Dataset: Vegetative density data from two surveys of eelgrass flowering in shallow and deep zones at four different sites in Massachusetts, USA in 2019

We conducted two surveys of four different eelgrass beds in Massachusetts during the summer of 2019. The four sites were West Beach in Beverly (N 42.55921, W 70.80578), Curlew Beach in Nahant (N 42.42009, W 70.91553), Lynch Park in Beverly (N 42.54488, W 70.85842), and Niles Beach in Gloucester (N 42.59711, W 70.65592). Surveys were done in both the shallow and deep zone. These zones were defined as being along the respective edges of the eelgrass beds. The exact depths of the zones varied from bed to bed. The first survey of each site was conducted at the end of June/early July. In these surveys, we counted the number of both vegetative and flowering shoots in 5-7 0.0625 m^2 quadrats from each of three previously established permanent quadrats per depth per site. This gave us a total of 15-21 0.0625 m^2 quadrats per depth per site. The second survey of each site was conducted in mid-August. Instead of doing the surveys from within the permanent quadrats, we did so outside of them to avoid overlap. We counted the number of vegetative and flowering shoots within 0.0625 m^2 quadrats every 2 m along a 30 m transect (that would be extended for each quadrat that had no eelgrass). This led to there being 15-18 quadrats per depth per site.