Thursday 2 May 2013

Beefly (Bombylius major)


Beefly (Bombylius major), originally uploaded by Pipsissiwa.

Very excited today! I've been taking spring photos for a week or so now, but there has been very little worth blogging about. However today the garden had a visitor that I have always wanted to see - a beefly!

 

These insects look like mini (1cm ish) ginger pompoms with dark-edged wings and a long nose. They can appear fearsome but are completely harmless - the proboscis is solely for probing deep into flowers to drink nectar - the fly does not bite or sting,


They fly around low looking for ground dwelling bee nests in which to lay their eggs.

Tuesday 28 June 2011

Here Be Dragons!

On a horribly windy day last week I nevertheless ventured stoically into the garden to get some photos. Not much was happening and I was ready to go back in empty camera'd when I noticed something odd on a reed poking out of the pond.

To my great delight it was a dragonfly larval case. After spotting the skin, I looked around and suddenly spotted another one with an new adult resting above it on the plants nearby.

As with the damselflies I described in an earlier post, the dragonfly spends a large part of its life as an aquatic nymph.



When ready to emerge the larva climbs up a plant stem and then the skin cracks open, allowing the enclosed winged adult to crawl out. Over the next few hours the new adult dries out, hardens up and generally takes on the familiar form.

Still drying and stiffening its wings when I found it, it couldn't fly too well, although it did land on my hand at one point before it finally flew away :)

Whilst it is still very pale and only the black markings are really visible, I am sure it is a Common Darter (Sympetrum striolatum):

The size, black markings and the small fact that I watched these Common Darters mating & laying their eggs in the pond last August all strongly suggest the ID.

The reason why dragonflies have such a bulky thorax is almost entirely down to the huge and powerful flight muscles that power the wings. Although held along the abdomen when the insect first emerges, once dry and expanded, the wings are held permanently out to the sides; dragonflies are unable to fold their wings, even at rest. This is a key identification point between Damselflies (who hold their wings along their abdomen) and Dragonflies (who hold them out to the sides). These huge muscles allow Dragonflies to be incredibly fast and maneuverable in flight, more so than any other insect.

The huge compound eyes are quite incredible up close.

The wings themselves are made of a spectacular network of veins.

I haven't been lucky enough to see another emerging, but the reeds have loads of new skins on them every day, so I know they are there. :)

With luck they will be back looking for mates and lay their eggs in the pond for the next generation.

Wednesday 22 June 2011

The Pond - 14th June 2011

The Pond - 2011 - 11, originally uploaded by Pipsissiwa.

Its all go in the pond at the moment. The water forget-me-not is adding a lovely haze of tiny blue flowers that the bees and hoverflies are loving.

The reeds are covered in beautiful, wispy wind-pollinated flower tufts and provide a welcome resting place for the huge numbers of damselflies still mating and laying eggs. They also act as an essential stepladder, allowing damselfly and dragonfly nymphs to climb up out of the water and hatch into adults. That's why ponds without plants are useless for those insects to breed in.

Newly emerged damselflies and dragonflies are pale, vulnerable and unable to fly. Over the first few hours after emerging they cling to the plant stem and gradually stiffen their wings and develop their final adult colour.

Damselfly:

You can see the nymph 'shell' that these two newly emerged damselflies climbed out of. It amazes me that such a large insect can come from such a comparatively small nymph.

The left-hand picture shows a damselfly that had emerged only a few minutes before I managed to get the photo. It is squashed and pale, and the wings are longer than the thick and stumpy abdomen.

The right hand picture shows another damselfly when it was around an hour old, and you can see that the body is becoming much more long and slender, the wings are straightening and stiffening, and some colour is appearing along the abdomen and in stripes on the thorax.

Another hour or so and the insect looks much as the one below. It is becoming even more obviously marked and the distinctive shape of a damselfly is fully formed. The wings are only crumpled at the tips now.

Below is the same insect about an hour later still. The black markings are clear and well defined now, and the pale areas are starting to become noticeably blue.

Eventually, it will look as magnificent (and blue) as this fully mature adult.

Dragonfly:

This beautiful Common Darter Dragonfly is the latest insect from order Odonata that has passed through its nymph stage in the pond. I watched a pair of adults mating and laying eggs in August last year, amazingly only 2 weeks after the pond was created. The eggs obviously survived to grow into this magnificent adult and many more based on empty nymph cases left on the reeds. The left hand picture is of a nymph shell, distinctly different from a damselfly nymph as the body is much shorter and wider (you can see the difference clearly in the photo included in my previous post). The right hand picture above shows a new adult with the empty nymph shell below it sill clinging to the plant stem. A separate post on this individual with super close-up pics coming soon!


