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Greylag geese (Anser anser) have been increasing in numbers in Europe during the last decades. They forage and roost in agricultural landscapes and may cause damage to sensitive crops. We studied field selection of greylag geese around lake Sörfjärden in south central Sweden where geese aggregate during the growing season. In this area a set-aside field was established in 2010, i.e., a field where geese can graze undisturbed, with the aim to reduce damage in surrounding conventional fields. The goal of our study was to investigate the general selection of the different field types as well as the specific set-aside field. We used a point survey count to estimate goose numbers and regression analyses to evaluate the relationship between presence or absence of greylag geese and field characteristics such as crop type, distance to roost site and field size. According to the top-ranked model, the probability of presence of foraging greylag geese was higher in spring and in grass fields, while the probability decreased with distance to roost site. Our results also show that the set-aside field in general was used more than other fields in the area during spring and summer but not during autumn. We conclude that it is important to consider variables affecting the probability of field selection by geese, such as season, crop type and distance to roosts to understand the behaviour of geese when establishing set-aside fields.

Ixodes ricinus ticks are Scandinavia's main vector for tick-borne encephalitis virus (TBEV), which infects many people annually. The aims of the present study were (i) to obtain information on the TBEV prevalence in host-seeking I. ricinus collected within the Øresund-Kattegat-Skagerrak (ØKS) region, which lies in southern Norway, southern Sweden and Denmark; (ii) to analyse whether there are potential spatial patterns in the TBEV prevalence; and (iii) to understand the relationship between TBEV prevalence and meteorological factors in southern Scandinavia. Tick nymphs were collected in 2016, in southern Scandinavia, and screened for TBEV, using pools of 10 nymphs, with RT real-time PCR, and positive samples were confirmed with pyrosequencing. Spatial autocorrelation and cluster analysis was performed with Global Moran's I and SatScan to test for spatial patterns and potential local clusters of the TBEV pool prevalence at each of the 50 sites. A climatic analysis was made to correlate parameters such as minimum, mean and maximum temperature, relative humidity and saturation deficit with TBEV pool prevalence. The climatic data were acquired from the nearest meteorological stations for 2015 and 2016. This study confirms the presence of TBEV in 12 out of 30 locations in Denmark, where six were from Jutland, three from Zealand and two from Bornholm and Falster counties. In total, five out of nine sites were positive from southern Sweden. TBEV prevalence of 0.7%, 0.5% and 0.5%, in nymphs, was found at three sites along the Oslofjord (two sites) and northern Skåne region (one site), indicating a potential concern for public health. We report an overall estimated TBEV prevalence of 0.1% in questing I. ricinus nymphs in southern Scandinavia with a region-specific prevalence of 0.1% in Denmark, 0.2% in southern Sweden and 0.1% in southeastern Norway. No evidence of a spatial pattern or local clusters was found in the study region. We found a strong correlation between TBEV prevalence in ticks and relative humidity in Sweden and Norway, which might suggest that humidity has a role in maintaining TBEV prevalence in ticks. TBEV is an emerging tick-borne pathogen in southern Scandinavia, and we recommend further studies to understand the TBEV transmission potential with changing climate in Scandinavia.

