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Prey switching is an important part of predator feeding and breeding ecology since prey populations and therefore prey availability is dynamic. Deliveries of prey made by the Eurasian kestrel (Falco tinnunculus) breeding in a nest box in southern Norway, were recorded with a camera. Temporal activity of ground dwelling prey was recorded using five Reconyx cameras mounted in tunnel shaped boxes. Both were analysed in terms of temporal overlap. Total observations made of nest deliveries and camera traps, respectively were: 383 and 80 of Shrews (Sorex spp.), 190 and 6 of lemmings (Lemmus lemmus), 102 and 53 of the bank vole (Myodes glareolus), 60 and 64 Microtus voles (Microtus spp.) and 20 deliveries of birds to the nest. Shrews, Microtus voles and the bank vole were defined as the main prey and birds as an alternative prey. The main prey species had similar, but varying temporal patterns of activity and deliveries. The kestrel increased deliveries of birds (their alternative prey) when deliveries of main prey were decreasing in the hours between 11:00 and 18:00, the decrease in main prey deliveries around this time was small, and bird deliveries in these hours were probably an additive energy source. The kestrels deliveries of alternative prey did therefore follow a consistent hourly trend. Our results are similar with other findings made of Norwegian breeding kestrels by Steen et al., (2011a), where the same patterns of alternative prey deliveries occurred, around the same timeframe as our results, but with another alternative prey, the viviparous lizards (Zootoca vivipara). This consistent temporal change in prey composition, where alternative prey was commonly delivered for a brief period, should increase the prey mass delivered to the nestlings, and create a more stable feeding pattern throughout the day. The switch to an increase of bird being delivered at the nest were a discreet, but rapid form of prey switching. This thesis is to my knowledge the only study using this methodology to determine hourly changes in prey composition for a predator. M-NF

I studied home range and area use of the female Eurasian kestrel (Falco tinnunculus), in the boreal forested area of Trysil municipality (61°00' - 61°41'N, 11°44' - 12°52'E) in the breeding season of 2011, a peak vole year. Six females were tagged and radio-tracked using VHF telemetry in the pre-fledging period, and two of these females were additionally followed in the early post-fledge period. Females were located between 49 and 141 times in the pre-fledging period ( χ = 98 ± 13 SE), totaling 589 observations, which allowed the investigation of area use questions using the Minimum Convex Polygon (MCP) and fixed kernel href methods. I found a large variation in home range size between females as measured by the overall 100% MCP (range 0.69 - 6.16 km2, median = 0.94 km2, χ = 1.84 ± 0.87 SE km2), and in the levels to which each home range was centered on the nest. Home range size was significantly positively correlated with the proportion of bog with forest (overall 95% kernel) and the proportion of forest of developmental stage 3 present (overall 95% kernel, and overall 100% MCP), and significantly negatively correlated with proportion of pooled developmental stage 4 and 5 (overall 95% kernel). A trend approaching significance was found for negative correlation with Microtus vole abundance (overall 95% kernel). A higher probability of being in the core foraging area (foraging 50% kernel) was associated with decreased distance to nest and decreased distance to bog, highlighting the importance of maintaining proximity to the nest site for the kestrel as a central-place forager, and the importance of proximity to open habitat. In addition, post-fledge tracking highlighted the importance of the nest in the early fledging period. My results indicate the importance of taking into account vegetation structure and how it relates to prey availability, when looking at the effect on home range size. I further suggest that the role of modern forestry practices should be investigated, with regards to the effects habitat fragmentation and patch size and shape may play on spatial and temporal area use by the female kestrel in boreal forest. 2018-08-15 M-NF