A modelled global distribution of the kelp biome

Kelp, seaweeds of the order Laminariales, are of ecological and conservation importance because they form undersea forest habitat for many varieties of fauna and flora including mammals, and commercial fish species. In the absence of a world map of the kelp biome, we predicted its potential distribution using geographic records and environment variables in a MaxEnt model. This estimated that the kelp biome occupied 1,469,900 km2 and was present on 22% of the world's coastline. While average sea surface temperature was the most important environmental variable for the biome across all species, wave height, distance from the coast and minimum temperature were of most importance for individual species. This map can be used in planning where marine reserves should be best located, modelling the effects of climate change, and in estimating the blue (ocean) carbon storage. Current field observations should confirm the presence of kelp within the modelled biome, and if absent consider if human impacts, including climate change, are to blame.