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Abstract Spinosad and indoxacarb are two relatively new insecticides mainly used in agriculture to control insect pests. However, at their current application rates, non-target aquatic insect species may also be impacted. In this study, larvae of the non-biting midge Chironomus riparius were exposed in the laboratory to both insecticides and their effects evaluated at the organismal level, using standard ecotoxicological tests, and at the biochemical level, by monitoring specific oxidative stress, neuronal, and energy metabolism biomarkers. Chronic exposure to both insecticides compromised growth and emergence of C. riparius. Short-term exposures revealed alterations at biochemical level that might be related to the toxicological targets of both insecticides. Growth and development time were the most sensitive endpoints at individual level for both pesticides, while at the biochemical level, the electron transport system activity was the most sensitive biomarker for spinosad exposure, suggesting an increase in energy demands associated with the activation of defense mechanisms. Glutathione-S-transferase was the most sensitive biomarker for indoxacarb exposure, underlining the role of this enzyme in the detoxification of indoxacarb. Additionally, changes in lactate dehydrogenase and glutathione peroxidase activities were observed for both insecticides, and evidences of oxidative damage were found for spinosad. This study contributes to the growing knowledge on sublethal effects of novel insecticides on non-target aquatic invertebrates and strengthens the usefulness of biochemical biomarkers to support the interpretation of their potentially deleterious effects on aquatic insects near agricultural fields. Graphical abstract Unlabelled Image Highlights • Responses of C. riparius to spinosad and indoxacarb exposure were investigated. • Exposure to both insecticides compromised C. riparius life-history traits. • Both insecticides induced defense mechanisms and cellular oxygen consumption. • Non-target aquatic insect species may be impacted by spinosad and indoxacarb use. [ABSTRACT FROM AUTHOR]

1. Marine reserves are widely used for conservation and fisheries management. However, there is debate surrounding the speed of population recovery inside reserves and how recovery differs among species. Here, we determine how reserve effectiveness in enhancing fish density changes with reserve age. We also examine how the effects of protection vary between fished and non-fished species and among species of different body sizes, which we use as a proxy for life history and ecology. 2. We meta-analysed over 1000 ratios of fish densities (inside : outside reserves) taken from reserves of 1–26 years old from around the world. 3. Overall, older reserves were more effective than younger reserves, with fish densities increasing within reserves by ∼5% per annum relative to unprotected areas. Reserves older than 15 years consistently harboured more fish compared with unprotected areas; younger reserves were less reliably effective. 4. Large, fished species responded strongly and positively to protection in old (>15 years) and, unexpectedly, in new and young (≤10 years) reserves. Small, fished species and non-fished species of all sizes showed weaker responses to protection that did not vary predictably with reserve age. 5. We expected large fish to respond more slowly to protection than smaller species. We also expected small species to decline after large fish had recovered (i.e. trophic cascades). Neither prediction was supported. 6. Synthesis and applications. Our meta-analyses demonstrate that, globally, old reserves are more effective than young reserves at increasing fish densities. Our results imply that reserves should be maintained for up to 15 years following establishment, even if they initially appear ineffective. If protection is maintained for long enough, fish densities within reserves will recover and such benefits will be particularly pronounced for large, locally fished species. [ABSTRACT FROM AUTHOR]