Cetacean and sea turtle visual observations using line-transect survey methods aboard a NOAA DeHavilland DHC-6 Twin Otter (TO) aircraft in the Gulf of Mexico, during the Gulf of Mexico Marine Assessment Program for Protected Species (GoMMAPPS survey TO18Wi) from 2018-01-18 to 2018-03-14 (NCEI Accession 0242273)

As part of the Gulf of Mexico Marine Assessment Program for Protected Species (GoMMAPPS), the Southeast Fisheries Science Center (SEFSC) conducted aerial surveys of the U.S. continental shelf waters (up to the 200-m isobath) in the Gulf of Mexico from 2018-01-18 to 2018-03-14. The survey was designed for a two-team independent visual observer approach with distance sampling to estimate abundance and characterize spatial distribution of marine mammals and sea turtles. This dataset includes marine mammal and sea turtle 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 marine mammal photographs used to aid in species identification

The primary goal was to collect data on the distribution and abundance of marine mammals and sea turtles in the U.S. continental shelf waters of the Gulf of Mexico (GOM) using two independent visual survey teams.

Additional staff support was provided by the NOAA Fisheries Service, Southeast Fisheries Science Center and NOAA Aircraft Operations Center. We would also like to thank the airplane's crew and observers that were involved in collecting these data

Cite as: Litz, Jenny; Rappucci, Gina; Aichinger Dias, Laura; Barry, Kevin; Garrison, Lance; Mullin, Keith (2021). Cetacean and sea turtle visual observations using line-transect survey methods aboard a NOAA DeHavilland DHC-6 Twin Otter (TO) aircraft in the Gulf of Mexico, during the Gulf of Mexico Marine Assessment Program for Protected Species (GoMMAPPS survey TO18Wi) from 2018-01-18 to 2018-03-14 (NCEI Accession 0242273). [indicate subset used]. NOAA National Centers for Environmental Information. https://www.ncei.noaa.gov/archive/accession/0242273. Accessed [date].

This study was funded by the U.S. Department of the Interior, Bureau of Ocean Energy Management through Interagency Agreement M17PG00013 with the U.S. Department of Commerce, National Oceanic and Atmospheric Administration (NOAA).

This research was carried out [in part] under the auspices of the Cooperative Institute for Marine and Atmospheric Studies (CIMAS), a Cooperative Institute of the University of Miami and the National Oceanic and Atmospheric Administration, cooperative agreements NA15OAR4320064 and NA20OAR4320472.

Marine mammal data and photographs were collected under the National Marine Fisheries Service (NMFS), the Marine Mammal Protection Act (MMPA) and Endangered Species Act (ESA) Permit Number: NMFS ESA/MMPA Permit Number 14450

Use liability: NOAA and NCEI cannot provide any warranty as to the accuracy, reliability, or completeness of furnished data. Users assume responsibility to determine the usability of these data. The user is responsible for the results of any application of this data for other than its intended purpose.

Distribution liability: NOAA and NCEI make no warranty, expressed or implied, regarding these data, nor does the fact of distribution constitute such a warranty. NOAA and NCEI cannot assume liability for any damages caused by any errors or omissions in these data. If appropriate, NCEI can only certify that the data it distributes are an authentic copy of the records that were accepted for inclusion in the NCEI archives.

All marine mammal data and photographs were collected under the National Marine Fisheries Service (NMFS), the Marine Mammal Protection Act (MMPA) and Endangered Species Act (ESA) permit number: NMFS ESA/MMPA Permit No.14450. If a photo displaying a marine mammal is used, please include the permit number in the captions and acknowledge NOAA Fisheries.

Cite as: Litz, Jenny; Rappucci, Gina; Aichinger Dias, Laura; Barry, Kevin; Garrison, Lance; Mullin, Keith (2021). Cetacean and sea turtle visual observations using line-transect survey methods aboard a NOAA DeHavilland DHC-6 Twin Otter (TO) aircraft in the Gulf of Mexico, during the Gulf of Mexico Marine Assessment Program for Protected Species (GoMMAPPS survey TO18Wi) from 2018-01-18 to 2018-03-14 (NCEI Accession 0242273). [indicate subset used]. NOAA National Centers for Environmental Information. Dataset. https://doi.org/10.25921/5mer-zp93. Accessed [date].

While still on the plane, observers across both teams discuss and agree upon species identification, group size and behavioral observations for mammal sightings.

Data auditing consisted of making corrections based on error log notes from the field, plotting trackline points to identify errors made when recording effort status, and verifying sighting data based on data sheets from the field