Very small, light dipole harmonic tags for tracking small animals

[Extract] Tracking animals provides a detailed picture of their behaviour and can be important in understanding their ecology. Tracking is especially useful for elucidating the ecology of animals that are cryptic during all or parts of their life cycle (Heyer et al. 1994; Langkilde and Alford 2002; Reynolds and Riley 2002). Amphibians, for example, can be hard to study outside breeding aggregations, and wildlife telemetry can provide insight on otherwise unknown aspects of their biology (Heyer et al. 1994; Naef-Daenzer 1993; Naef-Daenzer et al. 2005; Rowley and Alford 2007a, b, c; Rowley et al. 2007)