Interspecific Competition between Two Stream Insect Grazers Mediated by Non-Feeding Predatory Fish

Kuhara, Naotoshi; Nakano, Shigeru; Miyasaka, Hitoshi

doi:10.2307/3546993

Cited by 28 publications

(40 citation statements)

References 34 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…We suspect the distribution of Hesperophylax among riffles could indicate that larvae selected leaf packs with a relatively large biomass and where shredder density was low to minimize competition with other shredders. Under this scenario, predatory fish may mediate interspecific competition between shredders, as has been reported for grazing insects (e.g., Kohler and McPeek 1989;Kuhara et al 1999), thereby explaining the absence of Hesperophylax in exclosures. Nevertheless, this hypothesis remains untested.…”

Section: Discussionmentioning

confidence: 90%

“…Heterogeneity can be important within both resource and consumer trophic levels because resources may be unequally vulnerable to consumers and consumers may differ in their preference for and consumption of resources. Examples of heterogeneity in streams include grazers that differ in vulnerability to fish predation (Kohler and McPeek 1989;Kuhara et al 1999) and fish that differ in feeding mode (Dahl and Greenberg 1996b). In our study, heterogeneity within the shredder trophic level may explain the variable, indirect effects of fish on leaf breakdown among riffles.…”

Section: Discussionmentioning

confidence: 92%

See 1 more Smart Citation

Top-down control in a detritus-based food web: fish, shredders, and leaf breakdown

2002

View full text Add to dashboard Cite

We tested the hypothesis that fish decrease shredder abundance in leaf packs, thereby reducing leaf breakdown rates. Our goal was to test for the occurrence of a trophic cascade in a detritus-based food web. Willow leaves (Salix spp.) were fastened into leaf packs and placed into cages (13×13×13 cm) in Valley Creek, Minnesota, USA. Fish were excluded from leaf packs that were placed in cages with mesh on all sides, whereas open control cages allowed fish access to leaf packs. We collected leaf packs from two replicate cages 0, 14, 31, 55, and 112 days after placement in each of three riffles (n=6 per collection). Total abundance of invertebrates and shredders inhabiting leaf packs was significantly higher in exclosures than controls (P<0.01) and increased with exposure time in the stream (P<0.01). Three of the four common shredder taxa had significantly higher biomass in exclosures than controls (P<0.015). Biomass of Hesperophylax (Trichoptera) larvae was significantly higher in controls during the final collections (P<0.03), probably because these large, case-building larvae were less vulnerable to fish predation. Leaf breakdown rates differed significantly between exclosures and controls (P=0.003), but the direction of effects varied among riffles. When shredder density was analyzed separately for each riffle, we found that shredder density may explain differences in leaf breakdown rates between exclosures and controls. The differential responses of shredder taxa to predators may explain variability in fish effects on leaf breakdown. In conclusion, leaf packs did not provide invertebrates refuge from fish predation and fish reduced the densities of most shredders. Fish can indirectly affect leaf breakdown rates, but different responses to predation among taxa within the shredder guild can cause interactions that contradict trophic cascade predictions.

show abstract

Section: Discussionmentioning

confidence: 90%

Section: Discussionmentioning

confidence: 92%

Top-down control in a detritus-based food web: fish, shredders, and leaf breakdown

2002

View full text Add to dashboard Cite

show abstract

“…Because this requires the top predator to have differential effects on the traits of the intraguild predator and prey, this would have to operate via behavior as opposed to morphology for the Ambystoma studied here. Predator-induced behavioral plasticity has been shown to alter interspecific competition in simple food webs (Persson 1991;Werner and Anholt 1996;Kuhara et al 1999). However, the potential behavioral responses of intraguild prey to their intraguild predators as well as the top predators add another layer of complexity to systems with IGP.…”

Section: Top Predators and Coexistence Between Intraguild Predators Amentioning

confidence: 98%

A growth/mortality trade-off in larval salamanders and the coexistence of intraguild predators and prey

