Bird Migration, their threat, and technology

In my childhood, the general practice of sending a letter to anyone was to write the return address alongside the delivery details. In case the letter was not delivered, a good samaritan would always post it back and would not rely on the Post office system to do this job. Something similar was promoted and perhaps gave rise to the initial world of citizen science where data was generated by people reporting sightings or observations back to the research lab.

Sometime at the beginning of 1900, a message was written on the band on Black-crowned night herons which read “Return to Smithsonian Institution.” The real reason for selecting this bird for tagging is not mentioned, but probably due to widespread distribution and visibility throughout the day as they hunt during the night might promote its easy observation by the public. Paul Bartsch's bird banding paved the way for the future of such studies and led to the formation of the American Bird Banding Association.

Bird Banding is a technique to understand the ecology of birds by putting a tag on them. Right from a thread tied on the legs to aluminum bands of different colors to fixing bands with satellite tracking, all these bandings have been used to study the bird population, migration, breeding ground, and habitat usage by birds. However, tagging/banding means catching hold of the bird which if not done properly can damage the bird.

In the 60s-70s Dr. Salim Ali, the famous ornithologist of India, did the bird banding and is said to have ringed multiple birds. Besides SACON, BNHS has also trained and developed guidelines for bird banding and the latter has a page to promote citizen science-tagged bird reporting . This amalgamation of technology and ecology brought forth some interesting information regarding birds.

Long-distance migration: In 2020, a cuckoo covered 12,000 km from southern Africa to its breeding ground in Mongolia. This long-distance route taken by the bird was very much appreciated, especially, at the time when the pandemic restricted humans within the political boundary. A successful migration of 29,000 km was reported by Amur Falcon from Manipur in 2020. Amur falcon conservation program is interesting to observe where the migratory route that the small raptor takes has India's northeast states, Manipur, Nagaland, Assam, and Meghalaya, as a stop/fuelling site before leaving for South Africa brought much evidence via this technology. There were incidences of hunting that threatened these birds. However, this successful migratory route has brought positivity to conservation communities as well as to the citizens who are now keeping track of the falcon's migratory route and supporting the conservation.

Scientific confirmation of the migratory routes: the migratory routes identification from satellite data not only identifies routes but also confirms the anecdotal information of the migratory path. Identification of these migratory routes helps policymakers in listing the conservation priority sites in a country and develop policies for the same. The Convention of Migratory Species identifies 9 global migratory flyways. Central Asian Flyway (CAF) is one of them where maximum migratory routes pass through India. CAF reveals that over 50% of the Important Bird Areas for migratory birds are not protected and others have complete or partial protection. It also reports limited information regarding bird population monitoring (during breeding, migration, and non-breeding periods). The reason for this limited data is the difficulty of covering all sites regularly for monitoring and assessment, especially the threat. Based on their national questionnaire, the "main threats" to habitats used by migratory birds during their annual cycle are listed in the report. However, this list does not directly account for transmission lines. Electrocution by powerline is mentioned for "Raptors (Pallas’s Fish-eagle, vultures), Waterbirds (Black-necked Crane and other cranes, storks, flamingos, swans,)" but identifying it as main threat and strategize for land protection is not mentioned.

In 2019, a joint study by Indian and Russian Scientists revealed that the Siberian migratory bird might be falling prey to transmission lines. The Ospreys were satellite-tagged and traveled 5,000 km to reach their wintering ground where one of the raptors died due to electrocution in central India. Gujarat is trying to find a solution and alternative to the undergrounding of distribution line cables as the death of migratory birds is not a newly identified threat. In 2010, as many as 400 demoiselle cranes got electrocuted in Kutch after they collided with power lines. In 2020, the death of a Himalayan Vulture due to electrocution in the Mudumalai Tiger Reserve pointed out the electrocution to not only a migratory bird (global concern) but to a raptor which is high on the agenda for national wildlife conservation. In Uttarakhand , recently vultures were satellite tagged to get “information about the habitat, location, migration, their route, living conditions related information". This tagging of birds can contribute to identifying the habitat usage and threats to these vultures in the Doon Valley.

Technology like satellite tagging has helped conservationists to identify and prioritize the conservation sites for the species. The anecdotal information on habitat usage by migratory species is not enough evidence to convince policymakers to develop legal protection for these habitats. However, satellite tagging and long-distance migration of birds not only bring an exchange of ideas and methods of global experts on conservation exchange but also put globally significant conservation programs on the pedestal of citizen science. The powerlines development is progressing across the globe. A legal document scientifically backed with information on conservation priority sites of migratory species would benefit from prioritizing the safeguards while developing these powerlines. These safeguards can be for avoidance as well as mitigation strategy and can be plugged into the legal compliance of the development projects.