Thursday 31 July 2014

Week 28: Hemel Hempstead Barn Owls

Southern Hawker dragonfly, Bovingdon Brickworks (perched after hunting by the Buddleja)

    Southern Hawker, Brickworks
    Bramble blackberries, Brickworks

After fledgling Wagtails and nestling Swallows; riverside damsels and hunting dragonflies; meadows of moths and butterflies, I hadn’t got a clue what wildlife wonder I might encounter this week. In my wildest dreams, I don’t think I could have conjured up what transpired.

After months of not feeling up to going out beyond about 6pm, the sunset on Monday evening, combined with improved health, tipped the balance. Box Moor Trust land set against a fiery sky, seemed like a good plan. Of course, the inevitable happened. By the time I got out of the car, the colours had faded and the moment had passed. Still, it seemed a pity to waste escaping the house and so off I set. I debated whether or not to bother with the tripod but decided that if I left it in the car, I was bound to regret it.

I might have missed the sunset but I came across something far more exciting. Over the past month or so, there have been a number of Barn Owl sightings around Hemel Hempstead. On the Box Moor Trust Moth, Bat and Glow Worm evening (27th June), the group had enjoyed watching a bird quartering over the field between Chaulden Lane and the railway bridge. Dan Forder (of Hemel Birding fame) had seen a bird near the M1 Jun 8 on 7th July. And, on Monday evening, as I walked over Trust land, I chanced upon one of these beautiful creatures perched in a tree. It eventually took flight, soared silently over my head and away. Utterly magical and boy was I glad I had the tripod with me! The light was almost gone but I was able to get some ropey video footage before darkness fell. Special thanks to my talented Sister, her choir and the Robin soloist(!) for the backing track. A couple of years ago, on a sultry summer evening, the choir threw open the hall doors as they sang a cappella. Nature joined in. The resulting piece is candid and unique. A male Robin sings his evening song and the choir swells to accompany him.

Having done a little reading about Barn Owls, it seems to me that the females have the right idea. Grab yourself a monogamous mate and sit around all evening whilst he goes off and finds the food. Once eggs are laid, snuggle up inside the nest site, don't bother to build a nest (who needs twigs when regurgitated pellets will do?!), don’t bother to wash, and lap up meals-on-tap from the doting male. Result!

Ten Barn Owl Facts, shamelessly copied and pasted from the internet (with a few minor additions). More facts here.
  1. The barn owl was voted Britain’s favourite farmland bird by the public in an RSPB poll in July 2007. 
  2. Historically, the barn owl was Britain’s most common owl species, but today only one farm in about 75 can boast a barn owl nest.
  3. Barn owls screech, not hoot (that’s Tawny owls). 
  4. The barn owl can fly almost silently. This enables it to hear the slightest sounds made by its rodent prey hidden in deep vegetation while it’s flying up to three metres overhead.
  5. The barn owl’s heart-shaped face collects sound in the same way as human ears. Its ears are placed asymmetrically for improved detection of sound position and distance, and it does not require sight to hunt. Its hearing is the most sensitive of any creature tested.
  6. Barn owls are non-territorial. Adults live in overlapping home ranges, each one covering approximately 5,000 hectares. That’s a staggering 12,500 acres or 7,100 football pitches!
  7. It’s not uncommon for barn owl chicks in the nest to feed each other. This behaviour is incredibly rare in birds.
  8. In order to live and breed, a pair of barn owls needs to eat around 5,000 prey items a year. These are mainly field voles, wood mice, and common shrews. One of the most unusual feeding records is of a barn owl catching flying hawk moths.
  9. Though barn owls are capable of producing three broods of five to seven young each year, most breed only once and produce, on average, only two and a half young. 29 per cent of nests produce no young at all.
  10. 91 per cent of barn owls post-mortemed were found to contain rat poison. Some owls die as a direct result of consuming rodenticides, but most contain sub-lethal doses. The effects of this remain unknown.
Barn Owls are a Schedule 1 protected species. It’s fantastic that there appears to be a number of birds locally.

Finally, this week's oak...

And, Dellfield in Summer...

It seems incredible that just 3 months ago, this meadow was carpeted in Cowslips…

Friday 25 July 2014

Week 27: Brimstone & Whistle-stop Summary

A scorcher of a week and with limited time and energy, it was a bit of a whirlwind tour of the lands yesterday. As the photograph above suggests, a Buddleja bush and a Brimestone butterfly were involved. My foray into wedding photography was brief and finite but seemed to go ok. That being said, give me wild creatures over civilised homo sapiens any day of the week.

