English

As wild salmon populations have declined dramatically, Fish and Game New Zealand (FGNZ) is hosting a symposium to discuss the problem. FGNZ councillor Matthew Hall, of Ashburton, said population surveys carried out every year, including in Otago rivers, had shown significant and alarming drops in numbers since about the mid-1990s. ''The New Zealand population of sea salmon in the last 10 years has been the lowest since they were introduced in the 1900s,'' Mr Hall said.

The UK will back a total ban on insect-harming pesticides in fields across Europe, the environment secretary, Michael Gove, has revealed. The decision reverses the government’s previous position and is justified by recent new evidence showing neonicotinoids have contaminated the whole landscape and cause damage to colonies of bees. It also follows the revelation that 75% of all flying insects have disappeared in Germany and probably much further afield, a discovery Gove said had shocked him.

Neonicotinoids are widely used insecticides, but their use is subject of debate because of their detrimental effects on pollinators. Little is known about the effect of neonicotinoids on other beneficial insects such as parasitoid wasps, which serve as natural enemies and are crucial for ecosystem functioning. Here we show that sublethal doses of the neonicotinoid imidacloprid impair sexual communication and host finding in the parasitoid wasp Nasonia vitripennis. Depending on the dose, treated females were less responsive to the male sex pheromone or unable to use it as a cue at all.

In this study, effects of two neonicotinoid insecticides, imidacloprid and dinotefuran, on aquatic insect assemblages were evaluated in experimental rice mesocosms. During the 5-month period of the rice-growing season, residual concentrations of imidacloprid were 5–10 times higher than those of dinotefuran in both soil and water. Imidacloprid treatment (10 kg/ha) reduced significantly the populations of, Crocothemis servilia mariannae and Lyriothemis pachygastra nymphs, whereas those of Orthetrum albistylum speciosum increased slightly throughout the experimental period.

7 years ago I spoke out in favor of a ban on neonicotinoids. These are cumulative poisons without thresholds that contaminate entire areas of the country and, moreover, are only slowly degraded. It's a nearly perfect script for insect extermination. This also means that if neonicotinoids are banned, insect decline will not cease immediately, as it will take years for these substances to be removed from the environment. Therefore, we do not have much time left to turn the page. Any hesitation now can lead to the complete collapse of the ecosystem.

A deadly amphibian disease called severe Perkinsea infections, or SPI, is the cause of many large-scale frog die-offs in the United States, according to a new study by the U.S. Geological Survey. Frogs and salamanders are currently among the most threatened groups of animals on the planet. The two most common frog diseases, chytridiomycosis and ranavirus infection , are linked to frog population declines worldwide. The new study suggests that that SPI is the third most common infectious disease of frogs.

In Pennsylvania, there are 21 native species of snakes, 14 species of turtles and four species of lizards. Here's a description of the four lizards that are native to Pennsylvania. The northern fence lizard (Sceloporus undulatus hyacinthinus) is part of a group commonly known as spiny lizards. It grows to 4-7 inches in length, and spends much of its time in the branches of trees. Insects, and sometimes snails, make up the diet of the northern fence lizard. The species is found in open woodlands across the southern two-thirds of Pennsylvania.

The lesser prairie-chicken (Tympanuchus pallidicinctus) belongs to the grouse family of birds so iconic to prairie culture. This brown-barred, stocky species nests in shrubbery and grasses of the Texas panhandle, Oklahoma, New Mexico, Kansas and Colorado. David Hunter, owner of Hunter’s Livestock Supply in Woodward, recollected that the prairie-chickens were often spotted on his family’s 120-year-old farm in eastern Woodward when he was young. “There were just thousands of them everywhere,” the 57-year-old told me.

Things aren’t looking good for wild pheasants in California, where populations of the colorful game birds have fallen to less than 10 percent of what they were in the late 1990s. With pheasant (Phasianus colchicus) hunting season opening Saturday, state officials note populations of the bird have fallen dramatically over the past 19 years. Hunters reported shooting 4,828 pheasant roosters in 1998 on public lands in the Central Valley. But that number fell to 461 last year, according to the California Department of Fish and Wildlife.

The determination of safe levels of exposure to potentially poisonous substances for humans and the environment is a fundamental goal of toxicology. Adverse effects result from interactions of the chemical with critical receptors in the organism, the extent of which depends on the exposure level but often on exposure time as well. Time-dependent toxicity occurs when the receptor binding is either slowly reversible or irreversible, and cumulative effects may also occur under such conditions. However, dose-time-response studies to demonstrate time-cumulative toxicity are rarely conducted.