Recent Submissions

  • Nonbreeding-Season Drivers of Population Dynamics in Seasonal Migrants: Conservation Parallels Across Taxa 

    Calvert, Anna M., Sandra J. Walde, and Philip D. Taylor. 2009. "Nonbreeding-Season Drivers of Population Dynamics in Seasonal Migrants: Conservation Parallels Across Taxa." Avian Conservation and Ecology 4(2): 5-5.
    For seasonal migrants, logistical constraints have often limited conservation efforts to improving survival and reproduction during the breeding season only. Yet, mounting empirical evidence suggests that events occurring ...
  • Surviving historical Patagonian landscapes and climate: molecular insights from Galaxias maculatus 

    Zemlak, Tyler S., Evelyn M. Habit, Sandra J. Walde, Cecilia Carrea, et al. 2010. "Surviving historical Patagonian landscapes and climate: molecular insights from Galaxias maculatus." Bmc Evolutionary Biology 10: 67-67.
    Background: The dynamic geological and climatic histories of temperate South America have played important roles in shaping the contemporary distributions and genetic diversity of endemic freshwater species. We use ...
  • Prey Exchange Rates and the Impact of Predators on Prey Populations in Streams 

    Cooper, S. D., S. J. Walde, and B. L. Peckarsky. 1990. "Prey Exchange Rates and the Impact of Predators on Prey Populations in Streams." Ecology (Washington D C) 71(4): 1503-1514.
    We present four lines of evidence that the magnitude of prey exchange (=immigration/emigration) among substrate patches has an overwhelming influence on the perceived effects of predators on prey populations. (1) An extensive ...
  • A Refuge for Red Scale the Role of Size-Selectivity by a Parasitoid Wasp 

    Walde, S. J., R. F. Luck, D. S. Yu, and W. W. Murdoch. 1989. "A Refuge for Red Scale the Role of Size-Selectivity by a Parasitoid Wasp." Ecology (Washington D C) 70(6): 1700-1706.
    The presence of a physical refuge (an area where mortality due to parasitism is very low) has been demonstrated for California red scale, a pest of citrus. Density of red scale is very high, and parasitism by the principal ...
  • How quality of host plant affects a predator-prey interaction in biological control 

    Walde, Sandra J.. 1995. "How quality of host plant affects a predator-prey interaction in biological control." Ecology (Washington D C) 76(4): 1206-1219.
    In cases of successful biological control the pest population is maintained at low densities by a natural enemy, but the mechanisms by which the predator or parasitoid manages to control the pest are often unknown. This ...
  • Estimation of Temporal Variability in Populations 

    STEWARTOATEN, A., WW MURDOCH, and SJ WALDE. 1995. "Estimation of Temporal Variability in Populations." American Naturalist 146(4): 519-535.
    A common measure of the temporal variability of a population is the standard deviation of the logarithms of successive estimated population sizes, In(D-t). This measure overestimates true temporal variability (the standard ...
  • Intraguild interactions and large-scale population patterns 

    Sircom, Julie, and Sandra J. Walde. 2009. "Intraguild interactions and large-scale population patterns." Journal of the North American Benthological Society 28(3): 649-658.
    Competitive interactions, including interference and intraguild predation, occur in many aquatic food webs and influence large-scale patterns of abundance, especially in lentic habitats. In a study of small coastal streams ...
  • Invertebrate predation and lotic prey communities: Evaluation of in situ enclosure/exclosure experiments 

    Walde, S. J., and R. W. Davies. 1984. "Invertebrate predation and lotic prey communities: Evaluation of in situ enclosure/exclosure experiments." Ecology 65(4): 1206-1213.
    The influence of the stonefly Kogotus nonus on prey communities was assessed by varying the predator density within small enclosures in a first-order stream in southwestern Alberta. Experimental containers with natural ...
  • Patch Dynamics of a Phytophagous Mite Population Effect of Number of Subpopulations 

    Walde, S. J.. 1991. "Patch Dynamics of a Phytophagous Mite Population Effect of Number of Subpopulations." Ecology (Washington D C) 72(5): 1591-1598.
    I conducted a field test of the hypothesis that the dynamics of a predator-prey interaction should be affected by the number of interacting subpopulations within an assemblage. I used a "successful" biological control ...
  • A Refuge for Red Scale Under Control by Aphytis - Structural Aspects 

    MURDOCH, WW, RF LUCK, SJ WALDE, JD REEVE, et al. 1989. "A Refuge for Red Scale Under Control by Aphytis - Structural Aspects." Ecology 70(6): 1707-1714.
    No abstract available.
  • Regulation of an Insect Population Under Biological-Control 

    MURDOCH, WW, RF LUCK, SL SWARBRICK, S. WALDE, et al. 1995. "Regulation of an Insect Population Under Biological-Control." Ecology 76(1): 206-217.
    California red scale is suppressed to very low densities by the parasitoid Aphytis melinus. The system also appears stable. We report on an experimental test of the hypothesis that stability is caused by a refuge for scale. ...
  • Refuge dynamics and metapopulation dynamics: An experimental test 

    Murdoch, WW, SL Swarbrick, RF Luck, S. Walde, et al. 1996. "Refuge dynamics and metapopulation dynamics: An experimental test." American Naturalist 147(3): 424-444.
    Red scale, an insect pest of citrus, is under control by the parasitoid Aphytis melinus in many areas, and in our study area the interaction appears dynamically stable. The bark on the interior branches and trunk of trees ...