Assessing connectivity in a fragmented landscape by monitoring the long-distance movements of mountain Galliformes in the French Alps

• Main Authors: Bernard‐laurent, Ariane, Montadert, Marc, Perrot, Charlotte
• Other Authors: Office français de la biodiversité (OFB), Service anthropisation et fonctionnement des écosystèmes terrestres (OFB SAFET), Direction de la recherche et de l’appui scientifique (OFB - DRAS), Office français de la biodiversité (OFB)-Office français de la biodiversité (OFB), Financement OFB, European Project:
• Format: Conference Object
• Language: English
• Published: HAL CCSD 2023
• Subjects: Connectivity; Movements; GPS; moutain galliforms; French Alps; [SDV.BID]Life Sciences [q-bio]/Biodiversity; [SDV.EE]Life Sciences [q-bio]/Ecology; environment; Lagopus muta; rock ptarmigan
• Online Access: https://ofb.hal.science/hal-04361894

International audience Population fragmentation reduces the fitness of the population by increasing the risks of extinction of the different subpopulations that compose it. Fragmentation can be the cause of human actions or natural forces, such the relief in mountain areas which are inherently fragmented environments. Since a few decades, montane Galliformes populations face increasing challenges because of habitat loss and degradation, increasing recreational activities and climate change. Studying long movements is important to evaluate the flow of individuals connecting more or less distant subpopulations and how birds redistribute within landscape units. Here we investigated long-distance movements patterns from marked individuals with GPS transmitters of three galliform species of conservation concern, the Black grouse Lyrurus tetrix, the Rock ptarmigan Lagopus muta and the Rock partridge Alectoris graeca. We analyzed data on movements from 258 adults or subadults monitored during at least 2 successive seasons during the period 2016-2022, from 10 study areas in the French Alps. Of these 258 birds, we focused only on those having performed long-distance movements in order to analyze the role of relief on the chosen paths. We classified these movements in 4 types: end of postnatal dispersal, seasonal migration, erratic/exploratory movement, disturbance-induced flight. Analysis of patterns (frequency, phenology, length of the largest direct flights, elevation distance ratio, ways of overcoming natural barriers) highlighted different flying skills among the three species. These results provide new information to model the link between landscape structure and actual demographic connectivity of populations which can help in conservation management at the appropriate scale.