Monitoring Body Condition of Seals in Alaska Using Small UAS

The recent and rapid environmental changes in the Subarctic and Arctic due to a warming climate have increased concern about the health, ecology, and abundance of pinniped populations in the region. Ice-associated seals (bearded (Erignathus barbatus), ringed (Pusa hispida), spotted (Phoca largha), and ribbon (Histriophoca fasciata)) are key components of subarctic and arctic ecosystems in Alaska, and long-term monitoring has indicated that the body condition of some of these populations has declined in recent decades. Traditional methods of capturing and measuring individuals to assess body condition of these populations are challenging and constrained by small sample sizes; therefore, our goal was to develop a method to expand the numbers of individuals that can be monitored. We used an uncrewed aerial system (UAS) to collect imagery of bearded, ringed, and spotted seals at captive care facilities, and used photogrammetry of the UAS images to develop a model to estimate body mass to use as an indicator of body condition. We collected measurements from the UAS images, which were taken with the UAS directly over the seals with the camera at nadir.

To demonstrate that a UAS can operate and collect images of ice-associated seals in arctic conditions, and that photogrammetry of the imagery can be used to estimate body mass, potentially increasing the number of seals of these populations that can be assessed for body condition.

The details of this project and how the data were processed and analyzed can be found in our Final Report for the NOAA ORTA Bridging Program Project: An Extension of 2020-05 Monitoring Body Condition of Seals in Alaska Using Small UAS, which can be found here: https://repository.library.noaa.gov/view/noaa/69885.

Data and code for reproducing the analysis is available at https://github.com/noaa-afsc/bodyConditionUAS and will be published on Zenodo upon acceptance. Once the archival process is complete and verified, the data set will be publicly available. Acknowledge NOAA/NMFS/AFSC as the source from which these data were obtained in any publications and/or other representations of these data. Communication and collaboration with dataset authors is strongly encouraged prior to use.

Data are available for download from https://github.com/noaa-afsc/bodyConditionUAS.

There are no data access constraints.

User must read and fully comprehend the metadata prior to use. Applications or inferences derived from the data should be carefully considered for accuracy. 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 any 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. Acknowledge NOAA/NMFS/AFSC or the specified citation as the source from which these data were obtained in any publications and/or other representations of these data. The Alaska Fisheries Science Center should be acknowledged as the data source in products derived from these data. Communication and collaboration with dataset authors is strongly encouraged.

There are no metadata access constraints.

Metadata are subject to revision at any time and information within the metadata record should not be cited without author consent. While every effort has been made to ensure that these metadata are accurate and reliable within the limits of the current state of the art, NOAA cannot assume liability for any damages caused by any errors or omissions in the metadata. NOAA makes no warranty, expressed or implied, nor does the fact of distribution constitute such a warranty.