Scientists have described 1 million species of insects so far, and estimate that at least 4 million species worldwide are still unrecorded. For people living in areas with ample wilderness and a plethora of biting mosquitoes that carry malaria and other diseases, a decline in insect populations might seem like an outlandish concern. But in areas with intensive industrialized agriculture, the drop in insect populations is worrying.
Bereits im Jahr 1962 wurde von Rachel Carson der stumme Frühling vorhergesagt, wenn die Industrialisierung der Landwirtschaft und die Nutzung von Chemikalien auf den Äckern fortschreiten: Ein Frühling ohne das vertraute Summen von Bienen, Hummeln, Fliegen, Käfern und anderen Insekten. Dieses Szenario droht nun Wirklichkeit zu werden, wenn wir nicht sofort handeln.
Recent monitoring studies in several countries have revealed a world-wide contamination of creeks, rivers and lakes with neonicotinoid insecticides, with residue levels in the low μg/L (ppb) range. At least two main areas of concern can be identified: reduced capacity for decomposition of organic debris by aquatic organisms and starvation of insectivores and other vertebrate fauna that depend on invertebrates as a major or only food source.
Most of New Zealand's native freshwater species are at risk of extinction as water quality faces "serious pressures", a Government report says. The report by the Ministry for the Environment and Statistics New Zealand, titled Our fresh water environment 2017, found nearly three quarters of native freshwater fish species are threatened by or at risk of extinction, as well as a third of native freshwater invertebrates and a third of native freshwater plants. It found nitrogen levels were worsening at more than half of the measured sites.
The River Irwell appears to have been polluted for a second time in three weeks. Countless fish and insects died following reports a pesticide which was poured down a drain and devastated a 25-mile stretch of the river from Rawtenstall into Manchester city centre earlier this month. Now a second incident has been reported on a section of the Irwell north of Bury. The incident has been reported to the Environment Agency. Mike Duddy, chief executive of the Mersey Basin Rivers Trust, said virtually no river life had survived the previous incident.
Regional Environment Awareness Cameron Highlands (REACH) president Ramakrishnan Ramasamy said most rivers in the highland, known for its tourism and agriculture, are heavily polluted. He said data from the Department of Environment (DoE) and the Drainage and Irrigation Department (DID) showed that only about 10 per cent of 123 rivers were in Class I and Class II, while the remainder were in Class III and Class IV. He also said three rivers had been declared biologically dead, and came under Class V of the classification.
New monitoring in the Bay Delta shows that the water is a soup of urban and agricultural insecticides, herbicides and fungicides. When combined, pesticides at sublethal levels can have deadly synergistic effects on fish. “The Sacramento River and San Joaquin River have been monitored for years, but historically there has been little monitoring in the Delta itself,” says Michelle Hladik, an environmental chemist who leads the USGS Pesticide Fate Research Group.
SALMON catches on River Tweed and its tributaries fell by seven per cent last year. A total of 7,680 fish were taken by rod and line during the 2016 season - down from 8,091 in 2015 – reflecting a year-on-year downward trend since 2013 when over 14,000 salmon were caught. There was an even sharper fall in the number of sea trout taken by anglers in 2016 – from 1,280 to 2,323 – the lowest catch in the past decade.
CORACLE fishermen on the River Teifi have reacted immediately to concerns about the falling levels of fish stocks by agreeing to return any salmon they catch. The Teifi Coracle Netsmen has also called on other anglers to adopt a catch and release policy after shock new figures from Natural Resources Wales (NRW) showed a sharp decline in the number of fish caught. There was just over 40 declared net catches of salmon on the river in 2015 compared to about 115 in 2014. Declared rod catches were down from 300 in 2014 to just over 200 in 2015.
A recent analysis by the European Commission's Joint Research Centre (JRC) shows that 93% of the assessed fish stocks are overexploited, and a number of them are on the verge of depletion. In addition, the Mediterranean Sea has lost 41% of its marine mammals and 34% of the total fish population over the past 50 years. An estimated 10 000 to 12 000 marine species inhabit the Mediterranean Sea, but this extraordinary biodiversity is in grave danger. Further delays in concerted action could result in irreversible damage and a collapse of key stocks that are essential to the fisheries sector.