Ever since human interest in birds went beyond fried chicken legs and hard-boiled eggs, studying our feathered friends has become serious business. Especially the question ‘how much?’ has been entertaining bird watchers for over a century. It started in 1899 with counting feathers. American Richard McGregor was the first. He plucked a pregnant gull and a gull and shared his count with his colleagues: 1,899 feathers in the pregnant and 6,544 in the gull. Counting feathers isn’t particularly exciting, because it wasn’t until 1933 that wild ducks were plucked with the utmost care: 11,903 feathers. It was completed in 1937. The record then set – 25,216 feathers in one swan whistle, of which 20,177 in the head and neck – has never been surpassed.

Molecular bristles

Then ornithologists try to determine how many different species of birds there are around the world. This tally – literally by searching museum collections, bird books and in scientific bird magazines – took place from 1931 to 1987. This gave a total of 9,159 species. There is still discussion about that number, which arises from key questions about what species a bird really is and how you determine it – by eye and yardstick or in a DNA lab. In 2016, four Americans threw bats into the cage. By combining ancient measurements, modern molecular retrieval and clever calculations, they doubled the number counted by hand from 9,159 to 18,043 different bird species.

50 billion

Finally, the question of how many individual birds there are. So all the wild birds, everywhere, added up. Counting all the birds individually was of course completely impossible, but at the end of the last century the counter remained ‘between 200 and 400 billion’. That estimate, as it remains, is (strongly proven) lowered to 50 billion by 2021, with the top three being 1.6 billion house sparrows, 1.3 billion starlings and 1.2 billion ring-billed gulls. Fifty billion birds. What is special about this study is that the tally results are also based on accessible bird counting events such as the Christmas Bird Count in North America, the Greater Parks Bird Watch in the United Kingdom and – yes – our very own National Parks Bird Count which is due to be held this weekend.

Number of garden birds

It was the ancestor of Jac’s natural studies. P. Thijsse who wrote in 1932 in the famous magazine ‘De Levende Natuur’: “Every year around Christmas a group of Americans go out for one day to count birds, both species and individuals. People also try it in our country but do not continue, which really regrettable.” If only he had known. The National Park Bird Counting started in 2003 and got more and more people enthusiastic about birds. By 2022, the 170,000 participants totaled more than 2.4 million, including 450,000 house sparrows, 300,000 great tits and 200,000 blackbirds.

Come on listeners, walk to the window and count the birds for half an hour. Still can as long as it’s light. View, count and enter species and numbers count.nl bird park. Fifty billion!