title: Model-assisted measurements of suspension-feeding flow velocities.
abstract: Benthic marine suspension feeders provide an important link between benthic and pelagic ecosystems. The strength of this link is determined by suspension-feeding rates. Many studies have measured suspension-feeding rates using indirect clearance-rate methods, which are based on the depletion of suspended particles. Direct methods that measure the flow of water itself are less common, but they can be more broadly applied because, unlike indirect methods, direct methods are not affected by properties of the cleared particles. We present pumping rates for three species of suspension feeders, the clamsMya arenariaandMercenaria mercenariaand the tunicateCiona intestinalis, measured using a direct method based on particle image velocimetry (PIV). Past uses of PIV in suspension-feeding studies have been limited by strong laser reflections that interfere with velocity measurements proximate to the siphon. We used a new approach based on fitting PIV-based velocity profile measurements to theoretical profiles from computational fluid dynamic (CFD) models, which allowed us to calculate inhalant siphon Reynolds numbers (Re). We used these inhalantReand measurements of siphon diameters to calculate exhalantRe, pumping rates, and mean inlet and outlet velocities. For the three species studied, inhalantReranged from 8 to 520, and exhalantReranged from 15 to 1073. Volumetric pumping rates ranged from 1.7 to 7.4 l h-1forM. arenaria, 0.3 to 3.6 l h-1forM. mercenariaand 0.07 to 0.97 l h-1forC. intestinalisWe also used CFD models based on measured pumping rates to calculate capture regions, which reveal the spatial extent of pumped water. Combining PIV data with CFD models may be a valuable approach for future suspension-feeding studies.
authors.affiliation: Darling Marine Center, School of Marine Sciences, University of Maine, 193 Clarks Cove Road, Walpole, ME 04573-3307, USA duclos@usf.edu.
authors.forename: Kevin T
authors.identifier: 0000-0002-3017-7777
authors.initials: KT
authors.lastname: Du Clos
authors.affiliation: Darling Marine Center, School of Marine Sciences, University of Maine, 193 Clarks Cove Road, Walpole, ME 04573-3307, USA.
authors.forename: Ian T
authors.initials: IT
authors.lastname: Jones
authors.affiliation: Darling Marine Center, School of Marine Sciences, University of Maine, 193 Clarks Cove Road, Walpole, ME 04573-3307, USA.
authors.forename: Tyler J
authors.initials: TJ
authors.lastname: Carrier
authors.affiliation: Darling Marine Center, School of Marine Sciences, University of Maine, 193 Clarks Cove Road, Walpole, ME 04573-3307, USA.
authors.forename: Damian C
authors.initials: DC
authors.lastname: Brady
authors.affiliation: Darling Marine Center, School of Marine Sciences, University of Maine, 193 Clarks Cove Road, Walpole, ME 04573-3307, USA.
authors.forename: Peter A
authors.initials: PA
authors.lastname: Jumars
mesh_terms: D000818:Animals; D059001:Aquatic Organisms; D049872:Bivalvia / Q000502:physiology*; D003198:Computer Simulation; D005247:Feeding Behavior; D057446:Hydrodynamics; D012212:Rheology / Q000379:methods*; D014561:Urochordata / Q000502:physiology*
keywords: Bivalve; CFD; Fluid mechanics; PIV; Suspension feeding; Tunicate