Líffræðifélag Íslands - biologia.is
Líffræðiráðstefnan 2019

Erindi/veggspjald / Talk/poster E68

The Atlantic rock crab: Post-invasion demography and persistence in Iceland

Höfundar / Authors: Sindri Gíslason (1), Snæbjörn Pálsson (2), Hermann Dreki Guls (3), Jörundur Svavarsson (2), Jónas Páll Jónasson (4), Halldór P. Halldórsson (3)

Starfsvettvangur / Affiliations: 1. Náttúrustofa Suðvesturlands, 2. Háskóli Íslands, 3. Rannsóknasetur Háskóla Íslands á Suðurnesjum, 4. Hafrannsóknastofnun

Kynnir / Presenter: Sindri Gíslason

With the increase in global oceanic trade the establishment of non-indigenous marine organisms has become a major environmental and economic problem worldwide. In 2006, the Atlantic rock crab (Cancer irroratus) was reported in Icelandic waters. This is the first record of this relatively large crab species outside its natural range, i.e. the east coast of North America. The crab was most likely transferred to Iceland as larvae in ballast water and has successfully established a reproducing population in Icelandic waters. The species has now spread clockwise around the country along the southwestern coast to the east coast, colonizing more than 70% of the coastline. Our studies show that the rock crab is now established in the Icelandic coastal ecosystem. The crab is abundant on soft bottom substrates, found in density up to 0.5 crabs/m2 which is among the highest abundance documented for the species in its native areas. The green crab (Carcinus maenas) and the spider crab (Hyas araneus) are the only native brachyuran decapod species commonly found in its new habitat, but despite its recent colonization the rock crab was the most abundant brachyuran in the areas studied in southwest Iceland. The size and abundance of adult crabs, their reproductive conditions, and occurrence of all larval stages, indicate that the Atlantic rock crab has successfully colonized Iceland. Whether it is due to favourable environmental conditions, food availability and/or lack of predators and competitors remains to be seen.