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Two new reports on Europe’s endangered fish and bird species were released this week by the International Union for Conservation of Nature (IUCN). The first report is itself a milestone: the first full assessment of all of Europe’s 1,220 marine fish species. The study found that 7.5 percent of those species were threatened with extinction. Worst hit, as we’ve seen before, were sharks, rays and chimaeras. A full 40.4 percent of those European species (known collectively as chondrichthians) face the threat of extinction and nearly that many have declining populations. The second report looked at all 533 bird species that spend at least part of their time in Europe and found that 13 percent are threatened. Four species have been declared regionally extinct in Europe. Others, such as the sociable lapwing (Vanellus gregarius), aren’t far behind. Another 28 species have been assessed as endangered or critically endangered on the continent. Most of these are also at risk through the remainder of their ranges.

We studied the effects of sublethal doses of imidacloprid on olfactory learning in the native honey bee species, Apis cerana, an important pollinator of agricultural and native plants throughout Asia. We provide the first evidence that imidacloprid can impair learning in A. cerana workers exposed as adults or as larvae. Adults that ingested a single imidacloprid dose as low as 0.1 ng/bee had significantly reduced olfactory learning acquisition, which was 1.6-fold higher in control bees. Longer-term learning (1-17 h after the last learning trial) was also impaired. Bees exposed as larvae to a total dose of 0.24 ng/bee did not have reduced survival to adulthood. However, these larval-treated bees had significantly impaired olfactory learning when tested as adults: control bees exhibited up to 4.8-fold better short-term learning acquisition, though longer-term learning was not affected.

On May 29th, the Day of the Honey Bee in Quebec, Équiterre, in collaboration with the David Suzuki Foundation, hosted a public talk presenting the results of the most important literature review on the impacts of neonicotinoïd pesticides, that kill pollinators. The comprehensive assessment of more than 1,000 peer-reviewed reports was conducted by the international Task Force on Systemic Pesticides, an international group of 50 independent scientists. The talk was given by Jean-Marc Bonmatin, researcher at the French National Centre for Scientific Research (CNRS) and Task Force vice-chair, and Madeleine Chagnon, PhD, associate professor at the Department of Biological Sciences at the Université du Québec à Montréal, who also participated to the Task Force. "As a scientist, I can now say conclusively that the evidence of harm is clear and points to the urgent need for action to reduce the quantities of these pesticides entering the environment," said Bonmatin.

The guild of ‘aerial insectivores’ – birds that specialize on feeding on flying insects – includes Whip-poor-wills, nighthawks, swifts, swallows, martins, and flycatchers. Early results from the second Ontario Breeding Bird Atlas indicated some startling declines and even range contractions for this guild. Now that the 2001-2005 Ontario Atlas is complete, the plight of aerial insectivores is gaining increasing attention. The patterns of decline are mirrored very closely by the Breeding Bird Survey, not only in Ontario, but also across much of North America. Early results from the second Maritimes Breeding Bird Atlas and data from the recently completed second New York State Atlas also point to similar patterns. The magnitude of the declines, especially within the past 20 years or so, is alarming. The proverbial clock may well be ticking down on many common species of aerial insectivores in Canada. In the last two decades alone, populations have fallen by over 70% in the case of Bank Swallow, Common Nighthawk, Chimney Swift, and Barn Swallow, and by over 50% for Cliff Swallow, Olive-sided Flycatcher, Eastern Wood-Pewee, Northern Rough-winged Swallow, Eastern Kingbird, and Purple Martin. Declines have been so severe that Chimney Swift, Common Nighthawk, and Olive-sided Flycatcher were recently designated as nationally Threatened species. Barn Swallow, Bank Swallow, and Eastern Wood-Pewee may not be far behind.

Many bird species commonly found in California have suffered steep population declines, as much as 96%, part of a nationwide trend, according to a study that for the first time combines 40 years of data. The study, combining the National Audubon Society's Christmas season bird counts with summertime surveys by the U.S. Geological Survey, documented declines of 75% to 96% in several California species, including the northern pintail, horned lark and loggerhead shrike. Greg Butcher, Audubon bird conservation director and analysis leader, said of the birds surveyed nationally, "about half are in decline and of these half are in significant decline." Overall, Butcher said, his organization is concerned about decreasing numbers of 200 to 300 kinds of birds. Because they have been so numerous, the birds that were surveyed often don't get the attention that small, endangered populations such as California condors have received. However, Gary Langham, Audubon California's director of bird conservation, said that although many bird populations may number in the millions, the large reductions that were documented are statistically significant. Kimball Garrett, collection manager for ornithology at the Natural History Museum of Los Angeles County, said that while the surveys must be interpreted cautiously, they are in line with other studies that show steep declines. "Some trends are just undeniable," he said. The evening grosbeak fared the worst in Audubon's California survey, with a 96% decline statewide. Nationally, grosbeak numbers fell from 17 million 40 years ago to 3.8 million today, according to both surveys.

