Dragonflies, info request

Objavljeno u Vaša pisma

Can anyone help with information about dragonflies on Hvar?

Dragonfly Dragonfly Steve Jones

Steve from Dol has sent us the following query by email on 23rd September 2016:

'Do you know much about dragonflies on the Island?

Over the Summer I have seen several and I know Norman nearby has also seen similar.

While I know a few of the more obvious ones I am puzzled, one thing I do know is that they like water in which to lay. The dragonfly life cycle is for the most part spent underwater and they only emerge as what we see towards the end of their life and to mate.

I am puzzled as to where they can possibly lay eggs, I only know one source of water down near the airfield and I don’t believe from there they would travel up to Dol. I often think they could be laying in the numerous wells/water storage places in the field but most are covered and I don’t know how they would emerge. One species described to me was the Golden Ringed Dragonfly and this as I read likes fast flowing water so I even more at a loss.

I was down near the airfield yesterday and several of just two species that I could tell were flying the one species tended to be flying joined to his mate, there were several of these

Didn’t know whether or not you can shed any light on this for me? I know of someone in the UK who specialises in Dragonflies, I may email him and see what comes of it.'

Eco Hvar's reply, 23rd September 2016:

Yes, actually there are many more sources of water than you'd think, off the beaten tracks, but also in the fields.

One of Hvar's 'secret' pools. Photo Vivian Grisogono

A lot of the enclosed wells have open basin on top,which can be home to all sorts of insects, including water snakes. Unless the fields around the wells have been doused in herbicide of course. There was a superb little water snake in the open part of the well by my field one year. It would curl itself round and round very lazily, right up to the time the basin went dry. I was afraid 'my' snake had died, lying there quietly, but it then discreetly disappeared, re-appearing a cuple of times in the grass above the well, presumably looking forward to the winter rains which would replenish its basking place. 

Talking about herbicide, did you see that the sale of Cidokor/Roundup is to be banned from October 1st, together with 12 other glyphosate-based herbicides? Good as far as it goes, but it still leaves 12 other glyphosate herbicides on the market!

We''ll look forward to hearing the results of your dragonfly investigations. A good place to see them is in the environs of Humac, where there are some lovely natural pools where the horses and some hunting dogs drink and butterflies abound, as there are no poisoned fields in the vicinity.

Nalazite se ovdje: Home vaša pisma Dragonflies, info request

Eco Environment News feeds

  • Analysis shows average levels are 30cm higher than thought, and up to 150cm in south-east Asia and Indo-Pacific

    Sea levels around the world have been underestimated due to inaccurate modelling, with research suggesting ocean levels are far higher than previously understood.

    The finding could significantly affect assessments of the future impacts of global heating and the effects on coastal settlements.

    Continue reading...

  • Government says it is working to solve ‘postcode lottery’ of access to green or blue spaces

    There are urban areas of England where no one lives within a 15-minute walk of nature, government data shows, as ministers scramble to meet their access to nature targets.

    While the data shows 80% of people live within walking distance of green or blue spaces such as a river, park or woodland, it also reveals a disparity between rural and poorer urban areas.

    Continue reading...

  • Olivier De Schutter says new economic agenda needed to tackle crises of rising inequality and ecological collapse

    The global economy must be reordered to ensure it serves ordinary people around the world rather than the “frivolous and destructive demands of the ultra-rich”, according to a leading UN figure.

    Olivier De Schutter, the UN special rapporteur on extreme poverty and human rights, says politicians must stop prioritising “socially and ecologically destructive growth” that only increases the profits – and serves the consumption demands – of the world’s richest individuals and corporations.

    Continue reading...

  • Puffins, guillemots, razorbills and terns are washing up on shores across Europe, after a string of storms affected their ability to find food

    The two puffins washed up among seaweed and bits of plastic on a beach in Newquay, Cornwall, on a damp February morning. Normally, these much-loved seabirds pull in crowds of tourists eager to see their courtship rituals, but these were rolling in the surf, dead. Most people walking past probably missed them.

    Their breast bones were sticking out, they had no fat on them, and their muscles were wasted; the pair probably starved to death, unable to find enough food out in the Atlantic Ocean where they spend the winter.

    Continue reading...

  • Aker QRILL is facing criticism of its fishery management amid calls by environmentalists for curbs on Antarctic fishing of the keystone species

    Environmental groups have objected to the recommendation of a “blue tick” sustainability label being awarded to a Norwegian krill fishing giant, amid concerns over concentrated fishing pressure and dramatic climate-driven effects on the Antarctic’s fragile ecosystem.

    Norway’s Aker QRILL, the world’s largest harvester of krill, a tiny crustacean and keystone of Antarctica’s fragile ecosystem, and its sister company, Aker BioMarine, produce feed additives for aquaculture and dietary supplements for pets and humans.

