| File(s) | Type | Description | Action |
|---|---|---|---|
| historical.csv (15.64 MB) | Comma Separated Values (.csv) | Primary data file for dataset ID 753142 | Add to Cart Download |
| Supplemental File(s) | Type | Description | Action |
| species_overlap_BCO.R (5.63 KB) | Octet Stream | <p>This R-file uses R datafiles available from the following dataset landing pages:</p> <p>"Observed and modeled presence 1968-2014": https://www.bco-dmo.org/dataset/753142 </br>* historical.RData </p> <p>"Projected species probability of occupancy and abundance under ocean warming": https://www.bco-dmo.org/dataset/753188 </br>* projected.RData </p> <p>Range size and species overlap</p> <p>For each year, observations and predictions of historical species occupancy were aggregated to 0.5°latitude x 0.5°longitude grid cells by taking the average across hauls in each cell. Data in each year was further trimmed to the 113 grid cells that were observed in at least 30 years. Observed range size for species x in year y was calculated as the proportion of grid cells in the study region in which the species was present to account for differences in the intensity of sampling between years. The observed fraction of prey A’s range occupied by predator B was defined as the number of sites occupied by both species relative to the total number of sites occupied by species A. </p> <p>To calculate a species’ predicted range extent from the species distribution models, we computed the average occupancy probability of that species across all sites in the region. To predict the fraction of prey A’s range occupied by predator B, the cumulative joint probability of both species was divided by the cumulative probability for species A across all sites in the study region.</p> | Add to Cart Download |
©2020 Biological and Chemical Oceanography Data Management Office.Funded by the U.S. National Science Foundation