Tag Archives: survival

Unseasonal Lepidoptera

I was walking in the countryside last Saturday morning around 8am and the weather was bright and sunny. It was also freezing and the grass was glistening  with the first frost of the Autumn. Despite the temperature it was a beautiful morning, enhanced by a deep blue, cloudless, sky and a three quarter moon, and as I wandered along a hedgerow a red admiral butterfly fluttered past.


Red admiral – not the one that fluttered by on Saturday, this one is from earlier in the year.

The colours of the red admiral are gorgeous. It was only when I studied a photograph of one that I really noticed the electric blue spots at the back of the wings and lining the tip of the forewings, and I wonder if the red circle is meant to resemble a fearsome Cyclopean eye to deter potential predators. Whatever the biological rationale they look stunning against the green foliage.

The appearance of the red admiral surprised me for two reasons, firstly because it was so cold, and secondly because in my part of the world all butterfly numbers seem to have been massively reduced compared to last year.

Last year was a really good year for butterflies and in early August, on a hot summer day, myself and my daughter went to a close-by fallow field and did the Big Butterfly Count organised by Butterfly Conservation (http://butterfly-conservation.org). We counted 9 species in our 15 minute survey window, including painted ladies which migrate to the UK for the summer from as far afield as Africa.

Painted lady

I think intercontinental migration is an astonishing feat of endurance for any creature, but for one as delicate and ephemeral as a butterfly it’s totally awe-inspiring. The odds stacked against any individual surviving such a journey must be mightily slim!

Conversely, it was very noticeable that the weather in 2011 was alot colder (it was the coldest summer since 1993 apparently) and butterfly numbers were significantly down compared to last year, in particular the common blue:

The aptly and, this year, inaptly named common blue. This one, with his wings wide open, is a male…

…and with his wings closed


Bizarrely, the female common blue is actually brown

She is looking ragged after a hard summer of mating and egg laying necessary to secure next years population. Common blues and brown argus butterflies can commonly be seen together, they are closely related and the brown argus and female common blue can be tricky to tell apart. She is distinguishable from the brown argus by her overall shape which is very similar to the male above, the white around the orange spots on the hindwing, the blue along the wingroots and the lack of a black cell spot on the forewing, all of which are not observed on the brown argus:


Brown argus sipping nectar from ragwort flowers above. And below revealing the slight differences in the spot pattern compared to the common blue female:


The brown argus can have a blue irridescent sheen when it catches sunlight at the right angle and the wing veins extend through the white wing border, which they don’t in the female common blue.

During a walk through our field at the start of August last year I would see tens of common blue, both male and female, but on the same walk at the same time this year I was lucky to see more than 2 or 3. The results from this years Big Butterfly Count corroborated my unscientific observations and it reports that common blue numbers were down by 61% in this years survey. I’m hoping we get a milder winter this year and a warmer summer next year so the numbers of these beautiful creatures can recover.

I took lots of cool butterfly pictures last year, but as it was before I started writing the Naturephile I was hoping to post them this year. But it didn’t quite come to pass so I’ll try to sneak some of them out under spurious pretexts to brighten up this winter!

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Hungry Heron

The current beautiful but brutally cold weather we are experiencing is lethal for many tiny creatures but also larger birds including our grey heron (Ardea cinerea). Cold spells such as the current one can result in the death of a large proportion of our heron population as they are unable to fish for their normal food supply when water courses freeze over.

Statuesque grey heron on Cambridge Science Park

The grey heron is a member of the family containing  bitterns and egrets and aswell as being the largest European heron is one of the largest UK birds.  They stand almost a metre tall with an average wingspan approximately 185cm and feed predominantly on fish and other creatures, in or close to water, such as frogs and other amphibians, but have been known to take small mammals, reptiles and insects.

Herons are considered to be among the more intelligent birds due to their ability to hunt and catch such a wide range of prey. One individual in Histon has recently exemplified this intelligence in an unusual and amusing way. It arrived in my friends garden looking very sorry for itself a few weeks ago at the start of the winter weather. My friend, being a thoroughly decent sort, gave it some fish from his freezer after which the heron decided to loiter. After several free and very easy meals of frozen pollock it took up residence in the garden and when the stipulated mealtime was not observed to its full satisfaction would sidle along to the door and tap on the glass with it’s bill to summon the next course.


The Histon heron
Waiting for a snack…

…and tucking in to a pollock fillet…
…then retired to a nearby vantage point for some post-prandial relaxation

As well as being sizeable birds heron can be stealthy and are extremely efficient fishermen. They catch smaller fish and eels in their bill but as you can see from the photographs the bill is a fearsome weapon and is used to spear larger prey. I once encountered a heron pecking at a prey item on the bank of the Lode at Wicken Fen, as I approached the heron flew away and I found an enormous pike on the riverbank, approximately 2 feet long (I don’t know if a heron would be capable of catching and killing such a big fish) and it had made a surgical incision running from top to bottom immediately behind the gill and had been busy extracting the entrails.

Heron are not migrants to or from the UK but they have been known to cross the English Channel and turn up in France and the Iberian peninsula. They have various common names including the ‘hernshaw’ in Lincolnshire, the ‘marshmens harnser’ in Norfolk and a ‘shiterow’ or ‘shiteheron’ thought to originate from the herons habit of defecating when disturbed prior to take off!

So if your pond is overstocked with fish in the freezing cold weather and could use  some thinning out why not spare a thought for the struggling heron and break the ice so he can refuel and stave off the cold.