Large vessel surveys were conducted during the summer of 2009 and the winter of 2010 in the north-central Gulf of Mexico to examine the spatial distribution of sperm whales and to collect data on potential midwater prey. The vessel surveys included both visual and passive acoustic data collection to document the presence of sperm whales. Physical oceanographic data was collected to characterize the presence of eddies and other mesoscale physical features that have the potential to concentrate both sperm whales and their prey. Midwater trawls were deployed to collect specimens of midwater squids to identify likely prey items. These data are used to characterize the midwater prey community that supports sperm whale populations in the Gulf of Mexico.

This record represents killer whale sound production. Killer whale calls were detected by analysts and logged using Triton's Logger Remora. Calls were grouped into encounters, with encounters more than 30 min apart being logged as separate encounters. The following settings were used for manual scanning of long-term spectral averages: bandwidth 0-5000 Hz; 1 hour duration; and for zoomed-in scanning of spectrograms: plot length 30 s, FFT length 1000, 90% overlap. Killer whale encounters were further classified into ecotypes based on the presence of ecotype-specific call types in the encounter. Call types were identified in the spectrogram window, and all calls in an encounter were examined before an encounter was attributed to a particular ecotype. Resident ecotype call types were identified from the reference catalogue of Ford 1987, transient ecotype call types were identified from a reference catalogue based on recordings published by Deecke 2003, and offshore ecotype call types were identified from a digital catalogue (J Ford, unpubl. data) collected during field encounters with photo- or genetically identified offshore killer whales.These data were recorded at SanctSound Site OC02_04 between July 13, 2020 and October 01, 2020.

This record represents killer whale sound production. Killer whale calls were detected by analysts and logged using Triton's Logger Remora. Calls were grouped into encounters, with encounters more than 30 min apart being logged as separate encounters. The following settings were used for manual scanning of long-term spectral averages: bandwidth 0-5000 Hz; 1 hour duration; and for zoomed-in scanning of spectrograms: plot length 30 s, FFT length 1000, 90% overlap. Killer whale encounters were further classified into ecotypes based on the presence of ecotype-specific call types in the encounter. Call types were identified in the spectrogram window, and all calls in an encounter were examined before an encounter was attributed to a particular ecotype. Resident ecotype call types were identified from the reference catalogue of Ford 1987, transient ecotype call types were identified from a reference catalogue based on recordings published by Deecke 2003, and offshore ecotype call types were identified from a digital catalogue (J Ford, unpubl. data) collected during field encounters with photo- or genetically identified offshore killer whales.These data were recorded at SanctSound Site OC01_03 between November 02, 2019 and April 10, 2020.

This record represents killer whale sound production. Killer whale calls were detected by analysts and logged using Triton's Logger Remora. Calls were grouped into encounters, with encounters more than 30 min apart being logged as separate encounters. The following settings were used for manual scanning of long-term spectral averages: bandwidth 0-5000 Hz; 1 hour duration; and for zoomed-in scanning of spectrograms: plot length 30 s, FFT length 1000, 90% overlap. Killer whale encounters were further classified into ecotypes based on the presence of ecotype-specific call types in the encounter. Call types were identified in the spectrogram window, and all calls in an encounter were examined before an encounter was attributed to a particular ecotype. Resident ecotype call types were identified from the reference catalogue of Ford 1987, transient ecotype call types were identified from a reference catalogue based on recordings published by Deecke 2003, and offshore ecotype call types were identified from a digital catalogue (J Ford, unpubl. data) collected during field encounters with photo- or genetically identified offshore killer whales.These data were recorded at SanctSound Site OC02_02 between July 11, 2019 and October 30, 2019.

This record represents killer whale sound production. Killer whale calls were detected by analysts and logged using Triton's Logger Remora. Calls were grouped into encounters, with encounters more than 30 min apart being logged as separate encounters. The following settings were used for manual scanning of long-term spectral averages: bandwidth 0-5000 Hz; 1 hour duration; and for zoomed-in scanning of spectrograms: plot length 30 s, FFT length 1000, 90% overlap. Killer whale encounters were further classified into ecotypes based on the presence of ecotype-specific call types in the encounter. Call types were identified in the spectrogram window, and all calls in an encounter were examined before an encounter was attributed to a particular ecotype. Resident ecotype call types were identified from the reference catalogue of Ford 1987, transient ecotype call types were identified from a reference catalogue based on recordings published by Deecke 2003, and offshore ecotype call types were identified from a digital catalogue (J Ford, unpubl. data) collected during field encounters with photo- or genetically identified offshore killer whales.These data were recorded at SanctSound Site OC02_01 between March 08, 2019 and April 24, 2019.

