Publications

@article{Power1992,

title = {Variation in the vulnerability of prey to different predators: Community-level consequences},

author = {M. E. Power and J. C. Marks and Michael S. Parker},

url = {https://angelo.berkeley.edu/wp-content/uploads/sites/59/Power_1992_Eco3.pdf},

doi = {10.2307/1941469},

year  = {1992},

date = {1992-12-00},

journal = {Ecology},

volume = {73},

number = {6},

pages = {2218-2223},

abstract = {Midge larvae (Diptera, Chironomidae) that weave filamentous algae into 

 retreats or tufts, are dominant primary consumers in a river food web. In a previous 

 study, densities of tuft-weaving midges increased in the presence of large fish. In the absence of large fish, midges decreased as densities of predatory invertebrates built up, and higher standing crops of algae were maintained. To examine the mechanisms underlying these dynamics, we compared the vulnerability of tuft-weaving midges (naked or in algal tufts) to fish and predatory invertebrates, in field and laboratory experiments. When midges were exposed for 1 h in the river to fish, 15 out of 15 midges in tufts survived, while 15 of 15 naked midges were consumed. Tufts afforded only partial protection to midges exposed to invertebrate predators, however. After 1 h, enhancement of survivorship by tufts was moderately significant for midges exposed to aeshnids, and insignificant for midges exposed to lestids and naucorids. We suggest that the vulnerability of tuft-weaving midges to invertebrate predators, and their relative invulnerability to fish, sets the stage for trophic cascades observed in this system. Fish, by consuming small predators, release midges, which graze down algae. The strong effects of fish as fourth-level consumers would not be predicted from their diets, in which algivorous mayflies dominate (>60% of the insect biomass found in each of the two most common fish species). Nevertheless, fish in this food web act as fourth-level, rather than third-level, consumers because of the differential vulnerability of one guild of primary consumers, which, when released from predation, can suppress plants.},

keywords = {anti-predator defenses, attached algae, chironomidae, Cladophora, fish, food webs, omnivory, predatory invertebrates, river communities, strong interactors, trophic cascades},

pubstate = {published},

tppubtype = {article}

}

@article{Power1990b,

title = {Effects of fish in river food webs},

author = {M. E. Power},

url = {https://angelo.berkeley.edu/wp-content/uploads/sites/59/Power_1990_Science.pdf},

year  = {1990},

date = {1990-04-10},

journal = {Science},

volume = {250},

pages = {411-415},

abstract = {Experimental manipulations offish in a Northern California river during summer base flow reveal that they have large effects on predators, herbivores, and plants in river food webs. California roach and juvenile steelhead consume predatory insects and fishfry, which feed on algivorous chironomid larvae. In the presence offish, filamentous green algae are reduced to low, prostrate webs, infested with chironomids. When the absence of large fish releases smaller predators that suppress chironomids, algal biomass is higher, and tall upright algal turfs become covered with diatoms and cyanobacteria. These manipulations provide evidence that the Hairston, Smith, Slobodkin-Fretwell theory of trophic control, which predicts that plants will be alternately limited by resources or herbivores in food webs with odd and even numbers of trophic levels, has application to river communities.},

keywords = {fish, river food webs},

pubstate = {published},

tppubtype = {article}

}

@article{Power1988,

title = {Biotic and abiotic controls in river and stream communities},

author = {Mary E. Power and R. Jean Stout and Colbert E. Cushing and Peter P. Harper and F. Richard Hauer and William J. Matthews and Peter B. Moyle and Bernhard Statzner and Irene R. Wais De Badgen},

url = {https://angelo.berkeley.edu/wp-content/uploads/sites/59/Power_1988_BenthoSoc.pdf},

doi = {10.2307/1467301},

year  = {1988},

date = {1988-12-00},

journal = {Journal of the North American Benthological Society},

volume = {7},

number = {4},

pages = {456-479},

abstract = {Lotic ecologists share a major goal of explaining the distribution and abundance of biota in the world's rivers and streams, and of predicting how this biota will respond to change in fluvial ecosystems. We discuss five areas of research that would contribute to our pursuit of this goal. For mechanistic understanding of lotic community dynamics, we need more information on: 

1. Physical conditions impinging on lotic biota, measured on temporal and spatial scales relevant to the organisms. 

2. Responses of lotic biota to discharge fluctuations, including the processes that mediate community recovery following resets caused by spates or droughts. 

3. Movements of lotic organisms that mediate gene flow, resource tracking, and multilevel species interactions. 

4. Life history patterns, with special emphasis on ontogenetic bottlenecks that determine the vulnerability of populations confronting environmental perturbation. 

5. Consequences of species interactions for community- and ecosystem-level processes in rivers and streams. 

Without attempting to be comprehensive in our review, we discuss limits and limitations of our knowledge in these areas. We also suggest types of data and technological development that would advance our understanding. While we appreciate the value and need for empirical and comparative information, we advocate search for key mechanisms underlying community interactions as the crucial step toward developing general predictions of responses to environmental change. These mechanisms are likely to be complex, and elucidation of interacting bilateral, or multilateral, biotic and abiotic controls will progress only with the continuing synthesis of community- and ecosystem-level approaches in lotic ecology.},

keywords = {algae, COMMUNITIES, discharge, disturbance., fish, life histories, rivers, streams, zoobenthos},

pubstate = {published},

tppubtype = {article}

}