Spatial segregation between invasive and native commensal rodents in an urban environment: a case study in Niamey, Niger.
Invasive rodents have been responsible for the diffusion worldwide of many zoonotic agents, thus representing major threats for public health. Cities are important hubs for people and goods exchange and are thus expected to play a pivotal role in invasive commensal rodent dissemination. Yet, data about urban rodents' ecology, especially invasive vs. native species interactions, are dramatically scarce. Here, we provide results of an extensive survey of urban rodents conducted in Niamey, Niger, depicting the early stages of rodent bioinvasions within a city. We explore the species-specific spatial distributions throughout the city using contrasted approaches, namely field sampling, co-occurrence analysis, occupancy modelling and indicator geostatistics. We show that (i) two species (i.e. rural-like vs. truly commensal) assemblages can be identified, and that (ii) within commensal rodents, invasive (Rattus rattus and Mus musculus) and native (Mastomys natalensis) species are spatially segregated. Moreover, several pieces of arguments tend to suggest that these exclusive distributions reflect an ongoing native-to-invasive species turn over. The underlying processes as well as the possible consequences for humans are discussed.
Centre Régional Agrhymet, Département Formation Recherche, Niamey, Niger; Université Abdou Moumouni, Faculté des Sciences, Niamey, Niger; Direction Générale de la Protection des Végétaux, Ministère de l'Agriculture, Niamey, Niger.
Madougou
M
Garba
IRD, Aix Marseille Université, LPED (UMR IRD-AMU), Marseille, France; IRD, CBGP (UMR IRD-INRA-Cirad-SupAgro Montpellier), Campus International de Baillarguet, Montferrier-sur-Lez, France.
Ambroise
A
Dalecky
Centre Régional Agrhymet, USAid/Fews-Net, Niamey, Niger.
Ibrahima
I
Kadaoure
IRD, CBGP, Campus ISRA-IRD de Dakar-Bel-Air, Dakar, Senegal.
Mamadou
M
Kane
Université Abdou Moumouni, Faculté des Sciences, Niamey, Niger.
Karmadine
K
Hima
INRA, CBGP, Campus International de Baillarguet, Montferrier-sur-Lez, France.
Sophie
S
Veran
Centre Régional Agrhymet, Département Formation Recherche, Niamey, Niger.
Sama
S
Gagare
IRD, CBGP (UMR IRD-INRA-Cirad-SupAgro Montpellier), Campus International de Baillarguet, Montferrier-sur-Lez, France.
Philippe
P
Gauthier
INRA, CBGP, Campus International de Baillarguet, Montferrier-sur-Lez, France.
Caroline
C
Tatard
INRA, CBGP, Campus International de Baillarguet, Montferrier-sur-Lez, France.
Jean-Pierre
JP
Rossi
Centre Régional Agrhymet, Département Formation Recherche, Niamey, Niger; IRD, CBGP (UMR IRD-INRA-Cirad-SupAgro Montpellier), Campus International de Baillarguet, Montferrier-sur-Lez, France.
Gauthier
G
Dobigny
D000818:Animals; D044822:Biodiversity; D002947:Cities / Q000706:statistics & numerical data*; D058865:Introduced Species / Q000706:statistics & numerical data*; D009548:Niger; D011634:Public Health; D012375:Rodent Control; D012377:Rodentia; D062206:Spatial Analysis