Under clear skies and rising temperatures, I wandered over Bulbourne Moor and Hardings Moor, eventually making my way up to Roughdown Common. There are still a few damselflies on the river (Common Blue, Blue-tailed and Banded Demoiselle). The nettles on the riverbank east of Station Road are Camp Caterpillar. I couldn’t find anything more interesting than a glut of Small Tortoiseshells though.

The dell at Lower Roughdown had more spots than a Dalmatian, with Six-spot Burnets everywhere I looked, including a mating pair. A few tired Ringlets remain along with Meadow Browns, Gatekeepers and fresh Peacocks.

Up on Further Roughdown, in addition to the species already mentioned, there were a few Marbled Whites and the second brood of Common Blues were zooming around, their speed seemingly proportional to the 30 degree heat. The wild Marjoram is in flower and the Honey Bees (Apis mellifera) were making the most of it, hard at work. Overhead, 3 Red Kites soared on the day’s thermals.

    Wild Marjoram (Origanum vulgare)
    Honey Bees (Apis mellifera)

I only managed a very brief visit to the Brickworks in the afternoon. The Buddleja at the north-east end of Baker’s Wood is worth a visit. I’ve never seen so many Peacock butterflies in one place (in addition to the Brimstone mentioned earlier). The fruit of the bramble bushes is beginning to ripen and, in the meadow with the mound, more spots. I lost count of the number of Six-spot Burnets.

Finally, to Dellfield and the oak. The Kestrel family are still using the trees in Ryders as a base. I spotted 2 birds hunting over the meadow and a Muntjac trotted up the central path to disappear from sight.

The lush green of the springtime meadow has given way to the parched grasses of the summer.

Left, 19 May 2014; Right 24 July 2014

Wednesday 16 July 2014

Week 26: Purple & Gold Celebration

I am slightly distracted this week by the prospect of being one of a handful of “unofficial photographers” at my friend’s wedding this weekend. I did tell her that I hadn’t done any indoor photography (unless you count Swallows in a barn?!) and that if you haven’t got feathers or antennae, I’ve little idea as to how to go about capturing your best side. Bizarrely this didn’t put her off!

With a busy week ahead, Monday was the only day I was going to be able to get out around Box Moor. At Dellfield, I could hear the family of Kestrels were still around and, up at the Old Barn, the young Swallows were still squirming in their nest*. Making my way into Hay Wood, I could hear a Green Woodpecker, likely a fledgling, constantly calling to a parent. The highlights at the revitalised bird feeders were a Great Spotted Woodpecker, Jay and plenty of Coal Tits, with Nuthatches calling close by.  Emerging from the cool, shady woods I caught sight of a Buzzard circling overhead and then walked back down towards the Oak. I guess this week’s photograph is all about the rare expanse of blue sky.

Late afternoon, on the back of a warm, sunny day, I thought the Brickworks might be a good place to explore. I was hoping for a new moth or butterfly to mark the six month point of this project. In fact, the first “new find” was a Cinnabar moth caterpillar, followed closely by what I later learned was the remains of a Burnet moth chrysalis. There were a couple of fresh-looking 6-spot Burnets in the area so it had perhaps been home to one of those. The scrub really was alive with butterflies but two finds in particular made my heart skip a beat.

Cinnabar moth caterpillar

    Marbled White
    Burnet moth chrysalis remains

Firstly, this week’s new moth and my “celebration” for reaching the 6 month mark in Project 2014 was a tiny but beautiful Common Purple and Gold moth (Pyrausta purpuralis). It’s not fussy as to when it flies, day or night, and prefers dry grassland and chalky downland habitats. The larval foodplants are corn mint (Mentha arvensis) and thyme (Thymus). Most importantly, it was new to me and a real joy to discover. My photograph doesn't do it justice.

Unfortunately, my new friend was rather flighty and didn’t settle for long before I lost it. However, whilst I was trying to relocate it, I came across my second exciting find of the day. It seemed strangely fitting that after the last 2 weeks of developing affection for the little orange Skipper species, that this week I should run into a mating pair of Small Skippers. Unlike some species, which are easily disturbed, this pair were apparently welded to the flower head! Strong gusts of wind didn’t shift them nor did my carefully and strategically manoeuvring the stem slightly so as to be set against a predominantly dark backdrop. Sitting on the ground, photographing a pair of relaxed, mating butterflies; warmed by the sunshine and, behind me in the bushes, the sighing of Bullfinches. The picture of contentment.

More than satisfied with the day's exploring, I headed home for a cuppa.

