Northern bald ibis 941


2004, there have also been exchanges with another seden- tary semi-captive colony in Tierpark Rosegg. The primary aim of the Konrad Lorenz Research Station project was to investigate social behaviour and its relationships with physiology, ecological aspects of natural foraging, and the establishment of traditions through social learning (e.g. Puehringer-Sturmayr et al., 2018). It also aimed to improve management and release methodology, to be applicable for wider northern bald ibis reintroduction. Since 2003 the Konrad Lorenz Research Station aviary


has been left open year-round. The population, which in 2018 comprised 13 adult pairs (Table 5), has remained sed- entary despite no longer being enclosed during the disper- sal period (Kotrschal, 2007). The birds use nearby foraging areas, spending the summer in the neighbouring valley, and returning to the aviary in autumn. The fledglings do not migrate, but up to 50% of them (in 2015–2017) undergo juvenile dispersal, flying north/north-east and coming back to Grünau at the end of the summer. From 2004 Tierpark Rosegg in Carinthia has also managed a small sedentary, seasonally free-flying northern bald ibis colony, which in 2018 comprised 18 adult pairs (Table 5). Numbers released and post-release survival during 1997–2014 are presented in Supplementary Tables 1 and 2.


Austria and Germany: reintroduction of a migratory subpopulation


In 2002 the project Waldrappteam initiated a 12-year feasi- bility study (2002–2013) to develop methods for the estab- lishment of migratory northern bald ibis colonies using human-led migration techniques, involving training birds to follow human foster parents in ultra-light aircraft (Fritz et al., 2016). During 2003–2018, a total of 318 chicks from European


zoos have been taken for hand rearing (Fritz et al., 2017). Before release, contact with the birds is limited to human foster parents to avoid habituation to other humans. Dur- ing the first weeks, hand rearing takes place at a zoo. Shortly before fledging, the birds are transferred to a field camp in the area where they will be released. Flight training takes 2 months, starting immediately after fledging, with gradually increased flights up to 100 km. The human-led migration starts mid August, when the young birds enter a state of migratory restlessness (Bairlein et al., 2015). The human-led migration routes cross the Alps to a wintering area in Southern Tuscany (Italy), with daily flight stages of up to 300 km and 8 hours (Fritz et al., 2017). In 2011, the first juveniles hatched in the wild and fol-


lowed conspecifics from Burghausen to the wintering site in Tuscany (Fritz et al., 2017). Since then, an increasing pro- portion migrates independently. Spring migration starts in late March, with the oldest birds departing first. Autumn


Oryx, 2021, 55(6), 934–946 © The Author(s), 2020. Published by Cambridge University Press on behalf of Fauna & Flora International doi:10.1017/S0030605320000198


TABLE 6 Breeding productivity of the northern bald ibis in the four breeding sites in Andalusia, Spain. Tajo de Barbate


Barca de Vejer


Year Pairs 2008 1


2009 1 2010 1 2011 2012 2013 2014 2015 2016 2017 2018


Fledglings 1


1 0


Fledglings/pair Pairs 1


1 0


4 7


15 22 14 19 22 14


1Nest boxes in open aviary.


5 2


17 21 17 26 25 29


1.3 0.3 1.1 1.0 1.2 1.4 1.1 2.1


4 1 0.3


2 1 1 1 9


4 1 0 2


12


2.0 1.0 0.0 2.0 1.3


Fledglings


Sierra del Retin1 Fledglings/pair Pairs Fledglings


Fledglings/pair Pairs


Torre de Castilnovo Fledglings


Fledglings/pair


Page 1  |  Page 2  |  Page 3  |  Page 4  |  Page 5  |  Page 6  |  Page 7  |  Page 8  |  Page 9  |  Page 10  |  Page 11  |  Page 12  |  Page 13  |  Page 14  |  Page 15  |  Page 16  |  Page 17  |  Page 18  |  Page 19  |  Page 20  |  Page 21  |  Page 22  |  Page 23  |  Page 24  |  Page 25  |  Page 26  |  Page 27  |  Page 28  |  Page 29  |  Page 30  |  Page 31  |  Page 32  |  Page 33  |  Page 34  |  Page 35  |  Page 36  |  Page 37  |  Page 38  |  Page 39  |  Page 40  |  Page 41  |  Page 42  |  Page 43  |  Page 44  |  Page 45  |  Page 46  |  Page 47  |  Page 48  |  Page 49  |  Page 50  |  Page 51  |  Page 52  |  Page 53  |  Page 54  |  Page 55  |  Page 56  |  Page 57  |  Page 58  |  Page 59  |  Page 60  |  Page 61  |  Page 62  |  Page 63  |  Page 64  |  Page 65  |  Page 66  |  Page 67  |  Page 68  |  Page 69  |  Page 70  |  Page 71  |  Page 72  |  Page 73  |  Page 74  |  Page 75  |  Page 76  |  Page 77  |  Page 78  |  Page 79  |  Page 80  |  Page 81  |  Page 82  |  Page 83  |  Page 84  |  Page 85  |  Page 86  |  Page 87  |  Page 88  |  Page 89  |  Page 90  |  Page 91  |  Page 92  |  Page 93  |  Page 94  |  Page 95  |  Page 96  |  Page 97  |  Page 98  |  Page 99  |  Page 100  |  Page 101  |  Page 102  |  Page 103  |  Page 104  |  Page 105  |  Page 106  |  Page 107  |  Page 108  |  Page 109  |  Page 110  |  Page 111  |  Page 112  |  Page 113  |  Page 114  |  Page 115  |  Page 116  |  Page 117  |  Page 118  |  Page 119  |  Page 120  |  Page 121  |  Page 122  |  Page 123  |  Page 124  |  Page 125  |  Page 126  |  Page 127  |  Page 128  |  Page 129  |  Page 130  |  Page 131  |  Page 132  |  Page 133  |  Page 134  |  Page 135  |  Page 136  |  Page 137  |  Page 138  |  Page 139  |  Page 140  |  Page 141  |  Page 142  |  Page 143  |  Page 144  |  Page 145  |  Page 146  |  Page 147  |  Page 148  |  Page 149  |  Page 150  |  Page 151  |  Page 152  |  Page 153  |  Page 154  |  Page 155  |  Page 156  |  Page 157  |  Page 158  |  Page 159  |  Page 160  |  Page 161  |  Page 162  |  Page 163  |  Page 164