Sun, 01 Jan 2012
Discover more about biodiversity and its impact on our lives.
Species - our food and medecine
- While most people depend mainly on domesticated species for their dietary needs, some 200 million depend on wild species for at least part of their food.
- More than 60 wild species have been used to improve the world’s 13 major crops by providing genes for pest resistance, improved yield, and enhanced nutrition.
- Since agriculture began about 12,000 years ago, roughly 7,000 plant species have been used for human consumption.
- Amphibians play a vital role in ecosystems, are indicators of environmental health, and are ‘hopping pharmacies’ being used in the search for new medicines. Yet 41% of amphibian species are threatened with extinction.
- In some countries, medicinal plants and animals provide most of the drugs people use, and even in technologically-advanced countries like the USA, half of the 100 most-prescribed drugs originate from wild species.
- More than 70,000 different plant species are used in traditional and modern medicine.
- Production of at least one third of the world’s food, including 87 of the 113 leading food crops, depends on pollination carried out by insects, bats and birds. This ecosystem service is worth over US$ 200 billion per year.
- A square kilometre of coastal ecosystem such as mangroves forests can store up to five times more carbon than the equivalent area of mature tropical forests. But these areas are being destroyed three to four times faster than forests, releasing substantial amounts of carbon dioxide into the atmosphere and the ocean, and contributing to climate change.
- Wild species are important in pest regulation. Bats, toads, birds, snakes, and so on consume vast numbers of the major animal pests found on crops or in forests.
- A single colony of Mexican Free-tailed Bat eats more than 9,000 kg of insects per night, targeting especially Corn Earthworms and Fall Armyworms, both major crop predators. Yet 18% of bat species are threatened with extinction.
- A single brood of woodpeckers can eat 8,000-12,000 harmful insect pupae per day, helping to maintain the health of forests, whilst in fruit plantations, insectivorous birds can make the difference between a bumper crop or a costly failure.
- Overfishing has reduced some commercial fish stocks by more than 90%.
- The Giant Manta Ray is the largest living ray, which can grow to more than seven metres in width. Manta Ray products have a high value in international trade and targeted fisheries hunt them for their valuable gill rakers used in traditional Chinese medicine.
- In China, 78 million dryland cashmere goats supply up to 75% of the world’s cashmere fibre.
- Eighty five percent of sturgeon, one of the oldest families of fishes in existence, valued around the world for their precious roe, are at risk of extinction.
- The regal Arabian Oryx which was hunted to near extinction, is now facing a more secure future thanks to captive breeding and reintroduction efforts. Its wild population now stands at 1,000 individuals.
- The Southern White Rhino subspecies has increased from a population of less than 100 at the end of the 19th century to an estimated wild population of over 20,000.
- The status of Przewalski’s Horse has improved from Critically Endangered to Endangered. Originally, it was listed as Extinct in the Wild in 1996, but thanks to a captive breeding reintroduction programme, the population is now estimated at more than 300.
- The Campbell Island Teal has benefitted from a massive programme to eradicate rats, plus captive-breeding of remaining individuals. The species has now returned to New Zealand’s Campbell Island and the majority of birds are now thriving, resulting in a reclassification of the threat status to Endangered.
Awe and wonder
- Tourists spend billions of dollars every year to watch birds or whales, or witness wildlife spectacles such as the great annual migrations in the Serengeti ecosystem of Tanzania and Kenya where 1.5 million wildebeest, 500,000 Thomson’s gazelle and 200,000 zebra cross the plain.
- Visitors to national parks, are drawn by the wildlife they see, and the thriving diving industry is largely based on the species of coral, fish, and other marine species that provide a colourful spectacle.
- King penguins are found in their thousands in the sub-Antarctic Crozet archipelago, which is nicknamed the “25 million bird island”. The density of the marine bird population there reaches a staggering 60 tonnes/km².
Into the unknown
- The oceans cover 70% of the planet but we know so little about life within them.
- A team of scientists including from IUCN are exploring seamounts—underwater mountains which rise to at least 1,000 metres above the sea floor. Seamounts are home to a rich biodiversity and act as a type of ‘bed and breakfast’ for deep sea predators such as sharks but face many serious threats from human activities.