Líffræðifélag Íslands
Líffræðiráðstefnan 2015
Erindi/veggspjald / Talk/poster E22
Mariana Tamayo (1), Guðmundur Halldórsson (2)
1. University of Iceland, 2. Soil Conservation Service of Iceland
Kynnir / Presenter: Mariana Tamayo
Tengiliður / Corresponding author: Mariana Tamayo (mlt@hi.is)
"In the last century the number of introduced arthropod herbivores has increased and the dynamics of insect herbivores have changed in Iceland. Several Icelandic moth species, including the red-backed cutworm (Euxoa ochrogaster), have expanded their host range to introduced species such as Nootka lupine (Lupinus nootkatensis). Although the red-backed cutworm seems to feed on various native and introduced plants and is found throughout Iceland, its herbivory and distribution are not well understood. We addressed these data gaps by assessing during the summer of 2015 the distribution of the red-backed cutworm in southern Iceland associated with Nootka lupine (introduced host) and lyme grass (native host; Leymus arenarius). Also, we monitored the presence of male adults in 2 rutabaga (introduced host, Brassica napobrassica) field crops, where the red-backed cutworm has been an agricultural pest. We found red-backed cutworm larvae and male adults in 9 sites across southern Iceland. Larval abundance ranged from 1 to 22 larvae per site, with the highest numbers seen on Nootka lupine sites near Þorlákshöfn. The number of male adults peaked in mid-August, and they were most abundant in the rutabaga field crops and in Nootka lupine and lyme grass sites near Þorlákshöfn and Eyrabakki. Overall, the area between Þorlákshöfn and Eyrabakki seems to be a hot spot for red-backed cutworm distribution and herbivory on both native and introduced host plants."