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

Nest locations were regularly distributed at a minimum distance of 1.6km between
active nests; however as the spatial scale increased (i.e. as distance between the
nests increased), the degree of regularity decreased.
2.5.6 Display flights
High-circling displays by single birds or a pair can be seen throughout the year but
are more intense over the nest area in March and early April by both male and
female.
Several types of display flight have been described for the goshawk, as follows:
sky-diving or sky-dance display involving high circling, flapping and soaring in
tight spirals; undulating and slow flapping flight (gradually losing height);
sometimes further circling to regain height; and plunging from a height of up
to several hundred metres into the nesting wood with wings held towards the
side (Hardey et al., 2006);
a display involving an undulating flight, like a woodpigeon but with even
sharper descents and ascents ‘as if rebounding from an invisible elastic
surface’ with wings almost closed (Joubert & Margerit, 1986 in Kenward,
2006);
zigzag chasing flights between the trees (Schnure, 1963 in Kenward, 2006).
These flights may represent misplaced aggression as opposed to normal
display, although they have been reported as being more prevalent than
display flights above the canopy; and
female goshawk displays occurring above the woodland canopy on sunny,
relatively windless days. During these, the female holds the long, main tail
feathers together and the snow-white undertail coverts spread apart so wide
that the goshawk appears to have a short, broad tail. The display involves
slow deliberate wing-beats, with the wings held stiff and straight (Demandt,
1927, 1933 in Kenward, 2006).
Both topographic and thermal soaring are used by goshawk, the former along ridges
or where updrafts occur at the windward edges of dense woodland (Kenward, 2006).
82% of 71 observed soaring flights were in the middle of the day, from late morning
to early afternoon. Soaring occurs in the warmest parts of the day, when thermals
are present, and also tends to occur in the warmest parts of the year. Goshawks
sometimes soar high, up to 300-400m, to be easily noticed (Kenward, 2006). The
travelling speed of a goshawk is estimated to be 15ms -1 (Rutz, 2006).
2.5.7 Competitive behaviour
Edge of territory interactions with conspecifics
Goshawk home ranges, during both the breeding season and winter, overlap
considerably (Hardey et al., 2006; Kenward, 2006), but the immediate nest site is
defended (Hardey et al., 2006). Although juvenile goshawks share foraging areas
extensively, core areas of territorial adults do seem to be more discrete (Kenward,
2006), indicating a greater degree of separation during the breeding season. Male
goshawks do not move far to breed, the majority probably having home-ranges
created between other breeding pairs rather than becoming ‘floaters’ in the
population.
Goshawk nests tend to be regularly spaced (Rutz & Bijlsma, 2006), as they are for
many raptors (Newton, 1979). Territory spacing is most regular at a small scale,
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