Evaluating the link between predation and pest control services in the mite world. Issue 18 (15th August 2020)

• Record Type: Journal Article
• Authors: Roy, Lise; Taudière, Adrien; Papaïx, Julien; Blatrix, Rumsais; Chiron, Geoffrey; Zriki, Ghais; Bonato, Olivier; Barnagaud, Jean‐Yves
• Is Part Of: Ecology and evolution. Volume 10:Issue 18(2020)
• Page Start: 9968
• Page End: 9980
• Publication Date: 2020-08-15
• Subjects: animal farming -- assemblage dynamics -- biological control -- ecosystem services -- predation -- trophic interactions; Ecology -- Periodicals; Evolution -- Periodicals; 577.05
• DOI: 10.1002/ece3.6655
• Languages: English
• ISSNs: 2045-7758

Abstract

Abstract: Pest regulation by natural enemies has a strong potential to reduce the use of synthetic pesticides in agroecosystems. However, the effective role of predation as an ecosystem service remains largely speculative, especially with minute organisms such as mites. Predatory mites are natural enemies for ectoparasites in livestock farms. We tested for an ecosystem level control of the poultry pest Dermanyssus gallinae by other mites naturally present in manure in poultry farms and investigated differences among farming practices (conventional, free‐range, and organic). We used a multiscale approach involving (a) in vitro behavioral predation experiments, (b) arthropod inventories in henhouses with airborne DNA, and (c) a statistical model of covariations in mite abundances comparing farming practices. Behavioral experiments revealed that three mites are prone to feed on D. gallinae . Accordingly, we observed covariations between the pest and these three taxa only, in airborne DNA at the henhouse level, and in mites sampled from manure. In most situations, covariations in abundances were high in magnitude and their sign was positive. Predation on a pest happens naturally in livestock farms due to predatory mites. However, the complex dynamics of mite trophic network prevents the emergence of a consistent assemblage‐level signal of predation. Based on these results, we suggest perspectives for mite‐based pest control and warn against any possible disruption of ignored services through the application of veterinary drugs or pesticides. Abstract : In vitro tests have been confronted with mite inventories and airborne DNA analyses. Three out of seven taxa of native predatory mites are able to feed on Dermanyssus gallinae . The same three predators are associated with the parasite in poultry houses. We've detected no obvious signals from any pest control service. This may be due to the ubiquity of predators or to prey–predator dynamics.