of the lough are dominated by the seaweed knotted wrack Ascophyllum nodosum. The usual zonation of weeds on these shore is, at the top channel wrack (Pelvetia canaliculata (L.) Dcne. et Rhur.), followed by spiral wrack (Fucus spiralis L.), then knotted wrack (Ascophyllum nodosum (L.) Le Jol) with some admixture of bladder wrack (Fucus vesiculosus) L. and then serrated wrack (Fucus serratus L.) before coming to the low water kelps. Other algae include: Fauna Strangford Lough and Islands is an Important Bird Area. Strangford Lough is an important winter migration destination for many wading and sea birds. Animals commonly found in the lough include common seals, basking sharks and brent geese. Three quarters of the world population of pale bellied brent geese spend winter in the lough area. Often the numbers are up to 15,000. The Castle Espie wetland reserve sits on the banks of the lough near Comber. The invasive carpet sea squirt, Didemnum vexillum, was found in the Lough in 2012. Tidal electricity In 2007 Strangford Lough became home to the world's first commercial tidal stream power station, SeaGen. The 1.2 megawatt underwater tidal electricity generator, part of Northern Ireland's Environment and Renewable Energy Fund scheme, took advantage of the fast tidal flow in the lough which can be up to 4 m/s. Although the generator was powerful enough to power up to a thousand homes, the turbine had a minimal environmental impact, as it was almost entirely submerged, and the rotors turned slowly enough that they pose no danger to wildlife. In 2008 a tidal energy device called Evopod was tested in Strangford Lough near the Portaferry Ferry landing. The device was a 1/10 scale prototype, monitored by Queen's University Belfast. The device was a semi-submerged floating tidal turbine, moored to the seabed via a buoy-mounted swivel. The scale device was not grid connected. Sports In July 2016, the Strangford Lough and Lecale Partnership, Scottish Coastal Rowing Association, Newry, Mourne and Down District Council and Ards and North Down Borough Council hosted the "Skiffie Worlds 2016" rowing championships. The event was attended by 50 clubs from Scotland, England, Northern Ireland, the Netherlands, The United States, Canada and Tasmania. Racing was held over a 2 km course on Strangford Lough at Delamont Country Park. Ferry The Portaferry–Strangford ferry service has linked Portaferry and Strangford, at the mouth of the Lough, without a break and for almost four centuries.