Genetic diversity is being lost at a fast pace — seaweeds are no exception. The giant kelp, Macrocystis pyrifera, forms vast underwater forests in both hemispheres and is a key species for ecosystem functioning. But this species is also a commodity product. M. pyrifera is harvested for its chemical compounds (e.g. alginates) and for feedstock (e.g. abalone). In the past 5 years, some companies tried new farming techniques to boost biomass production for biofuel conversion. But the lack of sustainable management can lead to genetic erosion and degradation of livelihoods. Often, the natural genetic populations are not described, and we may be losing what is yet to be found. In this talk Dr Sara Barrento discusses a possible solution. This talk was presented during the International Seaweed Symposium (ISS) which took place in June 2016.