Dynamics of the macroinvertebrate community and food web of a Mediterranean stream

Abstract

Here, we analyse the annual dynamics in the diversity and the food web structure of the macroinvertebrate community in a Mediterranean permanent stream. Then, we also tested the validity of different proposed predictive models in their ability to fit our results. We calculated the Shannon-Wiener diversity index, the evenness, several food web properties and the proportion of functional feeding groups throughout the year. Our results showed a great variability of the studied parameters with time, mainly in terms of trophic relationships among macroinvertebrates. Diversity did not fluctuate substantially, but functional feeding groups did. In the same manner, complexity of the food web also varied substantially along the year. Comparisons with the considered models showed that, overall, none of the models predicted accurately the observed values. Nevertheless, within them, at least some estimated relatively realistic values, mainly when considering data monthly. From a functional point of view, collector-gatherers were the most abundant group throughout the sampling period except in autumn, when scrapers were also proportionally important. Predators were present during the entire period but with a low abundance. Thus, this study underlines the importance of considering not only static, but also dynamic data when studying food webs.

Macroinvertebrates on the front lines: projected community response to temperature and precipitation changes in Mediterranean streams

“…Some sites were sampled only once, others were sampled during different years (maximum 4). Although some seasonal variation has been observed, sampling any season except winter yields relatively similar communities in this region (Hering et al 2004;Navarro-Ll acer 2006;Vannucchi et al 2017). Multiple samples at a site during different years are treated as independent because they are being related to annual weather metrics.…”

The effect of large predators on the decomposition rate and the macroinvertebrate colonization pattern of leaves in a Mediterranean stream

“…Chironomidae use to dominate the invertebrate fauna in terms of absolute numbers in many freshwater systems (Brittain, ; Ferrington, ; Ferrington, Berg, & Coffman, ) and particularly in streams from the Iberian Peninsula (e.g., López‐Rodríguez, Peralta‐Maraver et al, ; Oscoz, Galicia, & Miranda, ; Vannucchi, Peralta‐Maraver, Tierno de Figueroa, & López‐Rodríguez, ), such as the one we studied. Baetidae uses to be another dominant group in many streams and rivers (see previous references), but in our reach, this group is surpassed by other families, such as Ephemerellidae, Elmidae, and Leuctridae.…”

Spatial and seasonal variability in the trophic role of aquatic insects: An assessment of functional feeding group applicability

“…Bo, Fenoglio, López‐Rodríguez, & Tierno de Figueroa, ; López‐Rodríguez et al., ; Tierno de Figueroa et al., ) and the food web of benthic fauna in Mediterranean streams (e.g. López‐Rodríguez et al., ; Peralta‐Maraver, López‐Rodríguez, & Tierno de Figueroa, ; Vannucchi, López‐Rodríguez, Tierno de Figueroa, & Gaino, ; Vannucchi, Peralta‐Maraver, Tierno de Figueroa, & López‐Rodríguez, ).…”