February 17, 2023 — A study led by the University of Maine captured how entire rockweed beds recover from harvest, and the practice has a smaller impact than previously thought.
Rockweed wields immense influence over its intertidal habitat. Its tangled branches form the backbone of a rich ecosystem that shelters and feeds an abundance of marine life. Everywhere rockweed grows, invertebrates, fish and fowl follow.
The marine alga has also been valued as a soil amendment for centuries, and more recently as crop biostimulants. The Maine Department of Marine Resources reports that commercial harvest has more than tripled over the past 20 years. Rockweed grows back following harvest, with biomass recovering faster than height. This change, combined with climbing harvest pressure, has led to concern regarding the practice. Harvesters, landowners, ecologists and community scientists want to understand how cutting and removing rockweed affects the ecosystem it creates.