Giant snail invasion

The courtyard of Retnamma’s house resembles a battlefield. There are dead giant snails strewn around, slime oozing from their brown conch-shaped shells. “These are the ones I killed last night with salt,” says the 60-year-old resident of Konni village in the foothills of the Western Ghats in Kerala.

Let the wind chase fire

Climate notes

THE Himalayas are warming at a rate higher than the global average. A recent study documents how this has affected cropping patterns and vegetation in the past 10 years.

Hard time for honeybees

Why are bees important to humans? The 20,000 or so species of bees are the principal pollinators of plants, both in gardens and in the wild. If you like having flowering plants around, for the most part you need to have bees around. There is a need to create awareness that pollinators need help. People should be encouraged to plant flowers and buy local honey and governments around the world should encourage beekeepers and regulate the use of pesticides in agriculture to minimise risks to honeybees. Interviewee:  May Berenbaum

At the mercy of chromosomes

PUZZLED why plants like congress grass, or Parthenium hysterophorus, spread fast? Any attempt to remove it is a failure as it would grow back quickly, while a plant like bracted arrowwood (Viburnum bracteatum) is slow to spread.

Weeding out belief

A PLANT species native to tropical and subtropical America was introduced in India as an ornamental shrub during 1809-1810. Called Lantana camara, this weed is now found all over the subcontinent. Similar is the case with freshwater species Eichornia crassipes (water hyacinth). This weed was introduced from Brazil during 1914-1916.

Clue to save turtles

MARINE biologists had almost given up hope of saving the green sea turtle in the 1980s following an uptick in a tumourcausing disease among the endangered species. They thought the deadly condition might drive the largest hard-shelled sea turtle to extinction.

Bee farms to shops

The journey of honey from bee farms to breakfast tables has become complex with time. From wild honey gatherers, honey supply has passed into the hands of cooperatives of individual beekeepers and then to big companies.

Measured efforts

The  greenback cuthroat trout once swam in large numbers through the South Platte and Arkansas Rivers in the US. Diversion of water for irrigation and introduction of non-native trout species such as rainbow and brown trout into the main rivers and brook trout into the small streams led to its rapid disappearance to the extent that the greenback was declared endangered.

Culled, efficiently

Invasive species are one of the biggest threats to biodiversity. Means of human transport has only made it easier for some to hitch a ride and colonize new regions.