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We explore how herd composition and management factors correlate with frequencies of social interactions in horse groups. Since the welfare of horses correlates with low aggression levels and social contact opportunities, information of this kind is important. The data are a collection of records of social interactions of 426 Icelandic horses in 20 groups of at least eight horses. The complexities and limitations of the data prohibit useful statistical modelling so the results are presented descriptively. Interesting and informative patterns emerge which can be of use both in management and in future studies. Of special interest are the low levels of agonistic behaviours in breeding groups where one stallion was present. The horses were less agonistic when in groups with young foals and where group membership was stable. Unfamiliar yearlings in peer groups were especially aggressive. Allogrooming was most frequent in groups with relatively more young horses and in unstable and small groups. Interestingly, the horses allogroomed more if they had few preferred allogrooming partners. The findings show that composition (age/sex) and stability of groups are of great importance with respect to aggression levels and opportunities for establishing bonds.

The effect of land-based seal watching on the haul-out pattern of harbour seals (Phoca vitulina) was investigated between June and August of 2008–2010 on Vatnsnes, NW Iceland. The results showed that the behaviour and spatial haul-out pattern of seals was affected by the tourists. In 2009 the seals were more likely to be vigilant during periods when tourists had access to the area, compared to a period when tourists were not allowed in the area. Also, in 2010 the likeliness of the seals being vigilant increased as the number of tourists in the area increased. In addition, seals were more likely to be vigilant when tourists behaved in an active way. During the post weaning period, which coincided with the peak of the tourist season, a significantly higher proportion of seals hauled out on the skerry located farthest away from land, compared to a skerry closer to land. Seals also preferred to haul out further away from land when the number of tourists in the area increased. Single tourists and couples behaved more passively compared to families and tourist groups of more than two adults. All tourist group types were significantly more active in an approaching zone than in the seal watching zone. Education of tourists, for example through a code of conduct built on these results, is advisable to minimise disturbance of seals in the area.

Whimbrels Numenius phaeopus are waders which exhibit no plumage difference between the sexes but some sexual size dimorphism exists, with females being on average larger than the males. During two breeding seasons in Iceland, 50 Whimbrels of the islandicus subspecies were caught on nests, measured and feather samples collected for DNA sexing. Generalised linear models were used to determine the utility of biometric data to sex the birds. Wing length and body mass were the only components that contributed significantly to the final model, which correctly predicted the sex of 76% of the birds sexed by DNA with at least 95% certainty.

The Icelandic goat is an indigenous breed, descendant of goats brought to Iceland by Nordic and Celtic settlers in the 9th century (Adalsteinsson 1981). The population is estimated to have been below 1000 individuals for centuries and critically threatened at least twice. Today about 900 goats are found all over the country, mostly in small groups with one large herd located in west Iceland. Very few studies have been conducted on the Icelandic goat. Previously, only one study (on population genetics) has been published (Baldursdottir et al. 2012). The aim of the present study was to shed light on the plant selection and foraging behaviour of the largest goat herd in Iceland.

Earlier research indicates that stallions may supress interactions of their harem members, leading to less stable hierarchies and friendship bonds in harems compared to non-stallion groups. In this paper, the effect of the presense of a stallion on the social behaviour of mares was studied by comparing six harems containing stallions to four mixed sex groups not containing stallions. Both temporary and permanent harems were studied, giving the possibility to investigate the effect of group stability on social interactions. A significant linear hierarchy was found in all non-stallion groups that were used for comparison, while the hierarchies were only found to be linear in three of the six harems containing stallions (Landaus h ′, p t -test, p G -test, p p

Social dynamics and maintenance of social cohesion were studied by analysing social interventions in two groups of horses consisting of adult mares, their offspring, adult geldings and sub-adults. The animals were observed for a total of 1316h. All relevant dyadic and triadic social interactions, including initial behaviour, possible intervention and outcome, were recorded. The main question was: do horses use interventions in affiliative interactions to safeguard their social network? Horses were significantly more likely to intervene in allogrooming or play interactions that involved a preferred partner. The stronger the preferred association in allogrooming, the higher the likelihood the intervener took over allogrooming with an initial dyad member. Interveners originating from two newly introduced groups ( n =3 and 5), intervened significantly more often when a member of their own group allogroomed with an unfamiliar horse. In play, no correlation with unfamiliarity was found. Overall, the intervening horses stopped more than half of the initial allogrooming interactions, and a third of all interactions. Therefore, social facilitation cannot sufficiently explain interference behaviour. This study shows that maintaining relationships with preferred partners is important to horses and has implications for equine husbandry and management.

Behaviour and location of individuals in five groups ( N = 10; 19; 23; 28; and 30) of Icelandic horses kept in large pastures was documented to see if rank position influenced access to hay and shelter in the wintertime. Rank orders were significantly linear in all groups and correlated with both age and weight in four of the five groups. The higher ranking horses spent relatively more time than the subordinates eating hay and less time grazing, while the total time spent eating was the same. The subordinate horses were more likely to be found at the periphery of their respective groups than the dominant ones. Only one group, which consisted almost exclusively of sub-adults, did use the manmade shelter to some extent. In the more established groups (older horses) higher ranking individuals got shelter from the others when the horses stood in tight groups during windy days. Our results in general suggest that group composition can be of much significance with respect to access to both food and shelter. In the two groups where body condition was assessed the horses which had higher ranks improved their condition over the winter while the opposite was true for the low ranking ones.

