Algemeen

Fast 80 der rund 200 in der Schweiz brütenden Vogelarten laufen Gefahr, aus der Schweiz zu verschwinden

Für gefährdete Vogelarten haben sich die Lebensbedingungen in der Schweiz in den letzten 20 Jahren mehrheitlich verschlechtert. Dies zeigt der Swiss Bird Index (SBI), den die Schweizerische Vogelwarte Sempach erstellt hat. Fast 80 der rund 200 in der Schweiz brütenden Vogelarten sind auf der Roten Liste. Sie laufen damit Gefahr, aus der Schweiz zu verschwinden. Der SBI, den die Vogelwarte für diese gefährdeten Arten erstellt hat, zeigt, dass sich die Situation seit der erstmaligen Erhebung 1990 nicht verbessert hat.

1,300 Bird Species Are Threatened With Extinction

Conservationists are alarmed by the increasing number of birds under threat due to the damage being done to the earth's ecosystems. The most recent assessment for the International Union for Conservation of Nature Red List for endangered birds revealed that no less than 1,300 species are threatened with extinction. It means that if nothing is done, more than 1,000 species could disappear; disturbing and damaging the natural environment.

Immunsuppression durch neonikotinoide Insektizide an der Wurzel des globalen Rückgangs bei Wildtieren

Bereits in seinem Buch "Ende der Artenvielfalt – Neuartige Pestizide töten Insekten und Vögel“ warnt der niederländische Toxikologe Henk Tennekes vor den Gefahren von systemischen Neonicotinoid-Insektiziden. Damit untermauert er Ergebnisse verschiedener Studien aus den vergangenen Jahren: Neonicotinoide sind in jeglicher Konzentration wirksam, sofern die Dauer des Kontakts ausreichend lang ist. Selbst kleinste Mengen können auf lange Sicht verheerende Auswirkungen haben. Diese Stoffe (Handelsnamen sind Imidacloprid, Thiamethoxam oder Clothianidin) wirken nämlich auf das zentrale Nervensystem von Insekten und Wirbellosen und blockieren dort wichtige Funktionen. Die seit 1991 zunehmend eingesetzten Giftstoffe gelangen ins Grundwasser und verbleiben auch im Boden, wo sie schwer abbaubar sind. Wasser- und landlebende Tiere sind ihnen folglich permanent ausgesetzt. Wirken die Nervengifte in niedriger Dosierung zur Zeit der Anwendung nicht unmittelbar tödlich, haben sie dennoch langfristig eine zerstörerische Wirkung.Die Folgen dieser chronischen Toxizität sind Schäden an zahlreichen Arten wie Wassertiere, Regenwürmer, Käfer, Spinnen oder Schnecken. Und natürlich Bienen und anderen Insekten. Außerdem schwächen Neonicotinoide das Immunsystem der Tiere. Über dieses Phänomen berichtet Tennekes gemeinsam mit Forschern aus England und Australien in einer aktuellen Studie. Während bei Bienen und Fischen eine Schwächung des Immunsystems (Immunsuppression) durch Insektizide inzwischen nachgewiesen wurde, häufen sich die Indizien dafür, dass die Gifte auch für Infektionskrankheiten von Amphibien, Fledermäusen und insektenfressenden Vögeln verantwortlich sind. Solche Epidemien treten offensichtlich genau dort auf, wo in den Jahren zuvor große Mengen an systemischen Insektiziden eingesetzt wurden. Danach breiten sich die Krankheiten auch auf andere Regionen aus. Als Weckruf liefert die Studie nun Daten über die schleichende und heimtückische Gefahr, die von systemischen Insektiziden ausgehen. Und fordert zum Schutz der Land- und Wasserökosysteme ein Verbot der Neonicotinoide. Zumindest sollten die Gesamtauswirkungen aus einem neuen Blickwinkel untersucht und Langzeitfolgen zukünftig in Zulassungsverfahren integriert werden. Denn neonicotinoide Insektizide können auch bei Säugetieren - also uns Menschen - das Immunsystem beeinträchtigen.

Bijna 21.000 dieren en planten met uitsterving bedreigd

Wereldwijd worden er 20.934 soorten planten en dieren met uitsterving bedreigd, zo blijkt uit de nieuwe Rode Lijst van bedreigde soorten die IUCN (International Union for Conservation of Nature) vandaag presenteert. Dit zijn er 1.117 meer dan bij de vorige taxatie in de zomer van 2012. In totaal bracht IUCN de status van 70.294 plant- en diersoorten in kaart. Hiervan zijn er 799 uitgestorven en komen er 61 niet meer in het wild voor. Drie soorten zijn sinds de vorige editie uitgestorven: een tandkarper (Cyprinodon arcuatus), een hagedis (Chioninia coctei) en een zoetwatergarnaal (Macrobrachium leptodactylus).

Pesticiden kunnen de ongewervelden uitroeien

Uit twee onafhankelijke studies in de vakbladen Proceedings of the National Academy of Sciences en The Journal of Applied Ecology blijkt dat diverse water- en bodeminsectensoorten verdwijnen door hoge – maar legale – pesticidenconcentraties in hun leefgebieden. De onderzoekers van de eerste studie vergeleken riviertjes die sterk met pesticiden waren vervuild met zuivere waterbiotopen: 23 in Duitsland, 16 in Frankrijk en 24 in Australië. In Europa bleek sterk gecontamineerd water 42 procent minder insectensoorten te bevatten dan schone rivieren. In Australië bevatten de stromen met de hoogste pesticidenconcentraties 27 procent minder soorten dan de niet-vervuilde. De onderzoekers vonden ook dat de daling in biodiversiteit vooral te wijten is aan het verdwijnen van bepaalde groepen die gevoelig zijn voor pesticiden, zoals libellen, steen- en eendagsvliegen. Het zijn belangrijke schakels in de voedselketen van vissen en vogels.

