Utility of DNA barcoding for identification of bird-strike samples from India

Bird strikes usually occur due to the entry of aircraft into the bird layer, i.e. the region up to which birds fly in the sky and are common during landing or takeoff 1. Along with the financial losses, bird strike also reduces the mission capability of the crew, loss of flying hours, permanent damages to the aircraft and importantly , it is always associated with the risk of mortality 2–6. The strategies to reduce the chances of bird strike involve habitat modifications, auditory and visual deterrents, avian radar system and changes in aircraft flight time and route. To implement these strategies, identification of the species involved in the bird strike is important. However, due to the impact of bird strike, the bodies of the birds are damaged beyond recognition. Usually the remains of the birds after a bird strike only include a smear of blood, feathers or tissues. Species identification based on feather morphology and keratin electrophoresis often fails to identify most of the reported bird-strike cases 2,7–10. DNA barcoding using mitochondrial Cytochrome c oxidase I (COI) gene has been routinely used for species identification 11. This technique depends entirely upon the nucleotide sequences of the COI gene and hence species identification is possible from any part of the body, even if it is damaged beyond recognition. Usually the COI gene sequence of the sample under question is generated and compared with the COI gene sequence database. All over the world large-scale efforts are being made to identify bird-strike samples using DNA barcoding 12–15. It is estimated that the aviation industry in India lose approximately Rs 30 billion/year due to bird strike 16. Despite their impact on the Indian aviation industry, no attempts are made to identify bird-strike samples using DNA barcoding. In the present study, we have evaluated the utility of DNA barcoding for species identification of birds involved in bird-strike incidences. We received 52 bird-strike samples from the Indian Navy from 2011 to 2014. In most of the cases, samples were collected on Whatman FTA cards (unless mentioned otherwise). A small piece of FTA card was utilized for DNA isolation using QIAamp ® DNA micro kit (Qiagen, Stanford, CA, USA). Samples for which DNA was not obtained in the first attempt were repeated twice (Table 1). PCR amplification of COI gene was done using primers mentioned by Dove et al. 12. The PCR products were sequenced using forward …