Raptors make power towers their home

Raptors make power towers their home


White-bellied sea eagles are starting to establish residences atop power towers that house high-tension cables in India, following the example set by their relatives in Australia and Thailand.

White Bellied Sea Eagles

The white-bellied sea eagle (Haliaeetus leucogaster) is a species classified within the Accipitridae family. Its broad coastal range includes parts of Sri Lanka, coastal Southeast Asia, southern China, and Australia in addition to the Indian coast from Mumbai to eastern Bangladesh. On the IUCN Red List, this extraordinary bird has the conservation rating “least concern.” Its behaviours, like being nocturnal and monogamous, as well as its diet, which primarily consists of fish and sea snakes, show how well-adapted it is to a marine environment.

Where do these birds nest usually?

  • Near seacoasts, tidal creeks, and estuaries, towering trees are often preferred nesting locations for white-bellied sea eagles (Haliaeetus leucogaster). 
  • They can construct their nests in these natural environments, which give them convenient access to their main food sources of sea snakes and fish.
  •  Recent investigations show that these eagles are also becoming accustomed to exploiting man-made objects like powerline towers when good natural nesting places are hard to come by.

What are the effects of birds nesting over towers?

Positive Effects

  • Predator Protection: Nesting on towers may offer protection against predators that lurk on the ground and may pose a threat to eggs and young in typical tree nests.
  • Elevated Viewing Points: Towers provide elevated platforms that can help with hunting and keeping an eye on prey, especially for raptors like eagles.
  • Nesting Site Availability: Man-made structures can operate as substitute nesting sites when natural ones are scarce owing to habitat loss or other reasons, potentially boosting the number of bird species that can raise their young.

Negative Effects

  • Human Disturbances: Towers are frequently located close to human activity, which might cause interruptions during nesting. Stress caused by people, construction, and noise may cause nesting birds to abandon their nests or have less successful reproduction.
  • Risks of Collisions and Electrocution: Birds that nest on powerline towers run the risk of electrocuting themselves if they come into touch with live wires. Nestlings and fledglings run the risk of unintentionally colliding with surrounding structures or falling onto powerlines.
  • Limited Nesting Space: Some tower structures might not give birds enough room to nest properly, resulting in smaller or less secure nests that might not fully protect eggs and chicks from the weather.
  • Chemical Exposure: Depending on where the tower is located, nesting birds may be exposed to pollutants, chemicals, or other toxins that are nearby. This exposure could have an impact on both the health of the birds and the health of their young.
  • Behaviour Modification: Nesting on towers may alter the birds’ natural behaviour, including how they interact with other species and how they contribute to the ecosystem.

What is the way forward from this situation?

  • Site selection and Design: Designing towers with bird-friendly characteristics can lessen the risk of electrocution and crashes. Site selection. This might entail secure nesting platforms, insulated wire covers, and perch deterrents.
  • Regular Monitoring: Keep an eye on nesting areas to evaluate the condition and well-being of the birds and their nests. This can aid in early detection of potential issues and enable prompt response.
  • Outreach and Education: To increase public understanding of the value and dangers faced by tower-nesting birds. To reduce disturbances, promote appropriate conduct near nesting locations.
  • Environmental Assessments: Before building additional towers, do environmental impact analyses to determine any potential effects on bird populations and nesting habits.
  • Mitigation Techniques: Take action to reduce human disruptions around nesting areas, especially during delicate times like reproduction and chick raising.
  • Research and Collaboration: Collaborate with academics, environmentalists, and the appropriate authorities to compile information on bird populations, nesting success, and potential dangers. Better management techniques can be informed by this information.