Sharing space between native and invasive small mammals : study of commensal communities in Senegal

2023

Article référencé dans le Web of Science WOS:001067042700001

Granjon Laurent, Artige E., Bâ K., Brouat Carine, Dalecky Ambroise, Diagne C., Diallo M., Fossati Odile, Gauthier Philippe, Kane M., Husse L., Niang Y., Piry S., Sarr N., Sow A., Duplantier Jean-Marc

Ecology and Evolution, 2023, 13 (9), p. e10539 [24 p.] ISSN 2045-7758

Urbanization processes are taking place at a very high rate, especially in Africa. At the same time, a number of small mammal species, be they native or invasive, take advantage of human-induced habitat modifications. They represent commensal communities of organisms that cause a number of inconveniences to humans, including potential reservoirs of zoonotic diseases. We studied via live trapping and habitat characterization such commensal small mammal communities in small villages to large cities of Senegal, to try to understand how the species share this particular space. Seven major species were recorded, with exotic invasive house mice (Mus musculus) and black rats (Rattus rattus) dominating in numbers. The shrew Crocidura olivieri appeared as the main and more widespread native species, while native rodent species (Mastomys natalensis, M. erythroleucus, Arvicanthis niloticus and Praomys daltoni) were less abundant and/or more localized. Habitat preferences, compared between species in terms of room types and characteristics, showed differences among house mice, black rats and M. natalensis especially. Niche (habitat component) breadth and overlap were measured. Among invasive species, the house mouse showed a larger niche breadth than the black rat, and overall, all species displayed high overlap values. Co-occurrence patterns were studied at the global and local scales. The latter show cases of aggregation (between the black rat and native species, for instance) and of segregation (as between the house mouse and the black rat in Tambacounda, or between the black rat and M. natalensis in Kedougou). While updating information on commensal small mammal distribution in Senegal, a country submitted to a dynamic process of invasion by the black rat and the house mouse, we bring original information on how species occupy and share the commensal space, and make predictions on the evolution of these communities in a period of ever-accelerating global changes. We present and analyse data on the distribution of commensal small mammals obtained via intensive trapping operation and habitat description in a series of localities in Senegal, with the aim to: (i) describe the community of small mammals living in contact with humans and evaluate the respective share that native and invasive species occupy with this community; (ii) better understand the factors that govern species distribution and co-occurrence of species using a series of analyses using habitat characteristics gathered at the moment of captures, in view of a better understanding of patterns and processes at work in a group of organisms of particular concern regarding their interactions with humans.image

Sciences du monde animal [080]

SENEGAL

Fonds IRD [F B010090270]

fdi:010090270