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The data consist of counts of sea urchins in quadrats from 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, divers counted and collected sea urchins from quadrats placed at random distances mostly along a 20-25-foot depth contour. At a subset of sites, 40-foot depths were targeted. Urchins were counted until either 20 quadrats were sampled or about 200 urchins were collected. Quadrat size is specified in the data table but was 0.25 m2 at almost all sites. At the same sites where urchins were counted,...
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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 m2 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...
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Between 1987 and 2021, over 600 nearshore rocky bottom sites were sampled by scuba at 38 locations on the north Pacific Rim ranging from Bering Island, along the Aleutian Island chain and the Alaska Peninsula to southeast Alaska. Sites were plotted at random from along the coasts of islands or areas designated. Hard substrate was targeted. Most sites were sampled more than once, years or decades apart. Many sites in the western Aleutians were resampled several times as sea otter populations densities changed there. Each site was sampled using 20 quadrats along 20-25-foot depth contour. At a subset of sites, 40-foot depths were sampled. Divers counted kelps but non-motile invertebrates, Desmarestia spp. (acid weed),...
Tags: Alaska Peninsula National Wildlife Refuge,
Aquatic Biology,
Ecology,
Russia,
Southeast Alaska, All tags...
Southwest Alaska,
USGS Science Data Catalog (SDC),
Western Aleutian Islands,
benthic ecosystems,
biota,
geography,
location,
sea urchins and sand dollars, Fewer tags
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The data consist of counts of kelps and estimated percent cover of fleshy red algae, other benthic algal cover, and non-motile invertebrates in quadrats from 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, divers counted kelps and estimated percent cover of other algae and encrusting invertebrates in 20 quadrats along 20-25-foot depth contour. At a subset of sites, 40-foot depths were targeted. Quadrat size is specified in the data table but was 0.25 m2 at almost all sites. At the same sites where kelps...
Categories: Data;
Tags: Aleutian Islands,
Gulf of Alaska,
Marine Nearshore Subtidal,
Russia,
Southeast Alaska, All tags...
Southwest Alaska,
Western Aleutian Islands,
benthic ecosystems,
biota,
brown algae and kelp, Fewer tags
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The data consist of test diameters of sea urchins collected from quadrats from 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, divers counted and collected sea urchins from quadrats placed at random distances mostly along a 20-25-foot depth contour. At a subset of sites, 40-foot depths were targeted. Urchins were counted until either 20 quadrats were sampled or about 200 urchins were collected. Collected urchins were measured on the surface with plastic vernier calipers. Quadrat size is specified in...
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