Monthly Archives: August 2014

Isle of Wight Part 2

Posted on August 11, 2014 | 9 comments

The IoW avians:

We took our annual holiday two years running at Shanklin on the Isle of Wight, and one thing I noticed during the first visit was that there were ravens on the cliff face behind the beach at Shanklin. As I didn’t manage to take any close-up photographs of them on the first visit I resolved to try a bit harder the second time around.

Then one afternoon I found myself on the seafront with the kids and the usual gulls were wheeling and squawking in the air:

Herring gull – Larus argentatus (Dansk: Sølvmåge)

I like herring gulls, their shrieking call is reminiscent of fun-filled childhood trips to the seaside. And it makes me laugh how easily they overcome their natural fear of humans and come right up close to try to scrounge a chip.

And another gull which frequents the coasts of the UK, but which I see more of on the fields inland is the black headed gull:

Black headed gull, Chroicocephalus ridibundus (Dansk: hættemåge) – undercarriage down for a landing on the beach

Having touched down a quick pause for a pre-prandial scratch before poking around in the silt for something to eat

And while the gulls were doing their thing I noticed a big black shape on the cliffs a few hundred metres away which I thought could be a raven. So I chivvied the kids along the beach to get closer and sure enough it was indeed a raven. It flew down from the cliffs onto the beach and landed around 30-40m away but as I was of the opinion that ravens would be like the other crows, not terribly comfortable being in close proximity to humans, I gathered the children close and told them to be calm. But as we stood and watched it strolled down the beach towards us and didn’t appear to be remotely fazed by our presence, or for that matter, anyone elses:

Close encounter with a raven (Corvus corax, Dansk: ravn)

He strolled on past with a purposeful gait and what struck me was the size of him. Ravens are huge! I’d read before that they are the size of buzzards and seeing one this close it’s easy to see they really are.

So for comparison, an obliging rook posed in the background, and even though the rook is 5-10m further away the size difference is stark. There’s no confusing this chap for any other type of corvid!

And the reason the raven was behaving as bold as brass was that it was on a mission to examine the contants of a litter bin for a late afternoon snack:

First it made a small incision with its powerful beak – one of natures tools that’s magnificently fit for purpose. Once access was gained, it proceeded to extract the contents through this hole and snaffle up all the pieces of food jettisoned by that afternoons beach goers:

When I left it was still emptying the bin and was only distracted once when a large group of noisy folk walked right past, but he just hopped away a few metres and waited for them to pass before burying his head inside the bin once more to continue the meal.

I really like this series of shots because it shows a spectacular and enigmatic bird being incredibly resourceful, and it’s the first time I manage to get really close to a raven.

Some years ago I went kayaking in the Johnson Strait between British Columbia and the Canadian mainland to see orcas, and while I was there I learnt a bit about the indigenous people of that region, the Haida indians. As with many indigenous folk, they had a conservation minded and mystical relationship with their environment because their very survival depended entirely on the forests and oceans and the inhabitants thereof.

And one of the creatures they held in particular reverence was the raven. A modern day Haida called Bill Reid has written a book consisting of a series of short stories based around the orca, the eagle, the bear and of course, the raven, all from Haida legend going back centuries to a time before Europeans intervened and ruined everything. If you ever stumble across a copy buy it and enjoy it, it’s called ‘The Raven Steals the Light’ (ISBN 1-55054-481-0).

9 Comments

Posted in Beach walks, Birds, Coastal walk, Gulls, Isle of Wight, Ornithology, Seabirds, UK wildlife

Tagged black headed gull, British Columbia, Corvus corax, Haida, herring gull, Johnson Strait, raven, The Raven Steals the Light

Histon Harvest

Posted on August 10, 2014 | 9 comments

All the posts from my home patch have focussed on the wildlife and the impact of humans on the wildlife without much focus on the human activities per se. So as it’s harvest time now, or it would be in a normal year, and the harvest is such an important event in human interaction with the countryside, I want to devote this post to it.

The harvest was nearly all done and dusted by the last week in July here this year, which is a good 2-3 weeks earlier than in a climatically normal year. These pictures are from last year when the bulk of the harvest took place in the second and third weeks of August. The crops vary in my local fields, and wheat, barley and oil seed rape are commonly planted.

