VADODARA: With temperatures taking a slight dip with approaching winter, Barodians often flock the riverbanks to view the majestic crocodiles sunbathing in the open. But, in the coming days they will be able to do more than view – they will be able to greet individual reptiles by their names with help of a simple photograph!
Vadodara, which enjoys being the only Indian city having a thriving breeding crocodile population of close to 270 that has made Vishwamitri river their home, will now have its own database for the crocodiles too.
A software is being developed for the first time on mugger crocodiles. Photo identification in animal studies has been a widely used method for identification of individuals in many species, based on unique natural markings and patterns.
Tanisha Dagur, a final-year masters student of MS University’s zoology department, has now completed a pilot study which has achieved success in capturing the photographic evidences of the reptiles, under the guidance of Dr Ranjitsinh Devkar, assistant professor of zoology.
“HotSpotter (HS) PID program has been successfully used internationally for green sea turtle and even frogs in the Ganga stream in Uttarakhand. But it was for the first time, that we evaluated its accuracy for mugger crocodiles,” said Dagur.
Dagur conducted the pilot study on two patches – Bhimnath bridge and Vadsar area. During the course of the study, she captured photographic images of nearly 35 crocodiles basking near Bhimnath bridge and also another 15 crocodiles that were basking near Vadsar.
“There are blotches on crocodiles through which we can identify them individually. If one individual has three dark patches and one light patch, another reptile would have a different set of patches,” she said. The photographs clicked during the study are uploaded on the software which uses artificial intelligence (AI) to establish their unique features and identity.
“It is through this process that you come to know whether you had clicked the photograph of the same individual or a different one,” she said.
“This software would subsequently create a database of all the crocodiles sighted. The feasibility and accuracy of the study has been found to be reliable. Since, it is a non-invasive technique, it can replace the traditional mark-recapture technique in which a crocodile has to be trapped and marked. The mark-recapture technique which is used in some countries like Australia puts a lot of stress on the animal,” said Devkar.
“Use of a software and photographs can minimize the stress and can facilitate the studies in a non-invasive way,” he said.
Having a complete database can help in studying the short and long distance migration of the crocodiles. “We can also come to know if some of them are trans located and if they reappear at the same place,” he said.