Rhododendrons, Possibly the Most Water from Mountain Streams
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Sanctuary | Field Biology More at www.sanctuaryasia.com | Field Biology The alarm went off, as always, of the beautiful, purple-coloured Iris at 4 a.m. The first thing I did was to flowers. The Iris plant is a food source head for the door to check out the for many birds and insects that rely day’s weather so I could plan my on the tubers and nectar during the schedule, which would inevitably be monsoons in preparation for the harsh determined by the nature of the clouds. winter ahead. In Sikkim, a small region in the Eastern The long hike offered me stunning Himalaya, everyone’s life had to be landscapes and views of spectacular adjusted to unpredictable weather. In Himalayan species including musk deer, my case, I quickly discovered that at Himalayan Monals, and Blood Pheasants. high-altitudes, a field researcher had These animals are more active early to take advantage of every sunny in the morning and through my study day, particularly if she was studying period I was often lucky to see them plant-pollinator interaction involving walking through their forests, or drinking Rhododendrons, possibly the most water from mountain streams. When exquisite flowers on the planet. we reached the first research plot, I I work in the Kyongnosla Alpine saw Rhododendron thomsonii trees Sanctuary in Eastern Sikkim, in a tiny laden with bright, blood-red flowers, an protected forest of 31 sq. km. located incredible picture postcard view against at an elevation ranging from 3,200 the backdrop of the snow! This is where to 4,200 m. Despite its tiny size, Sonam and I took up our position, near a Kyongnosla boasts a rich diversity of tree in full bloom. flora and fauna. My study area has mixed Within a few minutes, the cold that stands of conifers and Rhododendron had been kept at bay while walking trees and subalpine shrubs, with dwarf began to creep up on us. My nose and Rhododendron bushes and conifers in fingertips went numb. Sonam began the upper alpine reaches. grumbling about how tough it was even Though wild rhododendrons to write down notes and I wondered if are distributed in most parts of the any wildlife would even visit the flowers. Northern Hemisphere, the main focus Just as our patience and tolerance began of diversity is in the Himalaya from to run low, the first sunrays made their Uttarakhand, Nepal and Sikkim to appearance. With the welcome warmth western China and in Southeast Asia. enlivening us, we focussed on the flowers, and almost instantly saw a small, IN THE FIELD greenish bird with a long beak hovering On the first day, Sonam, my field near the tree. Before I could focus my assistant, and I started out from binoculars to confirm its identity, a the field station located at 3,200 m. second bright-coloured bird flew into at 5 a.m. so as to reach the field site view. I could see instantly that it was a before the pollinators arrived at the Fire-tailed Sunbird, with its characteristic blooms. Slowly, and with measured steps and very spectacular long, red tail, we ascended the snow-covered slopes. pointed beak and multi-coloured body. I forgot the cold as I watched it flit from It was hard work, but the excitement flower to flower, dipping in every once in of actually beginning fieldwork for my a while for its nectar reward. Only later doctoral degree dissertation filled me did I realise that the green-coloured bird with purpose. After a 45-minute walk, was the female sunbird. They tend to we had ascended to around 3,500 m, move in pairs and are generally the first and Sonam gestured silently to point out to visit the rhododendrons each day. a musk deer and a Himalayan Monal just RHODODENDRONS 15 m. away from us. I was smitten. Both creatures looked stunning contrasted Rhododendron thomsonii is native to India, against the whiteness of the snow, and Bhutan, Nepal and the Xizang area in China. BEYOND JUST BEAUTIFUL FLOWERS It is named by one of the greatest British seeing them together was indescribable. botanists of the 19th century, Sir Joseph Dalton I observed the pheasant scratching with Hooker, after his close friend Dr. Thomas its long beak and claws at the snow- Thomson, who was his travelling companion in Text and Photographs by Shweta Basnett covered ground in search of tubers the Eastern Himalaya. 