Norwegian boreal rainforest (Holien & Tønsberg 1996), differing from the surrounding dry low-productive pine forest.…”

“…2013 b ; Tagirdzhanova et al . 2019) and air pollution (Richardson & Cameron 2004), but wildfire (Tagirdzhanova et al . 2019) and gastropod grazing (Cameron 2009) are important local threats.…”

“…2019) and air pollution (Richardson & Cameron 2004), but wildfire (Tagirdzhanova et al . 2019) and gastropod grazing (Cameron 2009) are important local threats. After new populations in Alaska and Kamchatka were discovered, the situation improved, but was still considered critical (Cameron et al .…”

“…2013; Holien 2015; Tagirdzhanova et al . 2019). After being considered extinct for < 50 years in Europe, two thalli were found in the Norwegian boreal rainforest (Tønsberg et al .…”

Substratum dynamics over time could influence the rarity of tree-dwelling cyanolichens

“…Another study successfully aged host trees and found that the number of thalli per tree peaked on 80-year-old trees (Tagirdzhanova et al . 2019), which is beyond the maximum average age of balsam fir in our study region. The patterns between boreal felt lichen host tree age, size and condition in these wetter areas is not well known.…”