Browsing by Subject "Deming"

Now showing 1 - 3 of 3
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    Chemical sensing in recognition and avoidance of novel predator
    (2010-04-13) Buerkle, Nathan
    Chemical cues are important for predator recognition and avoidance in aquatic environments, where visual cues are not always substantial. Learning, rather than instinct, is important to assessing threat levels, generally requiring the pairing of a predator with an alarm cue of a conspecific. Detection of a novel scent often results in predator inspection to determine motives of the organism. Exposing fish in Deming Lake to two treatments of novel leech species, a visual cue and chemical/visual cue, the experiment shows that redbelly dace (phoxinus eos) preferentially inspect the chemical/visual treatment over the control.
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    The Effects of Fish Presence and Mixing Patterns on Water Clarity in Lakes: Arco, Deming, and Itasca
    (2010-04-12) Harren, Steven; Kartak, Jacob; Knight, Jonathan; Lehman, Justin
    In the summer of 2009, in Itasca State Park, MN, samples of zooplankton, chlorophyll a concentrations, and Secchi disk readings were studied in three lakes with differing characteristics. Our study sites were Deming Lake (fish, meromictic), Arco Lake (fishless, meromictic), and Lake Itasca (fish, dimictic). Our variables of interest were the presence or absence of fish, and whether the lake was dimictic or meromictic. Our study showed that Arco Lake, a small meromictic fishless lake, had the highest Secchi disk reading. Along with a high level of water clarity there was an abundance of large zooplankton. We contributed this high level of clarity with the absence of fish, and its meromictic stratification. Lake Itasca showed its true dimictic characteristics in our data, showing relatively low fluctuations in temperature and dissolved oxygen levels.
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    Teaching wild redbelly dace novel predator cues
    (2010-04-13) Pogatchnik, Brian; Knutson, Quentin
    Alarm cues in fish have been shown to cause anti-predator responses. Although it has been shown that fish can be taught novel predatory cues in laboratory work, it has yet to be demonstrated in the field. In this study we attempt to teach northern redbelly dace in Deming Lake the alarm cue of the yellow perch, a predatory fish that does not occur in Deming Lake. First, perch-naïve dace were tested for response to perch alarm cue. Then they were exposed to a mixture of perch and dace alarm cue and their response to perch alarm cue was re-evaluated the following day. There were no significant differences in fish response to perch alarm cue from the first to the third day. The study showed that it can be difficult to teach a large population of fish a novel predatory cue.