A team of scientists from the North American Bird Conservation Initiative (NABCI) identified the 33 U.S. common bird species in steep decline: Northern Pintail (Anas acuta), American Wigeon (Anas americana), Cinnamon Teal (Anas cyanoptera), Greater Scaup (Aythya marila), Long-tailed Duck (Clangula hyemalis), Scaled Quail (Callipepla squamata), Northern Bobwhite (Colinus virginianus), Purple Gallinule (Porphyrio martinicus), Franklin’s Gull (Leucophaeus pipixcan), Herring Gull (Larus argentatus), Black Tern (Chlidonias niger), Yellow-billed Cuckoo (Coccyzus americanus) , Snowy Owl (Bubo scandiacus), Short-eared Owl (Asio flammeus), Common Nighthawk (Chordeiles minor), Chimney Swift (Chaetura pelagica), Loggerhead Shrike (Lanius ludovicianus), Horned Lark, Bank Swallow, Verdin, Varied Thrush, Snow Bunting, Cape May Warbler, Blackpoll Warbler, Wilson’s Warbler, Field Sparrow, Lark Bunting, Grasshopper Sparrow, Eastern Meadowlark, Rusty Blackbird, Brewer’s Blackbird, Common Grackle and Pine Siskin. These are common birds that do not meet Watch List criteria, yet according to long-term monitoring surveys are rapidly declining throughout their range. They have lost more than half their global population over the past four decades.

One of nature’s best scavengers is under serious threat in Africa, largely from poison. According to the first analysis of African vultures, populations of seven species have fallen by 80% or more over three generations. Most of these species may qualify as critically endangered. “The rates of decline stand out as being pretty rapid,” says conservation biologist Rhys Green of the University of Cambridge in the United Kingdom, who was not involved in the new analysis. The situation for African vultures, he says, “is not yet irrecoverable, but it is serious.”

The stingless bee Scaptotrigona postica is an important pollinator of native and cultivated plants in Brazil. Among the factors affecting the survival of these insects is the indiscriminate use of insecticides, including the neonicotinoid imidacloprid. This work determined the toxicity of imidacloprid as the topical median lethal dose (LD50) and the oral median lethal concentration (LC50) as tools for assessing the effects of this insecticide. The 24 and 48 h LD50 values were 25.2 and 24.5 ng of active ingredient (a.i.)/bee, respectively.

Integrated Pest Management (IPM) is a decision making process used to manage pests that relies on many tactics, including cultural and biological control, which are practices that conserve beneficial insects and mites, and when needed, the use of conventional insecticides. However, systemic, soil-applied neonicotinoid insecticides are translocated to pollen and nectar of flowers, often for months, and may reduce survival of flower-feeding beneficial insects. Imidacloprid seed-treated crops (0.05 mg AI (active ingredient) /canola seed and 1.2 mg AI/corn seed) translocate less than 10 ppb to pollen and nectar. However, higher rates of soil-applied imidacloprid are used in nurseries and urban landscapes, such as 300 mg AI/10 L (3 gallon) pot and 69 g AI applied to the soil under a 61 (24 in) cm diam. tree. Translocation of imidacloprid from soil (300 mg AI) to flowers of Asclepias curassavica resulted in 6,030 ppb in 1X and 10,400 ppb in 2X treatments, which are similar to imidacloprid residues found in another plant species we studied. A second imidacloprid soil application 7 months later resulted in 21,000 ppb in 1X and 45,000 ppb in 2X treatments. Consequently, greenhouse/nursery use of imidacloprid applied to flowering plants can result in 793 to 1,368 times higher concentration compared to an imidacloprid seed treatment (7.6 ppb pollen in seed- treated canola), where most research has focused. These higher imidacloprid levels caused significant mortality in both 1X and 2X treatments in 3 lady beetle species, Coleomegilla maculata, Harmonia axyridis, and Hippodamia convergens, but not a fourth species, Coccinella septempunctata. Adult survival were not reduced for monarch, Danaus plexippus and painted lady, Vanessa cardui, butterflies, but larval survival was significantly reduced. The use of the neonicotinoid imidacloprid at greenhouse/nursery rates reduced survival of beneficial insects feeding on pollen and nectar and is incompatible with the principles of IPM.