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Barn owls (Tyto alba) suffered their worst year on record in 2013. Results from barn owl monitoring schemes around the UK revealed the number of sites where nesting took place last year was significantly down in every area compared to previous years, and some surveys found no nests with eggs in at all. Overall the number of occupied nests was down 71% on the average across all previous years, according to the Barn Owl Trust, which collated the information from 21 independent groups stretching from Jersey in the Channel Islands to south-west Scotland. A survey in Berkshire which normally finds 14 nests in use and a surveyor in Yorkshire who normally finds 25-30 occupied nests both found none at all, while surveys in Buckinghamshire and Sussex were both down more than 90% on normal levels. Conservationists described the situation as the "worst year ever recorded" for the flagship farmland species. Almost four times as many dead barn owls were reported to the British Trust for Ornithologyin March 2013 than normal and by mid-April it was possible that there were fewer barn owls alive in the UK than at any time since records began, the report said.

Integrated pest management programs (IPM) promote the use of multiple cultural, biological, and chemical tactics to reduce the abundance of pest insects, while conserving pollinators and beneficial insects. Much research has focused on the impact of systemic neonicotinyl insecticides on the colony health and foraging behavior of bees, but few papers considered these impacts on pollen and nectar-feeding beneficial insects, such as parasitoids, lacewings, lady beetles, and butterflies. Contact insecticides only contaminate pollen and nectar of flowers that are open at the time of spraying. In contrast, soil-applied neonicotinyl insecticides are translocated to pollen and nectar of flowers for a longer duration, often months. Neonicotinyl seed-treated crops (imidacloprid, 0.11 mg/canola seed and 0.625 mg/corn seed) translocate less than 10 ppb to nectar and pollen. However, higher rates of soil-applied imidacloprid are used in urban landscapes and nurseries (270-300 mg/3gallon pot, 67g imidacloprid applied to soil surface for 24 diam. tree), which should result in residues higher than the 10 ppb in nectar and pollen compared to seed-treated crops. This study shows that the translocation of imidacloprid from soil (300 mg) to flowers of Asclepias curassavica resulted in imidacloprid residue in nectar of 6,000 ppb for 1X and 10,000 ppb for 2X treatments. A second imidacloprid soil application 7 months after the first resulted in residues of 21,000 ppb in 1X and 45,000 ppb in 2X treatments. Consequently, landscape use of imidacloprid applied to flowering plants can result in 697 to 1,162 times more imidacloprid in milkweed nectar compared to a seed treatment, where most research has focused. These higher residue levels caused significant mortality in both 1Xand 2X treatments at day 12 in three lady beetle species, Coleomegilla maculata, Harmonia axyridis, and Hippodamia convergens, but not a fourth species, Coccinella septempunctata. Survival and fecundity of two nymphalid butterfly species, monarch, Danaus plexippus and painted lady, Vanessa cardui, were not reduced when free-ranging butterflies foraged on 1X and 2X treated milkweed plants or when butterflies were force-fed lower amounts of imidacloprid (0 ppb, 15 ppb, or 30 ppb imidacloprid). However, larval survival was significantly reduced on plants treated with soil-applied imidacloprid at1X and 2X treatments. Consequently, the use of systemic, neonicotinyl insecticides, such as imidacloprid, increased the insecticide’s duration in pollen and nectar, and increased the insecticide’s exposure to beneficial insects, thereby increasing the risk of mortality.

Exposure even to low levels of imidacloprid, a widely used pesticide, can harm the central nervous system of bees and may be a reason behind the global bee colony collapse, a National Taiwan University research team said yesterday in Taipei. Reports from around the world in recent years have shown that the population of wild bees has rapidly declined in many parts of the world. As bees contribute to the pollination of many crop species, ensuring production of seeds in many flowering plants and playing an important role in the ecosystem, many scientists are concerned about the rapid decline in bee colonies.

The very same pesticides accused of causing massive declines in honeybee populations are just as culpable in the loss of songbirds, finds a new report published by the American Bird Conservancy. The pesticides in question, neonicotinoids, are based on nicotine, a natural insecticide, which causes paralysis and, eventually, death in both insects and non-target animals, such as honeybees and songbirds. Introduced in the early 1990s, neonicotinoids are now the most widely used insecticides in the world. And that popularity carries a heavy burden, the report found. After analyzing more than 200 studies conducted by both independent and industry-funded scientists, the authors called for the Environmental Protection Agency (EPA) to ban these pesticides' use until a more thorough investigation into their safety is conducted. "A single corn kernel coated with a neonicotinoid can kill a songbird," said Cynthia Palmer, coauthor of the report and pesticides-program manager for the conservancy, in a statement accompanying the report. "Even a tiny grain of wheat or canola treated with the oldest neonicotinoid—called imidacloprid—can fatally poison a bird. And as little as 1/10th of a neonicotinoid-coated corn seed per day during egg-laying season is all that is needed to affect reproduction."