Other insects

Zahl der von Insekten lebenden Vögel sinkt

Ob Bachstelze (Motacilla alba), Wiesenpieper (Anthus pratensis) oder Rauchschwalbe (Hirundo rustica): Die Zahl der von Insekten lebenden Vögel ist in den vergangenen 25 Jahren europaweit deutlich zurückgegangen. Laut einer im Fachjournal Conservation Biology veröffentlichten Studie sank sie durchschnittlich um 13 Prozent. Rund die Hälfte aller Vogelarten in Europa ernährt sich von Insekten. Noch erschreckendere Zahlen hatte vor zwei Monaten die Naturschutzorganisation Nabu (Naturschutzbund Deutschland) unter Verweis auf eine Zählung des European Bird Census Council genannt.

Iconic mayfly populations have declined by as much as 84 percent

The emergence of Hexagenia limbata mayflies, throughout the Great Lakes and parts of the mid-Atlantic region, is nearly a religious event in angling circles. Each year in early June, these enormous mayflies blanket the landscape, emerging by the billions each night, smothering waterways, riverbanks, roadways and more with thousands of tons of trout-candy biomass. Not long ago, these historic and essential emergences were almost wiped out. By 1970, Hexagenia were gone from large swaths of the Midwest.

Bayer attempts to discredit peer-reviewed study showing its products caused a Japan fishery to collapse

The May 2019 newsletter of the Saitama Ecosystem Conservation Society describes how, before the introduction of neonicotinoids in the 1990s, numberless brilliant red akiakane or autumn darter dragonflies could be seen around rice fields in the fall. Experiments by Japanese dragonfly expert Tetsuyuki Ueda of Ishikawa Prefectural University showed how the pesticides reduced the number of surviving dragonfly nymphs to a small fraction, and that the chemicals persist for years in the soil of rice paddy fields.

Rosemary A. Mason: The sixth mass extinction and chemicals in the environment: our environmental deficit is now beyond nature’s ability to regenerate

Two papers about the future of the planet appeared within a month of each other (June/July 2015): "Accelerated modern human-induced species losses: Entering the sixth mass extinction" was the first. The 6 authors calculated the average rate of vertebrate losses over the last century and compared it with the background rate of losses. They estimated it to be up to 114 times the background rate and asserted that this rate of losses of biodiversity indicated that a sixth mass extinction is already under way.

Capercaillie broods in pristine boreal forest in northwestern Russia: the importance of insects and cover in habitat selection

Capercaillie (Tetrao urogallus L., 1758), the largest and most size-dimorphic species of grouse, is decreasing in number throughout its man-modified range in the boreal forests of the Palaearctic. Poor reproduction owing to direct and indirect effects of commercial forestry is considered a main cause of the decline. We studied brood habitats in a pristine forest in northwestern Russia to identify key elements in habitat selection in the natural environment of this species.

Dramatischer Rückgang der Auerhuhnpopulation im Schwarzwald

Das Auerhuhn (Tetrao urogallus) gilt als Indikator artenreicher, lichter, von Nadelbäumen dominierter Wälder und besiedelt weltweit noch ein großes Areal. In West- und Mitteleuropa sind allerdings viele Verbreitungsgebiete isoliert und meist auf (Mittel-) Gebirgszüge begrenzt, viele Populationen sind bereits verschwunden oder stark zurückgegangen. Im Schwarzwald, Südwest-Deutschland, wurde die Auerhuhn-Population erstmals 1971 mittels flächendeckender Balzplatzzählungen geschätzt. Seit 1983 wurden diese Zählungen jährlich durchgeführt und dokumentiert.

Systemic pesticide concerns extend beyond the bees

In the summer of 2010, Henk Tennekes from Experimental Toxicology Services Nederland at Zutphen warned that the accumulation of neonicotinoids in the environment would not only decimate useful insects but also have a knock-on effect on other species, including birds (Curr. Biol. (2011) 21, R137–R139). At the time, Tennekes did not find much support for his views and went on to publish his warnings as a book — The Systemic Insecticides: A Disaster in the Making.

Not all smiles on annual bird count in Starved Rock State Park

Steve Gillam, Starved Rock volunteer Tom Williams and Starved Rock State Park natural resource coordinator Lisa Sons exchanged jokes and friendly chitchat as they trudged over a muddy path along a field edge, wetland and woods at Matthiessen State Park. They were not seeing many birds, despite sunny, breezy conditions and diverse habitat, during their after-lunch hike over their territory in the Starved Rock Audubon Society Christmas bird count. And they said they had not seen many birds in the morning among the oak trees and canyons in the Matthiessen Dells area.

Mayfly numbers drop by half since 2012

Mayflies, which form swarms in the billions that are visible on weather radar, are in steep decline, mirroring the plight of insects worldwide. Every summer, mayflies burst forth from lakes and rivers, taking to the skies of North America. These insects, which are particularly abundant in the northern Mississippi River Basin and Great Lakes, live in the water as nymphs before transforming into flying adults. They synchronize their emergence to form huge swarms of up to 80 billion individuals—so massive that, in waterside towns, they are sometimes scooped up with snowplows.

Das Insektensterben ist global

Das Verhältnis von Insekten und Landwirtschaft ist ein durchaus ambivalentes. Auf der einen Seite sind sie als Schädlinge für Ernteausfälle verantwortlich. Vor allem in den tropischen Ländern können sie bis zu 40 Prozent der Ernten vernichten. Sie werden deswegen von der Agrarwirtschaft intensiv bekämpft: Weltweit hat sich der Verbrauch von Pestiziden seit 1950 um das 50fache erhöht. Auf der anderen Seite ist Landwirtschaft ohne Insekten kaum denkbar. Sie sind unerlässlich für die Bodenqualität, indem sie Dung und abgestorbenes Material zersetzen.