With the arrival of autumn and winter, birds that breed in the northern latitudes migrate to our more moderate Southern areas. The verdant forests surrounding the Western Ghats, rushing streams, fields, ponds, lakes, wetlands and coasts are the final destination of these birds for the winter. When spring arrives, they return to their northern breeding grounds.
The intermingling of these winter birds with the existing resident birds, from October to March, makes it an ideal time to observe, study and enjoy the avian biodiversity of our region. Many international, national and state organisations seek the assistance of local bird observation groups to survey and conduct a bird census in winter. A couple of examples that come to mind are the Asian Waterfowl Census or AWC and the Great Backyard Bird Count or GBBC.
The AWC, while comprehensive, counts only water and water-associated birds during a specific fortnight.
The GBBC, whose origins are from the North America continent (US and Canada), tries to capture a snapshot of winter birds during a three-day span in February. While these two counts are extremely relevant locally, what they provide is a limited picture at a specific point of time in the annual calendar, when bird populations are at their peak.
Should one then surmise that the numerous resident birds left behind (there are many of them) are unimportant and not worthy of being enumerated? Of course, not.
In fact, the months from April to September provide bird watchers with a unique opportunity to conduct a survey of resident birds. Such stock taking at regular intervals, perhaps once a month, will provide valuable information on the population levels of our resident avian species.
Moreover, if these data are collected in a systematic manner over many consecutive years, further scientific studies could be conducted to analyse and understand the subtler movements that take place amongst them.
For example, the altitudinal movements of resident song birds before the arrival of the Southwest monsoon, or the various local movements that water birds undertake from one wetland to another or from the internal continent to the coast in search of appropriate breeding locations.
Amateur bird watchers can be very useful and important participants in the exciting field of citizen science. It is well established that hobbyist birdwatchers have provided a lot of useful information about bird populations in Europe and North America.
The recent Pongal Bird Count by Tamil Birders Group is a worthy start that can grow in stature and scope. All it takes to assemble such a group is people with similar interests. They can adopt a nearby wetland or a neighbourhood park. Once they study the area and establish the survey method, data must be gathered at least once a month over many years before a meaningful analysis can be undertaken.
In the interim, these groups would have enhanced their own knowledge and also put together valuable expertise for the community at large. In addition, these self-sustaining groups can provide crucial information for various land management and conservation decisions.
Get the timing right
While the AWC and GBBC are relevant for our area, the celebration of World Bird Migration Day in May is not. For most of Southern India, birds start their northward migration in the middle of March and it concludes by the middle of April.
Group size
The size of a birding group should be no more than 10 to 12 individuals for a particular area. If it exceeds that number, they could be split and designated to cover other locations.
Study other species
Self-sustaining Nature groups can also be set up for the survey of butterflies and bats, employing the same strategy.
Bird count
A monthly count of birds is being undertaken in the Perur-Sundakamuthur Lake by a group of bird watchers since March 2014.