Ben and the moth trapping team have continued their nighttime endeavours. Last week's reward at the Brickworks was a superb Scarlet Tiger moth. This is an extremely rare moth in Hertfordshire and therefore a highly significant find for the site. Take a look at Ben’s great blog for a photograph and a more detailed report of the evening.

Finally, I’ve added a new tab at the top entitled “The Oak: Week by Week”. This is the series of 26 photographs charting the Oak over the last 6 months. It’s a visual summary and, if you click on a photograph, it’ll take you to that week’s blog post.

Right, pre-wedding photography angst is kicking back in. I’m not sure who is going to be more nervous on Saturday. The bride or those of us who have the responsibility to record the day for posterity! Wish me luck!

* a quick visit to check on the Swallows this afternoon revealed an empty nest and a quiet barn.

Saturday 12 July 2014

Week 25, Extra: Barn Swallows in a…Barn

Friday morning was grey and drizzling. The perfect weather, thought I, for standing inside to observe and film nature. I’d learned from Liz Warriner (a member of the Trust’s hard working Conservation Volunteer team) that a pair of Swallows were raising a brood in the roof beams of The Old Barn at Westbrook Hay. Liz had taken some lovely photographs and I was keen to join her in getting a record of this species breeding on Trust land.

The video footage opens with a view of The Old Barn and a parent Swallow swooping in...and then out (easy to miss!). The penultimate clip, from a distance, shows a parent collecting the fecal sack from a nestling and carrying it away. (I should have known that as soon as I changed lenses to film the wide angle view, the action at the nest would get more interesting. Of course, neither parent repeated the behaviour once I’d reverted back to filming close up. C’est la vie).

It is probably just a matter of days before they fledge. Such fantastic little birds to observe and to enjoy at close quarters. It is impossible not to be impressed by those wonderful tail streamers and long, sleek, super-athletic wings. Over the coming weeks, the birds will build up weight and strength and then head off on their marathon migration to South Africa.

Wednesday 9 July 2014

Week 25: Hello Essex & Kestrels Fledge

My life is complete! Well, it is in terms of finding all 3 species of little orange Skipper butterflies on Box Moor Trust land. More than that, I can’t say.

My wanderings this week started with a quick visit on Monday morning to Dellfield. As soon as I opened the car door, I could hear young falcons calling. The first creature to come swooping past me as I entered the meadow was an adult Kestrel. I didn’t catch whether it was the male or female but it was heading for a noisy youngster located high up in the trees in Ryders (the field west of Dellfield). This is exactly the same area I’d seen a pair of Kestrels mating in early May so I guess springtime shenanigans were successful. Anyway, once food had been delivered, the fledgling took a short flight to a more exposed perch, giving me the chance to get a photograph, albeit a rather distant one. It and its fellow offspring (3 in total, I think) were constantly calling for food and attention. The universal plight of new parents!

The view across Dellfield towards Ryders. The line of trees, from left to right, runs along Ryders' border with Dellfield. The Kestrels were initially in the right corner: the trees you can see, if you look between the Oak and its neighbouring Scots Pine.

When it comes to photographing the Oak, I sometimes have an idea of what I’m after. Other times, it’s a case of responding to what’s in front of me. On Monday, it was the latter. Early on, I’d taken a few shots but none that satisfied. As I walked back down from visiting the pond on Preston Hill, the Oak was drenched in shadow and set against the wisps and puffs of a striking cloud formation. I quickly got into place and timed the shot to coincide with the Oak remaining in silhouette whilst the meadow in the background was released into the light. I love how clouds passing over the sun can create such fleeting drama on an otherwise static scene. Blink and you'll miss it.

Now to this week’s life completing experience (compensation perhaps for watching Federer nearly, nearly win...but actually lose in the final on Sunday). Tuesday, I plumped for Bovingdon Brickworks. Butterflies galore! And, within about 10 minutes of arriving, there in front of me, settled on a delicate pink flower, was an Essex Skipper butterfly (Thymelicus lineal) (ref last week's post). They emerge slightly later than Small Skippers (the end of June rather than mid June). Their inky black-tipped antennae being the clinching ID feature. You do have to be a little careful (apparently) as Small Skipper’s antennae can “show very dark brown undertips, whilst others have confusing amounts of black on top of their antennae”. The other quite noticeable feature, especially when comparing the photographs, is the shape of the forewing. The Essex Skipper’s appears to be squarer. The colour also seems to be brighter: a feature noted by Charles Smith but qualified later as perhaps being a result of the later emergence and therefore fresher state of specimens. However, my photographs were taken 9 days apart so perhaps the Essex Skipper truly is a brighter butterfly than the Small Skipper. For a more detailed comparison of Hertfordshire’s Skippers see this excellent webpage.

