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A study led by Purdue University Entomology Professor Michael Scharf, Ph.D. finds that small doses of imidacloprid, a neonicotinoid pesticide, can halt the normal functioning of termite behavior, leaving colonies vulnerable to disease and eventual death. While this effect may be celebrated by the pesticide industry as a victory for termite control, it has serious implications for the use of imidacloprid and other neonicotinoid pesticides on all eusocial insects, such as ants and bees.

A new study of the greater sage-grouse’s population finds that the bird’s numbers decreased 56 percent between 2007 and 2013, leading to the conclusion that the sage-grouse is at even greater risk than biologists thought and suggesting that conservation efforts are largely failing. The research, commissioned by the Pew Charitable Trusts and conducted by Edward (Oz) Garton, professor emeritus in wildlife ecology and statistics at the University of Idaho, represents the most comprehensive population update since 2011. "This report provides definitive evidence about the fragile state of the greater sage-grouse (Centrocercus urophasianus), an indicator species for the health of the interior West’s sagebrush region — where hundreds of other wildlife and plant species also live,” said Ken Rait, director of Pew’s U.S. public lands project. “We hope that this latest data will be used by the BLM and Western states to develop strong science-based land management plans that responsibly balance adequate protection of the sage-grouse and this important habitat with energy development and other land uses across the interior West.” The grim news comes as 11 Western states that include Utah gird for a possible listing of the bird this fall, with the U.S. Fish and Wildlife Service scheduled to make a decision in September.

The black swift (Cypseloides niger), a bird that nests in cliff-side habitats often associated with waterfalls and found in Banff National Park, is on the brink of extinction in Canada. The Committee on the Status of Endangered Wildlife in Canada (COSEWIC) met in Quebec April 26 to May 1 to examine the status of 20 species, ranging from lichen and fish to whales and wolves. The black swift, found in British Columbia and extreme western Alberta, was assessed as endangered. COSEWIC scientists say the black swift has experienced a large population decline over recent decades in the United States and in Canada, like many other birds that specialize on a diet of flying insects.They say the Canadian population appears to have declined by more than 50 per cent over a 40-year period between 1973 and 2012, now at an estimated 15,000 to 60,000 mature individuals.

Developmental neurotoxicity (DNT) studies are designed to investigate whether pre- or post-natal exposure to a toxicant affects neural development. Bayer conducted such a study with imidacloprid. Imidacloprid was administered in the diet to mated Sprague Dawley rats. The females were treated from gestation day 0 to 20 and then continued through the lactation day 21 at doses of 0, 100, 250 and 750 ppm, corresponding to an average daily intake of 0, 8, 19 and 54.7 mg/kg/day during gestation. The pups were indirectly exposed to imidacloprid for a total of 41 days (20 days in utero and 21 days via lactation). After weaning on postnatal day 21 pups were given untreated feed. Brain tissue from 10 pups/sex/group were analyzed on postnatal days 11 and 75. On post-natal day 11, female pups from the 750 ppm group had a decreased caudate putamen width (-5.5%) and a substantial reduction in the thickness of the corpus callosum (-27.6%). Morphometric brain measurements were not performed in the intermediate and low dose groups. The EFSA Panel on Plant Protection Products and their Residues (PPR) expressed concern about this pattern and although it does not directly demonstrate neurotoxicity, it cannot be dismissed, especially considering the magnitude of decrease in corpus callosum dimension. The major point of disagreement between Bayer Crop Science (BCS) and the PPR Panel is the interpretation of morphometric data. BCS contends that imidacloprid caused no morphometric effects in their DNT study; meanwhile BCS recognizes that their morphometric investigations were limited to the high dose and control groups. By contrast, the PPR Panel considered the morphometric data a source of concern and the lack of intermediate and low dose data as important missing information. Using the available data it is impossible to assess a dose-response relationship for morphometric changes. The level of uncertainty identified in brain morphometry precludes a robust characterization of the DNT potential of imidacloprid.