Leviathan of the Fens – the combine harvester – gathering the crop

Last year it was either wheat or barley so when harvest time began it heralded the arrival of some seriously big machinery. The speed with which these gigantic beasts gathered the grain and separated it from the straw and depatched the produce was breathtaking.

Dancing a duet with the tractor – it was all perfectly choreographed

The grain was unloaded into a trailer drawn by a tractor and the straw was jettisoned out the back to be simultaneously baled by a second tractor towing a baling machine :

And a quick change of partner for a waltz with the baler

The whole operation lasted just a few hours and was done with military precision and at the end all that was left was neatly arranged piles of bales amidst acres of stubble. A few years ago I was talking to a farmer in a pub near Cambridge and he told me that the harvesters have onboard computers which record how much grain is harvested from every part of the individual fields, and where yields drop it is all mapped via GPS so when fertiliser is applied prior to the next sowing operation, more will be applied in the areas of the fields which delivered the lower yields during the previous harvest. And of course, with that degree of efficiency applied to the whole process there is nothing left over for the wildlife as there was in the years pre-agro-intensification, and that’s a major reason why species such as tree sparrow, turtle dove, yellowhammer etc, are struggling. I’ve noticed in these fields that after the harvest nearly all the birdlife including yellowhammer, skylark, corn bunting, linnet and reed bunting all drastically decrease in numbers until the next springtime.

And whilst all that was ongoing there was another baler tidying up an adjacent field which is managed by a different farmer:

These monstrous bales aren’t the type that can be thrown around by a couple of farmhands and manually stacked on a flatbed trailer, they are around my height in diameter and require more big machinery to move them:

Another homeless (and endangered) farmland bird wondering what’s happened to his shelter and his meals:

A bewildered looking grey partidge (Perdix perdix) forced to the margins after the harvest

And of course, at this time of year, the grain isn’t the only harvest:

Juicy ripe plums hanging in the hedgerow

Another ramification of intensive farming is the destruction of the hedgerows. It’s something we wised up to in this country some years ago, with regard to grubbing them out, but nowadays farmers insist on attacking the ones that remain with flails (if anyone knows why they spend money and time doing this please let me know), including the one where these plums were growing. Not only does this thin the hedge right down so it provides less cover for overwintering birds, rodents, insects etc, the trees and bushes which grow there and provide food for the wildlife are producing less of these gorgeous fruit. So the wildlife is getting squeezed into a smaller and smaller fraction of the countryside and their shelter is under constant attack and their food source is constantly depleted. I think it’s not a good way to manage the countryside.

At harvest time with all the dust in the air it makes for some glorious sunsets

But on the optimistic side, I reckon it is possible for farmland to be managed to produce sufficient food for humans and still sustain our wildlife. I just hope that as a species we wise up before it’s too late. And at the risk of stirring up controversy… maybe we should simply learn not to waste so much.

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Posted in Agriculture, Cambridgeshire, Countryside walks, Humans in the countryside, Walks around Cambridge and Histon

Tagged agriculture, countryside management, hedgerows, human intervention, intensive agriculture

Isle of Wight 2013

Posted on August 7, 2014 | 14 comments

Part 1 – Lepidoptera

I’ve already grumbled in earlier posts about how the weather over the last three years leading up to 2014 was cold and unpredictable here in the UK, and how it had a very bad effect on our wildlife. In particular, overall numbers, and numbers of species, of butterflies, which are very sensitive to environmental change, seem to have been dramatically affected over those three years here in Cambridge at least.

But last year whilst on holiday on the Isle of Wight I took a walk from Shanklin up to the old WW2 radar station which is the highest point on the island, and apart from a flypast by a peregrine falcon, the most eyectaching natural phenomena were the butterflies, which seemed to be in direct contrast to the previous three years.

Comma – Polygonia c-album

The first part of my route took me through a wooded area bound by sea cliffs on one side and farmland on the other. A huge buddleia bush overhung the pathway which was hosting numerous species of butterfly, including the comma, above, and a painted lady, of which I’d seen plenty in 2010 but virtually none in the intervening years when the weather had turned bleak.