We studied sex differences in the nature of aggression and dominance behaviour in two newly formed groups of 1-year-old Icelandic horses. One herd contained nine geldings, the other nine mares. The groups were matched with regard to dominance-determining traits such as age, weaning age, composition of native herd, social experience, genetic origin, body condition and maternal dominance status. High-ranking individuals of both sexes were more aggressive, high-ranking males were older, and high-ranking females had a better body condition. Frequencies of aggressions were similar in both groups. The mares reacted significantly more by showing submission upon an aggression rather than by not responding or by escalating the aggression. For the geldings, this difference was not observed due to a lower tendency to submit. A linear dominance hierarchy was found in both groups. David's scores provided additional information regarding cardinal rank distances and were used to calculate steepness of hierarchies. The female hierarchy was somewhat steeper compared to the male hierarchy, suggesting somewhat lower despotism among males. This was mainly a consequence of the lower unidirectionality in male submission. Male contests occurred predominantly between dyads at top and mid positions, suggesting a low degree of acceptance of the hierarchy.

Distinct preference of species for habitats is most often driven by long term differences in demographic rates between habitats. Estimating variation in those rates is key for developing successful conservation strategies. Stochastic events can interact with underlying variation in habitat quality in regulating demography but the opportunities to explore such interactions are rare. Whimbrels in Iceland show a strong preference for sparsely vegetated riverplains. Such habitats in Iceland face various threats, e.g., climate change, river regulation and spread of alien plant species. In this study we compared demographic parameters of breeding Whimbrels between riverplains and other habitats before, during and after volcanic eruption events to estimate the importance of the habitats for the species and the effect of ash deposit on breeding success. We found that an estimated minimum of 23% of the Icelandic population of Whimbrels and c. 10% of the world population of the species breed in riverplain habitats in Iceland. Whimbrels bred consistently at much higher densities in riverplain habitats than in other habitats and riverplains also had higher densities of pairs with fledglings although the proportion of successful breeders was similar between habitats. Predation by livestock may have had a considerable negative effect on breeding success on our study sites. Breeding was negatively affected by the volcanic activity, probably through the effects of ash on the invertebrate food supply, with breeding success being gradually worse closer to the eruption. Breeding success was equally affected by volcanism across habitats which differed in underlying habitat quality. This study gives an example of how populations can be regulated by factors which operate at different spatial scales, such as local variation in habitat quality and stochastic events which impact larger areas., University of Iceland Research Fund, Icelandic Research Fund for Graduate Students, Palmi Jonsson‘s Conservation Fund

This article considers the knowledge students (ages 6, 10, and 15 years) have of animals from a cross-cultural perspective. Students from six countries (Brazil, England, Finland, Iceland, Portugal, and the United States of America) were asked to free-list as many animals as possible and state where they had seen or learned about the animals. The results were analyzed and they indicate that 1) Students are aware of animals. 2) Students are more aware of mammals as examples of animals. 3) There is a globally shared folk biological knowledge of animals. 4) Students learn about animals during socio-cultural interactions. The educational implications are discussed., CIEC – Research Centre on Child Studies, UM (FCT R&D 317)

1 Spatial and temporal variation in body size of yellow dungflies, Scatophaga stercoraria, gathering on and around cow droppings was studied in an Icelandic population in order to elucidate the effect of male and female size on male mating tactics. 2 Males copulating on droppings were on average larger than males copulating in the grass, but of similar size to males guarding ovipositing females. Males searching on droppings were smaller than males copulating or guarding females on droppings but larger than males copulating in the grass. No such differences were found in female size. 3 Resource-holding power of males (RHP, i.e. male: female size ratio) differed between the three mating groups and was highest for males on the droppings. Size and RHP clearly affect the tactics of copulating males. Males with low RHP tend to copulate in the grass in spite of the cost of longer copulation duration. We argue that this is caused by risk of takeovers from large searching males. 4 There was no change in male size with the age of individual droppings. Contrary to what might be expected, large searching males are not predominantly found at fresh droppings when the probability of catching unpaired females is highest. We suggest instead that good prospects in taking females over from other males must make the strategy to search for females on older droppings profitable. 5 RHP did not change with age of dropping in the three mating groups. The size of ovipositing females increased with age of dropping, probably reflecting longer copulation and egg-laying times of large females. 6 We found an overall positive relationship between sizes of male and female partners. This correlation was highly significant for copulating pairs in the grass. This is probably a consequence of males with low RHP copulating in the grass and fights in which larger males take over females from smaller males. A weaker, but significant, correlation was found amongst ovipositing pairs. This must be due to take-over effects. No size correlation was found for pairs copulating on droppings.

