1. INTRODUCTION 21.1. Background analysis 21.2. Migratory Birds and HPAI 51.3. Using SIA to understand the dissemination of HPAI - The way ahead! 72. ANIMAL MIGRATION TRACKING METHODS 102.1. Extrinsic Markers 102.2. Intrinsic markers 152.2.1. The Nitrogen Cycle 212.2.2. The Sulphur Cycle 222.2.3. The Oxygen Cycle 222.2.4. The Hydrogen Cycle 232.3. The Stable Isotopes of Water on a Spatial Scale 242.4. Deriving isoscapes in the absence of GNIP data 272.5. Use of Stable Isotopes for Migration Studies 282.6. Approaches for Determining Migratory Connectivity 322.6.1. Classification Trees to Predict Origins 382.6.2. Likelihood-Based Methods to Predict Origins 382.6.3. Migration Studies using Stable Isotopes. 392.6.4. Determining migratory connectivity for waterfowl in Asia 413. PRACTICAL CONSIDERATIONS 463.1. Sample Collection and Tissue Preparation 463.1.1. Questions of Sample Heterogeneity 483.1.2. Preparation of feather samples 483.2. Other Stable Isotopes for Migration Research 523.2.1. Sampling Instructions for Water δ18O and δ2H - Rivers / Lakes / Groundwater 523.2.2. Sampling Instructions for Bird Feathers for use in SIA 533.2.3. Sampling wild birds in the field 553.2.4. Sampling Strategy for H5N1 564. REFERENCES 60