This study demonstrates how cold-water coralmorphology and habitat distribution are shaped by localhydrodynamics, using high-definition video from TislerReef, an inshore reef in Norway. A total of 334 videoframes collected on the north-west (NW) and south-east(SE) side of the reef were investigated forLophelia pertusacoral cover and morphology and for the cover of theassociated spongesMycale linguaandGeodiasp. Ourresults showed that the SE side was a better habitat forL.pertusa(including live and dead colonies). Low cover ofGeodiasp. was found on both sides of Tisler Reef. Incontrast,Mycale linguahad higher percentage cover,especially on the NW side of the reef. Bush-shaped colo-nies ofL. pertusawith elongated branches were the mostabundant coral morphology on Tisler Reef. The highestabundance and density of this morphology were found onthe SE side of the reef, while a higher proportion of cau-liflower-shaped corals with short branches were found onthe NW side. The proportion of very smallL. pertusacolonies was also significantly higher on the SE side of thereef. The patterns in coral spatial distribution and mor-phology were related to local hydrodynamics—there weremore frequent periods of downwelling currents on the SEside—and to the availability of suitable settling substrates.These factors make the SE region of Tisler Reef moresuitable for coral growth. Understanding the impact oflocal hydrodynamics on the spatial extent and morphologyof coral, and their relation to associated organisms such assponges, is key to understanding the past and future development of the reef

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• The effect of local hydrodynamics on the spatial extent and morphology of cold-water coral habitats at Tisler Reef,Norway