For thousands of years, the Tlingit people have fostered systems of science and education indigenous to their home, allowing each clan to maintain stewardship of their lands. For generations, this traditional way of life brought prosperity to the Southeast Alaska communities. Many rely on the continued availability of wild seaweed harvesting, particularly of intertidal species.

Today, environmental changes threaten the preservation of this traditional lifestyle. Due to the immense weight of glaciers, which data show are melting at an increasing rate, the land in some parts of Southeast Alaska is rising up to three centimeters per year. While this might seem small, seaweeds found along the shoreline are particularly sensitive to these changes.

Justina Starzinsky-Hotch, a teacher in Klukwan, observed these stressors and asked if wild populations of Devaleraea mollis (red ribbon seaweed) and Palmaria hecatensis (stiff red ribbon seaweed) are likely to be affected. These two intertidal red seaweeds have been harvested for generations by members of the Chilkat Indian Village and the Chilkoot Indian Association. She was also interested in the potential to grow these culturally important species indoors year-round as a teaching tool.

To address these questions, University of Alaska Fairbanks assistant professor Schery Umanzor and graduate student Muriel Dittrich decided to learn more about the growth patterns of local seaweeds. The team first gathered wild seaweed alongside local harvesters and representatives of Tribal governments in the region to learn more about their interest in growing the seaweeds.

“Through those conversations, we learned about differing views regarding seaweed loss, and concerns about environmental changes and human impacts,” Umanzor explained. “In response to the views expressed, we decided to focus our study on the biology of the targeted seaweeds.”

Umanzor and Dittrich are working closely with members of the Chilkat Indian Village and the Chilkoot Indian Association to measure the status of the two intertidal seaweeds. The research team worked to grow these species outside of their natural habitat to understand their biology better.

“In the wild, seaweed survival depends on temperature, light availability, and nutrients,” said Dittrich. “Getting the right combination of these factors in an artificial setting is no simple task. This is especially difficult with red seaweeds because they are sensitive to environmental changes.”

Dittrich was successful in building individualized growing protocols for both species. At Starzinsky-Hotch’s request, educational posters of these seaweeds’ life cycles were developed and sent to the Klukwan school, Chilkat and Chilkoot tribal governments.

“The initial funding from Alaska Sea Grant was key to launching research on how environmental change may affect Devaleraea mollis and Palmaria hecatensis,” said Umanzor. “It enabled collaboration with Tribal communities, including traditional seaweed harvesters, as well as experiments to optimize these seaweed growth outside natural habitats. This work paved the way for ongoing studies on seaweed biology, sustainability, and nutritional changes. ”Since the initial research project funded by Alaska Sea Grant, Umanzor’s work with the community has shifted and expanded as part of the Alaska EPSCoR Interface of Change project. New research focuses on tracking changes in the nutritional composition and metabolism of both seaweeds. Results will help researchers and community members explain variables such as changes in protein content and seaweed flavor over time.

Alaska Sea Grant

  Alaska, biology, seaweed