Literature review to assess bird species connectivity to Special ...

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whereas over large areas the nests tend to be clumped, presumably in the best habitat (Reich et al., 2004). Regular spacing indicates that social behaviour, in the form of territoriality, limits the number of goshawks that breed in an area, with nonbreeders constrained to areas less suitable for breeding. 2.5.8 Habitat use Likely habitat use Habitat type and structure is important to goshawks. It supports prey populations, provides structure and concealment when foraging (e.g. for perches) and nesting, and provides cover from predators (Kenward, 2006). Goshawk were historically confined to mature forests, but now also nest in smaller woods, younger stands (Forsman, 1999), and urban areas (Rutz, 2006). Goshawks are usually found close to woodlands (Kenward, 2006; Hardey et al., 2006) but also hunt in open areas, especially outside of the breeding season. Goshawk are pause-travel hunters, using a technique of short-stay perched hunting (SSPH) as an alternative to soaring and low prospecting flights (Kenward, 2006). SSPH dominates hunting behaviour in winter and continuous forest, but soaring becomes more frequent in warm weather and can dominate hunting of urban goshawks during breeding (Rutz, 2006). Goshawks favour woodland edge zones. Perch locations of radio-tagged goshawks in Sweden indicated 73-76% of perch locations were within 200m of a woodland edge. Radio-tracking studies in Britain and Sweden have shown most kills are made in close proximity to edge habitat (within 100m, one flight distance) when foraging for lagomorphs, pigeons and pheasants in fragmented woodland (Kenward, 2006). Goshawks have also been recorded favouring large blocks of mature forest for mammal prey, such as squirrels, in the Scottish Borders (Petty et al., 2003) and Swedish taiga (Kenward, 2006). Nesting ranges, which are generally less than 5ha in extent (Petty, 1996), are normally found in large blocks of mature forest. They can occur in woods smaller than 3ha (Marquiss & Newton, 1982) but usually only where there is a lack of extensive woodland elsewhere. 2.5.9 Winter behaviour Winter dispersal Juveniles disperse from their natal areas in late summer (June to August). The only data on natal dispersal distances come from the Scottish Borders, where males moved significantly shorter distances (median: 14.7km) than females (median: 31.7km) (Petty & Anderson, 1996). The pattern of breeding range increase is therefore one of creeping expansion (Lensink, 1997). The greatest natal dispersal distance recorded, 70km was by a female reared in the Peebles area that settled to breed in Kielder Forest, Northumberland. Table 2 sets out winter foraging ranges for goshawk. These are believed to extend up to 2000-4000ha (equivalent to foraging distances of 2.5km to 3.6km) for Western Europe between 55-58° latitude, including Scotland (Kenward, 2006). Studies of winter foraging distances from roost sites are limited within the scientific literature. At higher elevations in the Borders, adult males appear to be the only sex/age class that over-winter, suggesting that some females move away from their home ranges after breeding (Petty, 2007b). 14
Ringing recoveries of an adult female provided insight into the range of movements by some goshawks. Ringed as a nestling near Eskdalemuir, the bird bred for a number of years in Galloway (both Dumfries & Galloway) 46km from its natal area, and was finally recovered dead during the winter in Keswick, Cumbria (Petty, 2007b). Table 2 – Goshawk winter territory estimates Location Year Area per territory (ha) Reference Rural Oxfordshire, UK 1973 - 1975 380-1360ha; equivalent to a foraging distance of 1.1-2.1km. Kenward (1982) Pheasant release area: 2000ha; equivalent to a foraging distance of 1.1-2.1km. Central Sweden 1976 - 1978 Mainly wild pheasant area: 2600ha; equivalent to a foraging distance of 2.9km. Kenward (1982) Only wild pheasants: 5400ha; equivalent to a foraging distance of 4.1km. 15
Page 1 and 2: Scottish Natural Heritage Commissio
Page 3 and 4: COMMISSIONED REPORT Summary Literat
Page 5 and 6: Tables Page Table 1 - Species revie
Page 7 and 8: 1. INTRODUCTION Proposals for opera
Page 9 and 10: 2. SPECIES ACCOUNTS 2.1 Red-throate
Page 11 and 12: 2.2 Black-throated diver 2.2.1 Fora
Page 13 and 14: High flying, up to 1000m, can also
Page 15 and 16: moved in successive years between s
Page 17 and 18: 2.5 Goshawk 2.5.1 Foraging Core for
Page 19: Nest locations were regularly distr
Page 23 and 24: 1986). A pair on a home range in th
Page 25 and 26: Grant & McGrady (1999) followed two
Page 27 and 28: 2.7.5 Habitat use Likely habitat us
Page 33 and 34: will subsequently role away, or til
Page 35 and 36: 2.11 Short-eared Owl 2.11.1 Foragin
Page 37 and 38: 2.12 Black grouse 2.12.1 Foraging H
Page 39 and 40: making longer movements (5 to 10km)
Page 41 and 42: Thompson, 1998). Other interactions
Page 43 and 44: 2.14 Greenshank 2.14.1 Foraging Cor
Page 45 and 46: 2.15 Dunlin 2.15.1 Foraging Foragin
Page 47 and 48: 2.16 Curlew 2.16.1 Foraging Core fo
Page 49 and 50: 2.18 Wintering geese 2.18.1 Foragin
Page 51 and 52: to about 7 km from the roost (Malco
Page 53 and 54: 3.2 Foraging ranges during winter s
Page 55 and 56: 4. REFERENCES Arroyo, B.E. Leckie,
Page 57 and 58: Fuller, R.J. & Lloyd, D. (1981). Th
Page 59 and 60: Mearns, R. (1985). The hunting rang
Page 61 and 62: Rebecca, G.W. & Bainbridge, I.P. (1
Page 63 and 64: Whittingham, M.J., Percival, S.M. &

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