Butterflies

This letter is in response to Julee Boan’s excellent article about Ontario’s Endangered Species Act (Paying the Interest, Ignoring the Debt — CJ, Nov. 29). This act is extremely important and we ignore it at our peril. In towns and cities we have animal humane societies that ensure that the animals under our care in our homes are given the best protection we can offer. The animals, fish and insects in our wilderness are no less deserving. The act should be their voice to protect them from the harmful impacts of mining, fossil-fuel extraction, forestry, fishing and farming, not for the protection of these same industries. These impacts are real and can be devastating. Two examples from farming have come to my attention lately. Both were preventable.

We counted butterflies on transect surveys during Hesperia ottoe flight period in 1988–2011 at tallgrass prairie preserves in four states (Illinois, Iowa, Minnesota, Wisconsin), divided into units cross-referenced to vegetation type and management history. H. ottoe occurred only in dry and sand prairie types, and was significantly more abundant in undegraded than semi-degraded prairie, and in discontinuous sod (with numerous unvegetated areas due to bare sand and/or rock outcrops) than in continuous sod. This skipper was significantly more abundant in small sites compared to medium and large sites, even when the analysis was limited to undegraded prairie analyzed separately by sod type. H. ottoe was significantly under-represented in year-burn 0 (the first growing season after fire) compared to an expected distribution proportional to survey effort. However, H. ottoe was also over-represented in fire-managed units compared to non-fire-managed units. However, by far most units and sites were in fire management and most populations declined to subdetection during this study.

Die intensive Landwirtschaft verantwortet einen dramatischen Artenrückgang. Nach einer Studie der Europäischen Umweltagentur, ist in den letzten 20 Jahren der Bestand an Wiesenschmetterlingen um rund 50 Prozent zurückgegangen. Landwirtschaftliche Monokulturen und starker Pestizideinsatz zerstören demnach Europaweit den Lebensraum der Schmetterlinge. „Wir brauchen eine Landwirtschaft, die Artenvielfalt in unsere Obst- und Weinanlagen, Äcker und Wiesen zurück bringt, und das ist das Ziel unserer Naturschutz-Beratung,“ sagt Bioland-Obmann Michael Oberhollenzer. „Die Biologische Bewirtschaftung der Betriebe ist der grundlegende Schritt, um die Südtiroler Natur zu schützen. Wir Bioland-Bauern gehen noch weiter, indem wir zusätzlich aktive Naturschutzmaßnahmen am Betrieb treffen.“ Von den rund 600 als gefährdet eingestuften Pflanzenarten Südtirols sind 41 Prozent durch die intensive Landwirtschaft gefährdet. Neben Pflanzen feuchter Standorte sind typische Wiesenarten von Standorten mit geringem bis mittlerem Nährstoffgehalt besonders betroffen.

A butterfly at risk from pesticides and a plant potentially targeted by collectors are B.C.'s newest endangered species, according to an annual assessment by the Committee on the Status of Endangered Wildlife in Canada (COSEWIC). The Oregon branded skipper (Hesperia colorado oregonia) inhabits sparsely vegetated at-risk Garry Oak and coastal sandspit ecosystems and is found in only four of 16 fragmented sites totalling less than 16 square kilometres. It is threatened by the application of Btk pesticide used to control the invasive gypsy moth and by the encroachment of vegetation in open habitats. Also endangered is Tweedy's Lewisia, a showy perennial plant that exists in two small sub-populations and has undergone a decline of up to 30 per cent in recent years.

De Europese Unie is op 1 december 2013 moedig begonnen met een verbod van twee jaar op bepaalde toepassingen van drie neonicotinoide pesticiden die schadelijk voor honingbijen en andere bestuivers zijn. Het Europese verbod gaat over neuroactieve insecticiden die in hun werking vergelijkbaar zijn met nicotine. De bekende gevolgen voor bijen variëren van negatieve beinvloeding van foerageergedrag en navigatie (die hun vermogen om gewassen te bestuiven vermindert) tot de dood. Bestuivers zijn essentieel voor onze voedselvoorziening en landbouweconomie. Ze zorgen voor meer dan een derde van het voedsel dat we eten, verbeteren de productie van 75 procent van alle soorten gewassen, en zijn essentieel voor talrijke gewassen, zoals amandelen, avocado's, appels en kersen. Maar we moeten veel meer doen, en uitgroeien tot een wereldleider in duurzame alternatieven voor schadelijke pesticiden.

