Motion detection or time lapse? A comparison of camera trap triggers in
the monitoring of elusive ground dwelling birds
Abstract
Wildlife cameras have emerged over the recent years as an effective
research tool for collecting various types of data on wild animals, and
they are used increasingly also in avian studies. However, choosing the
best method to collect data depends on the aim of the research and the
characteristics of the target species and its habitat. Here, we compared
the performance of game cameras taking images by passive infrared motion
sensitive (PIR) and time-lapse triggering in gathering occurrence and
relative abundance data of the taiga bean goose (Anser fabalis fabalis)
in peatlands across Finland in 2020-2021. We found the time lapse
trigger mode to be more efficient in collecting data on goose presence
than PIR triggering. However, there was no significant difference in the
goose numbers between the two trigger modes. We also found the capture
probability and relative abundance to vary between years, but this could
be attributed to random inter-annual variation. In general, we find time
lapse to be a more suitable method to study elusive ground dwelling
birds like the taiga bean goose due to fewer required visits to camera
sites compared to motion triggered cameras that may produce a lot of
empty images due to false triggering. This reduces the disturbance to
the geese and other wildlife during the sensitive breeding period.