• Corpus ID: 41962992

Complex trophic interactions in kelp forest ecosystems

@article{Estes2004ComplexTI,
  title={Complex trophic interactions in kelp forest ecosystems},
  author={James A. Estes and Eric M. Danner and Daniel F. Doak and Brenda H. Konar and Alan M. Springer and Peter D. Steinberg and Martin Tim Tinker and Terrie M. Williams},
  journal={Bulletin of Marine Science},
  year={2004},
  volume={74},
  pages={621-638}
}
The distributions and abundances of species and populations change almost continuously. Understanding the processes responsible is perhaps ecologyʼs most fundamental challenge. Kelp-forest ecosystems in southwest Alaska have undergone several phase shifts between alga- and herbivore-dominated states in recent decades. Overhunting and recovery of sea otters caused the earlier shifts. Studies focusing on these changes demonstrate the importance of top-down forcing processes, a variety of indirect… 

Figures and Tables from this paper

Causes and consequences of marine mammal population declines in southwest Alaska: a food-web perspective
Populations of sea otters, seals and sea lions have collapsed across much of southwest Alaska over the past several decades. The sea otter decline set off a trophic cascade in which the coastal
Indirect food web interactions: sea otters and kelp forest fishes in the Aleutian archipelago
TLDR
The overexploitation, recovery and subsequent collapse of sea otter populations in the Aleutian archipelago is used to explore if and how the abundance and diet of kelp forest fishes are influenced by a trophic cascade linking sea otters with sea urchins and fleshy macroalgae.
Serial depletion of marine invertebrates leads to the decline of a strongly interacting grazer.
TLDR
It is proposed that a spatial concentration in shoreline collection pressure through time, increased harvest efficiency, and the serial depletion of alternative marine invertebrate prey have led to intensified per capita predator impacts on Katharina and thus its recent localized decline.
Evaluating trophic cascades as drivers of regime shifts in different ocean ecosystems
In ecosystems that are strongly structured by predation, reducing top predator abundance can alter several lower trophic levels—a process known as a trophic cascade. A persistent trophic cascade also
Patterns of top-down control in a seagrass ecosystem: could a roving apex predator induce a behaviour-mediated trophic cascade?
TLDR
It is suggested that large-bodied grazers likely played important roles in seagrass ecosystem dynamics historically and that roving predators are capable of initiating a behaviour-mediated trophic cascade (BMTC) initiated by tiger sharks and mediated by risk-sensitive foraging by large grazers.
Echinoderms Display Morphological and Behavioural Phenotypic Plasticity in Response to Their Trophic Environment
TLDR
It is shown that sea urchins exhibit significant morphological and behavioural phenotypic plasticity independent of their environment or their nutritional status, which promotes ecological connectivity and weakens species interactions and so increases ecosystem stability.
Individual variability in trophic position and diet of a marine omnivore is linked to kelp bed habitat
TLDR
A novel approach to quantifying the coincidence of landscape- scale nutritional gradients with niche breadth in terms of variability in trophic level and use of basal organic matter sources is demonstrated.
...
...

References

SHOWING 1-10 OF 69 REFERENCES
Limited effects of a keystone species: trends of sea otters and kelp forests at the Semichi Islands, Alaska
TLDR
This study describes a transition state and identifies factors such as keystone species density and residence time that can be important in dictating the degree to which otter effects are manifested.
Evolutionary consequences of food chain length in kelp forest communities.
TLDR
The findings suggest that top-level consumers, acting through food chains of various lengths, can strongly influence the ecology and evolution of plantherbivore interactions.
Kelp forest ecosystems: biodiversity, stability, resilience and future
TLDR
The conditions in which kelp forests develop globally and where, why and at what rate they become deforested are reviewed and overfishing appears to be the greatest manageable threat to kelp forest ecosystems over the 2025 time horizon.
Sequential megafaunal collapse in the North Pacific Ocean: An ongoing legacy of industrial whaling?
  • A. Springer, J. Estes, B. Pfister
  • Environmental Science
    Proceedings of the National Academy of Sciences of the United States of America
  • 2003
TLDR
It is proposed that decimation of the great whales by post-World War II industrial whaling caused the great whale' foremost natural predators, killer whales, to begin feeding more intensively on the smaller marine mammals, thus “fishing-down” this element of the marine food web.
Sea Otters and Kelp Forests in Alaska: Generality and Variation in a Community Ecological Paradigm
TLDR
Analysis of generality of a three-trophic-level cascade among sea otters, invertebrate herbivores, and macroalgae in Alaska demonstrates that sea otter predation has a predictable and broadly generalizable influence on the structure of Alaskan kelp forests.
Inter-decadal patterns of population and dietary change in sea otters at Amchitka Island, Alaska
TLDR
The findings suggest that dietary patterns reflect changes in population status and show how an ecosystem normally under top-down control and limited by coastal zone processes can be significantly perturbed by exogenous events.
Killer whale predation on sea otters linking oceanic and nearshore ecosystems
TLDR
Elevated sea urchin density and the consequent deforestation of kelp beds in the nearshore community demonstrate that the otter's keystone role has been reduced or eliminated in the offshore oceanic ecosystem.
Fishing down marine food webs
TLDR
The mean trophic level of the species groups reported in Food and Agricultural Organization global fisheries statistics declined from 1950 to 1994, and results indicate that present exploitation patterns are unsustainable.
Trophic cascades revealed in diverse ecosystems.
THE EFFECTS OF GRAZING BY SEA URCHINS, STRONGYLOCENTROTUS SPP., ON BENTHIC ALGAL POPULATIONS1
TLDR
Observations of the rate and pattern of algal succession for periods of up to three years showed that following an initial establishment of new species, brown algae began to dominate and the rate of domination is related to the area’s tidal height, with succession most rapid in the lower intertidal areas or subtidally.
...
...