Habitat use and population dynamics of the Azure-Winged Magpie ...

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colony as breeding activities in 2007-2009 were all in the Main Breeding Area (Gantulga, 2010). It is not known whether this is just a chance and single event for 2010, or marks the adoption of a separate breeding site for this colony following the 2009 fire. Colonisation of the Khonin Nuga valley by C. cyanus may be a very recent event. C. cyanus were not reported to be present (at least in big family units) and breeding in the Khonin Nuga Valley until 2005. There are speculations about the coincidence between the appearance of the birds and the outbreak of Gypsy Moths (M Mühlenberg, pers. comm.). A large outbreak of Gypsy Moths (Lymantria dispar) occurred during 2001-2006, and again in 2008 around the Khonin Nuga Research Station (Gantigmaa, 2004; M. Muehlenberg, pers. comm.; Altantsetseg, unpublished data). Both adult and larvae are an important food source for C. cyanus adults and chicks (Gantulga, 2010; pers. obs.). This is the only colony known to inhabit the valley near the field station. Searches have been made by colleagues and I around the valley (following the Eroo river basin and its branch river basins) and, based on conversations I had with the local ranger and other scientists who have been working since 2002 in this field station, no other colony is known to inhabit the immediate region of Khonin Nuga (ca. 20km upstream and 10km downstream from the research station). In August 2003, 100-120 C. cyanus individuals were seen c.a. 2 km away in Sharlan Valley, south- east of the Khonin Nuga valley. A number of birds (ca. 6-10) made frequent visits to the Khonin Nuga valley in 2004, but did not remain in the valley (M. Mühlenberg, pers. comm.). 4.1.1 Foraging and other behaviours of the Khonin Nuga Cyanopica cyanus At Khonin Nuga, C. cyanus were observed taking a variety of food items including insects, berries and carrion; a similar variable diet was also found in the Japanese and Iberian populations (Hosono, 1966; Madge & Burn, 1994; Snow et al., 1998; Canário et al., 2002). Individuals from Khonin Nuga utilised different strata (from ground level to ca. five metres in height), foraged in at least 12 plant species and performed a range of food/ prey obtaining behaviours but rarely actively pursued prey. From my observations, C. cyanus always moved and foraged with conspecifics, never with other species. There were occasions in both 2009 and 2010 that a flock of Eurasian Jays, Garrulus glandarius (20-30 individuals) followed the C. cyanus whenever they were foraging, and mimicked the latter’s vocalisation. C. cyanus’s behaviour was neutral when woodpeckers 60
(Dendrocopus spp. and Picus canus) were present and/ or feeding in the same area. C. cyanus may exert some aggressive dominant behaviour (e.g. chasing off other species) towards other smaller species such as wagtails (Motacilla spp.) if both are competing for food. Hosono (1975) found similar behaviour in his study in Nagano, Japan. No obvious territorial behaviours towards conspecifics and other species were observed in this colony of C. cyanus, even during the breeding season. I also did not observe any sort of obvious aggression amongst group members. Reports from observations in Iberia and Japan show a mix of results, with some populations showing territorial behaviours, such as chasing (Komeda et al., 1987; Snow et al., 1998; S Imanishi, pers. comm.), but others not (Valencia et al., 2000). This non-territorial behaviour may stem from relatedness of group members, but kinship has not yet been studied in these populations. Behavioural observations were limited by the difficulty of observing C. cyanus when they foraged in dense bushes (e.g. Padus asiatica and Salix spp.). There is no other way around this problem, or to improve it without alarming the whole colony, apart from conducting many, or chance observations regarding the activities of C. cyanus in dense scrub. Observation events of areas on the true right of Eroo River (i.e. the Main Breeding Area and Sharlan Meadows) were limited when the water level was high, as it was impossible to cross by foot or horse. Therefore, when this happened (about two to three days in 2009 and one week in 2010), observations were limited to the true left of the Eroo, on the true right river bank and ca. 20 metres inland from the true right of the river. 4.2 Radio-tracking VHF radio tracking was employed in this study because it is by far the cheapest tracking method and had reasonable accuracy. As far as I can determine, no VHF radio tracking research has been published for this species before. Overall, the radio-tracking attempts were not successful on C. cyanus, as I had difficulties getting accurate signal positioning from transmitters and securing transmitters onto the tail-feathers of C. cyanus. Using VHF radio tracking is not without its problems. Tests of radiotelemetry accuracy have shown signal reception and location accuracy to be affected by several factors, amongst them reflected signals (“signal bounce”) and attenuation resulting from vegetation cover (Withey et al., 2001), which I think were the main reasons for difficulties in getting signals from the radio- 61
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Copyright Statement Lincoln Univers
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The Azure-winged Magpie Cyanopica c
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proportions of banded adults and ju
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Table of Contents Abstract ........
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List of Tables Table 2.1 Definition
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Figure 3.9 Proportion of time spent
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1.1 Impact and effects of fire Chap
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In contrast to the arguments above,
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capacity will result in increased i
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The subject of this study, Cyanopic
Page 21 and 22: Chapter 2 Methods 2.1 General Infor
Page 23 and 24: The extreme disjunct distribution o
Page 25 and 26: The IUCN lists Cyanopica cyanus as
Page 27 and 28: Clutches range from four to eleven
Page 29 and 30: logging set up a makeshift camp ca.
Page 31 and 32: 2.2.2 Cyanopica cyanus in Khonin Nu
Page 33 and 34: 2.3 Methods 2.3.1 Data collection H
Page 35 and 36: If the group moved on to another ar
Page 37 and 38: Population Dynamics Nest predation
Page 39 and 40: I investigated the similarities of
Page 41 and 42: I performed a Chi-Square Test of As
Page 43 and 44: Figure 3.2 Home range of Cyanopica
Page 45 and 46: Kassel The area used by the birds i
Page 47 and 48: 2007. It is also the primary night
Page 49 and 50: (a) (b) Figure 3.6 Detailed map of
Page 51 and 52: significantly from 9% in 2009 to 15
Page 53 and 54: observed individuals in Betula plat
Page 55 and 56: 3.3 Population Dynamics 3.3.1 Frequ
Page 57 and 58: Table 3.6 Life history of individua
Page 59 and 60: Number of individuals 60 50 40 30 2
Page 61 and 62: Proportion (%) of individuals re-si
Page 63 and 64: 3.3.4 Breeding individuals Out of t
Page 65 and 66: 3.3.5 Pair-bond retentions Due to t
Page 67 and 68: Table 3.12 Banded females and known
Page 69 and 70: Proportion (%) of individuals 80 70
Page 71: coordinate system. However, the res
Page 75 and 76: also be useful for further studies
Page 77 and 78: Cyanopica cyanus respond to aerial
Page 79 and 80: e explained by the formula which us
Page 81 and 82: Breeding individuals, pair-bonds, s
Page 83 and 84: UNICEF, 2010). This event and the f
Page 85 and 86: (Bayartaa et al., 2007). In Norther
Page 87 and 88: This study provides a baseline for
Page 89 and 90: BirdLife International. (2009). Cya
Page 91 and 92: Ford, H.A. (1989) Ecology of Birds:
Page 93 and 94: Kirkpatrick, C. & Conway, C. (2010)
Page 95 and 96: Pryde, M.A. (2003) Using Program 'M
Page 97 and 98: Valendik, E.N., Ivanova, G.A., Chul
Page 99 and 100: Appendix A Datasheet for observatio
Page 101 and 102: Gypsy Moth, Lymantria dispar larvae
Page 103 and 104: The author coming back from a day i
Page 105: Dense Padus asiatica form a ‘cano
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