Modeling Macroinvertebrate Community Dynamics in Stream Mesocosms Contaminated with a Pesticide

Abstract

Modeling community dynamics of aquatic invertebrates is an important but challenging task, in particular in ecotoxicological risk assessment. Systematic parameter estimation and rigorous assessment of model uncertainty are often lacking in such applications. We applied the mechanistic food web model Streambugs to investigate the temporal development of the macroinvertebrate community in an ecotoxicological mesocosm experiment with pulsed contaminations with the insecticide thiacloprid. We used Bayesian inference to estimate parameters and their uncertainty. Approx. 85% of all experimental observations lie within the 90% uncertainty intervals indicating reasonably good fits of the calibrated model. However, a validation with independent data was not possible due to lacking data. Investigation of vital rates and limiting factors in the model yielded insights into recovery dynamics. Inclusion of the emergence process and sub-lethal effects turned out to be potentially relevant model extensions. Measurements of food source dynamics, individual body size (classes), and additional knowledge on sub-lethal effects would support more accurate modeling. This application of a process-based, ecotoxicological community model with uncertainty assessment by Bayesian inference increased our process understanding of toxicant effects in macroinvertebrate communities and helped identifying potential improvements in model structure and experimental design.

Effects of clothianidin on aquatic communities: Evaluating the impacts of lethal and sublethal exposure to neonicotinoids

“…Our data suggest that prey species embedded within communities containing invertebrate predators can benefit from neonicotinoid exposure; these results are not exclusive to neonicotinoids. Ecotoxicology experiments using communities have observed an increase in herbivore survival as a result of predator elimination across a diversity of chemicals including neonicotinoids [21,27,33,48,64–67]. Zooplankton were the only group that were largely unaffected by our treatments.…”

An update of the Worldwide Integrated Assessment (WIA) on systemic insecticides. Part 2: impacts on organisms and ecosystems

“…The main taxa affected have been discussed above and include key species such as midges and other Diptera such as mayflies, stoneflies, and caddisflies as well as predatory dragonflies, damselflies, bugs, and beetles. The most sensitive species are detritivorous that fulfill an essential role in the recycling of organic matter in streams (Kreutzweiser et al 2008a), and low water residue levels induces sublethal effects that impair their ability to perform this role (Kattwinkel et al 2016), while their elimination translates into alterations in ecosystem functions, like leaf litter breakdown (Englert et al 2012). Most of these taxa have aquatic larval stages and produce a large biomass that feeds a diverse array of insectivorous vertebrates such as newts, frogs, lizards, aquatic shrews, and birds.…”

Mechanistic modelling for predicting the effects of restoration, invasion and pollution on benthic macroinvertebrate communities in rivers

“…A detailed model description is provided in Appendix S1 (see also Kattwinkel, Reichert, R€ uegg, Liess, & Schuwirth, 2016;Schuwirth & Reichert, 2013;Schuwirth et al, 2016). A detailed model description is provided in Appendix S1 (see also Kattwinkel, Reichert, R€ uegg, Liess, & Schuwirth, 2016;Schuwirth & Reichert, 2013;Schuwirth et al, 2016).…”