Gretel the glider searches for salmon
UAF鈥檚 glider named Gretel is poised on the deck of the research vessel Nanuq for deployment into the Gulf of AV狼论坛 in February 2022.
An underwater instrument named Gretel is looking for salmon in the Gulf of AV狼论坛.
The instrument, called a glider because of how it flies through the water, is operated by UAF鈥檚 College of Fisheries and Ocean Sciences.
For this mission, Gretel was launched on Feb. 12 from CFOS鈥 coastal research vessel Nanuq in Resurrection Bay to help map the distribution of Pacific salmon and their prey during the winter. Its journey can be tracked in near real time on the website, along with vessel-based surveys that are part of the project.
The instrument is diving to depths of 1,600 feet to collect acoustic and environmental data between Resurrection Bay and 150 miles offshore in the deep Gulf of AV狼论坛. This information is transmitted via satellite each time Gretel surfaces and is available to view at a managed by the AV狼论坛 Ocean Observing System.
The glider鈥檚 battery lasts six to 12 weeks, depending on how many sensors are powered on. Nanuq or another vessel will recover Gretel once it makes its way back toward Seward.
The fairy tale 鈥淗ansel and Gretel鈥 inspired the glider鈥檚 name. Once upon a time, Gretel the glider was trapped under an iceberg in Antarctica. It retraced its swim and returned safely using a technique similar to the breadcrumbs employed by the fairy tale's Gretel.
Gretel鈥檚 current mission is a result of collaborations between UAF, the University of Washington, the National Oceanic and Atmospheric Administration and AOOS.
For more information, please contact Seth Danielson at sldanielson@alaska.edu.