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Vorticella convallaria are microscopic sessile suspension feeders that live attached to substrates in aquatic environments. They feed using a self‐generated current and help maintain the health of aquatic ecosystems and wastewater treatment facilities by consuming bacteria and detritus. Their environmental impact is mediated by their feeding rate. In ambient flow, feeding rates are highly dependent on an individual's orientation relative to the substrate and the flow. Here, we investigate how this orientation is impacted by flow speed. Furthermore, we examined whether individuals actively avoid orientations unfavorable for feeding. We exposed individuals to unidirectional laminar flow at shear rates of 0, 0.5, 1.0, and 1.5 s−1, and recorded their 3D orientation using a custom biplanar microscope. We determined that V. convallaria orientation became progressively tilted downstream as the shear rate increased, but individuals were still able to actively reorient. Additionally, at higher shear rates, individuals spent a larger fraction of their time in orientations with reduced feeding rates. Our shear rates correspond to freestream flows on the scale of mm s−1 to cm s−1 in natural environments.
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The effect of external flow on 3D orientation of a microscopic sessile suspension feeder, Vorticella convallaria
Abstract Vorticella convallariaare microscopic sessile suspension feeders that live attached to substrates in aquatic environments. They feed using a self‐generated current and help maintain the health of aquatic ecosystems and wastewater treatment facilities by consuming bacteria and detritus. Their environmental impact is mediated by their feeding rate. In ambient flow, feeding rates are highly dependent on an individual's orientation relative to the substrate and the flow. Here, we investigate how this orientation is impacted by flow speed. Furthermore, we examined whether individuals actively avoid orientations unfavorable for feeding. We exposed individuals to unidirectional laminar flow at shear rates of 0, 0.5, 1.0, and 1.5 s−1, and recorded their 3D orientation using a custom biplanar microscope. We determined thatV. convallariaorientation became progressively tilted downstream as the shear rate increased, but individuals were still able to actively reorient. Additionally, at higher shear rates, individuals spent a larger fraction of their time in orientations with reduced feeding rates. Our shear rates correspond to freestream flows on the scale of mm s−1to cm s−1in natural environments.
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- Award ID(s):
- 1755326
- PAR ID:
- 10565252
- Publisher / Repository:
- Wiley
- Date Published:
- Journal Name:
- Annals of the New York Academy of Sciences
- Volume:
- 1537
- Issue:
- 1
- ISSN:
- 0077-8923
- Page Range / eLocation ID:
- 51 to 63
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1111/nyas.15170