Ulver i Slettåsreviret har i flere år blitt beskrevet som nærgående av lokalbefolkningen og media. Fem individer av flokken ble derfor merket med GPS-halsbånd i januar 2017, samtidig som ni ulver fra naboflokken i Osdalsreviret også ble GPS-merket. Det Skandinaviske Ulveforskningsprosjektet SKANDULV har deretter, med noen dagers forsinkelse for ikke å forstyrre, fulgt opp ulvene i felt for å kartlegge deres atferd og forflytningsmønster. Vi har oppsøkt de fleste plassene hvor ulvene har stoppet opp. Slike plasser karakteriseres av klynger med GPS-posisjoner, såkalte clustere, og i kombinasjon med sporsnø er det ofte mulig å se ulvenes atferd i slike områder. For de to ulveflokkene ble det etter fortløpende GIS-analyser undersøkt til sammen 5827 ulveposisjoner (83% av alle heltimesposisjonene) i felt, hvorav 5729 (98%) av posisjonene var fordelt klumpvis på totalt 362 clustere. Undersøkte GPS-posisjoner representerte en periode på 160 og 301 døgn for medlemmer av henholdsvis Slettåsflokken og Osdalsflokken, og GPS-posisjonene ble undersøkt av 7 peroner til sammen 67 dager i felt i perioden 7. februar – 2. mars 2017. På henholdsvis 8 (5%) og 14 (7%) clustere i Slettås- og Osdalsreviret fant vi rester etter elg som etter all sannsynlighet var drept av ulv, og på et cluster i Slettås var det rester etter det som kan ha vært en liten hund. Clustere med elgkadaver i Slettåsreviret lå gjennomsnittlig 1434 m (SE = 825 m) fra nærmeste bebodde hus. Dessuten ble matrester, ofte fra åteplasser, funnet på 12 clustere i Slettåsreviret. Denne typen cluster lå gjennomsnittlig nærmere bebodde hus enn andre typer av clustere. Det nærmeste matrester-cluster var på en åteplass besøkt av ulv 46 m fra hus. En foreløpig analyse av Slettåsulvenes GPS-posisjoner viser at ulvene foretrakk å bruke områder mellom 500 – 2000 m fra bebodde hus. Sett i forhold til andel areal med forskjellige avstander til bebodde hus brukte ulvene de nærmeste 500m fra hus mindre enn forventet på dagtid og omtrent som forventet om natten. Av de totalt 3095 posisjonene med 1-timesintervaller i Slettåsreviret var 21 (0,7%) nærmere enn 50 m fra bebodde hus, samtlige tatt om natten. Den nærmeste heltimesposisjonen påvist på dagtid var 98 m fra et hus. Den korte studieperioden begrenser muligheten til å trekke allmenne konklusjoner om ulvenes atferd, men vi kan se fra forflytningsmønsteret og clusterfunnene at mat trolig er en avgjørende faktor for ulvenes arealbruk. Fordelingen av elg i vinterkonsentrasjonsområder nær hus, men også tilgang til menneskeskapte åteplasser og dyp snø i høyden synes på denne årstiden å forklare mye av ulvenes forflytningsmønster. For en helhetlig konklusjon, økt allmenn kunnskap og framtidig adaptiv forvaltning av ulv er et anbefalt minimum å sammenligne Slettås- og Osdalsulvenes arealbruk med tilgjengelig tidligere års materiale fra ulver som er GPS-merket og observert i mer enn 50 andre Skandinaviske ulverevir. English: Wolves in the Slettås wolf territory have for several years been described by local inhabitants and media as moving close to settlements. Five individuals of the pack have therefore been radiomarked with GPS-collars in January 2017, together with nine wolves of the neighbouring Osdalen pack. The Scandinavian Wolf Research Project SKANDULV followed up these wolves in the field to map their behavior, with a few days delay in order to leave them undisturbed. We visited most of the sites where the wolves had stopped their movements. Such sites are characterized by clusters of GPS-positions. Cluster visits in combination with the investigation of tracks in the snow allowed us to define the behaviour of the wolves on these sites. For the two wolf packs, we continuously visited 5827 GPS positions (83% of all recorded hourly GPS-positions). Of those, 5729 (98%) were distributed on a total of 362 clusters. The GPS-positions represented a period of 160 and 301 days of the Slettås- and Osdalen pack members, respectively. They were checked in the field by seven fieldworkers during a total of 67 working days during 7 February – 2 March 2017. On 8 (5%) and 14 (7%) clusters of Slettås and Osdalen pack respectively, we found remains of moose most probably killed by wolves. One cluster contained remains of probably a small dog. Clusters of the Slettås pack containing moose carcasses were on average 1434 m (SE = 825 m) off the closest inhabited house. We also found food remains, mostly from bait sites, on 12 clusters of the Slettås pack. These clusters were on average closer to houses than other types of clusters, with the closest being at a distance of 46 m to the nearest house. A preliminary resource selection analysis showed that the wolves of the Slettås pack preferred a zone of 500 – 2000 m off inhabited houses. They used areas within 500 m from houses less than expected during daytime and about as expected during night. Of the 3095 hourly positions of the Slettås pack, 21 positions (0.7%), all taken at night, were within 50 m from inhabited houses. The closest daytime positions was at a distance of 98 m from the closest house. The short study period is limiting general conclusions about wolf behaviour. Still, our preliminary analyses indicate that food is an important determinant of wolf habitat use. The distribution of moose in winter concentration areas close to settlements, the access to hunting bait stations, and deep snow at higher altitudes are probably important predictors of wolf movement patterns. For more integrated conclusions, increased knowledge and future adaptive management of wolves, we recommend to compare the habitat use of the Slettås- and Osdalen packs with the data of more than 50 Scandinavian wolf packs monitored with GPS by SKANDULV. Miljødirektoratet

Master i anvendt økologi. Evenstad 2016 Remote monitoring of wild animals by radio-tags and bio-sensors is frequently applied in wildlife research, monitoring and management. These methods require capture and often anaesthesia of animals that in turn may affect post-capture behaviour. Assessment of post-capture effects is needed to avoid biases in the research data due to capture-related effect on behaviour, but also to measure unnecessary discomfort and suffering for the animals. The Scandinavian wolf population has since its reappearance in the 1980´s been the subject to many studies, and the first wolves were radio collared in 1999. Between 1998 and 2015 several wolves have been captured in Scandinavia. For this study I used hourly GPS positions during the first 100 hours from 25 wolves chemically immobilized between 2001 and 2015. I examined how the cumulative post-capture movement was related to the intrinsic variables sex, body mass and social status, and to capture-related variables, number of captures, pursuit time and the type and dose of drugs used. Sex was the most important factor explaining patterns of post-capture movement. Males had a higher movement rate than females between the release and 23 hours post capture. Body mass was correlated with sex and was positively related to sex-specific movement rates. Contrary to my initial predictions, medetomidine given as an additional tranquilizer during handling increased the movement rate after capture. I also found weak relationships between movement rate and the time the wolf was chased by helicopter prior the immobilisation, and between movement rate and drug doses. The small sample size however limits the inferences that can be drawn from these models. I conclude that capture-related factors can induce differences in post-capture movements of wolves, and that sex is an important predictor of post-capture movement patterns.