Lower pollinator numbers herald crisis…..Ananda Banerjee
A decline in the number of butterflies and bees, major contributors toward global farm output, calls for urgent conservation steps
A decline in the number of butterflies and bees, major contributors toward global farm output, calls for urgent conservation steps
New Delhi: Red Pierrot, Common Lime, Plain Tiger, Blue Pansy or the Common Castor may be unfamiliar names to most Indians, although it is likely that most would have seen one or more of the fivethe most common butterflies found in India.
While it is unlikely that most people would notice their absence, it is almost certain that plants willbutterflies, such as these, help them reproduce.
The subcontinent has approximately 1,300 of more than 20,000 butterfly species known, said Kishen Das, a US-based lepidopterist. Thats about 6.5% of the global butterfly diversity.
However, the problem is that around 100 of the butterfly species found in India are nearing extinction, according to Surya Prakash, a professor at the department of life sciences at Jawaharlal Nehru University. Few are aware of the crucial pollination role the butterfly plays, which is second only to the honeybee, he adds.
Theres bad news on that front too.
Our observations in the Sundarbans have established that the population of bees as pollinators is decreasing, says K. Venkataraman, director, Zoological Survey of India?.
Pollination is the process that helps plants reproduce. From the consumption point of view, it is also the process that produces fruits, vegetables, pulses, and grainsany food, basically, that comes from a plant.
Around 70% of all food crops are pollinated by insects, according to the Food and Agriculture Organization. In Europe, the proportion is 84%. While no corresponding data is available for India, theres nothing to suggest that food crops here are pollinated by other means. This means that a decline in the number of pollinating insects could have catastrophic effects.
If human beings were to disappear tomorrow, the world would go on with little change, but if insects were to disappear, I doubt the human species could last more than a few months, wrote noted American biologist E.O. Wilson.
The impact of some insects becoming extinct isnt top-of-the-mind in a country where even conservation efforts are skewed towards large mammals, or mega-fauna, as Isaac Kehimkar, general manager (programmes) at the Bombay Natural History Society? and author of The Book of Indian Butterflies, terms it. Lack of knowledge and obsession with mega-fauna is killing entomology as a subject. It has become professionally unsustainable today as there is a fight for the same set of funds which inevitably go to the tiger or one of the mega-fauna species, he says.
To be fair, the emphasis on conserving pollinating insects is relatively recent, even in the US. These insects not only support humanity, but also maintain diversity in an ecosystem. Though there has been a growing appreciation for the ecosystem services provided by pollinators, it is only recently, when farmers in the US started finding their bee colonies missing, that people started wondering about what might happen to the worlds food production in the absence of bees, says S. Ramani, project coordinator, All India Coordinated Research Project on Honey Bees and Pollinators. The expected direct reduction in total agricultural production in the absence of animal pollination has been estimated to range from 3% to 8%, showing that agriculture has become more pollinator-dependent. It has been suggested that we may be in the middle of a global pollination crisis.
If no one has noticed it is because not a single bee has ever sent you an invoice, says investment banker and environmentalist Pavan Sukhdev. In his book, The Economics of Ecosystems and Biodiversity, Sukhdev puts the worth of insect pollination at $200 billion (around Rs. 10 trillion today) a year, or 10% of the value of the worlds agricultural output.
Still, Indian research isnt conclusive enough to establish a so-called pollinator crisis that is separate and distinct from the general decline in biodiversity, which is a global phenomenon. Even in Europe, a region better studied than most, about 250 plant species are grown as crops. Of these, about 150 are thought to be insect pollinated, but for most we do not know which insects pollinate them, or whether yields are being limited by inadequate pollination, wrote Dave Goulson in Bumblebees: Behaviour, Ecology and Conservation.
What is clear is that some pollinator species are under threat.
A report put out by the United Nations Environment Programme says: When large habitats are fragmented into small isolated patches, food sources become scarcer for resident animals. Populations may then decline to the point that they are no longer able to benefit plants. As certain wild pollinators need undisturbed habitat for nesting, roosting, foraging and sometimes specific larval host plants, they are very susceptible to habitat degradation and fragmentation in particular. Human activities have impacted the landscape through fragmentation, degradation and destruction of natural habitats and the creation of new anthropogenic ones.
To act on this information, people, especially policymakers, will have to increase their awareness of insect conservation, which is not easy because even basic science on insects is scarce. Even today, most species are undescribed and the distribution of described species is mostly unknown. To boost the public profile of insects, experts recommend better public information and marketing, including greater use of red lists of threatened species, and making sure insects are addressed in environmental impact studies.
In other words, Save the tiger, sure, but also spare a thought for the Indian honeybee.
Crucial transfer: The expected direct reduction in total farm output in the absence of animal pollination has been estimated at 3-8%.