Connectivity of the bay scallop (Argopecten irradians) in Buzzards Bay, Massachusetts, U.S.A.

Abstract

The harvest of bay scallops (Argopecten irradians) from Buzzards Bay, Massachusetts, USA undergoes large interannual fluctuations, varying by more than an order of magnitude in successive years. To investigate the extent to which these fluctuations may be due to yearly variations in the transport of scallop larvae from spawning areas to suitable juvenile habitat (settlement zones), a high-resolution hydrodynamic model was used to drive an individual-based model of scallop larval transport. Model results revealed that scallop spawning in Buzzards Bay occurs during a time when nearshore bay currents were principally directed up-bay in response to a persistent southwesterly sea breeze. This nearshore flow results in substantial transport of larvae from lower-bay spawning areas to settlement zones further up-bay. Averaged over the entire bay, the spawning-to-settlement zone connectivity exhibits little interannual variation. However, connectivities between individual spawning and settlement zones vary by up to an order of magnitude. The model results identified spawning areas that have the greatest probability of transporting larvae to juvenile habitat. Because managers may aim to increase scallop populations either locally or broadly, the high-connectivity spawning areas were divided into: 1) high larval retention and relatively little larval transport to adjoining settlement areas, 2) both significant larval retention and transport to more distant settlement areas, and 3) little larval retention but significant transport to distant settlement areas.

Wind‐Modulated Western Maine Coastal Current and Its Connectivity With the Eastern Maine Coastal Current

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“…In these analyses, online particle tracking modules native to the circulation models are seldom utilized because of the computational expense. Instead, transport of materials is often simulated using offline particle tracking models driven by circulation model output (Liu et al., 2015; S. Wang et al., 2020). The circulation models can be quantitatively evaluated by comparisons between model output and in situ observations, whereas the particle tracking models can be evaluated by comparisons between observed drifter tracks and simulated trajectories of passive particles released at the same times and locations (Bouzaiene et al., 2021; Hart‐Davis et al., 2018; Kako et al., 2010; Thorpe et al., 2004).…”

Numerical Experiments on Variation of Freshwater Plume and Leakage Effect From Mississippi River Diversion in the Lake Pontchartrain Estuary

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Northern quahog (Mercenaria mercenaria) larval transport and settlement modeled for a temperate estuary

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