English

English

Hedgehog population may have halved in just five years

Hedgehog numbers could have dropped by as much as a half over the past five years, warns University of Sussex Professor Fiona Mathews ahead of the launch of a major new survey into their current population levels. She warned that a shortage of food could be a key reason for the hedgehog decline due to the conversion of lawns into parking spaces and the high use of pesticides in gardens.

Neonicotinoids reduce the strength and duration of a bumblebee’s buzz, which impairs foraging

Ecologists at the University of Stirling in Scotland have found that neonicotinoids reduce the strength and duration of a bumblebee’s buzz. Their study was published this week in the journal Scientific Reports. Buzzing is more important than you might think. The vibrations of a bee's wingbeat help it shake pollen from flowers and onto its body. This pollen then gets deposited on the next flower the bee visits, resulting in pollination. Less buzzing equals less pollination, and reduces the bees' ability to forage for themselves.

Neonicotinoid insecticides impair foraging behavior, navigation, learning, and memory in honey bees

The decline of pollinators worldwide is of growing concern and has been related to the use of plant protecting chemicals. Most studies have focused on three neonicotinoid insecticides, clothianidin, imidacloprid and thiamethoxam, currently subject to a moratorium in the EU. Here we focus on thiacloprid, a widely used cyano-substituted neonicotinoid thought to be less toxic to honey bees and of which use has increased in the last years. Honey bees (Apis mellifera carnica) were exposed chronically to thiacloprid in the field for several weeks at a sublethal concentration.

In the last two decades there have been an alarming number of amphibian extinctions

Amphibians, a unique group of vertebrates containing over 7,000 known species, are threatened worldwide. A 2004 global assessment found that nearly one-third (32%) of the world's amphibians are threatened, representing 1,856 species. Amphibians have existed on earth for over 300 million years, yet in just the last two decades there have been an alarming number of extinctions, nearly 168 species are believed to have gone extinct and at least 2,469 (43%) more have populations that are declining.

Thiamethoxam alters honey bee activity, motor functions, and movement to light

Honey bees provide key ecosystem services. To pollinate and to sustain the colony, workers must walk, climb, and use phototaxis as they move inside and outside the nest. Phototaxis, orientation to light, is linked to sucrose responsiveness and the transition of work from inside to outside the nest, and is also a key component of division of labour. However, the sublethal effects of pesticides on locomotion and movement to light are relatively poorly understood. Thiamethoxam (TMX) is a common neonicotinoid pesticide that bees can consume in nectar and pollen.

Imidacloprid and chlorpyrifos insecticides impair migratory ability in a seed-eating songbird

Birds that travel long distances between their wintering and breeding grounds may be particularly susceptible to neurotoxic insecticides, but the influence of insecticides on migration ability is poorly understood. Following acute exposure to two widely used agricultural insecticides, imidacloprid (neonicotinoid) and chlorpyrifos (organophosphate), we compared effects on body mass, migratory activity and orientation in a seed-eating bird, the white-crowned sparrow (Zonotrichia leucophrys).

The Western Ghats have been witnessing an unusual number of frogs with deformities

Scientists and public health experts are alarmed by the phenomenon, which they suspect to be symptomatic of underlying toxicity in the environment and the food chain. “Missing eyes, deformed hind legs, missing limbs, extra limbs, partial limbs, limbs that are bent or bony, and abnormally thin or weak limbs are some of the reported frog abnormalities in the Western ghats,” said Dr. S. Muralidharan from the Division of Ecotoxicology at Salim Ali Centre for Ornithology & Natural History.

Steelhead stocks are rock-bottom in British Columbia

Steelhead anglers may have to start looking for another fish to catch. Four groups have released a joint statement sounding the alarm about the decline of steelhead numbers returning to B.C. rivers. The focal point of that concern is the Thompson River, a major tributary of the Fraser River. Where it once supported a thriving recreational steelhead fishery of 4,000 spawners in the mid-1980s, today the Thompson River has about 250 spawners projected for 2018.

Canadian fish stocks are at risk of collapse

Some fish stocks in Canada are at risk of collapse. Some estimates put the overall decline of marine populations at 50 per cent of levels in the 1970s, although the numbers vary depending on the species and its location. Oceana Canada, a scientific research and lobby group, just released its first audit of 159 separate marine fish stocks and found 26 in critical condition, 22 of those in Atlantic Canada.