Estimating the total number of wild animals in a particular location or country has always been challenging. Still, better data on wild animal numbers are needed to recognize changes, identify the causes, and what might be done to address such changes.
Rowan, Andrew N.
"Counting Birds and Other Wild Animals,"
WellBeing News: Vol. 3
, Article 3.
Available at: https://www.wellbeingintlstudiesrepository.org/wbn/vol3/iss8/3