The article by Kuensel titled Nine cranes killed by unknown predator and opinions expressed in its online forum all deserve appreciation for generating public interest and concern for crane conservation. The reported loss of nine cranes is, no doubt, a matter of concern for RSPN, the Department of Forest, and the general public. Therefore, it is our obligation to provide answers to the questions raised. Before we provide our explanations to the situation explained in the article, we would like to thank all those who have expressed concerns and for taking conservation dear to their hearts.

Black-necked Cranes have been migrating in and out of Bhutan since time immemorial. Their arrivals have always been a source of joy for many farmers, while their departure leave behind a sense loss, but their deaths in the past were hardly noticed. Ever since the establishment of RSPN in 1987, the number of the annual arrival of the cranes was monitored and recorded. However, it was not until the inception of the Integrated Conservation and Development Program (ICDP) in 1999 that a substantive scientific study on the cranes has been carried out (on the ecology and migration patterns of the cranes).

Over the last decade, the annual arrival of the cranes in Phobjikha valley has been steadily increasing from less than 200 to now over 300 birds. With the increasing arrival of the cranes in the valley, it has been observed that each winter the size of the natural roosting site became relatively smaller. Earlier, cranes in Phobjikha used to roost in shallow water. Cranes are known to roost in water to escape from terrestrial predators. The splashing sounds from an approaching predator enable the birds roosting in water to escape. With the roosting area in Phobjikha having undergone natural modification due to sedimentation, the artificially created pond proved relatively smaller as annual arrivals increased from 200 to over 300 now. Many birds are forced to roost on dry frozen ground on the periphery of the pond or opt for alternative roosts where predators can tackle them more easily than those roosting in water.

The loss of prey to predator is a natural occurrence in the wild. Such happenings are not new to the cranes as a prey species. What is new is the availability of information on such occurrences, with the increasing role of media and people’s access to media. Loss of individual cranes by predation has been recorded in Phobjikha last year and earlier too. Similar losses have been reported in the past in other habitats around the world. Recent reports from other habitats account loss of cranes to power line collisions, which is of more concern than losses to natural predators. In that context, loss of cranes to natural predators is an indicator of a vibrant ecosystem that is under human vigilance.

In same context, the deaths of nine cranes by natural predation and not by disease are not a cause for alarm. Experts explain such processes as ‘normal’ where weaker individuals from the population are withdrawn, thereby strengthening the gene pool of the surviving population. However, the loss of such a number from a population of endangered species is certainly a matter of concern. RSPN, in cooperation with the Ministry of Agriculture has seized every opportunity to screen the blood and carcasses of cranes for diseases. Necessary vigilance for unnatural occurrences is being undertaken by the concerned agencies like the Department of Forest, the Department of Livestock and Animal Husbandry, and Bhutan Agriculture and Food Regulatory Authority (BAFRA). RSPN, in collaboration with these agencies is also contributing to screening of blood and carcasses for bird flu virus. As of now, a few samples have been tested by the veterinary center of the Ministry of Agriculture and results have been found to be negative.

The level of attention given to the issue shows how aware and concerned Bhutanese are in relation to conservation of biodiversity and the environment. The Forest Department has responded by sending an independent team to investigate. The general conclusion is that, such predation may be acceptable as natural if it occurs within certain limits, after which management options with expert guidance need to be explored. The good news is that the predation has not persisted. The identification of the predator remains a priority, which will be done through scat analysis and continued vigilance in the habitat by concerned agencies.

Meanwhile, some questions remain to be answered. What is the predator? Why is predation an issue now than in the past? What are the management options? Can we assume the revival of rare predators such as the wild dogs (Dhole)? Could it be the domestic dogs that have been noted to inflict danger on cranes in other crane habitats around the world? Could it be the yellow throated marten? Or could it be the wild cat? A possible answer lies in the scat that has been collected for analysis. RSPN and the Ministry of Agriculture will continue to work together on these unanswered questions.

When it comes to reporting threats of bird flu, it will require multiple agencies and individuals to be vigilant. It is the responsibility of every agency and individual to report signs of occurrences to the concerned authority. RSPN will do its part!

Field Report, Phobjikha