The Earth is home to about 50 billion wild birds, which is six times more than human beings on the planet. A new study by scientists at the University of New South Wales says that there are about six birds for every human on this earth.
The new study also warns that most species are very rare and only a handful number in the billions. They mention that only four undomesticated species are in the club of billion plus individuals.
NUMBERS IN BILLIONS
As per the estimates, the top ten birds in numbers are House Sparrow (1.6 billion), European Starling (1.3 billion), Ring-billed Gull (1.2 billion), Barn Swallow (1.1 billion), Glaucous Gull (949 million), Alder Flycatcher (896 million), Black-legged Kittiwake (815 million), Horned Lark (771 million), Sooty Tern (711 million), and Savannah Sparrow (599 million). However, the study points out that the umber of 1180 species are fewer than 5000 birds each.
ALGORITHM
The researchers collected the records with scientific observations to develop an algorithm to estimate the population for almost all the species. They came across a large number of rare bird species than a few common bird species.
Corey Callaghan (University of New South Wales, Australia), who led the research said that it was good to see a large number s rare bird species.
CITIZEN SCIENCE DATA
Callaghan and his colleagues took citizen science data on bird sightings from the online database eBird to build a model for calculating the numbers of species. They als cross checked with other data on well studied birds. The model was then extrapolated out to 9700 species, arriving at a median of 50 billion wild birds globally.
Corey Callaghan said that he hoped that the models over time could help in charting out the species that are in decline and where conservation efforts are needed. The calculation of 50 billion individual birds represented the median estimate the model produced for the total number of birds worldwide, he said.
A FEW WELL STUDIED SPECIES
He also mentioned that only a few bird species are well studied. However, the collection of citizen scientists travelling all over the world helps in counting every bird that they see. He also mentioned that they tried to fill the gap in the data that were otherwise not filled by other data.
Despite a comprehensive data, Cornwell pointed out some uncertainties in the figures. They have decided to refine the model as more professional research on more species occurred.
