Imagery and elevation models monitoring algae at intertidal sites on Northwest Calvert Island - 2017

Orthomosaics of long-term intertidal monitoring sites on NW Calvert Island were created using unoccupied aerial systems (UAS). Subsequently, a digital elevation model and elevation point cloud were generated for each site. Imagery was captured for each site with a DJI Phantom 3 Pro UAS. The survey design followed a grid pattern to ensure coverage of the entire study area with a minimum 80% overlap between images. To geolocate the images, 6-10 ground control points were surveyed with a Topcon GR-5 real-time kinematic (RTK) GPS. Near infrared imagery(NIR) was also captured at the North Beach site with a MAPIR Survey 2 camera. The MAPIR is a low-resolution modified camera that captures imagery in the NIR and Red bands. The camera is mounted to the Phantom 3 and operated manually. The MAPIR images are processed to create an imagery mosaic with Pix4D. The imagery is then radiometrically calibrated using the empirical line method with grey and white targets. A spectroradiometer has NOT been used to assess the accuracy of the imagery calibration. The difference vegetation index (DVI) is calculated to remove the effects of illumination, and to emphasize vegetation signatures. The DVI is calculated as NIR-R. For a specific list of sites, see the attached documentation.

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Access and Use

Licence: Appropriate credit must be given to Hakai Institute and the authors of the dataset.

Data and Resources


Metadata Reference Date(s) March 26, 2021, 22:20 (UTC) (Lastupdate)
Dataset Reference Date(s) May 04, 2017 (Creation)
December 19, 2017 (Publication)
Frequency of Update As Needed


Dataset extent

Map data © OpenStreetMap contributors

Additional Info

Field Value
Ocean Variables Other
Scope Dataset
Status On Going
Topic Category
  • biota
  • oceans
Maintenance Note
Point of Contact
  • Name: Hakai Geospatial Technology Team
    Affiliation: Hakai Institute
    Contact Info Email:
    Role: Point of Contact
  • Name: Hakai Geospatial Technology Team
    Affiliation: Hakai Institute
    Contact Info Email:
    Role: Point of Contact
Responsible Party
  • Organisation Name / Affiliation: Hakai Institute
    Contact Info Email:
    Role: Resource Provider
Spatial Extent {"type": "Polygon", "coordinates": [[[-128.157577515, 51.6435896861], [-128.089599609, 51.6435896861], [-128.089599609, 51.6802193779], [-128.157577515, 51.6802193779], [-128.157577515, 51.6435896861]]]}
North Bounding Latitude 51.68021937787972
South Bounding Latitude 51.64358968607138
East Bounding Longitude -128.089599609375
West Bounding Longitude -128.15757751464844
Temporal Extent
Vertical Extent
Default Locale English
Citation identifier