This record represents killer whale sound production. Killer whale calls were detected by analysts and logged using Triton's Logger Remora. Calls were grouped into encounters, with encounters more than 30 min apart being logged as separate encounters. The following settings were used for manual scanning of long-term spectral averages: bandwidth 0-5000 Hz; 1 hour duration; and for zoomed-in scanning of spectrograms: plot length 30 s, FFT length 1000, 90% overlap. Killer whale encounters were further classified into ecotypes based on the presence of ecotype-specific call types in the encounter. Call types were identified in the spectrogram window, and all calls in an encounter were examined before an encounter was attributed to a particular ecotype. Resident ecotype call types were identified from the reference catalogue of Ford 1987, transient ecotype call types were identified from a reference catalogue based on recordings published by Deecke 2003, and offshore ecotype call types were identified from a digital catalogue (J Ford, unpubl. data) collected during field encounters with photo- or genetically identified offshore killer whales.These data were recorded at SanctSound Site OC03_03 between August 02, 2020 and October 31, 2020.

This record represents killer whale sound production. Killer whale calls were detected by analysts and logged using Triton's Logger Remora. Calls were grouped into encounters, with encounters more than 30 min apart being logged as separate encounters. The following settings were used for manual scanning of long-term spectral averages: bandwidth 0-5000 Hz; 1 hour duration; and for zoomed-in scanning of spectrograms: plot length 30 s, FFT length 1000, 90% overlap. Killer whale encounters were further classified into ecotypes based on the presence of ecotype-specific call types in the encounter. Call types were identified in the spectrogram window, and all calls in an encounter were examined before an encounter was attributed to a particular ecotype. Resident ecotype call types were identified from the reference catalogue of Ford 1987, transient ecotype call types were identified from a reference catalogue based on recordings published by Deecke 2003, and offshore ecotype call types were identified from a digital catalogue (J Ford, unpubl. data) collected during field encounters with photo- or genetically identified offshore killer whales.These data were recorded at SanctSound Site OC04_04 between August 04, 2020 and December 21, 2020.

This record represents killer whale sound production. Killer whale calls were detected by analysts and logged using Triton's Logger Remora. Calls were grouped into encounters, with encounters more than 30 min apart being logged as separate encounters. The following settings were used for manual scanning of long-term spectral averages: bandwidth 0-5000 Hz; 1 hour duration; and for zoomed-in scanning of spectrograms: plot length 30 s, FFT length 1000, 90% overlap. Killer whale encounters were further classified into ecotypes based on the presence of ecotype-specific call types in the encounter. Call types were identified in the spectrogram window, and all calls in an encounter were examined before an encounter was attributed to a particular ecotype. Resident ecotype call types were identified from the reference catalogue of Ford 1987, transient ecotype call types were identified from a reference catalogue based on recordings published by Deecke 2003, and offshore ecotype call types were identified from a digital catalogue (J Ford, unpubl. data) collected during field encounters with photo- or genetically identified offshore killer whales.These data were recorded at SanctSound Site OC01_01 between March 08, 2019 and July 08, 2019.

This record represents killer whale sound production. Killer whale calls were detected by analysts and logged using Triton's Logger Remora. Calls were grouped into encounters, with encounters more than 30 min apart being logged as separate encounters. The following settings were used for manual scanning of long-term spectral averages: bandwidth 0-5000 Hz; 1 hour duration; and for zoomed-in scanning of spectrograms: plot length 30 s, FFT length 1000, 90% overlap. Killer whale encounters were further classified into ecotypes based on the presence of ecotype-specific call types in the encounter. Call types were identified in the spectrogram window, and all calls in an encounter were examined before an encounter was attributed to a particular ecotype. Resident ecotype call types were identified from the reference catalogue of Ford 1987, transient ecotype call types were identified from a reference catalogue based on recordings published by Deecke 2003, and offshore ecotype call types were identified from a digital catalogue (J Ford, unpubl. data) collected during field encounters with photo- or genetically identified offshore killer whales.These data were recorded at SanctSound Site OC04_02 between August 20, 2019 and September 05, 2019.

This record represents fin whale sound production detected from raw passive acoustic data. The Low Frequency Detection and Classification System (LFDCS) call library for fin whale 20-Hz pulses was built for the data sampled at 120 Hz. All fin whale detections with a Mahalanobis distance of 3.0 or less were manually verified for true detections. A logistic regression was applied to these results to facilitate reducing the size of the dataset that ultimately needed to be manually verified for confident species detection. This analysis revealed that a minimum number of 29 detections per time window used (hour or day) need to be detected to ensure that a fin whale was truly detected with a confidence of 90%. All days with at least 29 detections were manually verified for daily presence of fin whale 20-Hz pulses. From days with 29 or more detections, fin whales were considered present for that day if a true detection was found within a regular inter-pulse interval pattern of at least three other 20-Hz pulses. These data were recorded at SanctSound Site SB02_03 between April 02, 2019 and June 01, 2019.