Climbing human population's food sources threatened by bumblebee population decline?

Editor's comment: This article was originally published as "Decline in some species along with over-abundance of humans" in Your Say.

The abundance of four common species of bumblebee in the US has dropped by 96% in just the past few decades, according to the most comprehensive national census of the insects. Bees in general pollinate some 90% of the world's commercial plants, including most fruits, vegetables and nuts. Coffee, soya beans and cotton are all dependent on pollination by bees to increase yields. It is the start of a food chain that also sustains wild birds and animals.

But the insects, along with other crucial pollinators such as moths and hoverflies, have been in serious decline around the world since the last few decades of the 20th century.

Abundance of four US bee species declines by 96 percent.

Scientists said the alarming decline, which could have devastating implications for the pollination of both wild and farmed plants, was likely to be a result of disease and low genetic diversity in bee populations.

According to the Centre for Ecology and Hydrology in the UK, three of the 25 British species of bumblebee are already extinct and half of the remainder have shown serious declines, often up to 70%, since around the 1970s.

Experts aren't sure exactly why the bee population is declining (although similar findings have been reported all over the world) but they believe it's due to a "combination of new diseases, changing habitats around cities, and increasing use of pesticides."

Hundreds of birds have dropped dead from the sky in Louisiana just days after a similar mysterious incident left scientists baffled in Arkansas.

The carcasses of around 500 red-winged blackbirds were found littering a quarter-mile stretch of road in Pointe Coupee.

Last week, about 83,000 dead and dying drum fish washed up along a 20-mile stretch of the Arkansas River, about 100 miles west of Beebe. Wildlife officials say the fish deaths are not related to the dead birds, and that because mainly one species of fish was affected, it is likely they were stricken by an illness.

At the same time US demographers now project that the world's human population may reach nine billion before 2050--in 2045. Right now on Earth, water tables are falling, soil is eroding, glaciers are melting, and fish stocks are vanishing. Close to a billion people go hungry each day. Decades from now, there will likely be two billion more mouths to feed, mostly in poor countries. There will be billions more people wanting and deserving to boost themselves out of poverty. ( Global population report - National Geographic )

The health of humans, like all living organisms, is dependent on an ecosystem that sustains life. Human populations are increasingly concentrated in urban ecosystems, and it is estimated that, by the year 2010, 50 percent of the world’s population will be living in urban areas. The human population is at an all-time high, and associated pressures of human activity have led to increasing degradation of the earth’s ecosystems.