The data consist of latitude and longitude of over 600 nearshore rocky bottom sites that were sampled by SCUBA between 1987 and 2021. The sites are from 38 locations on the north Pacific Rim ranging from Bering Island, along the Aleutian Island chain and the Alaska Peninsula to Southeast Alaska. At each site, counts were made of kelp species and estimates made of the percent cover of fleshy red and other benthic algae, as well as cover by non-motile invertebrates, in twenty 0.25 m quadrats. Urchins were counted and collected from quadrats until either 20 quadrats were sampled or about 200 urchins were collected. Kelp and bottom cover data and the urchin density and size data are presented in other tables. Many of the sites were sampled more than once during the time interval. Sites were plotted at random along the coasts of islands or areas designated. Hard substrate was targeted. Sites included here are at Adak Island, Agattu Island, Akutan Island, Alaid Island, Amchitka Island, Anangula Island, Atka Island, Attu Island, Bering Island, Chiachi Island, Chuginadak Island, Hawadax (formerly Rat) Island, Kiska Island, Kodiak Island, Mitrofania Island, Nizki Island, Ogliuga Island, Sanak Island, Seguam Island, the Semidi Islands, Shemya Island, Sitkalidak Island, Skagul Island, Tanaga Island, Umnak Island, Unalaska Island, Unga Island, Yunaska Island; Amalik Bay, Kukak Bay, and Pavlov Bay on the Alaska Peninsula; Kachemak Bay on the Kenai Peninsula; and Torch Bay, Surge Bay, and Sitka Sound in southeast Alaska. Sea urchin count data, sea urchin size data, and kelp counts and bottom cover data are presented in other tables.