Large-scale habitat model reveals a key role of large trees and protected areas in the metapopulation survival of the saproxylic specialist Cucujus cinnaberinus

Abstract

Deforestation for agricultural purposes and logging over centuries has resulted in a significant loss of forest cover and the deep structural and functional simplification of persistent European woodlands, which has led to a large-scale decline in biodiversity. Despite recent reforestation efforts in many regions of Europe, populations of numerous forest species remain unrecovered. Due to the loss of ecological continuity and the simplification of the ecosystem structure and functionality, the value of secondary forests in sustaining habitat specialists is being questioned. Here, we build a large-scale habitat suitability model to predict the current potential of forests to host populations of the flagship European saproxylic beetle Cucujus cinnaberinus. Our maximum entropy model revealed that the distribution of suitable habitats strongly corresponds to the occurrence of large and well-preserved forest complexes that are characterized by an ecological continuity of the stands. Among the analysed environmental variables, the mean tree diameter and distance to protected areas were the most important suitable habitat contributors. The optimum habitats were identified almost exclusively within some parts of the Carpathians and the northeastern part of the country, particularly in the Białowieża Forest, which include the best preserved European forests. Although a large number of small habitat patches was revealed across the country, these patches were highly scattered and had low predicted suitability. This study demonstrates that most woodlands are unsuitable for C. cinnaberinus, which points to the limited value of secondary forests for habitat specialists. Our findings emphasize the importance of large and intact forests with undisrupted ecological continuity as key areas for the persistence of the rare saproxylic beetle, which provokes questions about the effectiveness of reforestation as a tool for the conservation of forest habitat specialists. Communicated by Nigel E. Stork.

Beetle biodiversity in forest habitats in Laos depends on the level of human exploitation

“…Edwards et al 2011), also the more disturbed forest harboured a considerable number of coleopteran species. In the present study the focus was put on diversity rather than individual species, but it may be hypothesized that secondary forests, such as the more disturbed forest studied here, may have limited value for habitat specialists as has recently been demonstrated for a flagship European saproxylic beetle (Bełcik et al 2019). In general, the still considerable diversity is suggesting that the rate of deforestation of such exploited forests, which is even going on at higher speed compared to that of natural forests (Wilcove et al 2013), should also be of concern.…”

Landscape‐scale dynamics of a threatened species respond to local‐scale conservation management

“…The demographic or physical factors that drive local population dynamics and extinction risk mean that some species, such as amphibians at risk from chytrid fungus (Heard et al 2018), species with very low dispersal ability (for example, saproxylic beetles, small mammals) (Bełcik et al 2019, Smith 2020) or terrestrial mammals at high risk from human–wildlife conflicts and requiring expansive migratory routes (Harris et al 2009, Peters et al 2015), may benefit more from habitat creation, assisted colonization or increasing physical connectivity than managing existing patches. However, in cases where the structure or composition of vegetation appears to determine population density, in situ management can help overcome constraints associated with the area and spatial configuration of patches that might otherwise require more complex habitat creation or schemes working across different landholdings to create physical linkages.…”

From Phenology and Habitat Preferences to Climate Change: Importance of Citizen Science in Studying Insect Ecology in the Continental Scale with American Red Flat Bark Beetle, Cucujus clavipes, as a Model Species

“…In the literature, one can find that all stages of Cucujus clavipes are recorded under the bark of different coniferous and deciduous tree species [ 88 , 94 , 150 , 151 ] but with no details about diameter and length of dead tree. At least some of those factors, which are recognized as very important in other Cucujus species, e.g., [ 152 , 153 , 154 , 155 , 156 , 157 , 158 , 159 , 160 ], possibly can be crucial also in case of C. clavipes .…”