Researchers in Western University’s Department of Applied Mathematics have found a red flag beekeepers may be able to use to more accurately determine the health of their hives: the age at which forager bees are first sent out to gather food. Published recently in peer-reviewed journal PLOS ONE, a new study by PhD candidate Matthew Betti suggests that honeybee colonies threatened by pesticides, disease, parasites or other external forces tend to panic and release foragers from the hive earlier than usual. Responsible for gathering enough food for the hive to prosper, if the young bees fail to survive, the colony, already facing a serious threat, can deteriorate even more quickly. Under normal conditions, Betti found forager bees leave the hive around 14-days-old, but that number is smaller under adverse conditions. “It’s like sending a teenager out into the world,” he said. “The human may survive but a nine-day old bee is not likely to make it.”

Scientists have reported that a certain class of pesticides is turning bees into zombies by killing vital brain cells, leaving them unable to learn, gather food and reproduce. In a research report published in the FASEB Journal, scientists report that a particular class of pesticides called "neonicotinoids" wreaks havoc on the bee populations, ultimately putting some crops that rely on pollination in jeopardy. Specifically, these pesticides kill bee brain cells, rendering them unable to function and survive. "Our study shows that the neonicotinoid pesticides are a risk to our bees and we should stop using them on plants that bees visit," said Christopher N. Connolly, Ph.D., a researcher involved in the work from the Medical Research Institute at the Ninewells Medical School at the University of Dundee. To make their discovery, Connolly and colleagues fed bees a sugar solution with very low neonicotinoid pesticide levels typically found in flowers (2.5 parts per billion) and tracked the toxins to the bee brain. They found that pesticide levels in the bees' brains were sufficient to cause the learning cells to run out of energy. Additionally, the brain cells were even vulnerable to this effect at just one tenth of the level present.

Britain's hedgehog population is decreasing so rapidly that they are being driven towards extinction, a wildlife survey has confirmed. While hedgehogs were seen in two thirds of gardens (65 per cent) at least once in the course of the year, they were spotted regularly in less than a third of gardens (28 per cent) - and they were not seen at all in 20 per cent of back yards, the RSPB survey found. People were more likely to see a non-native grey squirrel than native hedgehogs, with squirrels spotted in almost three quarters of gardens (74 per cent) at least monthly throughout the year, according to information from hundreds of thousands of people. For the second year running, the RSPB asked people taking part in its annual Big Garden Birdwatch to tell them about the other wildlife they see in their garden through the year, with householders supplying information about 294,550 gardens.

A new study of the greater sage-grouse’s population finds that the bird’s numbers decreased 56 percent between 2007 and 2013, leading to the conclusion that the sage-grouse (Centrocercus urophasianus) is at even greater risk than biologists thought and suggesting that conservation efforts are largely failing. The research, commissioned by the Pew Charitable Trusts and conducted by Edward (Oz) Garton, professor emeritus in wildlife ecology and statistics at the University of Idaho, represents the most comprehensive population update since 2011. "This report provides definitive evidence about the fragile state of the greater sage-grouse, an indicator species for the health of the interior West’s sagebrush region — where hundreds of other wildlife and plant species also live,” said Ken Rait, director of Pew’s U.S. public lands project. In the Pew report, called "Greater Sage-Grouse Population Dynamics and Probability of Persistence," evidence pointed to a sharp decline in the number of breeding males — from 109,990 in 2007 to 48,641 in 2013 — and noted that populations across the bird's range are declining far beyond what even the best models forecasted.

For the first time, a research project has investigated how a neonicotinoid pesticide, clothianidin, affects both honeybees and wild bees under field conditions in agricultural landscapes. The study shows that honeybees can cope with exposure to the pesticide, but that it has a strong negative impact on wild bees. The researchers, from Lund University and Swedish University of Agricultural Sciences, in collaboration with the Swedish Board of Agriculture, have investigated how the neonicotinoid clothianidin affects domesticated and wild bees under Swedish field conditions. The research findings have now been published in the scientific journal Nature, and they show that the insecticide has a negative impact on wild bees. This is severe, because wild bees play an important role in pollination of crops. Wild bees are in Sweden bumblebees and solitary bees. “We saw a clear negative impact on growth and reproduction in bumblebee colonies near treated oilseed rape fields”, said Maj Rundlöf from Lund University, the coordinator and principal investigator for the field study.