NOAA Ship Gordon Gunter Vessel Line-transect Survey 2021 (GU2103)

Original provider:
NOAA Southeast Fisheries Science Center (NEFSC)

Dataset credits:
NOAA Southeast Fisheries Science Center (SEFSC)

Abstract:
As part of the Atlantic Marine Assessment Program for Protected Species (AMAPPS), the Southeast Fisheries Science Center (SEFSC) conducted a shipboard survey of the U.S. waters of the Western North Atlantic (WNA) from approximately the 200m isobath out to the U.S. Exclusive Economic Zone (EEZ). The survey was conducted between June 12 and September 5, 2021 onboard the NOAA Ship Gordon Gunter, split into three survey legs.

Due to the COVID-19 pandemic, the scientific staff sheltered-in-place (SIP) before the start of the survey and before leg 3. Multiple days were lost due to mechanical problems with the ship and unfavorable weather conditions. The final portion of this survey transited through the Gulf of America (formerly Gulf of Mexico). The survey was designed for a two-team independent visual observer approach with distance sampling to estimate the detection probabilities for marine mammal sightings.

A sighting constituted a single or group of marine mammals (whales and dolphins) seen at the same location and time. This dataset includes marine mammal visual observation data and effort points with surveying conditions that can be used in abundance and density modeling per visual line-transect survey protocols.

This dataset also includes opportunistic marine mammal photographs and non-marine mammal sightings such as sea turtles. Sea bird observers conducted counts of all birds detected within a 300m strip transect from the ship during all legs of the survey (see additional references and data below). The scientific echosounder (EK) recorded data during the nighttime from the end of the survey day until commencement of acoustic effort, the following morning (CIMAS, NOAA Southeast Fisheries Science Center, 2024). Environmental data was collected at predetermined stations using a conductivity, temperature, and depth sensor (CTD) unit (Wanninkhof, Sullivan, and Pierrot, 2021).