Whaling Trail Mapping

Monitoring shorefast sea ice during spring whaling at Utqiaġvik

Warren Matumeak (upper left; photo by Shari Fox) created the first known maps of Utqiagvik’s ice trails in as hand drawn maps in 2001 (example in upper right). A map of the 2001 ice trails was reconstructed based on the collection of Warren’s sketches.

Each spring Utqiaġvik hunters build trails across the shorefast sea ice to access bowhead whale hunting sites. Since 2007, the whaling community, NSB personnel, and scientists have mapped the trails to make sure they are safe for travel.

These annual surveys reveal the average thickness of level first-year shorefast ice, which is controlled by local freeze-up processes and timing, as well as weather, ocean, and ice conditions in the region throughout fall and winter.

This project was initially inspired by the efforts of Utqiaġvik elder Warren Matumeak and biologist Craig George to document the trails using GPS and hand-drawn maps in 2001.

Making the maps

One end of the instrument creates an electromagnetic field. Since saltwater conducts electricity the EM meter causes a secondary electromagnetic field in the water. The opposite end of the EM meter measures the strength of this secondary field which depends on the distance between the instrument and the water. As the instrument is pulled over trail sections with thick ice (ice does not conduct electricity) the secondary signal is weaker because the distance to the water is greater. Across sections with thin ice the signal is stronger because the distance is smaller.

Oliver Dammann pulling the EM instrument along an ice trail in spring 2015.

The team maps trails using GPS, and continuously measures ice thickness. This information is added to a map with radar imagery showing the general ice type. Maps are provided to the community in paper and electronic formats during the hunting season (late April–late May).

For more information

AAOKH supports scientists Matt Druckenmiller and Josh Jones to continue this important work. Questions? Contact Matthew Druckenmiller, National Snow and Ice Data Center.

Related publications and resources

This work is a partnership with University of Alaska Fairbanks and the National Snow and Ice Data Center, field support from Ukpeagvik Inupiat Corporation