Yurewicz

2004

Oecologia

View full text Add to dashboard Cite

Behavioral and morphological traits often influence a key trade-off between resource acquisition and vulnerability to predation, and understanding trait differences between species can provide critical insight into their interactions with other species and their distributions. Such an approach should enhance our understanding of the criteria for coexistence between species that can interact through both competition and predation (i.e. intraguild predators and prey). I conducted a common garden experiment that revealed strong differences between three guild members (larval salamanders Ambystoma laterale, A. maculatum, and A. tigrinum) in behavior, morphology, and growth in the presence and absence of a shared top predator (the larval dragonfly Anax longipes). All three species also reduced their activity and modified their tail fin depth, tail muscle length, and body length in response to non-lethal Anax. Species that act as intraguild predators were more active and could grow faster than their intraguild prey species, but they also suffered higher mortality in laboratory predation trials with Anax. I also used survey data from natural communities to compare the distribution of Ambystoma species between ponds differing in abiotic characteristics and predatory invertebrate assemblages. An intraguild prey species ( A. maculatum) was found more reliably, occurred at higher densities, and was more likely to persist late into the larval period in ponds with more diverse invertebrate predator assemblages. Taken together, these results indicate that top predators such as Anax may play an important role in influencing intraguild interactions among Ambystoma and ultimately their local distribution patterns.

show abstract

“…Models of closed systems suggest that predator-resistant species may benefit from the presence of predators, particularly in more productive habitats Leibold 1996). It has also been shown that open stream systems contain consumers that are "vulnerable" (e.g., mayflies) and "less vulnerable" (consumers with cases or shells) to top predators and that "less vulnerable species" tend not to respond as strongly to predators (Kohler and McPeek 1989;Power 1992;Kuhara et al 1999). Experiments and theoretical models involving drift-feeding fish have shown that changes in the behaviour of mayflies induced by a predator may affect algal biomass, indirectly (e.g., Flecker and Townsend 1994;McIntosh and Townsend 1996;Diehl et al 2000).…”

Section: Introductionmentioning

confidence: 98%

Top-down and bottom-up processes in grassland and forested streams

2003

View full text Add to dashboard Cite

The influence of predatory fish on the structure of stream food webs may be altered by the presence of forest canopy cover, and consequent differences in allochthonous inputs and primary production. Eight sites containing introduced brown trout ( Salmo trutta) and eight sites that did not were sampled in the Cass region, South Island, New Zealand. For each predator category, half the sites were located in southern beech (Nothofagus) forest patches (range of canopy cover, 65-90%) and the other half were in tussock grassland. Food resources used by two dominant herbivores-detritivores were assessed using stable isotopes. (13)C/(12)C ratios were obtained for coarse particulate organic matter (CPOM), fine particulate organic matter (FPOM), algal dominated biofilm from rocks, and larvae of Deleatidium (Ephemeroptera) and Olinga (Trichoptera). Total abundance and biomass of macroinvertebrates did not differ between streams with and without trout, but were significantly higher at grassland sites than forested sites. However, taxon richness and species composition differed substantially between trout and no-trout sites, irrespective of whether streams were located in forest or not. Trout streams typically contained more taxa, had low biomass of predatory invertebrates and large shredders, but a high proportion of consumers with cases or shells. The standing stock of CPOM was higher at forested sites, but there was less FPOM and more algae at sites with trout, regardless of the presence or absence of forest cover. The stable carbon isotope range for biofilm on rocks was broad and encompassed the narrow CPOM and FPOM ranges. At trout sites, carbon isotope ratios of Deleatidium, the most abundant invertebrate primary consumer, were closely related to biofilm values, but no relationship was found at no-trout sites where algal biomass was much lower. These results support a role for both bottom-up and top-down processes in controlling the structure of the stream communities studied, but indicate that predatory fish and forest cover had largely independent effects.

show abstract

Interspecific Competition between Two Stream Insect Grazers Mediated by Non-Feeding Predatory Fish

Cited by 28 publications

References 34 publications

Top-down control in a detritus-based food web: fish, shredders, and leaf breakdown

Top-down control in a detritus-based food web: fish, shredders, and leaf breakdown

A growth/mortality trade-off in larval salamanders and the coexistence of intraguild predators and prey

Top-down and bottom-up processes in grassland and forested streams

Contact Info

Product

Resources

About