Original provider: NOAA Southeast Fisheries Science Center (SEFSC) Dataset credits: NOAA Southeast Fisheries Science Center (SEFSC) Abstract: As part of GoMMAPPS, the Southeast Fisheries Science Center conducted aerial surveys of continental shelf waters (up to the 200-m isobath) in the U.S. Gulf of Mexico. The survey was conducted between 18 January and 14 March 2018 aboard a NOAA Twin Otter aircraft at an altitude of 600 feet (183 m) and a speed of 100-110 knots (185-204 kph). Survey tracklines were oriented perpendicular to the shoreline and latitudinally spaced 20 km apart. The survey was designed for analysis using Distance sampling with a two-team (independent observer) approach to correct for perception bias in resulting abundance estimates. The study area extended from the shoreline to the 200-m isobath between Tampa, FL and Port O’Connor, TX, and included fine-scale tracklines over estuarine waters of Mississippi Sound. Purpose: The goal of the survey was to conduct line-transect surveys using the Distance sampling approach to estimate the abundance and spatial distribution of marine mammals and sea turtles in waters over the continental shelf in the U.S. Gulf of Mexico. Supplemental information: Provider's survey code is TOSE18WIN. Perpendicular distance to the animal is not publicly available. The dataset is accompanied by transect (effort) data which is provided as a separate file. Sightings included were detected by the forward team. Environmental Attribute Codes Beaufort Sea state 0 Calm, mirror like seas 1 Waves <1ft, rippled surface 2 Small wavelets (<2 ft), no white caps 3 Large wavelets (<3ft), scattered white caps 4 Swell 3-4 ft, numerous white caps 5 Swell >5 ft, many white caps, some spray 6 Swell >10 ft, white caps everywhere, spray CloudCover 0 Clear 1 0-25% Cloudy 2 26-50% Cloudy 3 51-75% Cloudy 4 76-100% Cloudy 5 Overcast Glare (Glare intensity) 0 No Impairment 1 Slight Impairment 2 Moderate Impairment 3 Severe Impairment Weather 0 Clear 1 Mist 2 Light Rain 3 Heavy Rain Conditions 0 Poor 1 Fair 2 Moderate 3 Good 4 Excellent Haze 0 No 1 Yes Fog 0 No 1 Yes Sun penetration (Sun pen) 0 Poor 1 Fair 2 Good 3 Excellent Turbidity 0 Poor 1 Fair 2 Good 3 Excellent