In Europe's temperate forests, less common plant species are being replaced by more widespread species. An international team of researchers led by the German Centre for Integrative Biodiversity Research (iDiv) and the Martin Luther University Halle-Wittenberg (MLU) has found that this development could be related to an increased nitrogen deposition. Their results have been published in the journal Nature Ecology & Evolution.
The number of insect species and insect abundances decreased severely during the past decades over major parts of Central Europe. Previous studies documented declines of species richness, abundances, shifts in species composition, and decreasing biomass of flying insects. In this study, we present a standardized approach to quantitatively and qualitatively assess insect diversity, biomass, and the abundance of taxa, in parallel.
Little is really known about the total numbers of insect species our planet holds and it is estimated that only between 10 and 20 per cent of insect and invertebrate species have been classified and named. We may well ask ourselves as to why the world’s insect population is declining with some species facing extinction?
Beekeepers around the world have been reporting the ongoing weakening of honeybee health and subsequently the increasing colony losses since 1990. However, it was not until the abrupt emergence of colony collapse disorder (CCD) in the 2000s that has raised the concern of losing this important perennial pollinator. In this report, we provide a summary of the sub-lethal effects of pesticides, in particular of neonicotinoids, on pollinators’ health from papers published in peer-review journals.
The yearly count of monarch butterflies overwintering in Mexico, released today, shows a decrease of 53% from last year's count and is well below the threshold at which government scientists predict the migration could collapse.
Scientists estimate that 6 hectares—about 15 acres—is the extinction threshold for the migratory butterflies' survival in North America. The latest count, conducted by World Wildlife Fund Mexico, found overwintering monarchs occupying just 2.83 hectares, or 7 acres.
La Selva is a swath of intact Costa Rican jungle protected from development specifically for use by science researchers and educators. Hints of research projects can be seen along the over 30 miles of pathways that weave through the jungle – a tree tagged with orange tape, a 3-square-foot plot of jungle marked off with string.
Solitary bees are frequently exposed to pesticides, which are considered as one of the main stress factors that may lead to population declines. A strong immune defence is vital for the fitness of bees. However, the immune system can be weakened by environmental factors that may render bees more vulnerable to parasites and pathogens.
The ruffed grouse (Bonasa umbellus) is a medium-sized grouse occurring in forests from the Appalachian Mountains across Canada to Alaska. The ruffed grouse is the state bird of Pennsylvania, United States. The ruffed grouse, a strikingly beautiful bird that symbolizes wildness, is in trouble across its native range.
Scientists have uncovered alarming declines in caterpillar diversity and their parasites across 22 years of monitoring in a protected forest in Costa Rica. Scientists studied the Lepidoptera order of moths and butterflies by collecting all externally feeding caterpillars — those found on leaves and not the inner tissue of a plant. They also collected the parasites that live off their caterpillar hosts, known as parasitoids, including wasps (order Hymenoptera) and flies (order Diptera).
Leonard et al. (1) presented an interesting approach to limit the impact of pathogens on honeybees by stimulating immunity via engineered symbionts. The urgency to safeguard pollinator services is undoubted. Massive declines in bees, insects in general, pose major concerns for ecosystem stability and food production. However, we see potential pitfalls in such technology driven approaches. Leonard et al. attribute high honeybee colony mortality to the parasitic mite Varroa destructor via synergistic interactions with RNA viruses. However, Varroa is only a significant concern for honeybees.