Painted lady – Vanessa cardui

The comma is resident to the UK and in recent years its numbers and range have actually increased and this has puzzled the entomologists as it is bucking a general trend amongst all butterflies here in the UK. in contrast, the painted lady is a handsome migrant which, according to my field guide, may or may not show up in the UK, consequently the entire population depends on immigration from Africa. But that raises the question what happens to the adults that are born here?

But since my guide was published, some research has been published where populations were tracked in and out of the UK on their migration routes by radar, and it revealed that painted ladies leave the country at high altitude – 500-1000m – where they can’t be seen by eye. The application of technology is revealing many hitherto unknown phenomena about many species and it’s interesting that up until now it was thought the whole UK population of painted ladies died out each year simply because they fly back just out of visual range. And even more amazingly, it has now been discovered that this species takes up to six generations to make a circular 14000km (9000 miles) round trip from the Arctic Circle to Sub-Saharan Africa!

Which raises another mind boggling question: how is it hard wired into this tiny creature to make successive steps of this awesome migratory feat, covering half the globe, all in the same direction, at any one time? Unbelievable! But on the other hand, if populations on a previous leg of the journey take a hit for whatever reason it may be the explanation of why population size can vary so much from year to year in the UK.

Common blue male – Polyommatus icarus

After emerging from the woods I climbed a steep incline, crossing the main Shanklin to Ventnor road and up the chalk downland of Boniface Down towards the WW2 radar station. Consequently, the terrain and the vegetation changed and so did the butterflies. The common blue is another species which I sighted frequently before the three year cold snap of 2011-14, but this male was the first one I’d spotted for a while.

Silver Y moth – Autographa gamma

The silver Y – it’s easy to see how it got its name – is a migrant moth which isn’t peculiar to chalk downlands and can be seen in most habitats, including the farmlands here around Cambridge, and this one was soaking up the sunshine on the down.

Marbled white – Melanargia galathea

But the real gem of this trip was the marbled white, of which there were numerous examples fluttering around the down, and this one was sipping nectar from a greater knapweed flower. The marbled white is a UK resident and its favoured habitat is chalk downland.

Emerging on the top of the downland the vegetation changed to primarily low scrub consisting of acres of thistles which were home to more gatekeepers than I’ve ever seen before in one spot, I’m not exaggerating when I say there were literally hundreds of them. The information board at the entrance said that small coppers were also in residence but I only saw one and unfortunately it didn’t settle, which was a pity because they’re beautiful little brown and orange chaps and I wanted to get a photograph of one to share. Oh well, next time.

Gatekeeper – Pyronia tythonus – this one is a male, identifiable by the brown patches on the forewings, the ‘sex brands’

During the winter of 2013-14 and so far through this year the weather has warmed up, the cold, the rain and the high winds have all abated allowing many species to start to recover. It’s been a good year so far for butterflies and dragonflies, and hopefully lots more insects and the other creatures that predate them. The resilience of the natural world is astonishing, but I’m hoping we get another couple of mild years so the recovering wildlife can consolidate its numbers before the next big change in the weather.

The views from the top of Boniface Down were lovely. The cliffs on the southern edge of the island falling away to the English Channel were to the left, and when I looked north I could see mainland England. It’s not discernible in this photograph but the Solent and the south coast of the mainland are in the distance:

The only bird I managed to photograph up there was this little fellow who I think is a meadow pippit:

The pippits were very busy feeding youngsters, toing and froing across the scrub with beaks full of insects.

And the other reason I hiked up the hill was to see the old radar station at RAF Ventnor at the top of Boniface Down. This was one of the original installations set up before WW2 and was instrumental in detecting and reporting the massed attacks on southern England by the Luftwaffe during the Battle of Britain.

The remaining pair of radar towers at RAF Ventnor – there were originally six

The station was twice bombed by the Luftwaffe and I believe it holds the dubious distinction of being the only radar station to be destroyed by the enemy!

