The Shelduck: A Study in Behavioural Ecology

Cover......Page 1
Frontmatter......Page 2
Contents......Page 6
Acknowledgments......Page 10
1 - Introduction......Page 12
2.1 Taxonomy......Page 16
2.2 Description......Page 17
2.3 Shelduck weight......Page 20
2.4 Diet......Page 25
2.5 Feeding behaviour......Page 26
2.6 World distribution......Page 28
2.7 The shelduck in Britain......Page 32
2.8 The moult migration......Page 35
2.9 The annual cycle......Page 48
3.1 Arrival......Page 51
3.2 Dispersion......Page 55
3.3 Feeding......Page 57
3.4 Agonistic behaviour......Page 58
3.5 Frequency of aggressive interaction......Page 65
3.6 Dominance......Page 67
4 - Territories......Page 89
4.2 The ages of territorial shelducks......Page 90
4.4 Establishment of territories......Page 92
4.5 Dispersion......Page 94
4.6 Territory or range size......Page 99
4.7 Use of the territory for feeding......Page 106
4.8 Benefits and costs of being territorial......Page 111
4.9 Consequences of territoriality for the population......Page 114
4.10 Abandoning the territory......Page 117
5.1 Timing of prospecting......Page 118
5.2 Grouping......Page 123
5.3 Sub-groups: `parliaments' and `communes'......Page 126
5.4 Behaviour in the nesting area......Page 130
5.5 Interference between prospecting pairs......Page 135
5.6 Costs and benefits of grouping while prospecting......Page 140
5.7 Nest sites......Page 146
6.1 The timing of laying......Page 150
6.2 Behaviour during laying......Page 152
6.3 Clutch size......Page 153
6.4 Behaviour during incubation......Page 156
6.5 Hatching......Page 160
6.6 Nesting success......Page 161
6.7 Individual strategies in nesting......Page 167
6.8 The proportion of the population which breeds......Page 168
7.1 Leaving the nest......Page 172
7.2 Feeding......Page 176
7.3 Parental behaviour......Page 177
7.4 Brood ranges......Page 181
7.5 Aggressive interactions between brood pairs......Page 183
7.6 Brood-mixing and creches......Page 190
8.1 Survival rates......Page 197
8.2 Predation......Page 199
8.3 Duckling survival in relation to density......Page 200
8.4 Duckling survival in relation to aggressive interaction......Page 203
8.5 Duckling survival and weather......Page 206
8.6 The relative importance of different mortality factors......Page 213
8.7 Strategies for rearing ducklings: single or mixed broods?......Page 215
8.8 Development, fledging and dispersal......Page 223
9 - Recruitment and the non-territorial flock......Page 229
9.1 Return of the young......Page 230
9.2 Flock dispersion......Page 231
9.3 Sex and age composition of the flock......Page 232
9.4 Immigration into the flock......Page 237
9.6 Limitation of recruitment into the flock......Page 239
9.7 Recruitment from the flock to territories......Page 243
9.8 Recruitment strategies for young shelduck......Page 245
10 - The limitation of shelduck populations......Page 248
10.1 Changes in local population size......Page 249
10.2 Shelduck mortality......Page 252
10.4 Breeding......Page 261
10.5 Are estuarine shelduck populations self-maintaining?......Page 263
10.6 Limitation of population size......Page 265
References......Page 267
Subject index......Page 280
Author index......Page 285