In the water, the Great Water Snails are mating like crazy and there are snail eggs all over the place.

The Water Boatmen (aka Backswimmers) are getting big and aggressive. They are carnivorous bugs (Heteroptera) with sucking mouth-parts, and will eat almost anything, even including young tadpoles and tiny fish. You can clearly see how they get their two common names from the photograph below. Swimming upside down primarily at the surface of the water (although they dive when alarmed), they use their extra long back legs like oars to propel themselves through the water. As air breathers they carry a bubble of water to breathe through, which can make their underside appear silvery.



The last few delicate mayflies are struggling from their nymph skins at the surface of the water, and most are managing to fly free and mate rather than getting caught on the surface tension and becoming dinner for other water life.


The frogs are now adults, and I see them every day enjoying the cover of the duckweed and frogbit, basking in the sun-warmed water or on the partially submerged logs.

The best visitor recently was a huge female Broad-Bodied Chaser Dragonfly, who popped by for a few minutes to lay her eggs. I heard her before I saw her, because her wings made a very deep and loud buzzing noise that is distinctive to large dragonflies.

Unlike some other species who lay their eggs carefully on the plants under the water, these dragonflies lay by dipping their abdomen briefly in the water and wiggling the tip to shake the eggs loose. She was so fast I struggled to get a good photo, but I was thrilled to see her. I really hope the eggs survive.

The pond is, without question, the best thing I ever created. If you have a garden and love wildlife, build one! Mine shows it doesn't have to be huge to be a haven. If you build it, they will most definitely come!

Hummingbird Hawk Moth (Macroglossum stellatarum)

I popped into the garden to put some kitchen waste in the compost bin and suddenly saw this amazing moth enjoying the Valerian flowers. After gasping out loud with surprise, I rushed back in to grab the camera (twisting my ankle in my excitement) and managed to snap these two shots before it flew away.


These are from being my best photos, but a first for both the garden and myself - I've always wanted to see one and never have, till now. It was amazing to watch - they are bigger than the worlds smallest actual hummingbird species. A large day-flying moth, it behaved just like a hummingbird too, which may seem obvious given the common name but I genuinely didn't expect it to resemble one quite so closely. It hovered perfectly to drink with its huge long tongue and darted rapidly from bloom to bloom.

One of the highlights of the garden so far this year.

7-Spot Ladybird (Coccinella 7-punctata) Lifecycle



The garden is filling with ladybirds, and rather wonderfully I have only seen one alien Harlequin so far this year. All the others are 7-Spots (as in the photo above), with just one 2-Spot making an appearance so far.

As well as adults, there are plenty of odd looking but very distinctive larvae.




These are even better (and faster) at devouring aphids than the adults are. They have a voracious appetite as you can see in the pictures.

Once the larvae have eaten their fill and grown nice and big, they pupate on leaves (and protect themselves by looking a lot like bird droppings) until a they emerge as adult ladybirds.

Newly emerged ladybirds are soft and near colourless, and gradually harden and gain colour over the first few hours of their new adult life.

Then they busy themselves eating more aphids until they find a mate and can produce eggs which will hatch into more larvae, and the cycle begins again.

All the photos on this post were taken (in my garden) within a few weeks of each other.

Monday 25 April 2011

Damselflies Making More :)


I spotted this impressive species of damselfly hanging around the pond over the weekend. Damselflies are closely related to dragonflies, but the key difference (aside from size) is that dragonflies hold their wings open (out to each side) at rest, whereas damselflies close their wings along their abdomen (as shown in the above photo).

The identification of this male was straightforward. There are only two red damselflies in the UK, the simply named 'Large Red Damselfly' and the 'Small Red Damselfly'. The small reds are smaller, obviously, and lack the black bands on the abdomen. Their abdomen is pure red.

I had only seen a couple of males hanging around, presumably waiting for a mate. One clearly had success, as I was extremely excited to observe a pair mating on the hedge today.

The female is the one at the bottom, with her abdomen curled up to the right, attaching to the male under his thorax to collect sperm. You can see the difference in colouration between the sexes quite clearly. The female is paler in this case (although not always), and has more black markings on her slightly broader abdomen.

They then proceeded to the pond, where the male remained attached while the female lowered her abdomen as deep as she could into the pond in various places to lay her eggs on the stems and leaves.

The male looks so odd; he just stands there pointing up in the air, waiting for her to finish. Most of the time he is 'standing' on his abdomen, not even holding onto anything.

There are already lots of damselfly nymphs from last spring getting big in the pond. I am so pleased we have another generation waiting to hatch out and grow.