Globally, one in eight bird species are considered at threat of extinction

The world’s birds are literally the canaries in the coal mine and their ongoing decline should serve as a warning signal of a global environment in peril, says an international report on the state of the world’s birds. Globally, one in eight species — 1,313 — are considered at threat of extinction, said the report by U.K.-based BirdLife International. Of these, 200 are considered on the brink. Nature is a crucial part of Earth’s life support system, said Leon Bennun, the group’s director of science, policy and information, and the numbers don’t bode well. “Birds are a great window into nature. They’re a wonderful indicator of the wider environment,” Bennun said. “Our assessment, unfortunately, shows us that birds are in decline, an indicator that nature itself is not in good shape.”

Report sullo stato della natura nel Regno Unito

Per la prima volta, 25 organizzazioni ambientaliste britanniche si sono riunite per la realizzazione di uno studio sullo stato della natura nel Regno Unito e nei Territori d'Oltremare. I risultati di quest'iniziativa sono stati raccolti e pubblicati in un report dal titolo "The State of Nature". Il report è il primo del suo genere a documentare lo stato e le tendenze delle popolazioni di animali e piante nel Regno Unito e nei suoi Territori d'Oltremare. Il report esamina lo stato della natura negli otto principali tipi di habitat del Regno Unito e propone una panoramica delle principali cause dei cambiamenti nella fauna.

An absence of positive political debate about the natural world is even more troubling than the decline in UK wildlife revealed by State of Nature report

More than half the wildlife species found in our islands are declining, under an assault of development, air pollution and chemical attack. Bumblebees, wildflowers, songbirds and butterflies are among the more obvious casualties. Perhaps even more troubling than freefall declines in red squirrels, harbour seals, hedgehogs, starlings and all the others, is the fact that the crisis facing the living fabric of our environment is hardly mentioned in politics. And not only have ministers recently turned their attention away from the protection of nature, they have presented efforts to protect it as the enemy of growth, development and business. George Osborne's claim that laws to protect rare species are a 'ridiculous burden on business', Owen Paterson's championing the cause of Bayer and Syngenta in opposing the moratorium on the use of neonicotinoid pesticides and Michael Gove's attempts to downgrade education about our relationship with the natural environment are recent cases in point. With this in mind we can confidently guess that the government's on-going review of EU environmental laws is not intended to strengthen the protection of nature in these islands.

A great reckoning awaits humanity if we fail to awaken from our delusions

The plight of the bees serves as a warning that we still may not quite understand ecology. Ecological farming is part of a larger paradigm shift in human awareness. The corporate denialists appear just like the Pope's shrouded inquisitors in 1615, who refused to look through Galileo's telescope to see the moons of Jupiter. Today's denialists refuse to recognise that Earth's systems operate within real limits. However, the state religion in this case is money, and the state religion won't allow it. The denialists cling to the presumed right to consume, hoard, and obliterate Earth's great bounty for private profits. But hoards of money won't reverse extinction, restore lost soils, or heal the world's bee colonies. Earth's delicately balanced systems can reach tipping points and collapse. Bees, for example, work within a limited range of marginal returns on the energy they exert to collect nutrition for their colonies. When winter bee deaths grow from 10% to 50%, the remaining bees are weakened by toxins, and the wild habitats shrink, that thin, ecological margin of energy return can be squeezed to zero. Surviving bees expend more energy than they return in honey. More bees die, fewer reach maturity, and entire colonies collapse. This crisis is a lesson in fundamental ecology. Rachel Carson warned of these systemic constraints 50 years ago. Ecologists and environmentalists have warned of limits ever since. Bee colony collapse now joins global warming, forest destruction, and species extinctions among our most urgent ecological emergencies. Saving the world's bees appears as one more necessary link in restoring Earth to ecological balance.

The current use of neonicotinoids threatens a range of ecosystem services

Neonicotinoids are now the most widely used insecticides in the world. They act systemically, travelling through plant tissues and protecting all parts of the crop, and are widely applied as seed dressings. As neurotoxins with high toxicity to most arthropods, they provide effective pest control and have numerous uses in arable farming and horticulture. However, the prophylactic use of broad-spectrum pesticides goes against the long-established principles of integrated pest management (IPM), leading to environmental concerns. It has recently emerged that neonicotinoids can persist and accumulate in soils. They are water soluble and prone to leaching into waterways. Being systemic, they are found in nectar and pollen of treated crops. Reported levels in soils, waterways, field margin plants and floral resources overlap substantially with concentrations that are sufficient to control pests in crops, and commonly exceed the LC50 (the concentration which kills 50% of individuals) for beneficial organisms. Concentrations in nectar and pollen in crops are sufficient to impact substantially on colony reproduction in bumblebees..Although vertebrates are less susceptible than arthropods, consumption of small numbers of dressed seeds offers a route to direct mortality in birds and mammals. Major knowledge gaps remain, but current use of neonicotinoids is likely to be impacting on a broad range of non-target taxa including pollinators and soil and aquatic invertebrates and hence threatens a range of ecosystem services.