Group dynamics and the social behaviour of mares were investigated in the periods before and after foaling during two non-consecutive years, in a herd of Icelandic horses consisting of adult mares and geldings and juvenile fillies, geldings and colts. The horses were observed 24 h a day for 5–6 weeks; i.e. a total of 1483 h. There were significant changes in the social behaviour and interactions of mares after foaling, compared both to their own behaviour pre-partum and to that of barren control mares. While the frequency of allogrooming dropped during the study period in all mares, it dropped significantly more in foaling than in control barren mares. However, while the absolute allogrooming frequency was strongly correlated with reproductive state, it was still remarkably consistent within an individual adult mare between the study years. After foaling, mares with foals separated off into a distinct subgroup, whereas barren control mares increased interaction with the rest of the herd; it is presumed that separation served to keep the foals at a safe distance from the more boisterous geldings and sub-adults; alternatively, it could have been the result of mutual attraction between the foals. In general, the linear dominance order was correlated strongly with age, and the top-ranking mares were older mares that had not yet begun a senescent loss of physical condition which resulted in a later slight drop down the hierarchy. There was no consistent relationship between dominance rank and the pattern of preferred recipients of affiliative interactions, while familiarity was a more important determining factor than kinship in the selection of a preferred partner for affiliative interactions. The preferred partner for proximity was often the same individual as that for allogrooming, suggesting that proximity was a result of an active process rather than of passive acceptance. The presence of adult geldings in the herd did not seem to change the social behaviour of mares as compared to that described for feral horses, and did not appear to negatively affect behaviour during parturition, mare-foal bonding or subsequent maternal care. In short, maintenance of breeding mares in a herd of mixed age and sex did not interfere with normal species-specific behaviour or with the development of the stable, long-lasting mare–mare bonds that are central to maintaining a stable herd. It is concluded that such a system could be a welfare-friendly alternative to typical modern husbandry systems, as long as adequate space is available.

The coexistence of four morphs of arctic charr in Thingvallavatn, Iceland, was demonstrated by investigations of morphology, habitat use, diet, endoparasitic fauna, life history, time and place of spawning, early ontogeny, and population genetics. Head morphology in embryos, juveniles and adults revealed the presence of two charr morphotypes, each including two morphs: (1) a benthic morphotype including large benthivorous (LB-) and small benthivorous (SB-) charr, featuring overshot mouth and relatively large pectoral fins, and (2) a pelagic morphotype including planktivorous (PL-) and piscivorous (PI-) charr, featuring termimal mouth and relatively small pectoral fins

1. Dung fly males guard their females from other males while the female oviposits. Occasionally an attacker grasps the female and a struggle for the possession of female begins. These contests obey ‘war of attrition’ rules. Outcomes and durations of struggles were analysed with respect to the various asymmetries present in the contests, using a technique that tests how the two opponents shift their fighting strategies in accordance with variations in a particular asymmetric feature. 2. In struggles, the attacking male is almost invariably larger than the guarding male (the ‘owner’). Males do not appear to play strategies that are fixed in relation to their own size, but play strategies that depend on their size relative to that of their opponent. No significant difference was found between struggle durations for two small opponents and those for two large opponents, though both were significantly different from large versus small opponents. As the relative size of the owner increases, the persistence of the attacker decreases significantly. That of the owner probably increases (though this is not proven). 3. The female's size relative to the owner's size also exerts a significant effect on the outcome. The larger the female, the greater the probability of takeover. This arises from a greater persistence of the attacker. The ‘resource holding power’ (RHP) of the owner is therefore considered to be influenced both by his size relative to that of the attacker and by his size relative to that of this female. In addition, the owner may have an inherent RHP advantage due to his initial grasp on the female. This may contribute to the fact that only 20–25% of struggles end in takeover despite the fact that the attacker is larger than the owner. 4. Another effect that must contribute to the low frequency of take-overs concerns the fact that the mean value of winning (the resource value) is higher for the owner than for the attacker. Resource value relates mainly to the number of eggs that remain to be laid at the time of the struggle. Though the owner may be unable to monitor this directly, there is a strongly significant negative correlation between owner's persistence and the time he had spent guarding. Thus he escalates as resource value increases. In contrast, attackers appeared to be unable to estimate resource value; their persistence was independent of the female's egg content. 5. The data strongly support the notion that dung flies assess RHP and resource value in contests and alter their fighting strategies accordingly. We discuss the data in relation to recent theoretical developments in the study of assessment strategy.

1. Laboratory experiments with yellow dung fly larvae, Scatophaga sfercoraria L. were carried out in the hope of clarifying the causal relationship underlying the extreme variation in body size in wild populations. 2. First, parents were collected in the field and newly hatched larvae exposed to different density levels under two temperature regimes (15°C and 20°C). Second, heritability experiments were done. 3. The results showed that density during the larval stage has a very significant effect on adult size. Male size is more affected than female size and the male larvae spend more time feeding than the female larvae with the result that the males are on average larger. Also, the additive genetic component is of little or no significance, supporting the notion that body size is positively related to fitness. 4. Finally, the results are discussed in relation to field data on the effects of size on both male and female reproductive success.