BHUBANESWAR: Is the number of Irrawaddy dolphins on the decline in Chilika lagoon? The latest census report has thrown up a poser as the population of the endangered species appears to be on the downhill, if one compares the estimation outcome over the years.
This year’s census by Wildlife Wing has put the number of Irrawaddy dolphins in Chilika lagoon at 114. The enumeration was conducted on January 19 across six coastal divisions of the State where the total number of dolphins was found to be 469, including 163 Irrawaddy dolphins.While Chilika lagoon was found to be home to 114 of them, as many as 45 were spotted in Rajnagar Mangrove division. Irrawaddy dolphins are known to prefer estuaries and brackish water systems which explains their thriving habitat at Bhitarkanika. In Balasore, four of this species were detected.
In 2013-14, the number of Irrawaddy dolphins in Chilika lagoon was estimated at 158 followed by 144 the next year. No census could be carried out in 2015-16 due to inclement weather whereas the 2016-17 estimation put their number at 121.Though the numbers may point that the Irrawaddy population has thinned down in Chilika, census teams had sighted more than 150 of these small, shy dolphins during the enumeration last month. In Satapada region, at least 86 of them were spotted while 66 were seen in Balugaon side of the lagoon.
Now, that illegal prawn gheries have been demolished by Chilika Development Authority (CDA), sighting of these dolphins was much easier during the one-day census. “We will go in for a second monitoring of Chilika on February 24 during which both dolphin and bird population would be given a fresh look,” Chief Executive of CDA, Susanta Nanda said, when contacted.
Experts also say that exact population of Irrawaddy dolphins can not be assessed since they keep migrating. There are possibilities of them moving from coastal wetlands to sea and nearby habitats.
However, the fact that Bhitarkanika continued to hold a stable population of Irrawaddy dolphins is great news.
Apart from Irrawaddies, the estimation found a growing number of dolphins from other species. In 2015, the total dolphin population stood at 450 with the number of bottlenose estimated at 52 but this year, it has grown to 121. Of them, 92 were sighted in Bhitarkanika, 12 in Chilika, five in Puri Wildlife Division and 11 in Berhampur division.
Of the two species of humpbacks, Sousa chinesis or Indo-Pacific humpbacks were estimated at 116 while Indian humpback number was 69. Bhitarkanika has 108 Indo-Pacific and 62 Indian humpbacks. Of the 469 dolphins estimated, 307 were in Bhitarkanika alone.