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To help determine whether planktonic eggs of fishes on the West Florida Shelf (WFS) are retained locally or exported elsewhere, we collected fish eggs by plankton net from 17 locations (stations) and identified them using DNA barcoding. We then entered the station coordinates into the West Florida Coastal Ocean Model (WFCOM) and simulated the trajectories of the passively drifting eggs over 2 weeks at three depths (surface, midwater, and near bottom). The results indicated there were two groups of trajectories: a nearshore group that tended to be retained and an offshore group that tended toward export and potential long‐distance dispersal. We also found evidence of a relationship between retention and higher fish‐egg abundance; nearshore stations were associated with higher fish‐egg abundances and higher retention. We suggest this is the result of (1) increased spawning in high‐retention areas, (2) increased drift convergence in high‐retention areas, or both processes acting together. Community analysis using SIMPROF indicated the presence of a depth‐related (retention‐related) difference in species assemblages. Fish‐egg species were also categorized as pelagics or non‐pelagics; there was no evidence of pelagic species being more likely to be exported.

Conventional tide gauges are usually housed along the coast. Satellite altimetry works well in the open ocean but poorly near the coast due to signal contamination by land returns. These limitations lead to an observational gap in the transition zone between the coast and open ocean. Using data collected by a GPS installed on top of an anchored spar‐buoy in Tampa Bay, we retrieved water levels through a combination of precise positioning and interferometric reflectometry. Individual water level retrievals agree with a nearby acoustic tide gauge (19.5 km distance) at ∼15 cm level. Amplitude and phase of the major tidal constituents are well recovered by the GPS spar‐buoy measurements. Over a 2.9‐year period, agreement of de‐tided daily mean sea levels measured by the GPS spar‐buoy and the nearby acoustic tide gauge is 4.4 cm. When sea level data measured by the GPS spar‐buoy are included in the local coastal ocean circulation model, low‐frequency error propagated from the open boundary is significantly reduced.

The momentum balance for the density‐driven, nontidal circulation of a partially mixed estuary is generally considered to be between the pressure gradient and vertical friction forces, the result being a two‐layered, mean estuarine circulation often referred to as gravitational convection. All estuaries, however, tend to have geometric complexities that may alter this simplistic view. Here we apply a very high resolution, numerical circulation model to diagnose the momentum balance distributions throughout Tampa Bay, a partially mixed estuary on Florida's west coast. With resolution as fine as 20 m, the model resolves the channels, inlets, bridge causeways, and other geometric complexities that impact the momentum balance distributions. A point‐by‐point, three‐dimensional momentum balance closure analysis demonstrates that while the general expectation for the nontidal estuarine circulation is met, the distribution of terms within the balance is more complex than the simplistic view when real geometries are considered. With Tampa Bay geometries being typical of many partially mixed estuaries, the results herein may also be of a more general nature.