60 Sanctuary Asia, December 2013 Sanctuary Asia, December 2013 61 Sanctuary | Field Biology More at www.sanctuaryasia.com | Field Biology A PERFECT BIRDING MORNING The day whizzed by as I recorded bird after bird species at the flowers. The thrushes, decidedly larger than the sunbirds, came in a party of five or six and spent more time on the flowers. They give out four to five different calls as they mimic other birds. When the tiny warblers arrived, I saw them appear in singles and across an elevation range of 3,200 to 4,200 m. Studies have revealed that birds are attracted to crimson-coloured flowers and over the course of my study, I saw a similar pattern. There were other rhododendron species that were flowering simultaneously such as R. campanulatum (purple flowers) and R. hodgsonii (pink flowers), but these were secondary choices for the birds. Of course, all birds are opportunistic feeders and they would move to less- preferred flowers once the red blooms After a harsh winter, when food sources in forests dwindle, Rhododendrons are the first tree species to bloom. Understandably a myriad life forms began to wilt. The shifts in the timing make a bee-line for these flowers. Rhododendrons also provide fringe benefits – the understory shrubs provide good habitat for the Blood Pheasant Ithaginis cruentus (left) and the Himalayan Monal Lophophorus impejanus (right) that usually feed on tubers found under the ground. of flowering from lower to higher altitudes helped the birds by distributing During the course of my field study, return are fed by these flowers. Nature Rhododendron Festival in honour of the availability of resources. All these I also observed beetles, wasps and ants is filled with such examples of win- the trees. birds visited a few specific tree species on the flowers. win strategies, perfectly crafted as There is, however, still a yawning through the day, and repeatedly visited The process of pollination is mutualistic relationships. gap in our understanding of the ecology similar trees at intervals. Key factors different in various rhododendron Wild species and humans living of Rhododendrons and now is when we that governed the choice of flowering species. In those with tubular flowers, around rhododendron habitats must have rules, regulations and laws species and quantum of nectar obtained the nectar lies in the bottom, or corolla have always understood the value that prevent over-exploitation. After were the beaks and body sizes. And tube, and can be reached only by of this incredible plant, but of late all, we surely must not allow life-giving when beak sizes were not conducive to visitors with long proboscises. In other the government too seems to have rhododendrons to be loved to death… the flower shapes, the birds stole nectar species the long stamens and pistils woken up to the significance of the for this would seriously impact wild by punching small holes at the base curve upwards so they can easily come flowers and has actually instituted a species up and down the food chain. y of the flower, after which, of course in contact with the pollinator. In yet the flowers would wither and die. It was interesting to observe how some others, coloured dots and blotches birds easily and ‘legitimately’ obtained on the corolla lobes act as nectar- nectar from certain flowers, and acted guides. Research suggests that most as nectar robbers with other species. hymenopterans follow these dots to The active robbers were largely finches reach the nectar. and tits. After a harsh winter, when forests offer virtually no food resource, POLLINATORS COME IN ALL Rhododendrons are the first tree SHAPES AND SIZES species to bloom. Understandably they therefore support myriad life forms. I Apart from birds, insects including have even recorded pikas feeding on bumblebees, flies and moths fallen petals of R. campanulatum. Much were clearly the most important later in June, I came across several TOP When beak sizes are not conducive to the flower shapes, the birds steal nectar by rhododendron pollinators in my field nests with juveniles of different birds punching small holes at the base of the flower. This Gold-naped Finch Pyrrhoplectes epauletta site. They creep over the stamens on the trees – this actually coincided is robbing nectar from Rhododendron thomsonii. and stigma to get to the base of the with the peak Rhododendron flowering. MIDDLE Insects, such as this bumble bee on a Rhododendron cinnabarinum flower, are nectar seekers too. Some species eliminate the effort of moving between petals and short-circuit the blossom. The insect is brushed with This floral species is without doubt one process by using powerful jaws to chew a hole and suck out the nectar using their short tongues. pollen, which it then transfers to the of the most important food sources ABOVE The author saw tiny warblers such as this Lemon-rumped Leaf-warbler Phylloscopus stigmas of flowers. Interestingly some that help to maintain and sustain the chloronotus, arrive in singles and across an elevation range of 3,200 to 4,200 m. The bird in rhododendrons are also blessed with biodiversity of this Himalayan region. this image has already visited the flower as the cream-coloured pollen are clearly seen on its long stamens that project above the But it’s a fair exchange.