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TABLE S1. Three-factor ANOVA analyzing the log(n + 1) transformed number of rock bass (Ambloplites rupestris) and rainbow smelt (Osmerus mordax) observed on night dives in 2016 at the Milwaukee Harbor nature-based breakwater (NBBW) and reference (REF) sites and at two different depths (shallow [2 m] and deep [7 m]).

TABLE  S2. Milwaukee Harbor reference (REF) site stomach contents from a subsample of fish caught during gill netting during 2015 and 2016. Prey items were measured in frequency of occurrence (%F i) in fish without empty stomachs, and numerical proportion (P i) of an item in the diet. Other taxa consumed at the REF included Hydropsychidae, Hydracarinidae, Harpacticoida, Isopoda, and terrestrial insects.

TABLE S3. Milwaukee Harbor nature-based breakwater (NBBW) stomach contents from subsamples of fish caught during gill netting in 2015 and 2016. Prey items are measured in frequency of occurrence (%F i) in fish without empty stomachs, and numerical proportion (P i) of an item in the diet. Other taxa consumed at the GBW included Alewife, Hydropsychidae, Hydracarinidae, Harpacticoida, Isopoda, and diatoms.

FIGURE S1. Alewife (Alosa pseudoharengus) total length (TL) histogram from fish with stomachs sampled in 2016 indicating a year class of age <1 alewife between 70- and 90-mm TL.

FIGURE S2. Temperatures recorded by HOBO pendant temperature loggers at depths of 2 m (black line) and 7 m (gray line) at the northern edge of the green breakwater. Note that in both summer 2015 and 2016 there are wide temperature fluctuations corresponding to coastal upwellings and downwellings.

FIGURE S3. Total (all size and sex categories) Hemimysis anomala per trap by date. Values are the mean ± standard error.

FIGURE S4. Gill net catch of yellow perch (Perca flavescens) during summer 2016.

FIGURE S5. Round goby (Neogobius melanostomus) catch from baited minnow traps set in 2015. Values are the mean ± standard error.