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Last month, a frog died in an Atlanta botanical garden. With it went an entire species never to hop along the Earth again. Biologists at Zoo Atlanta who’d looked after the frog for the past 12 years called him “Toughie.” He was a charismatic, glossy-eyed specimen and the very last Rabbs’ fringe-limbed tree frog in the world. Joseph Mendelson, the director of research at Zoo Atlanta, had been prepared for this. When the Rabbs’ frog was discovered in Panama in 2005, some 80 percent of the population had already been lost to disease. A few were removed in hope of a revival.

Forty years ago, swallows were a common sight in the summer, darting between the beams of old barns or swooping low over the waters of a creek. These swift aerial acrobats seemed to be everywhere -- perched on telephone lines by the dozen awaiting the fall migration, or whirling and diving around old wooden bridges in pursuit of airborne insects. Now, these birds have seemingly disappeared from midair, entirely abandoning large swathes of their former Canadian range. Some, like the bank swallow, have seen their numbers plummet by 98 per cent since 1970.

COMMON butterflies saw a collapse in their population numbers in Cumbria over the summer despite the UK experiencing weather conditions that usually help them to thrive. Results from the three-week Big Butterfly Count survey reveal a decline in the insect across the length and breadth of the country. The majority of butterfly species studied as part of the survey saw their populations fall with some producing their worst numbers since the Big Butterfly Count began.

This study measured part of the in-hive pesticide exposome by analyzing residues from live in-hive bees, stored pollen, and wax in migratory colonies over time and compared exposure to colony health. We summarized the pesticide burden using three different additive methods: (1) the hazard quotient (HQ), an estimate of pesticide exposure risk, (2) the total number of pesticide residues, and (3) the number of relevant residues. Despite being simplistic, these models attempt to summarize potential risk from multiple contaminations in real-world contexts.

This thesis by Sebastian Stehle analyses the agriculture–environment linkages for pesticides at the global scale and it thereby contributes to a new research frontier in global ecotoxicology. The overall findings substantiate that agricultural insecticides are potential key drivers for the global freshwater biodiversity crisis and that the current regulatory risk assessment approaches for highly toxic anthropogenic chemicals fail to protect the global environment.

The evaluation of pesticide side-effects on honeybees is hampered by a lack of colony-level bioassays that not only are sensitive to physiological changes, but also allow predictions about the consequences of exposure for longer-term colony productivity and survival. Here we measured 28 biometrical, biochemical and behavioural indicators in a field study with 63 colonies and 3 apiaries. Colonies were stressed in early summer by feeding them for five days with either the carbamate growth regulator fenoxycarb or the neurotoxic neonicotinoid imidacloprid, or left untreated.

With a crown of stiff gold-coloured feathers on its head, a bright red gular sac and body made of gray, brown, gold and white patches, the grey crowned crane stands out for its striking features. Commonly called the crested crane (Balearica regulorum), it is a bird of national significance to Uganda, occupying a prime position on the country's national flag and coat of arms. Yet despite its serenity, beauty and popularity, the crested crane is facing the threat of extinction.

High brown Fritillary butterfly - Once widespread it is now reduced to around 50 sites and threatened with extinction; Great Crested Newt – a sharp decline with only around 75,000 existing across the country; Hen Harrier – One of Britain’s most threatened birds of prey with only around 600 breeding pairs left; Hazel Dormouse – declined by one third in recent years and it is not extinct in 17 counties; Barbastelle Bat – widespread decline and fewer than 5,000 remaining; Ringed plover – only 5,600 breeding pairs remaining; Water vole – populations have dropped by 90 per cent in recent years;

Paris is full of sparrows. It always has been, and the city’s most memorable singer, small but irrepressible, called herself after the French slang word for sparrow, piaf. But London isn’t. Not any more. In one of the most remarkable events in the natural world of the last few decades, only now being properly perceived, the capital’s sparrows have disappeared.