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Habitat loss is a serious issue threatening biodiversity across the planet, including coastal habitats that support important fish populations. Many coastal areas have been extensively modified by the construction of infrastructure such as ports, seawalls, docks, and armored shorelines. In addition, habitat restoration and enhancement projects often include constructed breakwaters or reefs. Such infrastructure may have incidental or intended habitat values for fish, yet their physical complexity makes quantitatively sampling these habitats with traditional gears challenging. We used a fleet of unbaited underwater video cameras to quantify fish communities across a variety of constructed and natural habitats in Perdido and Pensacola Bays in the central northern Gulf of Mexico. Between 2019 and 2021, we collected almost 350 replicate 10 min point census videos from rock jetty, seawall, commercial, public, and private docks, artificial reef, restored oyster reef, seagrass, and shallow sandy habitats. We extracted standard metrics of Frequency of Occurrence and MaxN, as well as more recently developed MeanCount for each taxon observed. Using a simple method to measure the visibility range at each sampling site, we calculated the area of the field of view to convert MeanCount to density estimates. Our data revealed abundant fish assemblages on constructed habitats, dominated by important fisheries species, including grey snapper Lutjanus griseus and sheepshead Archosargus probatocephalus. Our analyses suggest that density estimates may be obtained for larger fisheries species under suitable conditions. Although video is limited in more turbid estuarine areas, where conditions allow, it offers a tool to quantify fish communities in structurally complex habitats inaccessible to other quantitative gears.

Living shorelines (LS) are a nature‐based restoration technique that aims to stabilize shorelines while enhancing multiple ecosystem services. In particular, LS are frequently promoted as beneficial for enhancing essential coastal habitats for fish and mobile crustaceans (nekton). In this study, we aimed to assess the effects of LS on nekton habitat across eight LS restoration sites in coastal Alabama, U.S.A., by applying widely‐used community metrics. Nekton abundance, species richness, evenness, and diversity tended to be higher in LS and adjacent unrestored control sites than along nearby hardened shorelines. Community metrics showed no clear effect of LS compared to their adjacent controls, with substantial among‐site variation masking any restoration effect. While this may suggest an ecological equivalence between restored and control sites, there are other possible interpretations; that a lack of difference reflects sampling the same populations at nearby control and restored sites, that differences do exist but sampling effort was insufficient to detect them, or that community metrics may be too insensitive for comparing the effects of various restoration approaches on nekton habitat quality. Further exploration of individual‐based metrics such as growth and condition of key species is warranted, as these may be more sensitive for assessing restoration outcomes and guiding future project designs.