Data from: Multi-image flock size estimation with CountEm: A case study with half a million Common Eiders and Greater Snow Geese.

The present data set is related to the manuscript "Multi-image flock size estimation with CountEm: A case study with half a million Common Eiders and Greater Snow Geese" submitted to the Ecosphere journal. The files COEI_data.csv and GSGO_data.csv contain data and results of the 179 COEI and 99 GSGO ECA Flocks images respectively. The files have one row per image. Both files have 9 columns corresponding to the following variables: “Filenumber” is used to identify the number of the corresponding image, namely “001” to “099” for GSGO, and “001” to “179” for COEI. “N”: Total number of annotated birds in the image. “Nest”: Bird number estimation (bN 439 ) obtained with a single real mode CountEm run. “CE_sim”: Empirical coefficient of error (relative standard error, CEe(bN 440 )) obtained from 2000 simulated measurements in simulation mode. “f”: Sampling fraction used in the real mode CountEm run. “n0”: Initial number of quadrats used in the real mode CountEm run. “Q”: Total number of birds (i.e. sample size) counted in the real mode CountEm estimation. “n”: Number of non-empty quadrats counted in the real mode CountEm estimation. “UserTime”: Counting time (in minutes) in the real mode CountEm estimation. “ManualTime”: Counting time (in minutes) of the manual annotation process with ImageJ.