Migratory birds being wiped out by human landscape modifications

By Mark Waghorn via SWNS

Migratory birds are being wiped out by human modification of the landscape over recent decades, according to new research.

They are suffering huge declines through the building of infrastructure - from roads to wind turbines.

Our feathered friends are also killed by hunters and manmade climate change, say scientists.

The University of East Anglia team found populations have been greatest hit among species that visit areas with more buildings, power lines - and people.

Co author Dr. Claire Buchan, from the School of Biological Sciences, said: "We found human modification of the landscape in the birds' distribution ranges in Europe, Africa and Western Asia is associated with declining numbers of over 100 Afro-Eurasian migratory birds.

"When we talk about modification of the landscape, we mean things like roads, buildings, powerlines, wind turbines - anything that isn't naturally there.

“One of the biggest impacts seems to be caused by things that would kill a bird outright, for example flying into a wind turbine, a building, being electrocuted on a powerline, hit by a vehicle or hunted.

"We found that exposure to these human-induced ‘direct mortality’ threats in the birds' wintering ranges are reflected in population decreases in breeding birds."

It is hoped the study in Global Ecology and Biogeography will help inform how best to target conservation efforts.

Lead author D.r James Gilroy, of the School of Environmental Sciences, said: "We know migratory birds are in greater decline than non-migratory species, but it’s not clear why.

“We wanted to find out where in their life cycles these migratory species are most exposed to human impacts."

Habitat degradation and global warming have also played a part in fueling the phenomenon.

The researchers identified 16 human-induced threats to migratory birds, including disturbance and collisions, conversion of land and climate change.

Advances in satellite imagery enabled them to be mapped across Europe, Africa and Western Asia.

Gilroy and colleagues also created the first global chart of its kind detailing hunting pressures.

It featured a total of 103 species including many rapidly declining species like the Turtle Dove and the Common Cuckoo.

The team calculated 'threat scores' for factors such as habitat loss and climate change, across breeding and non-breeding locations.

They then explored the relationships with population trends calculated from 1985 to 2018 by the Pan-European Common Bird Monitoring Scheme (PECBMS).

Co author Dr. Aldina Franco, also from the School of Environmental Sciences, added: "Our findings are important because we need to understand where declining species are being most impacted by humans across their seasonal migrations.

"Pinpointing where birds are most exposed to these threats could help us target conservation actions."