Fig. 1.

Snails compared in this study and map of study area. (A) Larval (Top) and adult (Bottom) eastern mudsnails (T. obsoleta) from tidal inlets and estuaries. (B) Larval (Top) and adult (Bottom) threeline mudsnails (T. trivittata) from the continental shelf. (Scale bars: $\sim 100\mathrm{\mu }$m.) Adult snails are 1–2 cm long. When larvae are oriented passively, ciliated velum is directed upward (out of the page in these photos) and shell downward. (C) Egg capsules were collected on the landward side of Sandy Hook, NJ (T. obsoleta, red down-triangles) and on the continental shelf (T. trivittata, red up-triangles). Wind and wave data were taken from a wave buoy deployed in Delaware Bay (blue square) near T. obsoleta populations and from National Data Buoy Center (NDBC) buoys (blue circles) on the New Jersey shelf near T. trivittata populations. Model results were taken from Delaware Bay (yellow shading) and continental shelf (green shading) sections of a larger Regional Ocean Modeling System (ROMS) model grid (cyan shading).