In Memoriam: Gérard Dupré (1947–2026) — A Life Devoted to the Study of Scorpions

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  Photo Credit: Le Parisien In Memoriam: Gérard Dupré (1947–2026) — A Life Devoted to the Study of Scorpions The passing of Gérard Dupré (1947–2026) is a deeply felt loss for those of us who share an interest in the study of scorpions and other arachnids. Throughout his life, he dedicated himself to documenting and preserving arachnological knowledge, contributing valuable work on scorpion taxonomy, distribution, and bibliography. His careful attention to the literature helped bring clarity and organization to a field whose history spans centuries and many languages. Gérard was also closely associated with the journal Arachnides , which became an important outlet for sharing research, faunistic records, and historical notes within the arachnological community. Through this work, he helped ensure that observations and studies—large and small—were preserved and made accessible to others with similar scientific interests. Beyond his scholarly contributions, Gérard was a humble and gen...

Occupancy changes over the summer of the rare fen raft spider Dolomedes plantarius in a drained fen strongly depend on vegetation structure

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Occupancy changes over the summer of the rare fen raft spider Dolomedes plantarius in a drained fen strongly depend on vegetation structure

Abstract

  1. Fens are among the most diverse ecosystems in Europe. They are also highly threatened, mostly by drainage and climate change. Understanding how drought can affect biodiversity in these ecosystems is thus crucial to recommend effective management actions, in particular for species with limited dispersal capacity.
  2. This study investigated the presence of the threatened spider Dolomedes plantarius using a dynamic occupancy approach during spring to summer, a period of high adult activity.
  3. From May to July 2022, we censused adult presence–absence during six visits of 103 transects located in various fen habitats of the Sacy wetlands in northern France.
  4. Species detection probability was low (mean p = 0.21) and maximal at temperatures from 18 to 19°C.
  5. Initial occupancy probability (mean psi = 0.53) was high, positively influenced by water and Cyperaceae cover and negatively by vegetation height.
  6. As the season progressed, the probability of colonization of new transects was low (gamma = 0.09), whereas the probability of extinction in previously occupied transects was high (epsilon = 0.42). This epsilon decreased with maximum litter thickness and sedge tussock cover: these two factors probably protect individuals from heat and drought.
  7. Thus, while hydrological restoration actions of this threatened ecosystem should focus on maintaining high water levels, we also recommend targeting Cyperaceae species, including areas with low vegetation height and maintaining litter and sedge tussocks by extensive grazing or rotational mowing to mitigate drought effects on Dolomedes plantarius.
Gazaix, A., Rendell, C., Berquer, A., Caron, N., Besnard, A., & Couturier, T. Occupancy changes over the summer of the rare fen raft spider Dolomedes plantarius in a drained fen strongly depend on vegetation structure. Insect Conservation and Diversity. https://doi.org/10.1111/icad.70048