Skip to main content
Fig. 6 | Animal Biotelemetry

Fig. 6

From: How to improve the accuracy of height data from bird tracking devices? An assessment of high-frequency GPS tracking and barometric altimetry in field conditions

Fig. 6

Typical examples of height profiles of high-frequency tracks: a example showing realistic height profile in high-frequency sampling (thermal ascent flight from ground level to c. 110 m a.g.l., descending gliding flight back to approximate ground level; marsh harrier, tag model UvA-BiTS 6C.L); b 3D representation of the same track showing zig-zag pattern during thermal ascent (1) and straight descending gliding flight (2); yellow points: wind turbines; satellite image: Google Earth; c example showing closeness between GPS and barometric height, accuracy time lag in GPS height data in the first minute of the sequence (quickly decreasing GPS height) and drift of GPS height in stationary periods (marsh harrier, Ornitela OT-15); d example showing “spikes” in GPS height data from Milsar tags (hen harrier, Milsar GsmTag-U9). Note different time scales on the x-axis between panels (a, b 10 min, c 90 min, d 60 min). a.g.l. above ground level, stat. stationary

Back to article page

Animal Biotelemetry

ISSN: 2050-3385