Halfway up the trophic chain: development of parasite communities in the sparid fish Boops boops

Abstract

We examined the patterns of composition and structure of parasite communities in the Mediterranean sparid fish Boops boops along a gradient of fish sizes, using a large sample from a single population. We tested the hypothesis that species forming the core of the bogue parasite fauna (i.e. species which have a wide geographical range and are responsible for recognizable community structure) appear early in the fish ontogeny. The sequential community development observed supported the prediction that core species appear in the fish population earlier than rare and stochastic species. There was also a strong correlation between the order of 'arrival ' of the species and their overall prevalence. Six key species were responsible for recognizable community structure across size/age cohorts ; the addition to this baseline community of key parasite species resulted in a nested structure that is linked to differential species abundance rather than fish size. Information on the life-cycles, distribution and host range of the parasites is used to explain the observed patterns of parasite community structure. We conclude that the small mouth size of B. boops coupled with suction feeding may provide a setting for passive sampling as a mechanism leading to non-random parasite community structure.

Experimental parasite community ecology: intraspecific variation in a large tapeworm affects community assembly

“…Fish families were grouped by cage, so the relatively large effect of cage suggests that spatial variation in exposure and/or genetic susceptibility are more important for shaping parasite communities than the interactions between parasite species within a host. Indeed, several studies have found host age or size, factors that influence exposure rates, to affect parasite community structure (Vidal-Martinez, Kennedy & Aguirre-Macedo 1998;Poulin & Valtonen 2001;Zelmer & Arai 2004;P erez-del Olmo et al 2008;Timi, Luque & Poulin 2010). Our results also suggest that interspecific interactions can be obscured by intraspecific variation.…”

Coastal fish farming does not affect the total parasite communities of wild fish in SW Mediterranean

“…In addition, as the values of epidemiological parameters for this parasite were high, it is possible to conclude that L. excisum is a common inhabitant of this fish species in the studied area. However, it is unlikely that this constitutes an enlargement of the parasites host range as L. excisum (i) has been previously described as a generalist by Pérez-Del Olmo et al (2008), and (ii) has been reported parasitizing the related fish species T.…”

Possible seasonal and diurnal modulation of Gammarus pulex (Crustacea, Amphipoda) drift by microsporidian parasites

“…This can happen if small differences in the exposure to parasites occurring at early stages generate large intraspecific differences, while the parasite community of larger individuals might become more homogeneous through repeated parasite exposure, as commonly observed in other aquatic organisms 67 , 68 . However, parasites appearing in early stages might become dominant over time, leading to the homogenization of parasite communities in larger individuals 69 . Homogenization of parasite communities in larger G. pulex individuals might also be favored by cannibalism and size-selective predation, the latter of which might be connected with the removal of large infected individuals (e.g., by predatory fish) and/or small infected individuals (e.g., by predatory macroinvertebrates such as dragonfly larvae) or by a combination of both 70 , 71 .…”