Context‐dependent Effects of Fishing: Variation in Trophic Cascades Across Environmental Gradients

Shears, Nick T.; Babcock, Russell C.; Salomon, Anne K.

doi:10.1890/07-1776.1

Cited by 108 publications

(126 citation statements)

References 64 publications

(87 reference statements)

Supporting

Mentioning

121

Contrasting

Order By: Relevance

“…5B). As other recent studies have shown, marine reserve responses may be context dependent and spatially variable as a result of differences in physical and environmental factors, reserve size, the degree and time of reserve protection, and the intensity of fishing pressure outside (37,(39)(40)(41).…”

Section: Discussionmentioning

confidence: 93%

Incorporating biogeography into evaluations of the Channel Islands marine reserve network

Hamilton

Caselle

Malone

et al. 2010

Proc. Natl. Acad. Sci. U.S.A.

148

218

View full text Add to dashboard Cite

Networks of marine reserves are increasingly a major component of many ecosystem-based management plans designed to conserve biodiversity, protect the structure and function of ecosystems, and rebuild and sustain fisheries. There is a growing need for scientific guidance in the design of network-wide monitoring programs to evaluate the efficacy of reserves at meeting their conservation and management goals. Here, we present an evaluation of the Channel Islands reserve network, which was established in 2003 off the coast of southern California. This reserve network spans a major environmental and biogeographic gradient, making it a challenge to assess network-wide responses of many species. Using fish community structure data from a long-term, large-scale monitoring program, we first identified persistent geographic patterns of community structure and the scale at which sites should be grouped for analysis. Fish communities differed most among islands with densities of individual species varying from 3- to 250-fold. Habitat structure differed among islands but not based on reserve status. Across the network, we found that, after 5 years, species targeted by fishing had higher densities (1.5×) and biomass (1.8×) inside reserves, whereas nontargeted species showed no significant differences. Examining trophic groups, piscivore and carnivore biomass was significantly greater inside reserves (1.8× and 1.3× more, respectively), whereas the biomass of planktivores and herbivores was similar inside and out. A framework for incorporating biogeographic variation into reserve network assessments is critical as we move from the evaluation of single reserves to networks of reserves.

show abstract

Section: Discussionmentioning

confidence: 93%

Incorporating biogeography into evaluations of the Channel Islands marine reserve network

Hamilton

Caselle

Malone

et al. 2010

Proc. Natl. Acad. Sci. U.S.A.

148

218

View full text Add to dashboard Cite

show abstract

“…At high disturbance, such as a forest fire or human interventions, all species are at risk. After this seminal paper was published, other investigators reported context-dependent responses in a wide variety of marine [13] and freshwater [14,15] ecosystems. Because context dependency complicates our ability to generalize about important ecological processes, it has undoubtedly contributed to many contentious debates in ecology.…”

Section: Context-dependent Responsesmentioning

confidence: 99%

“…Stable isotopes of nitrogen, carbon, and, more recently, sulfur have added considerably to our understanding, because they trace sources of nutrients to consumers (d 13 C and d 34 S) and measure relative trophic position of the biota (d 15 N) [24]. A popular application of stable isotopes in ecotoxicology is using d 15 N to quantify the rates at which contaminants biomagnify, because concentrations of POPs or methyl Hg are significantly and positively related to trophic position [24][25][26].…”

Section: Fate Of Contaminantsmentioning

confidence: 99%

How do aquatic communities respond to contaminants? It depends on the ecological context

Clements

Hickey

Kidd

2012

Enviro Toxic and Chemistry

View full text Add to dashboard Cite

Recognizing patterns in nature and using these observations to generate and test hypotheses are fundamental components of scientific inquiry [1]. The science of ecotoxicology aims to identify patterns that describe population and community responses to contaminants. Our ability to predict these responses is generally greatest for communities that change consistently in response to a specific contaminant or class of contaminants, thereby providing a direct path to extrapolation, hypothesis testing, and scientific inference (see Predicting the Effects of Contaminants). Although evidence suggests that some communities respond similarly to both natural and anthropogenic stressors [2], we know that regional variation in how communities are composed as a result of environmental, historical, biogeographical, or climatic factors complicates our ability to identify general patterns. Several studies have reported that the effects of contaminants on populations and communities vary along environmental In This Issue: ET&C FOCUSFocus articles are part of a regular series intended to sharpen understanding of current and emerging topics of interest to the scientific community.Abstract-Context dependency refers to variation in ecological patterns and processes across environmental or spatiotemporal gradients. Research on context dependency in basic ecology has focused primarily on variation in the relative importance of species interactions (e.g., competition and predation) among communities. In this Focus article, the authors extend this concept to include variation in responses of communities to contaminants and other anthropogenic stressors. Because the structure of communities varies naturally along environmental gradients, their responses to contaminants may also vary. Similar to the way in which aquatic toxicologists assess abiotic factors associated with contaminant bioavailability, observations about context dependency could be used to test hypotheses about ecological mechanisms responsible for differences in sensitivity among communities. Environ. Toxicol.

show abstract

“…However, a study at a nearby location also found low rates of grazing, although densities of sea urchins were markedly higher (5.8 m -2 ; Vanderklift & Wernberg 2008). There is increasing evidence that, although grazing by sea urchins undoubtedly modifies ecosystems at some places, density of sea urchins alone does not lead to high rates of grazing, as many species assume a drift-feeding behaviour (Castilla & Moreno 1982, Harrold & Reed 1985, Day & Branch 2002a, Shears et al 2008.…”

Section: Low Rates Of Grazing By Fish and Sea Urchinsmentioning

confidence: 99%

Intensity of herbivory on kelp by fish and sea urchins differs between inshore and offshore reefs

Vanderklift¹,

Lavery²,

Waddington³

2009

Mar. Ecol. Prog. Ser.

View full text Add to dashboard Cite

Interactions between water motion, primary productivity, and herbivory are complex. Rates of grazing by fish on tropical coral reefs and by sea urchins on temperate rocky reefs are usually high, but can be low in areas of extreme water motion. Some herbivores can switch between mobile (grazing) and sedentary (drift-feeding) behaviours, and this can be influenced by water motion. We compared the relative consumption of the kelp Ecklonia radiata at rocky reefs in western Australia with different wave exposures (inshore versus offshore). No herbivory was recorded offshore, suggesting that wave exposure might inhibit herbivory. We also compared grazing by fish and sea urchins, and grazing versus drift-feeding pathways. Grazing by fish and sea urchins was low, except at one inshore reef where grazing by fish was intense. In contrast, drift-feeding by sea urchins was recorded at all inshore reefs, suggesting that this is a ubiquitous behaviour in the region. We measured productivity of E. radiata to determine if spatial patterns in rates of herbivory matched those of productivity. Productivity of E. radiata was higher on offshore reefs at one location. The observed difference in consumption between inshore and offshore reefs at both locations suggests that consumption is not limited by productivity, but by exposure. Further, the high productivity offshore combined with low rates of herbivory suggest that offshore reefs might be a source of kelp that subsidises other habitats.

show abstract

Context‐dependent Effects of Fishing: Variation in Trophic Cascades Across Environmental Gradients

Cited by 108 publications

References 64 publications

Incorporating biogeography into evaluations of the Channel Islands marine reserve network

Incorporating biogeography into evaluations of the Channel Islands marine reserve network

How do aquatic communities respond to contaminants? It depends on the ecological context

Intensity of herbivory on kelp by fish and sea urchins differs between inshore and offshore reefs

Contact Info

Product

Resources

About