14 Comments

Posted in Birds, Butterflies, Climate change, Coastal walk, Countryside walks, Insect migration, Insects, Isle of Wight, Lepidoptera, Migration, Moths, Ornithology, Songbirds, UK wildlife

Tagged Boniface Down, butterfly migration, chalk downland, comma, common blue, gatekeeper, isle of Wight, Lepidptera, marbled white, meadow pippit, painted lady, radar tracking, RAF ventnor, silver Y moth, WW2 radar station

Home grown dragons

Posted on August 6, 2014 | 17 comments

One end of my front garden is curved and tapers to a point and was pretty much dead space, so last year I decided that I’d turn it into my own tiny nature reserve and make a pond. The street side of the garden is lined with beech hedge and the open end is bound by a hazel tree which I planted there 5 or 6 years ago, so it is an enclosed space which I hope will remain fairly undisturbed, apart from my forays to photograph the wildlife that takes up residence.

In order to try to maximise the wildlife potential I followed all the instructions on how to create a wildlife pond, so it’s around 30cm deep (which is enough to prevent the bottom from freezing even during the coldest UK winter) and was seeded with plant life and minibeasts from my friends pond, and there are no non-native species and no fish. The water went into it in February this year from my water butt (tap water contains chemicals which are not good for a balanced wildlife pond) and it’s remarkable how rapidly nature has taken hold. As well as all the beasts added by me which seeming to be flourishing, it has been discovered by various species of dragonfly, butterfly and hoverfly, and I put twenty common frog tadpoles in from another friend’s pond, of which at least one reached adulthood.

Common darter female (Sympetrum striolatum) perched on an iris leaf

In the corner of the garden where the pond is I’ve let the grass and wild flowers grow and I mow a path all the way round, so I can view it from all angles, and in one corner a small patch of stinging nettles is allowed to grow unhindered. In this way I’m hoping that eventually the grassy area will reach a balance with local wild flowers and provide a suitable habitat for a few more insect species. As well as the ubiquitous white butterflies, peacocks, and other regular garden butterflies visiting the garden, since the completion of the pond I’ve also added gatekeeper and speckled wood to my garden species list.

Common darter male drawing breath after a hard days mating

Apart from the introduced tadpoles, the most interesting visitors to my little zoo have been the dragons, of which I’ve seen at least 3 species of damsel, one darter and one hawker species, all either settled around the pond or hunting over it. Of these, the most notable have been the common darter which are very common in my part of the world, and are often very easy to photograph, and consequently the most frequent species shown here in my posts. But I think they’re incredibly photogenic! And this year in the garden I’ve managed to capture several aspects of their reproductive life cycle.

Common darter tandem pair

This pair, in the midst of copulation, were being constantly harassed by a lone male which had taken up defensive positions on the pond and was defending it vigorously. But they were not to be deterred and completed copulation and began ovipositing in the pond despite the unwanted attentions of the loner.

The male common darter has primary and secondary genitalia, the primary genitalia, located on the last abdominal segment, produce the sperm which he transfers to the secondary genitalia on abdominal segment 2 (counting along from the thorax), which contains the penis with which he inseminates the female. Transfer of sperm is done prior to clasping a mate with the anal appendages or ‘claspers’ at the ‘pronotum‘ (a plate of the exoskeleton at the back of her head) in the case of damselfies (Zygoptera), or by the head in the case of the Anisopteran dragons. She then attaches her genitalia to the sperm-containing secondary genitalia of the male and fertilisation ensues.

The tandem pair, now fertilised, looking for places to oviposit

Once the female had been fertilised, they flew around the pond and when they had identified a suitable location the female swung her abdomen downwards to eject an egg into the water. Some species of dragonfly search for specific locations underwater, such as the underside of leaves or within the stems of water plants, to lay their eggs, but the common darters were placing them directly into the water. Consequently they darted swiftly to and fro over the pond and the ovipositing movement was extremely rapid, making photographing the event a challenging task, but I managed one half decent shot:

The next chapter in this story will be when the eggs hatch to release the larvae into the pond, which happens 2-5 weeks after laying the eggs. Dragonfly larvae are voracious predators but there should be sufficient other insect life in the pond to keep them sated, and if I can catch one I’ll post the pictures later. And hopefully I can pphotograph one as it emerges from the water and metamorphoses into the adult dragon, which should happen next year if they survive.