Experimental mixtures of dung fauna affect dung decomposition through complex effects of species interactions

Marine reserves are often designed to increase density, biomass, size structure, and biodiversity by prohibiting extractive activities. However, the recovery of predators following the establishment of marine reserves and the consequent cessation of fishing may have indirect negative effects on prey populations by increasing prey mortality. We coupled field surveys with empirical predation assays (i.e. tethering experiments) inside and outside of 3 no-take marine reserves in kelp forests along the central California coast to quantify the strength of interactions between predatory fishes and their crustacean prey. Results indicated elevated densities and biomass of invertebrate predators inside marine reserves compared to nearby fished sites, but no significant differences in prey densities. The increased abundance of predators inside marine reserves translated to a significant increase in mortality of 2 species of decapod crustaceans, the dock shrimp Pandalus danae and the cryptic kelp crab Pugettia richii, in tethering experiments. Shrimp mortality rates were 4.6 times greater, while crab mortality rates were 7 times greater inside reserves. For both prey species, the time to 50% mortality was negatively associated with the density and biomass of invertebrate predators (i.e. higher mortality rates where predators were more abundant). Video analyses indicated that macro-invertivore fishes arrived 2 times faster to tethering arrays at sites inside marine reserves and began attacking tethered prey more rapidly. The results indicate that marine reserves can have direct and indirect effects on predators and their prey, respectively, and highlight the importance of considering species interactions in making management decisions.

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The Ecology of Plant Chemistry and How It Drives Multi-Species Interactions

10.3389/978-2-88963-169-8 ◽

2019 ◽

Keyword(s):

Species Interactions ◽

Plant Chemistry

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Function of coprophagous beetles (Coleoptera: Scarabaeidae, Geotrupidae, Hydrophilidae) in cattle pastures inferred from pitfall trapping data

Journal of Agrobiology ◽

10.2478/s10146-009-0011-2 ◽

2010 ◽

Vol 27 (2) ◽

pp. 85-91 ◽

Cited By ~ 1

Author(s):

Martin Šlachta ◽

Jan Frelich ◽

Tomáš Tonka

Keyword(s):

Seasonal Variation ◽

Spatial Variation ◽

Dry Weight ◽

Seasonal Distribution ◽

The Other ◽

Pitfall Trapping ◽

Other Hand ◽

Nested Anova ◽

Species Groups ◽

Dung Decomposition

Function of coprophagous beetles (Coleoptera: Scarabaeidae, Geotrupidae, Hydrophilidae) in cattle pastures inferred from pitfall trapping dataAn analysis of data on the dry weight biomass of coprophagous beetles in standardized dung (4.5 l) was conducted in order to characterize the spatial and the seasonal distribution of the beetles' biomass in cattle pastures and to elucidate their function in dung decomposition. Nested Anova with factors of farm, site (nested in farm), seasonal period and year was used to evaluate the effect of these factors on the biomass of four functional species groups: the dung dwellers ofScarabaeidae(subfamilyAphodiinae), the dung dwellers ofHydrophilidae, the small tunnellers ofScarabaeidae(subfamilyCoprinae) and the large tunnellers ofGeotrupidae. The spatial variation of biomass (between the sites and the farms) was insignificant (P>0.05) in the two dung-dweller groups and in the large-tunnellers group. On the other hand, a significant (P<0.05) seasonal variation of biomass was found in all but the large tunneller group. In dung dwellers, the spring biomass was formed mainly by two species,Aphodius prodromusandA. sphacelatus. In summer, most of the biomass was accounted for bySphaeridium lunatum, S. scarabaeoidesandA. rufipes. In the two tunneller groups,Onthophagus fracticornis, Geotrupes stercorariusandG. spinigerformed a majority of the biomass in dung.

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Faculty Opinions recommendation of Evolution of species interactions in a biofilm community.

Faculty Opinions – Post-Publication Peer Review of the Biomedical Literature ◽

10.3410/f.1064839.523830 ◽

2007 ◽

Author(s):

Vincent Jansen

Keyword(s):

Species Interactions ◽

Biofilm Community

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Faculty Opinions recommendation of Species interactions in a parasite community drive infection risk in a wildlife population.

Faculty Opinions – Post-Publication Peer Review of the Biomedical Literature ◽

10.3410/f.7412956.7693054 ◽

2010 ◽

Author(s):

Nigel Yoccoz

Keyword(s):

Species Interactions ◽

Parasite Community ◽

Infection Risk ◽

Wildlife Population

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Are local losses of biodiversity causing degraded ecosystem function?

10.1093/oso/9780198808978.003.0004 ◽

2017 ◽

Author(s):

Mark Vellend

Keyword(s):

Ecosystem Function ◽

Species Interactions ◽

Regional Scale ◽

Temporal Trends ◽

Biodiversity Loss ◽

Large Degree ◽

Global Scale ◽

Degraded Ecosystem ◽

Biodiversity Change ◽

Local Extirpation

This chapter highlights the scale dependence of biodiversity change over time and its consequences for arguments about the instrumental value of biodiversity. While biodiversity is in decline on a global scale, the temporal trends on regional and local scales include cases of biodiversity increase, no change, and decline. Environmental change, anthropogenic or otherwise, causes both local extirpation and colonization of species, and thus turnover in species composition, but not necessarily declines in biodiversity. In some situations, such as plants at the regional scale, human-mediated colonizations have greatly outnumbered extinctions, thus causing a marked increase in species richness. Since the potential influence of biodiversity on ecosystem function and services is mediated to a large degree by local or neighborhood species interactions, these results challenge the generality of the argument that biodiversity loss is putting at risk the ecosystem service benefits people receive from nature.

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