Avian Feeding Preferences of Culex pipiens and Culiseta spp. Along an Urban-to-Wild Gradient in Northern Spain

Abstract

Mosquitoes (Diptera: Culicidae) are regarded as annoying biting pests and vectors of disease-causing agents to humans and other vertebrates worldwide. Factors that affect their distribution and host choice are not well understood. Here, we assessed the species abundance, community composition, and feeding patterns of mosquitoes in an urban-to-wild habitat gradient in northern Spain. Adult mosquitoes from four habitats (urban, periurban, rural, and wild) were collected by aspiration from mid-July to mid-September, 2019. Thirteen species were represented among the 268 specimens (132 females and 136 males) trapped, including six new records reported for the first time in the region. Culex pipiens was the most abundant species in all habitats except in the wild, where Culex territans was dominant. The highest mosquito diversity was recorded in the wild habitat [species richness (S) = 10 and Shannon/Margalef-Diversity Indices (H'/MI = 1.51/1.36)] and the lowest in the urban habitat (S = 3; H'/MI = 0.24/0.41). Blood-engorged specimens (n = 65) represented 49.2% of the total female collections. Eighty percent of the blood-meals (n = 52) were successfully identified based on cytochrome c oxidase I subunit (COI) DNA barcoding. Nine species of birds were identified in blood meals from the three ecological forms of Cx. pipiens (n = 48), Culiseta fumipennis (n = 3), and Culiseta morsitans (n = 1) collected along the four sampling habitats. Four dominant bird species were recorded in Cx. pipiens, i.e., Parus major (35.4%), Turdus merula (18.7%), Pica pica (18.7%), and Passer domesticus (10.4%). Despite the availability of dog and human hosts in the sampling sites located in the urban habitat, Cx. pipiens seemed to have a preference to feed on birds. Culiseta fumipennis blood-meal host records are reported for first time in Europe. These findings on mosquito blood-feeding preferences and habitat community changes will help to better understand vector-host associations and pathogen transmission paths.

Meta-Analysis of the Relative Abundance of Nuisance and Vector Mosquitoes in Urban and Blue-Green Spaces

“…aegypti abundance was significantly higher in traditional urban areas compared to BGSs. Our results are consistent with previous findings that have shown urban BGSs having a variety of effects on mosquito relative abundance [ 12 , 15 , 17 , 18 , 19 , 20 , 21 , 22 ], which may be based on differences in species’ ecologies and the variation present in size and structure of urban BGSs.…”

“…Studies show that important vectors of human disease (e.g., Culex quinquefasciatus , Ae. albopictus ) are present, and often dominant, across land use types (e.g., urban, BGSs) [ 10 , 13 , 15 , 16 ]. The conclusions from these studies support our own, as there was no significant difference in relative abundance between urban and BGSs for Ae.…”

“…VanAcker et al found that the distance between urban BGSs increased both the prevalence of ticks and the risk of Lyme disease [ 9 ]. Mosquito abundance and diversity is generally higher in natural or rural areas than in urban areas [ 10 , 11 , 12 ]; however, vector species are often more prevalent in human-dominated landscapes such as cities [ 13 , 14 ] and are more widespread, being present in a variety of land use types [ 15 , 16 ]. Recent studies have shown inconclusive results when considering urban BGSs and urban space and their effects on relative mosquito abundance.…”

“…Studies focusing on blue-green infrastructure show either a significantly lower [ 17 ] or a similar [ 18 ] abundance of mosquitoes when compared to nearby traditional urban infrastructure. Some studies included in our meta-analysis reported similar relative mosquito abundances between BGSs and their urban counterparts [ 15 , 19 , 20 , 21 ], while others show higher relative abundances in BGSs than in urban spaces [ 12 , 22 ]. Given these varied results, it remains unclear how urban BGS affects relative mosquito abundance.…”

Plasmodium matutinum Transmitted by Culex pipiens as a Cause of Avian Malaria in Captive African Penguins (Spheniscus demersus) in Italy

“…Given the tendency of Cx. pipiens to feed on avian hosts ( 64 ), the water stream, providing habitat for both vectors and birds, may have increased the frequency of reservoir-vector-penguin contacts.…”