Succession and Colonization Pattern of Forensic Flies on Decomposing Carcasses of Indian Cormorant <i>Phalacrocorax fuscicollis</i> and Rohu <i>Labeo rohita</i>

Necrophagous Diptera are the first arthropods that inhabit carrion, enabling microbial decomposition and aiding in maintaining ecosystem balance, thus being important from ecological and forensic standpoints. This study compared dipteran fauna collected from Indian Cormorant (Phalacrocorax fuscicollis Stephens) and Rohu (Labeo rohita Hamilton) corpses in Kolkata’s urban environment. During this research, 1466 fly specimens were collected and identified from two carcasses comprising 5 families, 6 genera, and 9 species of forensic flies. In the avian carcass, dipteran families Calliphoridae, Muscidae, and Sarcophagidae were more abundant compared to the fish carrion. The common genera of dipterans that visited both carcasses were Chrysomya, Sarcophaga, Sepsis, Musca, and Atherigona. The dominant species of Diptera on both carcasses and throughout all the decomposition stages was Chrysomya megacephala Fabricius, thus indicating it as the most valuable species for post-mortem interval (PMI) determination in criminal, homicidal and wildlife poaching cases from the urban habitat of Kolkata.