Digital aerial surveys – HiDef

Since 2014, we use the high-resolution digital video system developed by our British partner company HiDef Aerial Surveying Ltd. to carry out seabird and marine mammal surveys. By now, we at BioConsult SH can look back on more than 800 flights in nine European countries.

Disturbance-free surveys using high-resolution cameras

The HiDef-system consists of four high-resolution video cameras, recording the sea surface at a resolution of 2 cm/pixel across a transect of 544 m width from an altitude of over 500 m. The cameras are slightly tilted forwards or backwards and mounted in a rotating rig to keep them turned away from the sun avoiding reflections and data loss. The flight altitude ensures save surveys in areas with wind farms where observer flights at altitudes of 76 m or 183 m will not be possible and effectively avoids disturbance of resting birds. 

The very high resolution of the images and a frame rate of approximately eight images per second allow our experienced image analysts and ornithologists to reliably detect all birds and marine mammals and to even distinguish between similar species. In the quality assurance process, 20 % of the video footage is subject to an independent review to meet the highest standards of data quality. Permanent storage of the images allows clients and authorities to re-review all data at all times and thus ensures a legally secure basis for our expert reports.

Reference projects

Papers and reports

Žydelis, R., Dorsch, M., Heinänen, S., Nehls, G., & Weiss, F. (2019)

Comparison of digital video surveys with visual aerial surveys for bird monitoring at sea

J Ornithol (2019)