Rapid evolution of increased vulnerability to an insecticide at the expansion front in a poleward‐moving damselfly

Abstract

Many species are too slow to track their poleward‐moving climate niche under global warming. Pesticide exposure may contribute to this by reducing population growth and impairing flight ability. Moreover, edge populations at the moving range front may be more vulnerable to pesticides because of the rapid evolution of traits to enhance their rate of spread that shunt energy away from detoxification and repair. We exposed replicated edge and core populations of the poleward‐moving damselfly Coenagrion scitulum to the pesticide esfenvalerate at low and high densities. Exposure to esfenvalerate had strong negative effects on survival, growth rate, and development time in the larval stage and negatively affected flight‐related adult traits (mass at emergence, flight muscle mass, and fat content) across metamorphosis. Pesticide effects did not differ between edge and core populations, except that at the high concentration the pesticide‐induced mortality was 17% stronger in edge populations. Pesticide exposure may therefore slow down the range expansion by lowering population growth rates, especially because edge populations suffered a higher mortality, and by negatively affecting dispersal ability by impairing flight‐related traits. These results emphasize the need for direct conservation efforts toward leading‐edge populations for facilitating future range shifts under global warming.

Species Diversity Hinders Adaptation to Toxicants

“…Interspecific competition may act differently from intraspecific competition because competing species occupy different ecological niches. Individuals adapted to their environment typically have a broader niche than nonadapted individuals; , therefore, the niche of an adapted phenotype overlaps more strongly with interspecific competitors than the niche of a nonadapted phenotype. Interspecific competition may thus predominantly affect the adapted phenotype by increasing selection between sensitive and tolerant species .…”

Gregarines modulate insect responses to sublethal insecticide residues

“…A low male body mass can negatively affect reproduction, as it may influence mating success (Candolin 2005 ; Murphy and Krupke 2011 ). For females, exposure to pyrethroids in larval stages is known to lead to a reduced fat content in adult damselflies ( Coenagrion scitulum ) (Dinh et al 2016 ), which may result in less energy allocation towards egg production. Whether the fat content of females of P. cochleariae is affected by insecticide exposure of the larvae remains to be tested.…”

Carry-Over Effects Across Metamorphosis of a Pesticide on Female Lifetime Fitness Strongly Depend on Egg Hatching Phenology: A Longitudinal Study under Seminatural Conditions

“…This simulates spring pesticide applications and the associated runoff in nearby surface waters . The nominal esfenvalerate concentration of 0.2 μg/L induces mortality and reduces growth rate in another Coenagrion damselfly . Although this concentration exceeds the predicted environmental concentrations (e.g., 0.06 μg/L for a realistic scenario), it falls within the range of esfenvalerate concentrations detected in natural water bodies, for example, in Denmark (up to 0.66 μg/L, ref ) and the U.S. (up to 0.8 μg/L, refs − ).…”

“…ref ), we integrated an outdoor microcosm part for the larval stage with a large outdoor insectary part for the adult stage. As pesticide, we chose the pyrethroid insecticide esfenvalerate, one of the most widely applied pyrethroids , that can cause carry-over effects in damselflies. , We applied three pulses (with three-day intervals) of esfenvalerate with a concentration of 0.11 μg/L. As study species we chose the damselfly Coenagrion puella which is common in Europe, and known to react to time constraints by accelerating growth and development rates …”