    Continue reading...

  • Scientists are calling loss of biodiversity the ‘homogenocene’, where niche species are pushed out by generalists like pigeons and rats

    Plants and animals are disappearing at an alarming rate across the planet, with some estimates suggesting a loss of up to 150 species every day. Meanwhile, the versatile species that thrive alongside humans, such as pigeons, rats and cockroaches, expand to fill the vacant gaps. Some scientists are calling this loss of biodiversity the “homogenocene”: the era when the world’s wildlife became more samey.

    It started during the last ice age, when humans hunted large mammals such as the mammoth to extinction, and has continued to the present day as land is cleared to make way for fields, farms and cities. Specialist creatures that exploit a particular niche – such as the flightless Fijian bar-winged rail – have been pushed out by adaptable generalists, like mongooses, brought to Fiji by humans in the 1800s. More recently the homogenocene has hit the oceans, with warmer waters devastating coral reefs for example.

    Continue reading...

  • Instead of removing plant-munching caterpillars, gardeners asked to take relaxed attitude to support the moths many of them grow into

    As spring unfolds and plants come to life, gardeners often fight a losing battle against the caterpillars who munch their cabbages.

    Traditionally, advice for gardeners regarding caterpillars would be about how to get rid of them and stop unsightly holes in plants. But the Royal Horticultural Society (RHS) and the Wildlife Trusts are asking Britons to take a relaxed attitude to caterpillar carnage in order to support the moths many of them grow into.

    Foxgloves:These pretty plants are food for several moths, including the lesser yellow underwing (Noctua comes), angle shades moth (Phlogophora meticulosa) and setaceous Hebrew character (Xestia c-nigrum).

    Lady’s bedstraw: This native wildflower with frothy yellow blooms provides food for the hummingbird hawk-moth (Macroglossum stellatarum), elephant hawk-moth (Deilephila elpenor) and bedstraw hawk-moth (Hyles gallii).

    Mullein:These tall, drought-resistant yellow plants are enjoyed by the brightly striped caterpillars of the mullein moth (Cucullia verbasci).

    Mint:This provides food for the mint moth and beautiful plume moth. It is also loved by bees.

    Hedges:If you have space, a mixed native hedge planted with hawthorn (Crataegus monogyna), blackthorn (Prunus spinosa), hazel (Coryllus avellana) and dog rose (Rosa canina) provides food for a multitude of caterpillars.

    Continue reading...

  • Shrinking and faster-moving glaciers, weakened ice shelves and more icebergs would bring fundamental changes

    You don’t need an umbrella in Antarctica. With an average of just 16cm of precipitation each year, this continent is the world’s largest desert. But all that could change. A study shows that as the world warms, Antarctica is going to experience more rain, bringing with it fundamental changes to the landscape and wildlife inhabiting this unique environment.

    Bethan Davies, a glaciologist at Newcastle University, has been leading a team studying the impact of a warming climate on the Antarctic peninsula. Under faster warming scenarios (2C or more this century) they report in Frontiers in Environmental Science that snow and rain could increase by more than 20%, with increasing amounts falling as rain.

    Continue reading...

  • The conflict in the Middle East has sent energy prices soaring, and for countries that import a high proportion of their fuel, it’s a reminder of the perils of energy dependence. As the recipient of almost 90% of Iran’s crude oil, China knows this only too well. Which partly explains why the country spent the last decade heavily investing in clean power.

    To find out what else could be driving the strategy, Madeleine Finlay speaks to senior China correspondent Amy Hawkins.

    And energy correspondent Jillian Ambrose reflects on how China’s ambitions could affect the rest of the world

    Support the Guardian: theguardian.com/sciencepod

    Continue reading...

  • At the council recycling tip in Chingford, people drop off fridges, dishwashers, mattresses, golf clubs, bicycles and batteries – then head into the shop to hunt through the weird and wonderful treasures

    When an embalmed rabbit in a Perspex box arrived at the dump in Chingford, north-east London, last year, with fur on its head but its organs and skeleton exposed to teach veterinary students about the digestive system, Lisa Charlton knew she had to save it from landfill. She was sure that one of her regulars, a man interested in anything “a bit weird, macabre and bizarre” would buy it. And he did.

    Charlton, who has worked at the recycling centre’s onsite ReUse shop for a year and a half, has salvaged items ranging from furniture, old toys and lampshades to walking frames brought in by local people. She has put aside some cast-iron cauldrons for her sister who is “into crystals and healing” and runs a shop in Cornwall. Items that have come through her shop include vintage crockery, antique crystal vases with solid silver rims, a spindly chair from the 1920s and an old ammunition box.

    Continue reading...

Novosti: Cybermed.hr

Novosti: Biologija.com

Izvor nije pronađen