Abstract / Summary
Aedes albopictus and Aedes aegypti are invasive container-breeding mosquitoes whose expanding distributions increasingly overlap with resident mosquito species in human-modified environments. In northeastern Türkiye, urban artificial habitats provide a field system in which invasive Aedes species and the resident Culex pipiens may share larval habitats. This study aimed to reveal the field-level structure of larval habitat sharing, habitat occupancy and co-occurrence patterns between invasive Aedes species and the resident Cx. pipiens in the Eastern Black Sea Region between 2014 and 2019. Larval mosquito surveys were conducted in Artvin, Rize and Trabzon provinces during the mosquito-active season from April to October between 2014 and 2019. Larvae were collected from accessible water-holding habitats, morphologically identified to species level, and analysed using sampling site-year records as the basic analytical unit. Annual larval abundance, habitat occupancy and pairwise co-occurrence patterns were evaluated using abundance data and presence–absence matrices. A total of 33.277 larvae belonging to the three species were recorded. Ae. albopictus was the most abundant species, with 18,301 (55%), followed by Cx. pipiens with 13.492 (40.54%) and Ae. aegypti with 1.484 (4.46%). Annual abundance patterns indicated a marked temporal shift in larval community composition; Cx. pipiens dominated early in the study period, whereas Ae. albopictus became numerically dominant from 2016 onwards. Of the 2.142 sampling site-year records examined, 652 were positive for at least one mosquito species. Most positive records contained only a single mosquito species (589, 90.34%), whereas two-species co-occurrence (60, 9.20%) and three-species co-occurrence (3, 0.46%) were observed at much lower frequencies. The most frequent two-species combination was Ae. aegypti and Ae. albopictus, mainly associated with discarded tires and artificial containers. Ae. albopictus and Cx. pipiens showed limited overlap, while Ae. aegypti and Cx. pipiens showed no significant pairwise association. These findings indicate that larval mosquito communities in northeastern Türkiye have undergone habitat-mediated temporal restructuring associated with the increasing dominance of Ae. albopictus. Overall, the results highlight the importance of discarded vehicle tires and artificial containers as critical larval habitats for invasive Aedes mosquitoes in the region and support the need for habitat-focused larval surveillance in the Eastern Black Sea Region.