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Monitoring the diurnal and seasonal foraging of Hawaiian monk seals in mesophotic rubble habitat using seafloor event loggers called "electric rocks."

Metadata Updated: March 16, 2024

Video from seal-mounted cameras fitted to Hawaiian monk seals showed that seals visited patches of loose mesophotic seafloor rock to flip them and obtain the prey hiding underneath. Diver surveys of rock patches documented 38 species of fish and invertebrates and found 38% of the larger diameter rocks (10-100 cm) flipped with the encrusted live coral and algae side left face down. We developed a set of "electric rocks" (artificial rocks fitted with event loggers) to record the date and time of any movement. We deployed the rocks in multiple clusters on the terraced slope of the seal colony atoll (French Frigate Shoals) close to the beach haulout and at two sites further away on the summits of neighboring banks. The goal was to expand temporal monitoring (diurnally and seasonally) of the seal's use of mesophotic rubble patches without requiring further instrumentation of monk seals. The data from the electric rocks showed patterns consistent with the behavior seen from the seal-mounted video, including rapid rock-to-rock searching and more movements closer to seal haulouts. The electric rocks detected more rock tips on the atoll terrace than on the banks, with higher counts seen during the day at the bank summits. Seasonally, both the terrace and bank detected more movements in summer and fall months consistent with the monk seal's reproductive pupping and molting season than during the rest of the year, suggesting some seasonal change in the foraging habitat of monk seals.

Access & Use Information

License: No license information was provided. If this work was prepared by an officer or employee of the United States government as part of that person's official duties it is considered a U.S. Government Work.

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Dates

Metadata Date February 29, 2024
Metadata Created Date September 8, 2023
Metadata Updated Date March 16, 2024
Reference Date(s) April 1, 2020 (creation), July 25, 2023 (publication)
Frequency Of Update notPlanned

Metadata Source

Harvested from NMFS PIFSC

Additional Metadata

Resource Type Dataset
Metadata Date February 29, 2024
Metadata Created Date September 8, 2023
Metadata Updated Date March 16, 2024
Reference Date(s) April 1, 2020 (creation), July 25, 2023 (publication)
Responsible Party (Point of Contact, Custodian)
Contact Email
Guid gov.noaa.nmfs.inport:70346
Access Constraints Cite As: Pacific Islands Fisheries Science Center, [Date of Access]: Monitoring the diurnal and seasonal foraging of Hawaiian monk seals in mesophotic rubble habitat using seafloor event loggers called "electric rocks." [Data Date Range], https://www.fisheries.noaa.gov/inport/item/70346., Access Constraints: NA, Use Constraints: NA, Distribution Liability: While every effort has been made to ensure that these data are accurate and reliable within the limits of the current state of the art, NOAA cannot assume liability for any damages caused by errors or omissions in the data, nor as a result of the failure of the data to function on a particular system. NOAA makes no warranty, expressed or implied, nor does the fact of distribution constitute such a warranty.
Coupled Resource
Frequency Of Update notPlanned
Harvest Object Id 7fec5b5e-867d-446a-b1be-5b6f211576d7
Harvest Source Id c0beac72-5f43-4455-8c33-1b345fbc2dfe
Harvest Source Title NMFS PIFSC
Licence NOAA provides no warranty, nor accepts any liability occurring from any incomplete, incorrect, or misleading data, or from any incorrect, incomplete, or misleading use of the data. It is the responsibility of the user to determine whether or not the data is suitable for the intended purpose.
Lineage Data on seal rock flipping behavior from the Crittercam relational database from annotated video from cameras deployed by PIFSC on French Frigate Shoals Monk Seals. Data on mean hourly wave energy (ht and period) from the CDIP Waimea buoy on the North Shore of Oahu
Metadata Language eng
Metadata Type geospatial
Progress completed
Spatial Data Service Type
Spatial Reference System
Spatial Harvester True
Temporal Extent Begin 1998-08-24
Temporal Extent End 2003-10-31

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