Common Loon - Avian Average Annual Abundance

The data represent predicted number of individuals of each listed seabird species per standardized survey segment (15 minute travel time at 10 knots = approx. 2.5 nautical miles (Nm) or 2.9 statute miles.) Therefore, if the average annual abundance number for a species is 0.2-0.3, then this model estimates that, on average, a single animal would be seen for every 3.3 - 5 survey segments conducted at randomly selected times of the year. Note that some species models were not estimated for all seasons due to very low/no abundance in those seasons, so the annual abundance is based only on the actual seasons modeled, assuming 0 abundance in other seasons. Annual average abundance prediction models were constructed in a study modeling at-sea occurrence and abundance of marine birds (to support Mid-Atlantic marine renewable energy planning). The Compendium of Avian Information in the U.S. Atlantic Outer Continental Shelf was used as a basis for this study, as it characterizes the survey effort and bird observations collected from the Atlantic Outer Continental Shelf since 1978. The study was conducted for BOEM by NOAA/NOS/NCCOS in collaboration with the USGS Patuxent Wildlife Research Center under interagency agreement. Within the study twenty-seven different species were modeled with up to four seasonal models for each species. These seasonal models were then averaged into mean relative abundance layers, which were then reclassified by NOAA OCM into a common classification scheme for display purposes in marinecadastre.gov. Please refer to the final report for more information about how these estimates were calculated.