Vlinders

Pollinators are an essential part of a garden; so essential in fact, that 90 percent of the 250,000 flowering species now in existence rely on them according to the University of Georgia. Bees and butterflies make up the largest group of pollinators; however, the interior design of certain types of flowers makes it impossible for bees or butterflies to pollinate. These plants must rely on other types of insects to seek out the nectar they produce and pollinate them in the process.

Britain’s 30 million hedgehogs have been reduced to 1.3 million in the last 50 years. Three quarters of butterfly species are in decline. Britain has lost three of its 24 species of bumblebee in last 70 years. Moths numbers have dropped by a third since 1968. In the last 100 years, around 60 species of moth have become extinct. There are those who say all this angst about biodiversity is nonsense. But such free-marketers are wrong. Scottish Natural Heritage’s list of over 1,000 threatened species is not dominated by nice furry mammals or dramatic birds of prey, but by obscure lichens, algae, fungi, flowering plants, beetles, and more than 300 other insects on which the chaps at the top of the Mikado’s list depend, including us. “Therefore never send to know for whom the bell tolls; it tolls for thee.”

THE number of butterflies in Scotland hit an all-time low. Butterfly Conservation said the number of individual butterflies recorded was down 11% on the previous year and it warned of long-term decline in some species after the last four years have seen successive population falls. There are 59 species of butterfly, after four became extinct during the last century. The common blue butterfly was the worst affected this year, with its numbers tumbling by 61% in the UK-wide count, although it remains the seventh most common species in Scotland. The small tortoiseshell, which has declined in numbers in the rest of the UK, was the most common butterfly spotted north of the Border and three times as many of the species were recorded per count in Scotland than in England. The red admiral, ringlet and meadow brown are also faring relatively well north of the Border.

New Delhi: Red Pierrot, Common Lime, Plain Tiger, Blue Pansy or the Common Castor may be unfamiliar names to most Indians, although it is likely that most would have seen one or more of the five—the most common butterflies found in India. While it is unlikely that most people would notice their absence, it is almost certain that plants will—butterflies, such as these, help them reproduce. The subcontinent has approximately 1,300 of more than 20,000 butterfly species known, said Kishen Das, a US-based lepidopterist. That’s about 6.5% of the global butterfly diversity. However, the problem is that around 100 of the butterfly species found in India are nearing extinction, according to Surya Prakash, a professor at the department of life sciences at Jawaharlal Nehru University. “Few are aware of the crucial pollination role the butterfly plays, which is second only to the honeybee,” he adds.

To many people bugs are pests but in reality out of the millions of species worldwide only a tiny handful are actually true pests. The other, harsh, reality is that overall there definitely aren't as many species or numbers of bugs around as there were in the past. Why should that be important and why should we care - after all, insects are pests?

Well for one, many of the birds species we all know and love are declining because of either secondary pesticide poisoning or the lack of insect food available, especially at breeding time. Let's face it; every time we see a bug we don't want, we reach for the spray. Transfer that to an agricultural scale and you get mass extinction on the scale of the dinosaurs, but because many are tiny little inconspicuous creatures that we rarely see, we don't notice or care.

This is a fact: three of the 25 British species of bumblebees are already extinct and half of the remainder have shown serious declines, often up to 70%, since around the 1970s. In addition, around 75% of all butterfly species in the UK have been shown to be in decline. Insects of all sorts play a massive role in our lives and indeed our survival yet we disregard them so easily.

Nog steeds is de heivlinder Hipparchia semele een bekende verschijning op onze heidevelden en duinen. Maar toch is er de laatste jaren veel veranderd. Met een nieuwe techniek is de verspreiding van de heivlinder teruggerekend tot 1950. Weliswaar schommelt die verspreiding wat, pas vanaf 1990 zet een gestage achteruitgang in: de heivlinder verdwijnt van steeds meer plekken. De nieuwe techniek levert ook inzicht in de achterliggende oorzaken en de belangrijkste is versnippering: de heivlinder blijkt niet meer in staat te zijn om kleine plekken te herkoloniseren als hij verdwijnt. Alleen op grote aaneengesloten terreinen, zoals op de Veluwe, weet hij zich te handhaven. Uit de eerste resultaten van het Meetnet Dagvlinders lijkt 2011 een zeer slecht jaar te worden voor de heivlinder Hipparchia statilinus. Deze vlinder had het toch al erg moeilijk de afgelopen twintig jaar. De heivlinder is al sinds het begin van het Landelijk Meetnet Vlinders één van de zorgenkindjes. De aantallen zijn flink afgenomen. Waar je er in 1992 zo’n 100 telde, waren dat er in 2010 maar 16: een achteruitgang met 84%.