Fluid Interactions That Enable Stealth Predation by the Upstream-Foraging Hydromedusa Craspedacusta sowerbyi
| Autor: | Kelsey N. Lucas, Eric Klos, Kakani Katija, John H. Costello, Sean P. Colin |
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| Rok vydání: | 2013 |
| Předmět: |
Video recording
Forage (honey bee) Ecology Foraging Video Recording Front (oceanography) Zoology Biology biology.organism_classification Flow field Biomechanical Phenomena Predation Hydromedusa Hydrozoa Predatory behavior Predatory Behavior Hydrodynamics Water Movements Animals General Agricultural and Biological Sciences |
| Zdroj: | The Biological Bulletin. 225:60-70 |
| ISSN: | 1939-8697 0006-3185 |
| DOI: | 10.1086/bblv225n1p60 |
| Popis: | Unlike most medusae that forage with tenta- cles trailing behind their bells, several species forage up- stream of their bells using aborally located tentacles. It has been hypothesized that these medusae forage as stealth predators by placing their tentacles in more quiescent re- gions of flow around their bells. Consequently, they are able to capture highly mobile, sensitive prey. We used digital particle image velocimetry (DPIV) to quantitatively charac- terize the flow field around Craspedacusta sowerbyi ,a freshwater upstream-foraging hydromedusa, to evaluate the mechanics of its stealth predation. We found that fluid velocities were minimal in front and along the sides of the bell where the tentacles are located. As a result, the defor- mation rates in the regions where the tentacles are located were low, below the threshold rates required to elicit an escape response in several species of copepods. Estimates of their encounter volume rates were examined on the basis of flow past the tentacles, and trade-offs associated with ten- tacle characteristics were evaluated. |
| Databáze: | OpenAIRE |
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