Artificial nests protect birds, power grids in NW China's Sanjiangyuan

The Sanjiangyuan nature reserve in northwest China has set up artificial nests for raptorial birds represented by upland buzzard to ensure harmonious co-existence between wild birds and power transmission facilities.

Upland buzzard is a top predator in grassland ecosystems, which mainly feeds on small herbivorous animals such as pikas, voles and marmots. It is an indicator species of grassland ecosystems.

The Sanjiangyuan area, located in the heart of the Qinghai-Xizang Plateau and in the southern part of Qinghai Province, is home to the headwaters of the Yangtze, Yellow and Lancang rivers and thus known as China's "water tower."

A nature reserve was established there in 2000 to better protect natural resources and wild animals. With an average altitude of about 3,500 to 4,800 meters, the area is one of the most fragile and pristine ecosystems in the world, with plentiful rivers, diverse species and lush grasses.

Benefiting from its ecological advantages, the area is home to approximately 300 rare bird species, including more than 20 raptors such as golden eagles, saker falcon and upland buzzard.

With the construction of power supply networks on the plateau over the years, equipment like transmission towers and grids have stretched across the previously rarely visited Sanjiangyuan area. These dozens-meter tall transmission towers have become an ideal perch and nesting site for large birds that require expansive views for hunting.

These raptorial birds, which prefer high perches, often rest, nest, hunt or rear their young on transmission towers. The bird droppings and debris that fall while nesting can easily trigger circuit faults, affecting the stable operation of the lines.

According to local power supply company, bird-related faults account for up to 30 percent of the total circuit tripping incidents.

During the initial investigation of bird-related faults, the employees of a local power supply company had limited knowledge about raptorial birds living on the plateau. At the very beginning, they tried to keep upland buzzards away from the transmission towers by installing bird repellers.

"Repellers were effective in the first two or three months, but the birds adapted to the repellers a few months later. Due to the strong ultraviolet rays in this area, repellers become fragile over time, making it easy for upland buzzards to knock them down when landing," said Xu Wenqi, a former operation and maintenance worker of the State Grid Yushu Power Supply Company.

The attempt to use repellers was unsuccessful, but the power supply company still hoped to keep birds away from the transmission lines, as debris can fall onto the lines during the nesting process, which would trigger circuit faults. Even established nests can pose risks to the safe operation of the power grid if they are not sturdy enough to withstand bad weather.

The power supply company tried to move upland buzzards' nests to safer locations, but also failed.

After the failure of the first two attempts, the power supply company shifted approach, trying to make comfortable artificial nests for upland buzzards.

While seeking advice from local herders and experts, the company started to make suitable nests by themselves.

"The first generation of nests we made had a roof, as we were thinking that the birds could shelter from wind and rain, but no birds moved in after we set up them. Later, we learned about their habits and realized that adult upland buzzards have waterproof feathers, and when it rains, they would lie on the nest and protect the young birds with their wings, so there was no concern about water seeping in. Also, it is convenient for adult individuals to feed their chicks in open cup nests. Birds are very vigilant, and open cup nests provide a broader view. If they sense danger, they can fly away in any direction," said Sonam Tsering, a vehicle dispatcher of the comprehensive service center of the State Grid Yushu Power Supply Company.

The first batch of 200 artificial nests made by the power supply company were set up on transmission towers across the Sanjiangyuan area.

"We found some individuals settled down [in the artificial nests] after about 10 days since we set up them at the first [pilot] location. We were quite excited to capture footage of the first baby bird born in the artificial nest after two or three months in around July or August, as many people have contributed in the process. It was incredibly exciting for us to see new life hatched," said Xu.

Based on the experiences of setting up artificial nests at pilot locations, the State Grid Qinghai Provincial Power Supply Company continuously upgraded the nests to improve safety and comfort and set up them in areas with frequent bird activity.

After setting up artificial nests, the presence of birds in dangerous areas on the transmission towers significantly decreased. As a result, the tripping rate of 10-kilovolt lines caused by bird activities dropped by nearly 30 percent.