Calicioid diversity in humid inland British Columbia may increase into the 5th century after stand initiation

Abstract

Maintenance of biodiversity in managed forested landscapes requires detailed knowledge of the ecological requirements of specialist organisms linked to key microhabitats. Here we examine the relationship of 37 lichenized and unlichenized epiphytic calicioid species to stand age and substratum type in seven pairs of mid-seral (70–165 y) and old (220–470 y) forest stands in humid east-central British Columbia. Based on our inventory of eight host tree species, total calicioid diversity and mean species richness are highest in old stands, with 12 species not detected and nine additional species much less frequent in mid-seral stands.Thuja plicatasupports by far the highest level of total calicioid diversity, with 31 of 37 species; mostly associated with very old trees. Owing primarily to the late recruitment of lignicolous calicioids, stand-level calicioid richness continues to increase into the 5th century after stand initiation. Our study thus has two major findings pertinent to the maintenance of forest biodiversity in managed forests: first, stand-level calicioid richness increases slightly for at least three centuries past the acquisition of old-growth status; second, remnant trees and snags carried forward into mid-seral, regenerating stands enhance overall calicioid species richness. These results suggest that very old old-growth (= ‘antique’) forests might play an important role in the long-term maintenance of calicioid species richness, further suggesting that the standard practice of lumping all forests above a set age into a single old-growth category is not ecologically tenable for all taxonomic groups.

Tree-Related Microhabitats Are Promising Yet Underused Tools for Biodiversity and Nature Conservation: A Systematic Review for International Perspectives

“…Many North American studies have already identified the microhabitats of specific taxa, for example lichens and fungi (e.g., Goward and Arsenault, 2018), arthropods (e.g., Schowalter, 2017), or birds and mammals (e.g., Drapeau et al, 2009). Similarly, tree defect surveys are regularly used in certain regions of North America to describe forest stand quality and partially capture the TreM concept (Martin and Raymond, 2019).…”

DNA barcoding aids in generating a preliminary checklist of the lichens and allied fungi of Calvert Island, British Columbia: Results from the 2018 Hakai Terrestrial BioBlitz

“…In the index, the presence of 16 or more calicioid species is considered an indication of an “ancient” forest with a long history of continuity – and we found 16 calicioid species on Calvert Island. Goward and Arsenault (2018) also show that calicioid numbers positively correspond with stand age in the humid inland forests of British Columbia. We found Pseudocyphellaria rainierensis on Calvert Island as well, which is known to be restricted to old-growth forests in the British Columbia coastal region ( COSEWIC 2010 , Environment and Climate Change Canada 2017 ).…”

“… Pettersson et al (1995) , Hansell (1996) , Webber et al (2022) , Miranda-González et al (2023) ). Moreover, lichen communities are used as indicators of atmospheric pollution ( Hawksworth and Rose 1970 , Richardson 1988 , McMullin et al 2016 , McMullin et al 2017a ), ecological continuity ( Tibell 1992 , Selva 2003 , Goward and Arsenault 2018 , Bell-Doyon et al 2021 , Wiersma and McMullin 2022 ) and biodiversity conservation value ( Goward 1994 , Malíček et al 2019 , Miller et al 2020 ). Lichens are also numerous; in Canada and the United States alone, there are 5823 species in 805 genera, including allied fungi ( Esslinger 2021 ).…”

Why is the rainforest lichen Methuselah’s beard (Usnea longissima) so rare in British Columbia’s inland temperate rainforest?

“…The historical explanation pertains to the relatively recent development of the Caribou rainforest ecosystems. Palynological evidence suggests that Western Red-cedar, a tree whose presence can promote establishment of many old growth lichens (Goward & Arsenault 2018), entered the Caribou rainforest about 6,000 years ago in the extreme south and only 2,000 years ago farther north (Gavin et al 2009). This timeline is relevant insofar as dispersal in U.…”