Biology subjects

Baastrup-Spohr, L.

Publications and source records attributed to Baastrup-Spohr, L..

2 recordsLinked to original sources

bioRxiv2023

Rapid and continuing regional decline of butterflies in eastern Denmark 1993-2019

O_LIMany butterfly populations respond negatively to land-use intensification in human-dominated landscapes. However, networks of protected sites have been established with the aim to halt species loss. C_LIO_LIWe undertook annual surveys of all populations of 22 uncommon butterfly species in eastern Denmark during the period 2014-2019 and compared to a systematic atlas survey done 1989-1993, in order to assess trends in regional occupancy of species. C_LIO_LIThree out of 22 species went regionally extinct between 1993 and 2015. One species sustained a single population through the study period. Logistic regression for the remaining 18 species showed 10 to be in strong decline from 1993 to 2015, two showed a declining trend and six had stable trends. For all species except one, the declining trend continued 2015-2019. For five species, a sustained strong decline was evident. C_LIO_LIIn 1993, the total count of populations for all 22 butterfly species was 565, which by 2019 had declined to 158 populations (a 72 % loss over 26 years). From 2015 to 2019, the total count of populations further shrank from 200 to 158 (a 21 % decline over just four years). C_LIO_LILegal protection of areas (Natura 2000 and Danish Nature Protection Act [§]3) was, unexpectedly, not associated with lower probability of local extinction for butterfly population. The observed sustained decline across species suggests an overall low efficiency of the network of protected sites, probably due to a combination of misguided management regimes and payment of extinction debts from the past. C_LI

ecology↗

bioRxiv2021

Distance decay 2.0 - a global synthesis of taxonomic and functional turnover in ecological communities.

Understanding the variation in community composition and species abundances, i.e., {beta}-diversity, is at the heart of community ecology. A common approach to examine {beta}-diversity is to evaluate directional turnover in community composition by measuring the decay in the similarity among pairs of communities along spatial or environmental distances. We provide the first global synthesis of taxonomic and functional distance decay along spatial and environmental distance by analysing 149 datasets comprising different types of organisms and environments. We modelled an exponential distance decay for each dataset using generalized linear models and extracted r2 and slope to analyse the strength and the rate of the decay. We studied whether taxonomic or functional similarity has stronger decay across the spatial and environmental distances. We also unveiled the factors driving the rate of decay across the datasets, including latitude, spatial extent, realm, and organismal features. Taxonomic distance decay was stronger along spatial and environmental distances compared with functional distance decay. The rate of taxonomic spatial distance decay was the fastest in the datasets from mid-latitudes while the rate of functional decay increased with latitude. Overall, datasets covering larger spatial extents showed a lower rate of decay along spatial distances but a higher rate of decay along environmental distances. Marine ecosystems had the slowest rate of decay. This synthesis is an important step towards a more holistic understanding of patterns and drivers of taxonomic and functional {beta}-diversity.

ecology↗