How generalist are these forest specialists? What Sweden’s avian indicators indicate

Abstract

Monitoring of forest biodiversity and habitats is an important part of forest conservation, but due to the impossible task of monitoring all species, indicator species are frequently used. However, reliance on an incorrect indicator of valuable habitat can reduce the efficiency of conservation efforts. Birds are often used as indicators as they are charismatic, relatively easy to survey, and because we often have knowledge of their habitat and resource requirements. In the Swedish government's environmental quality goals, there are a number of bird species identified as being associated with 'older' and 'high natural value' forests. Here we evaluate the occurrence of four of these indicator species using data from 91 production forest stands and 10 forest reserves in southern Sweden. The bird species assessed are willow tit Poecile montanus, coal tit Periparus ater, European crested tit Lophophanes cristatus and Eurasian treecreeper Certhia familiaris. For the production stands assessed, these indicator species exhibited no significant preferences regarding forest composition and structure, indicating a wider range of habitat associations than expected. These species frequently showed territorial behavior in forest stands <60 and even 40 years of age; much younger than the 120-year threshold for 'older forest' as defined by governmental environmental goals. As almost 80% of the production stands ≥10 years old included at least one of the four indicator species, this raises questions regarding the suitability of these species as indictors of forests of high conservational value in southern Sweden. Notably, besides the four species assessed here, none of the additional indicator taxa identified by the government, were recorded in the 10 reserves. This outcome may reflect the difficulties involved in finding bird indicator species indicative of high natural values in this region. Our results highlight the importance of coupling bird surveys with quantified assessments of proximate vegetation cover.

Species co-occurrence and management intensity modulate habitat preferences of forest birds

“…This is partly in accordance with our results in HA landscapes and LMI plots for Eurasian treecreeper, chiffchaff, and long-tailed tit. This showcases a great difficulty in optimizing conservation interventions for the widest possible array of species in forest management strategies targeting the conservation of forest bird species [ 82 ]. This is especially true for cavity nesters, the guild dominated by resident species with many of them being in jeopardy in managed forests in Europe [ 83 – 85 ].…”

The Effect of Forest Management on the Avifauna of a Brazilian Dry Forest

“…Monitoring biodiversity under the impact of human activities is one of the most traditional strategies for wildlife conservation (Magnusson et al, 2018). However, due to the impossibility of monitoring all species, certain groups are considered indicators of environmental quality (Lindbladh et al, 2020). Birds are often used as indicators because they have a well-defined taxonomy, have consistent information about the habitats they occupy, and are relatively easy to survey (Drever et al, 2008;Lindbladh et al, 2020).…”

“…However, due to the impossibility of monitoring all species, certain groups are considered indicators of environmental quality (Lindbladh et al, 2020). Birds are often used as indicators because they have a well-defined taxonomy, have consistent information about the habitats they occupy, and are relatively easy to survey (Drever et al, 2008;Lindbladh et al, 2020). Changes in habitat structure are often reported to affect bird assemblages, however, not all species are affected equally (Shahabuddin and Kumar, 2006).…”

Rebuilding green infrastructure in boreal production forest given future global wood demand

“…Hazel grouse prefers mixed forests with a varied habitat structure and is an indicator species of adequate levels of deciduous trees in boreal landscapes(Åberg et al, 2003). The remaining species are coniferous forest specialists and indicate older forests(Lindbladh et al, 2020); the three-toed woodpecker is considered a good indicator for habitat quality of conifer-dominated forests and a potential umbrella species(Roberge & Angelstam, 2006). Bird species' habitat suitability was projected into the future with logistic regression models developed byHenckel et al (2020), fitted to national data from the Swedish Bird Survey (Appendix S5).The wood-decaying fungi included are five polypores, Amylocystis lapponica, Fomitopsis rosea, Phellinus ferrugineofuscus, Phellinus nigrolimitatus and Phellinus viticola, and one corticioid species, Phlebia centrifuga.…”