Drifting macrophytic algae increased habitat complexity in coastal waters of California, USA, especially in convergence zones. Algae are large and abundant structures, especially drift Macrocystis pynfera (0.2 to 20 m long), and have been ignored in historical models of the pelagic envi- ronment. Drift plants redistribute small fish and invertebrates, and their movement (by wind and oceanographic features) can provide insight to the movements of meroplankton. The drift of whole M. pyrifera plants is also relevant to under- standing the demography of kelp forests, whilst the drogue- like qualities of plants can be used to study oceanographic features. The pelagic environment, therefore, is characterised by a hierarchy of structures (0.05 mm to > 10 m, marine snow to drift algae) and plankton, of different sizes.