title: A viable population of the European red squirrel in an urban park.
abstract: Whether urban parks can maintain viable and self-sustaining populations over the long term is questionable. In highly urbanized landscapes, urban parks could play a role in biodiversity conservation by providing habitat and resources to native species. However, populations inhabiting urban parks are usually small and isolated, leading to increased demographic stochasticity and genetic drift, with expected negative consequences on their viability. Here, we investigated a European red squirrel population located in an urban park close to Paris, France (Parc de Sceaux; 184 ha) to assess its viability. Using mitochondrial D-loop sequences and 13 microsatellite loci, we showed that the population presented high levels of genetic variation and no evidence of inbreeding. The size of the population was estimated at 100-120 individuals based on the comparison of two census techniques, Distance Sampling and Capture-Mark-Recapture. The estimated heterozygosity level and population size were integrated in a Population Viability Analysis to project the likelihood of the population's persistence over time. Results indicate that the red squirrel population of this urban park can be viable on the long term (i.e. 20 years) for a range of realistic demographic parameters (juvenile survival at least >40%) and immigration rates (at least one immigration event every two years). This study highlights that urban parks can be potential suitable refuges for the red squirrel, a locally threatened species across western European countries, provided that ecological corridors are maintained.
authors.affiliation: Centre d'Ecologie et des Sciences de la Conservation, Muséum National d'Histoire Naturelle, Paris, France.
authors.forename: Célia
authors.initials: C
authors.lastname: Rézouki
authors.affiliation: Centre d'Ecologie et des Sciences de la Conservation, Muséum National d'Histoire Naturelle, Paris, France.
authors.forename: Anne
authors.initials: A
authors.lastname: Dozières
authors.affiliation: Centre d'Ecologie et des Sciences de la Conservation, Muséum National d'Histoire Naturelle, Paris, France.
authors.forename: Christie
authors.initials: C
authors.lastname: Le Cœur
authors.affiliation: Laboratoire Ecologie Systématique et Evolution, Université Paris-Sud, Orsay, France.
authors.forename: Sophie
authors.initials: S
authors.lastname: Thibault
authors.affiliation: Centre d'Ecologie et des Sciences de la Conservation, Muséum National d'Histoire Naturelle, Paris, France.
authors.forename: Benoît
authors.initials: B
authors.lastname: Pisanu
authors.affiliation: Centre d'Ecologie et des Sciences de la Conservation, Muséum National d'Histoire Naturelle, Paris, France.
authors.forename: Jean-Louis
authors.initials: JL
authors.lastname: Chapuis
authors.affiliation: Laboratoire Ecologie Systématique et Evolution, Université Paris-Sud, Orsay, France.
authors.forename: Emmanuelle
authors.initials: E
authors.lastname: Baudry
mesh_terms: D000818:Animals; D002947:Cities; D056727:Endangered Species; D014644:Genetic Variation; D007178:Inbreeding; D010297:Paris; D000068316:Parks, Recreational; D011156:Population Density; D012589:Sciuridae / Q000235:genetics*; D017422:Sequence Analysis, DNA