Gwennap Head identified steamships were wrecked, stranded or sank in the area. There have been none since 1923. The navigation markers feature as "the Cones of Runnel" in Hammond Innes's 1940 thriller "The Trojan Horse". Gwennap Head is part of the Porthgwarra to Pordenack Point Site of Special Scientific Interest (SSSI) designated for its vegetation of waved maritime heath, and for being of considerable ornithological interest; especially for passage migrants. It is renowned for its relative abundance of passing marine bird species with many common species such as northern gannet ("Morus bassanus"), Manx shearwater ("Puffinus puffinus"), common guillemot, ("Uria aalge"), razorbill ("Alca
Great shearwater Great shearwater The great shearwater ("Ardenna gravis"; formerly "Puffinus gravis") is a large shearwater in the seabird family Procellariidae. "Ardenna" was first used to refer to a seabird by Italian naturalist Ulisse Aldrovandi in 1603, and "gravis" is Latin for "heavy". The great shearwater's relationships are unclear. It belongs in the group of large species that have been separated as genus "Ardenna" (Penhallurick & Wink 2004); within these, it might be allied with the other black-billed, blunt-tailed species, the short-tailed shearwater and especially the sooty shearwater (Austin 1996, Heidrich "et al." 1998). Alternatively (Austin 1996, Austin "et al." 2004), it