‘Decline in snake population responsible for crop losses’

November 3rd, 2008 • Related • Filed Under
Filed Under: A-Zoo News
Tags: Agriculture Sector • Ecological Changes • Ecological Zones • Natural Enemies • Poisonous Species • Population Of Snakes • Reptiles And Amphibians • Snake Population • Species Of Snakes • Zoological Gardens

Monday, November 03, 2008
Karachi

The sharp decline in the population of snakes due to ecological changes is harming the agriculture sector, as the population of rats and other rodents is on the rise, said former director of Karachi Zoological Gardens Dr A. A. Quraishy.

According to Quraishy, growing deforestation was responsible for the decline in the population of snakes. The minimum requirement of an environment-friendly country was to have 25 per cent forest cover. This is in stark contrast to arid zones in Pakistan, where only 12.5 per cent forest cover existed.

Due to a very sharp decline in forestation and destruction of natural flora, the forest cover had reduced to 0.2 per cent all over Pakistan, and reflected desertification, claimed Dr Quraishy. Owing to the absence of natural cover, fauna-like mammals, birds, reptiles and amphibians have disappeared from Pakistan, he observed.

In this context, the decrease in snake population is harmful for the agricultural sector. Snakes are necessary for good agriculture produce as they eat natural enemies of crops, including rats and rodents, he said. Field rats are reported to consume about 25 per cent agriculture crop, while the presence of snakes in agricultural fields is necessary to reduce their population and to ensure the safety of crops, he added.

He said that in rural areas the destruction of crops due to increase in population of field rats was alarming. He said that 30 to 50 per cent of the crop yield was being destroyed by rodents.

Both poisonous and non-poisonous species of snakes that were once found in the country are now endangered in quality and quantity in deserts, arid zones, grassy landscapes, marshes, fresh water and other ecological zones of Pakistan, added Dr Quraishy.

He said that the present destruction and deforestation in lower Sindh and Balochistan had driven snakes out of their lairs, rocky abodes, grassy and bushy patches in the hinterland. Desperate and confused, these snakes run into the marshy outback, even entering dry patches, derelict huts and abodes left by the locals in hundreds of villages in lower Sindh and in the coastal belt of Balochistan, he said.

He added that the vicinity of villages suited them best as they provided them with their staple food - the field rats - that dug under the soft land of the cultivated fields, orchards, farms and nurseries.

Desert lizards, some twenty different species of small, medium and large size, also resided in these habitats, where they found shelter, food and breeding sites, said Dr Quraishy. The sandy dunes, banks of rivers and streams also helped them to escape from enemies, to digest their meal or to bring down their escalated body temperature in scalding summer, he added.

He said that the flood and showers wash away the wild grasses while stunted bushes and seasonal creepers help snakes and lizards to survive through changing seasons of the semi-desert. In Balochistan, there was a period when they could find cool strata in holes that they would dig, so as to survive the harsh summers and to hibernate in the winter. The same holds true for Sindh, where snakes lived in the vast expanse of desert.

The sharp decline in the population of the poisonous, non-poisonous snakes and lizards has increased the rate of breeding of at least twenty species that destroys around 30 to 50 percent of crop yield in fields, barns, storehouses and godowns, he said.

Dr Quraishy said that a healthy population of these reptiles in the past has kept rat population low. In the current situation, the heavy loss of food grains has also increased poverty and escalated the Gross National Product (GNP) gap on a national scale, he added.

The incessant capture of snakes and lizards for laboratories and the unchecked export of these species are mainly responsible for the sharp decline of these very environment and agricultural friendly fauna, he claimed.

He claimed that the laboratories have been using them for decades to milk and exploit the venomous snakes to manufacture sera against snakebites. After milking, they are not released in their original habitats, he claimed.

Dr Quraishy said that the death toll by snakebites had diminished just a whiff but the gross imbalance between the prey-predator levels had increased deaths by malnutrition in villages that were eating less food than their minimum nutrition requirement.

The increased rat population robs their crops at every level – in the seedpods, in barns and in homes where they spoil a great deal by their smelly droppings and urine, he said.

Dr Quraishy said that snake charmers were also starving as they did not find enough cobras and colourful non-poisonous snakes with which they used to amuse spectators, who in turn used to pay them for their love of labour, melodious gourd flute and antics.