Microclimate and larval habitat density predict adult Aedes albopictus abundance in urban areas

Abstract

word count (max 250): 216 17 Text word count: 3753 18 ABSTRACT 30The Asian tiger mosquito, Aedes albopictus, transmits several arboviruses of public 31 health importance, including chikungunya and Zika. Since its introduction to the United States in 32 1985, the species has invaded over forty states, including temperate areas not previously at risk 33 of Aedes-transmitted arboviruses. Mathematical models incorporate climatic variables in 34 predictions of site-specific Ae. albopictus abundances to identify human populations at risk of 35 disease. However, these models rely on coarse resolutions of environmental data that may not 36 accurately represent the climatic profile experienced by mosquitoes in the field, particularly in 37 climatically-heterogeneous urban areas. In this study, we pair field surveys of larval and adult 38Ae. albopictus mosquitoes with site-specific microclimate data across a range of land use types 39 to investigate the relationships between microclimate, density of larval habitat, and adult 40 mosquito abundance and determine whether these relationships change across an urban 41 gradient. We find no evidence for a difference in larval habitat density or adult abundance 42 between rural, suburban, and urban land classes. Adult abundance increases with increasing 43 larval habitat density, which itself is dependent on microclimate. Adult abundance is strongly 44 explained by microclimate variables, demonstrating that theoretically derived, lab-parameterized 45 relationships in ectotherm physiology apply to the field. Our results provide support for the 46 continued use of temperature-dependent models to predict Ae. albopictus abundance in urban 47 areas. 48 49 cooler climates than Ae. aegypti. Following initial establishment in Texas, Ae. albopictus has 56 invaded over 40 states, 7 and models predict its range will expand as the climate warms. 8,9 At 57 present, established populations of Ae. albopictus are found in the United States as far north as 58Connecticut and New York, 10,11 well outside the present range of Ae. aegypti. Ae. albopictus is 59 implicated in transmission cycles of dengue and chikungunya in the Mediterranean region of 60 Europe, 12,13 which suggests that temperate regions of the US may be similarly vulnerable. 61Given the potential role of Ae. albopictus in disease transmission, it is important to 62 understand what factors influence its abundance. Ae. albopictus is sensitive to variation in 63 temperature due to temperature-dependent life history traits such as development rates, 64 fecundity, and survival. [14][15][16] Climate or meteorological predictors are widely used in mechanistic 65 models and statistical models. [17][18][19][20][21][22] Models leverage these relationships to predict mosquito 66 presence, population growth rates, and abundances based on temperature metrics derived from 67 weather stations or remotely-sensed datasets. However, urban landscapes are composed of a 68 variety of land classes (e.g. residential, developed, vegetated), which vary in th...

Landscape and Anthropogenic Factors Associated with Adult Aedes aegypti and Aedes albopictus in Small Cities in the Southern Great Plains

“…albopictus was associated with decreasing levels of urbanization (decreasing percentage of impervious surface, numbers of containers) and increasing levels of vegetation (increasing percentage of tree cover, rural sites). While biases in trap placement may have led to some of these ambiguous results, overall, it aligns with other landscape-focused studies in the United States [ 45 , 46 , 47 , 48 ]. In general, Ae.…”

“…The impact of abiotic and biotic factors on the development of Ae. albopictus in urban zones is well studied [ 42 , 43 , 44 , 45 ] and appears to be similar in the southern Great Plains. One interesting result was the higher abundance of Cx.…”

“…aegypti and Ae. albopictus populations in urban landscapes has mainly been studied in large urban centers in the US [ 21 , 35 , 40 , 41 , 43 , 45 , 46 , 47 , 48 , 53 ]. The unique landscapes of small urban clusters throughout the southern Great Plains where Aedes species thrive provide challenges for conceptualizing regional mosquito management.…”

Land cover affects microclimate and temperature suitability for arbovirus transmission in an urban landscape

“…In most studies to date, the effects of habitat on mosquitoes have been modeled using land cover, land use, and socioeconomic indicators as indirect proxies [ 33 – 35 ]. However, recent studies combining direct monitoring of urban microclimates with field experiments [ 36 ] and observations of mosquito abundance [ 37 ] have found that variation in local temperatures account for some of the differences in mosquito abundance and life history traits across urban, suburban, and rural habitats. These results highlight the prospects for synthesizing our understanding of the thermal biology of mosquitoes with knowledge of the physical dynamics of urban climate to determine when and where microclimate conditions for disease transmission will be highest.…”

Effects of seasonality and land use on the diversity, relative abundance, and distribution of mosquitoes on St. Kitts, West Indies

“…aegypti were significantly lower across non-urban habitats, their presence in other land covers on St. Kitts and other Caribbean islands [ 11 , 37 ] could have several implications for our understanding of the general ecology of this species and transmission of arboviruses in the Caribbean. Mosquitoes living across these land covers likely experience variation in local microclimate [ 69 , 74 ], quality and quantity of oviposition sites [ 11 , 37 ], and access to vertebrate species available for blood-feeding [ 75 ]. This variation in turn could result in potential disease transmission among sylvatic reservoirs (e.g.…”