Colombia is without doubt the country with the most bird species. The exact number of bird species in Columbia however depends on who is counting!
How we found the country with the most bird species
Accoring to Birdlife International, columbia is home to 1,878 species of bird. Avibase on the other hand counts species based on many different taxonomies and put the number at 1,958 Clements 2018 taxonomy, 1,908 based on IOC 9.2 taxonomy and 2,016 based on HBW and Birdlife 2018 taxonomy. Finally, volume 25 of Fundación ProAves’ scientific journal Conservación Colombiana put the total at 1,934 for 2018.
So why the large range from a minimum of 1,878 to a maximum of 2,016? The difference is due to two main factors. The first is due to the difference is taxonomic authorities and how they define and consider each species. The second is due to differences in how the different organisations decide what the requirements are for a new species to be added to the list.