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The Seward Line is a 130 nautical mile transect extending into the Alaskan gulf. For 20 years, scientists have been using this line to monitor the marine ecosystem.

The USFWS research vessel M/V Tiglax travels the entire transect twice a year. Along the way, samples of water and organisms are collected.

These help build an understanding of the seasonal cycles and longer-term changes in environmental conditions and biological productivity in the Gulf.

Tenure Chasers’ photographer Anne-Lise Ducluzeau sailed the Seward Line in September 2016, assisting with sampling for her own research projects and creating a series of beautiful images.

Check out the full gallery.