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Elkhorn Slough sea otter data related to volunteer science


Wasson, Kerstin; Yee, Julie (2022), Elkhorn Slough sea otter data related to volunteer science, Dryad, Dataset,


Four CSV files with data from basic field surveys of southern sea otters in Elkhorn Slough estuary, central California, USA are provided.  These are the data used to generate Figures 4-11 in Eby et al. 2022 publication in Ecosophere.  The data almost entirely consist of otter counts conducted by visual surveys; one file also contains data on the percentage of otters observed foraging.  Complete description of the study objectives, methods, field sites, and uses of these data for analyses and interpretations can be found in Eby et al. 2022.


The Otter_Elkhorn_LongTerm dataset consists of data from three sources, 1) ecotourist counts from the Elkhorn Slough Safari boat, 2) volunteer observations from the Elkhorn Slough Reserve Otter Monitoring Program, and 3) annual range-wide surveys coordinated by USGS.  For the latter, we used only otter counts from the lower Elkhorn Slough estuary. USGS southern sea otter data are made available annually, e.g. for 2019 here:  These publically available data emphasize the value of 3 year running averages for larger regions, while the dataset archived here has annual counts just for the local Elkhorn Slough estuary. The other three datasets represent data collected by volunteers for the Reserve Otter Monitoring Program.  Description of field data collection methods are in the Eby et al. 2022 Ecosophere paper.

Usage Notes

These are CSV files; no special programs or software required.