Role of saprophagous fly biodiversity in ecological processes and urban ecosystem services

CASTELLI, LUCAS E.; GLEISER, RAQUEL M.; BATTAN HORENSTEIN, M

ECOLOGICAL ENTOMOLOGY

WILEY-BLACKWELL PUBLISHING, INC

Año: 2020 vol. 45 p. 718 - 726

0307-6946

Abstract. 1. Direct consumption of organic matter by the saprophagous larvaeprovides the ecosystem with a fundamental service by recycling nutrients and reducingexposure to decomposing matter. The present study aimed to assess the functional roleof saprophagous flies in the mass loss of different types of decomposing organic matter.2. Two types of common urban waste were used to measure the role of flies in reducingorganicmatter: chicken viscera (chicken) and amixture of flour and uncooked eggs (flourand eggs), representing leftover food. Ten traps baited with each substrate, under fieldconditions, allowed fly access (exposed to flies) and three traps from each substrate didnot (unexposed controls); adult flies entering the traps or emerging from the substratesand substrate mass loss were recorded.3. Species from Calliphoridae, Sarcophagidae, Muscidae, and Fanniidae families werecollected mainly in traps baited with chicken, with Phoridae being the most abundantin traps with flour and eggs as bait. A significantly richer (P<0.05) assemblage of flyspecies accessed the traps baited with chicken viscera (21 species) compared with thoseemerging (11 species), whereas similar numbers of species accessed (n = 5) or emerged(n = 1) from traps baited with flour and eggs (average richness accessing 7.97, emerging2.83). Chicken substratemass loss and species richnesswere positively related (r = 0.56,P = 0.001). In traps where richness was larger than 10 species, the substrates werereduced by more than 85% of their initial weight compared with unexposed controls,which lost 30%. Substrate mass loss significantly increased with the abundance of flies(r = 0.73, P<0.0001).4. The results of the present study support the functional role of saprophagousspecies diversity on the decomposition rates of organic matter, reinforcing the negativeconsequences of loss or gain of species in modified landscapes and for ecosystemfunction.