Butterflies

One of the sure signs of spring — monarch butterflies (Danaus plexippus) — might be harder to find this year, scientists announced this week. The number of monarch butterflies at winter breeding grounds in Mexico is around 78 million , down from 100 million a year before. The figures illustrate the striking decline in the migrating butterflies' population in past two decades. Today, monarchs number less than one-tenth of their population in 1996, when scientists estimated a whopping 1 billion of the insects.

Butterflies have vanished from towns and cities more rapidly than from the countryside over the past two decades, according to a new study. Industrial agriculture has long been viewed as the scourge of butterflies and other insects but city life is worse – urban butterfly abundance fell by 69% compared to a 45% decline in rural areas over 20 years from 1995. Butterfly species such as the small copper and small heath have suffered particularly disastrous urban declines, according to the study published in the journal Ecological Indicators.

A survey of monarch butterflies overwintering in California shows that the population has not rebounded. Although the total number of monarchs counted this year was greater than last, the difference is due to a large increase in volunteer effort. Counts at major sites were down when compared to recent years. Volunteers with the Xerces Society’s Western Monarch Thanksgiving Count visited 253 sites and tallied a total of 298,464 monarchs—a fraction of the 1.2 million monarchs recorded in the late 1990s.

In the final weeks and months of the Obama administration, the Environmental Protection Agency’s Office of Pesticide Programs issued a flurry of reports on some of the country’s most widely used pesticides. Decisions made on the basis of these environmental and health assessments will likely determine the level of pesticide residue allowed on the food we eat. They will affect children’s neurological health and development, particularly in agricultural communities. They will determine how farmworkers are protected from pesticide exposures.

I colossi dell’agrochimica tornano all’assalto di Bruxelles per salvare i loro prodotti a base di neonicotinoidi. Nel 2013 l’Agenzia europea per la sicurezza alimentare (EFSA) aveva puntato il dito contro il thiamethoxam (prodotto da Syngenta), il clothianidin e l’imidacloprid (entrambi prodotti da Bayer) nel caso di applicazione spray sulle colture. L’Agenzia Ue con sede a Parma aveva poi concluso in uno studio del 2015 che «sono stati identificati gravi rischi o non è stato possibile escluderli».

Die zwischen Getreidehalmen schimmernden, blutroten Blüten des Klatschmohns sind vielen Menschen ein vertrauter Sommerbegleiter. Tatsächlich sind aber seine zarten Blüten auf Äckern gar nicht mehr so häufig zu sehen. Denn zusammen mit vielen anderen Ackerwildpflanzen verschwindet der Mohn allmählich aus einem Lebensraum, der flächenmäßig zu den wichtigsten Ökosystemen in Deutschland zählt. In den heute viel zu intensiv bewirtschafteten Äckern lebten ursprünglich rund 350 Pflanzenarten.

The last few years haven’t been good for the Oregon silverspot butterfly (Speyeria zerene hippolyta). Already a threatened species with just four populations on the Oregon Coast, the yellow-orange butterfly’s numbers plummeted even lower in recent years, biologists said. The silverspot declined from a population of thousands to as little as 120 on Mount Hebo, the species' largest population in Oregon, according to a report by the U.S. Fish and Wildlife Service.

Wenn Frank Baum aus Staufen in seinen Garten ging, fehlte es ihm an bunter Gesellschaft. Die Schmetterlinge machten sich rar. Den kleinen Fuchs oder das Tagpfauenauge suchte der Biochemiker vergeblich. Jetzt hat Baum sich zusammen mit anderen Naturschützern an die Landesregierung gewandt, um etwas gegen das Insektensterben zu unternehmen. Sie wollen erreichen, dass bestimmte Pflanzenschutzmittel dauerhaft verboten werden. Ansonsten befürchten sie einen Frühling ohne Schmetterlinge.