Gracilaria tikvahiae is a highly opportunistic species common in estuaries and bays, especially where nutrient loading leads to either seasonal or year-round eutrophication (Peckol and Rivers 1995a, 1995b). Its morphology is highly variable, with colors ranging from dark green to shades of red and brown; with outer branches that can be either somewhat flattened or cylindrical in shape (Littler and Littler 1989). It can be found in protected, quiescent bays, as well as in high energy coastline habitats. This species grows free or attached to rocks or other substrata, and can reach a height of 30 cm (Littler and Littler 1989). G. tikvahiae grows to depths of approximately 10 m, but is most common at depths less than 1 m.