The Secret Life of Icelandic Goats: Activity, group structure and plant selection of the Icelandic goat

• Main Author: Hrafnhildur Ævarsdóttir 1986-
• Other Authors: Háskóli Íslands
• Format: Thesis
• Language: English
• Published: 2014
• Subjects: Líffræði; Geitur; Brennistaðir; Háafell; Iceland
• Online Access: http://hdl.handle.net/1946/18584

Farm animals are social with a strong tendency to form groups of various sizes. Goats form dynamic foraging groups in response to local environmental conditions and habitat characteristics. Lives of group living animals are divided into periods of rest and activity which results in a compromise between optimal foraging, social activities and environmental constraints. Goats and other free-ranging ruminants spend most of their time foraging and moving around pasture. Goats have been described as intermediate mixed feeders and are known to be highly flexible in their foraging selection. The objectives of this study were to (i) assess the nature of the social structure of the biggest goat herd in Iceland (N = 186 adult goats) at Háafell Farm (pasture size 200 ha), (ii) to obtain information on the activity budget of this herd and to compare it with a smaller, more confined herd at Brennistaðir Farm (pasture size 1.6 ha), and (iii) to investigate plant selection and pasture utilization of a free roaming goat herd in Iceland. This study strongly supports a fission-fusion group type among goats. Results show that formation of groups seemed neither to be based on kinship nor age as no significant correlation was found between bonded individuals and these variables. Mean group size in the large herd was found to be 5.3 in August and 6.1 in September and skewed towards 1 – 5 individuals. Number of groups was highest in the middle of the day and most foraging groups were found at 40 – 60 m above sea level, typically around the farm. Distribution of groups was found to be random in all but two cases (N = 64 scans). The goats were found to utilize most of the area but one small region (10%) was noticeably less used without any obvious reasons, as it did not differ from others. The goats spent from 20 to 90% of their time foraging, a behaviour pattern that was influenced by weather conditions. Typically they spent 40 – 60% of their time foraging but the big herd spent significantly more time foraging than the small more ...