Giant kelp is not a plant, but a large seaweed that acts as a foundational species, creating underwater forests similar to trees on land. Anatomically, it anchors to the sea floor using a 'holdfast', extends vertically via a stem-like 'stipe', and captures sunlight with leaf-like 'blades' kept afloat by gas bladders. These forests can grow up to 30 meters tall at a rate of 50 centimeters per day, providing critical habitat for rock lobsters, fish nurseries, and marine mammals. However, in eastern Tasmania, these ecosystems are now an endangered marine community, having suffered a 95% decline. This catastrophic loss is driven primarily by climate change, specifically increasing sea surface temperatures and the resulting lower nutrient levels in the water.
Government and university research bodies in Australia monitor marine ecosystem health and track the impacts of climate change on coastal waters.
Restoration efforts led by the Australian National Algae Culture Collection focus on the microscopic life stages of the kelp. Scientists collect cuttings from wild kelp blades, which release spores. These spores develop into microscopic male and female gametophytes. In the lab, these gametophytes are kept in culture under controlled light wavelengths and temperatures. This allows scientists to keep the kelp in 'stasis', grow more cells for study, or trigger the production of eggs and sperm to create juvenile kelp (sporophytes). These 'baby' kelp, which look like tiny leaves, are grown for about three months until they reach approximately two centimeters in length, at which point they are ready to be planted out into the ocean.
Australian biological collections and taxonomy databases provide essential resources for understanding the life cycles and classification of marine algae.
To ensure the long-term survival of giant kelp forests, scientists are utilizing genomics to identify specific strains that are naturally more tolerant to warmer waters. By analyzing the genetic structure of remnant populations, researchers can understand the genetic diversity and connectivity between different kelp groups. This work supports the establishment of a biobank—effectively a 'seed bank' for seaweed—to conserve this genetic diversity. The goal is to select warm-tolerant strains for replanting, giving the restored forests the best chance to thrive despite ongoing climate changes. This complex project involves collaboration between CSIRO, The Nature Conservancy, the University of Tasmania, and Google.
Conservation organizations and research institutes in Australia collaborate to fund and execute large-scale reef and marine forest restoration projects.