All 3 orange Skipper species, photographed on Box Moor Trust land

Finally, a few metres beyond the Skipper, I found a Creeping Thistle hosting 5 Common Red Soldier Beetles (Rhagonycha fulva). “Adults feed on aphids, and also eat pollen and nectar. Larvae prey on ground-dwelling invertebrates, such as slugs and snails, and live at the base of long grasses. The adults spend much of their short, summer lives mating and can often be seen in pairs.” The literature doesn’t lie!

POST SCRIPT August 2016 

With time and experience, I am no longer convinced the Skipper photographed above and labelled as Essex Skipper is indeed an Essex Skipper. It could be but a view of the underside of the antenna would be conclusive and I didn't manage that, unfortunately.

Friday 4 July 2014

Week 24: A Novel Use of Nettles & Family Wagtail

The first week of July and yet, applying my mind is like trying to rouse a tiny dormouse, snuggled up in a downy nest, seeing out the winter. That is to say, the creative juices have run dry. I’m adopting the less is more approach when it comes to words and will perhaps rethink things from week 26 onwards. By that point, the project will have been going for 6 months and might be worth tweaking/reworking/abandoning. Who knows.

Ok, first up, it’s a female Banded Demoiselle.

This one was fluttering around the common nettles by the river, east of Station Road on Harding's Moor. At one point it looked as though it was ovipositing some 15 metres from the river (pardon?!). That had me scratching my head until someone suggested that perhaps the Demoiselle was using the bristles on the nettle leaf to clean itself. That made perfect sense, especially when I noticed that apart from the mating claspers (cerci) and ovipositing appendages (stylus), the damselfly had a foreign object hanging from its rear end (nice!)!

After the Broad-bodied Chasers, I’ve seen an additional 3 species of dragonfly this week on Trust land. A few Emperors (river Bulbourne, Gadespring cress beds and Preston Hill pond), a Southern Hawker around Fishery Moor and a Common Darter (photographed, left) at the Preston Hill pond.

Most noticeable this week, though, has been the number and variety of butterflies out and about. Marbled Whites, Commas, Small Tortoiseshell, Meadow Browns, Ringlets, Red Admiral and Small Whites to name but a few. Add to that, Small and Large Skippers out in good numbers now. I have attempted a Skipper ID comparison (below) from photographs taken at the Brickworks this week.

Small Skipper (Thymelicus sylvestris) (left); Large Skipper (Ochlodes sylvanus) (right)

3 Key Differences
  1. Size (wingspan): Small Skipper 27-34mm; Large Skipper (male) 29-34mm, (female) 31-36mm. Their wingspans overlap but the Small Skipper is noticeably smaller in the field.
  2. Shading on the wing: Large Skipper - dark shading/patterning on forewing
  3. Antennae: Small Skipper - orange/brown rounded tips; Large Skipper - hooked tips. I’ve not found an Essex Skipper (yet) so don’t have to worry about that!
Up on Further Roughdown, I came across a pair of mating Ringlets (Aphantopus hyperantus). Their larval foodplants are grasses [Cock's-foot (Dactylis glomerata), Common Couch (Elytrigia repens), False Brome (Brachypodium sylvaticum), Meadow-grasses (various) (Poa spp.) and Tufted Hair-grass (Deschampsia cespitosa)].

And, near Old Fishery Lane, a Gatekeeper butterfly (Pyronia tithonus) was warming itself, perched on nettles. This is another species that relies on grasses as larval foodplants [Bents (various) (Agrostis spp.), Fescues (various) (Festuca spp.) and Meadow-grasses (various) (Poa spp.). Common Couch (Elytrigia repens)].

Early on in the week, Monday, I think it was, I was walking across Station Moor when I suddenly heard the distressed calls of a Grey Wagtail. I looked up to see a Sparrowhawk lazily flying south, carrying something in its talons. The diminutive Grey Wagtail was in hot pursuit as if its yellow go-faster-stripes were sufficient protection against such a predator. I did wonder if the Sparrowhawk had made off with a young Grey Wagtail. Anyway, on Thursday, I was able to get back to the area and was pleased to discover that, whatever had been going on with the Sparrowhawk, it had not prevented the Grey Wagtail pair from successfully fledging at least 2 youngsters this week by the Fishery Road canal bridge. I’ve put together some video footage of the parents and one of the fledglings. It was a task and a half to capture significant moments when the wind wasn’t gusting and making the footage unusable. Some clips are a little ropey (to put it mildly!) but hopefully that doesn’t detract too much from enjoying the events.

Finally, this week's Oak photograph.