This feature layer presents the extent of floating kelp beds (Nereocystis luetkeana and Macrocystis pyrifera) along the Strait of Juan de Fuca and outer coast of Washington State summarized over the 1989-2021 monitoring period and three Aquatic Reserves over the 2010-2021 period.This summary layer, as well as the underlying annual surveys, are also available as a download. Data are derived from photo interpretation of low tide aerial photography in the late summer, the season of maximum extent. Polygons represent bed extent or planimeter, which include the kelp canopy floating on the surface and small gaps between plants (25 meter threshold for delineating discrete beds). The entire data set is comprised of the following components: yearly inventories (feature classes) from 1989 through 2021, excluding 1993 (kelpYYYY), a combined inventory from all years (kelp1989_2021), a spatial index delineating the geographic extent of monitoring sub-areas (map_index) and tabular data describing kelp characteristics for each year that link to the spatial index (summary_kelps_stats). It was necessary to generalize the polygons in kelp1989_2021 in order to produce a dataset that did not exceed the maximum number of vertices allowed for the feature class. Users who wish to use the most precise inventory estimates should use the tabular summary tables which summarize area by map_index. The tabular estimates are more precise because they are based on the source imagery, while the area estimates in the feature classes reflect subsequent processing.