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

Novosti: Ekologija.hr

  • Hundred-and-fifty-year-old Wych elm in Newcastle, Co Down has grown sideways owing to strong winds

    The “astonishing and bizarre” Bendy Tree in Northern Ireland has been crowned the winner of this year’s tree of the year competition.

    The wych elm tree, located in Newcastle, County Down, owes its name to its near horizontal trunk, which has grown sideways owing to the strong seaside winds coming off the Irish Sea.

    Continue reading...

  • The Norwegian government has given a permit to a mining company to release waste into Førde fjord despite a 17-year battle by campaigners and a supreme court ruling against it

    Shortly after the Norwegian stock market closed on 17 June 2026, a few dozen local people from the small west coast town of Vevring crowded around a laptop in a school. Surrounded by children’s drawings and windows looking out over Førde fjord, they listened as news arrived from Oslo. Norway’s supreme court had ruled against its government: a permit to release mining waste directly into the fjord two miles upstream was illegal, the court said.

    The moment marked the end of a 17-year fight, one of Norway’s most protracted environmental battles in living memory. In Oslo, Ingvild Fonn Asmervik, the project leader for Naturvernforbundet (Friends of the Earth Norway), compared the joy she felt to giving birth to her child. For Anne-Line Thingnes Førsund, a third-generation fisher living on the banks of the fjord in Vevring and a volunteer for the charity’s local branch, it was more of a relief. Like a mountain lifting off her shoulders, she said.

    Continue reading...

  • The UK state is dumping its responsibilities on our doorsteps, while green-lighting policies that lead us closer to crisis

    Would you mind fixing the NHS? And while you’re at it, could you please build an anti-missile system in your garden? Then regulate the banks, replace the water mains, tax the very rich and use the proceeds to rebuild our schools. Well, come on people: what are you waiting for?

    I exaggerate, but this isn’t very far from the approach taken by the government’s Prepare campaign. Crucial functions, way beyond the scope of individual action, are dumped on our doorsteps while those in power fail to act. As a result, our national resilience is arguably lower than at any time since the second world war. At the Labour conference last week, Andy Burnham promised “a Britain where people feel the country has got their back again”. To make good on that pledge, he will have to change almost everything.

    George Monbiot is a Guardian columnist

    Continue reading...

  • Linkenholt, Hampshire and Wexcombe, Wiltshire:Even to the untrained eye, traditional ones and modern, regenerative ones look very different

    Stubble fields, those post-harvest acres of short straws, seem to be lasting longer into the season, as farmers respond to changing practices. I have a wistful attachment to stubble fields: for so long a kind of temporary commons where, for a few redundant weeks before autumn or winter ploughing, you could shortcut across them, the dew-filled straws flicking water up the inside of your legs. But today, stubble fields aren’t all equal.

    Below Cleve Hill Down, a tractor is drilling winter wheat directly into bare seedbed between the stubble. Regularly sprayed with herbicide, it is free of weeds or any green – a pale-gold spread of machine-knitted tweed. A hundred years ago, the stubble would be left, full of weeds, birds and insects, until midwinter ploughing, allowing frosts to break down the clods.

    Continue reading...

  • A landmark report reveals that the world must change the way it produces food to avoid a biodiversity collapse

    Conservation comebacks for wild tigers, tuna and green​ sea turtles prove that global nature loss can be reversed, ​scientists have said. ​But a report warns food production must be the next ​“positive tipping point​” if the world is to avert biodiversity collapse.

    The World Wildlife Fund (WWF) analysed nearly 36,000 animal populations and more than 5,000 species, producing the largest ever database of vertebrate wildlife. Scientists found populations had declined by an average of 73% since 1970, showing that “nature continues to be degraded at an alarming scale”, with “no sign of losses slowing”.

    Continue reading...

  • Chinstrap penguins on Zavodovski Island in Antarctica down by two-thirds since 2011, probably due to climate crisis

    The world’s largest penguin colony has declined by two-thirds since 2011, most likely because of the climate crisis, a study has revealed.

    Scientists said the rapid demise of chinstrap penguins on Zavodovski, the northernmost of the South Sandwich Islands in Antarctica, increased the risk of a wider ecosystem collapse.

    Continue reading...

  • Guardian reporters Jonathan Watts and Gabrielle Canonanswered your question climate and extreme weather, from what to expect this winter in the UK to the increasing risk of natural disasters

    funkymentalist asks: Unrelated to El Niño, what is the likelihood of the AMOC (Atlantic meridional overturning circulation) shutting down?

    Jon says: I don’t think these two things are unrelated. Everything is affected by climate breakdown. And both El Niño and the slowdown of AMOC are related to the staggeringly huge amounts (see this article on zettajoules which I also referred to above) of extra energy that the oceans are being forced to absorb as a result of greenhouse gas burning.

    Quick refresher for any readers who are unfamiliar with this topic: “Amoc, or the Atlantic meridional overturning circulation, is a system of ocean currents that brings heat into the northern Atlantic. Warm surface water from the tropics flows north and releases its heat in the subpolar Atlantic, south of Greenland and west of Britain and Ireland. Then it cools and sinks to a depth of between 2,000m to 3,000 metres before returning south as a cold current. Amoc is one of our planet’s largest heat transport systems, moving the equivalent of 50 times the human energy use, and it has a particularly strong impact on the climate in Europe, affects the ocean’s CO2 uptake and oxygen supply, as well as rainfall patterns in the tropics.”

    Gaby says: The name “El Niño” actually harkens back to long before forecasters used the phenomenon to track global weather patterns. Fishermen off the coast of South America began to track unusually warm water that would show up every few years right around Christmas - thus “The Little Boy” referring to the Christ child in Spanish. Scientists adopted the name, and added “La Niña” as its counterpart (when sea surface temperatures cool), and together they became ENSO - the El Niño Southern Oscillation. This year, though, feel free to call it “El Monstruo Gordo!” It’s going to be a big one.

    Continue reading...

  • Inquest under way into why President Lula’s success in curbing Amazon deforestation has not led to success at polls

    More fire, more ash, more crime, more death. And a globally important ecosystem driven ever more rapidly towards a point of no return. That is the prospect for the Amazon rainforest for at least the next four years if Flávio Bolsonaro holds on to the lead he established this week in the first round of Brazil’s presidential election.

    This appears to be of far more concern to the outside world than to voters in Latin America’s biggest, richest and most biodiverse nation.

    Continue reading...

  • A mix of natural disasters could all befall the state at once as it finds itself in the crosshairs of the climate phenomenon

    On a cloudless autumn afternoon, sunlight sparkled on the water that had quietly swallowed a busy intersection to the north of San Francisco, as the surrounding rush-hour traffic slowed to a painful crawl.

    There were no crashing waves or storm surges to blame for the flood. Marin county was one of many areas up and down the California coast affected by high tides last week, as parts of the Pacific swelled with excess warmth.

    Continue reading...

  • Wendy Wales and Tony Lonergan’s four-year fight over MACH Energy’s Mount Pleasant coalmine went all the way to the high court

    When Wendy Wales and Tony Lonergan and a few of their neighbours in the New South Wales Hunter region decided to take on the expansion of a local coalmine, people thought they were “crazy” to engage in the David and Goliath battle.

    “When we started this, people thought we were crazy – a little community group taking on a billion-dollar coal company, arguing that the climate harm from burning this coal is our problem too,” Wales says.

    Sign up to get climate and environment editor Adam Morton’s Clear Air column as a free newsletter

    Continue reading...

Novosti: Cybermed.hr

Novosti: Biologija.com