Tricellaria inopinata d’Hondt and Occhipinti-Ambrogi, 1985

Kakkonen, Jenni E., Worsfold, Tim M., Ashelby, Christopher W., Taylor, Andrea & Beaton, Katy, 2019, The value of regular monitoring and diverse sampling techniques to assess aquatic non-native species: a case study from Orkney, Management of Biological Invasions 10 (1), pp. 46-79 : 61

(11) Tricellaria inopinata d’Hondt and Occhipinti-Ambrogi, 1985

Status in U.K. – non-native.

The bryozoan Tricellaria inopinata has been recorded each year since 2014 from scrape, settlement panel and rapid assessment samples. It has been found at Gutter Sound and The Grinds navigation buoy, Stromness and Kirkwall marina and in Fersness Bay and Pierowall visiting yacht moorings.

Cook et al. (2013) document the European distribution of T. inopinata demonstrating a wide U.K. range along southern and western coasts as well as eastern Scotland. The first Scottish records were made in 2006 from marinas in Troon and Clyde and it has since been recorded in eight other marinas in Scotland ( Cook et al. 2013). Its occurrence in marinas indicates that recreational yachting may play a role in the dispersal of this species but Bishop et al. (2015b) also note that it is present on natural shores indicating natural dispersal on a more localised scale probably also occurs. Cook et al. (2013) did not include any northern Scottish marinas in their review of the Scottish distribution of T. inopinata but it was recorded from Orkney in August 2012 by Nall et al. (2015). The species is probably of Pacific origin (possibly NE) but its precise native range remains uncertain ( Dyrynda et al. 2000; Cook et al. 2013).