On the first of November, when Mexicans celebrate a holiday called the Day of the Dead, some also celebrate the millions of monarch butterflies (Danaus plexippus) that, without fail, fly to the mountainous fir forests of central Mexico on that day. They are believed to be souls of the dead, returned. This year, for or the first time in memory, the monarch butterflies didn’t come, at least not on the Day of the Dead. They began to straggle in a week later than usual, in record-low numbers. Last year’s low of 60 million now seems great compared with the fewer than three million that have shown up so far this year. Some experts fear that the spectacular migration could be near collapse. “It does not look good,” said Lincoln P. Brower, a monarch expert at Sweet Briar College. It is only the latest bad news about the dramatic decline of insect populations. Another insect in serious trouble is the wild bee, which has thousands of species. Nicotine-based pesticides called neonicotinoids are implicated in their decline, but even if they were no longer used, experts say, bees, monarchs and many other species of insect would still be in serious trouble.

In ruil voor de miljarden euro's aan jaarlijks betaalde belastingen werd de Europeanen een groene en duurzame hervorming van het gemeenschappelijk landbouwbeleid (GLB) beloofd. Maar nu de besluiten zijn genomen is het zeer onwaarschijnlijk dat een groenere en duurzame landbouw vorm aan zal nemen. Vrijstelling van groene maatregelen is eerder regel dan uitzondering geworden. Erger nog, in sommige landen is deze zogenaamde "groene" hervorming eerder een stap achteruit door onevenredige bezuinigingen op het groene Fonds voor plattelandsontwikkeling en een reductie van de milieu-eisen.

In less than 20 years, neonicotinoids have become the most widely used class of insecticides with a global market share of more than 25%. For pollinators, this has transformed the agrochemical landscape. These chemicals mimic the acetylcholine neurotransmitter and are highly neurotoxic to insects. Their systemic mode of action inside plants means phloemic and xylemic transport that results in translocation to pollen and nectar. Their wide application, persistence in soil and water and potential for uptake by succeeding crops and wild plants make neonicotinoids bioavailable to pollinators at sublethal concentrations for most of the year. This results in the frequent presence of neonicotinoids in honeybee hives. At field realistic doses, neonicotinoids cause a wide range of adverse sublethal effects in honeybee and bumblebee colonies, affecting colony performance through impairment of foraging success, brood and larval development, memory and learning, damage to the central nervous system, susceptibility to diseases, hive hygiene etc. Neonicotinoids exhibit a toxicity that can be amplified by various other agrochemicals and they synergistically reinforce infectious agents such as Nosema ceranae which together can produce colony collapse. The limited available data suggest that they are likely to exhibit similar toxicity to virtually all other wild insect pollinators. The worldwide production of neonicotinoids is still increasing. Therefore a transition to pollinator-friendly alternatives to neonicotinoids is urgently needed for the sake of the sustainability of pollinator ecosystem services.

Butterflies in Singapore have decreased in both number and variety since the 1980s. Excluding new butterfly species, some 117 are now believed to be extinct; there have been no reliable observations of them for at least the past two decades. A comparison with past recorded checklists shows there are now 306 species, down from 386 in the 1950s to 1980s. Citing these figures, butterfly expert Khew Sin Khoon, who is also an honorary research affiliate at the Raffles Museum of Biodiversity Research, said the trend was mainly due to the loss of habitats. "Butterflies are tightly correlated with plants, and as Singapore developed, the habitats that they prefer may have been destroyed... Some of the caterpillar host plants may have (also) gone extinct," he said. It is not known when the sharpest decline in the number of butterfly species took place but Mr Khew said the peak of development occurred in the 1970s and 1980s when tracts of land were cleared to make way for new homes. Ecologist Anuj Jain, 29, said that over the years, developments around forests have resulted in what he calls "fragmented forests". "If the forest is big, you have a bigger interior but if you have smaller forests, it means there are more areas for light exposure," said Mr Anuj, who heads the Butterfly Interest Group at Nature Society of Singapore (NSS). "Although some species are adaptable to light conditions, most butterflies like to hide in darker areas."More recently, the increased fumigation in residential areas is also threatening butterflies and caterpillars, said Mr Khew.

An increasing body of scientific evidence indicates that many chemicals have biological effects at doses previously considered negligible. It is increasingly evident that more subtle deleterious effects can occur due to longer-term exposure to relatively low doses of chemicals, individually or in mixtures. New concerns have recently been raised about the impact of pesticides on non-target organisms including insects, especially bees, and amphibians. Studies suggest that low doses of neonicotinoids, a group of neurotoxic chemicals widely used in many countries as insecticides, could have sublethal effects on honey bees and bumble bees with serious consequences for wild populations of these crucially important pollinators and therefore for agriculture and the environment. It has also been suggested that detailed investigation of the effect of neonicotinoids on mammalian brain function, especially brain development, is needed to protect human health, especially that of children.