Riversearch December 2015

Once again I’d left my Riversearch survey til the last moment, so ended up squeezing it into my busy Christmas Eve. (I did get questioned by a passerby as to why I was out ‘working’ on Christmas Eve, who couldn’t quite believe that was how I choose to spend my leisure time). The weather wasn’t very tempting for a riverside stroll that morning. But rain is no excuse to put off a Riversearch survey – in fact, it may be better, as it allows you to see any runoff from fields, roads and pipes. So I donned my wellies and headed out. By the time I got out there, the rain had eased off somewhat – there were even glimpses of blue sky.

Like the rest of the country, we’ve had quite a lot of rain lately. Thankfully we’ve escaped the flooding other areas had. While the ground was boggy and the water level high, at least I could walk through the meadow – exactly two years ago I wouldn’t have been able to do that, as it was completely submerged.

Winter is always a good time to do the survey for my stretch – the nettles, himalayan balsam and other plants have died back enough to allow me to see a lot more of the river bank than usual. The main finding of interest was pollution coming from a few of the pipes in the riverbank. There was quite a lot of white foam on the river, building up in places, but that seemed to be coming from further upstream. I don’t know what it was, but definitely something to report.

Aside from that, the only other notable finding was a mystery nest, lodged a couple of feet up a sapling on the riverbank. Any ideas what might have made that?

Who’d live in a nest like this?

Advertisement

May 2015 Riversearch

I chose another glorious afternoon for my May Riversearch survey. It’s a joy to be out and about in the May sunshine – the trees wearing their new gowns of leaves, every wildflower bursting with the joy of life.

The River Mole, at the foot of Box Hill

Butterflies and damesflies were busy making the most of the good weather, and birds were busy with bringing up youngsters.

Brimstone butterfly on a red campion, among cow parsley

Banded demoiselle damselfly

The river was back to its normal level, with the Stepping Stones easily crossable (if a little slippery). There were no signs of pollution, and no fresh fly tipping.

Few people were out and about – just a few youngsters enjoying sitting round, listening to music and chatting (enjoying the start of half term, and a brief respite from exams).

I came across an intriguing hole in a tree trunk – not sure who was using it.

So much has grown up since my last survey, it was much harder to see the river. A thick wall of waist-high stinging nettles defeated me in some places – I’d need thicker trousers before I attempt to force may way through them! By the time of my next survey they may well be as tall as me, limiting the thoroughness of my data collection.

Stinging nettles

Sadly not everything was so positive. When I looked under the bridge to check for signs of otters I came across someone sleeping rough. Not a great place to set up camp for any length of time, as though the river level was ok, any heavy rain and the river would easily cover where the person was sleeping.

The other negative to my survey was signs of Himalayan Balsam returning. I only spotted a few metres of the stuff, but give it a month or two and it’s likely to have engulfed much more of the riverbank.

Himalayan Balsam emerging again

 

Box Hill and The Lark Ascending

My walk on Box Hill the other day was lovely. The sun was shining and the slope alive with butterflies. But I felt that something was missing. There was no skylark song.

I recommend you listen to this YouTube video while reading the rest of this post. You’ll thank me for it!

Skylarks are plain-looking brown birds, smaller and duller to the eye than starlings. But to hear them sing is to have your ear filled with molten silver, and your thoughts lifted to the heavens.

Patrik Åberg, XC27004. Accessible at http://www.xeno-canto.org/27004.
Creative Commons Attribution-NonCommercial-ShareAlike 3.0

Skylarks are ground nesting birds, found mostly in farmland. A few years ago we visited Lundy, which seemed to be bursting with skylarks. Elsewhere in Britain skylarks are a rarer sight. Their numbers halved in the 1990s, and continue to decline.

The main reasons behind the plummet in skylark numbers seems to be changes in farming practices. The move from spring to winter sowing of crops, overgrazing and a shift from hay making to silage have dramatically reduced the habitat available for skylarks to breed in.

I missed skylarks on Box Hill because it felt like the right sort of habitat for them. But I think there was also a sub-conscious expectation that there would be skylarks there, because of its links to skylarks in poetry and literature.

The 19th century writer George Meredith lived on Box Hill, and wrote the poem The Lark Ascending that inspired one of my favourite pieces of English music, by Ralph Vaughan Williams. Vaughan Williams lived in Dorking, the town Box Hill protects and shelters. His The Lark Ascending is said to describe the English landscape in musical form, as well as capturing something of the soaring beauty of the lark’s song. While I love this piece, I hope it isn’t the closest our next generation gets to hearing skylarks.

Chalk grassland: Europe’s rainforest?

Sometimes places that look barren or dull can be full of diverse wildlife, on closer inspection. I am a bit of a tree fan, so it’s always been the woods of Box Hill, with their rare box trees, that have excited me. While the grassy slopes of the hill have appealed to me aesthetically, I assumed that the real wildlife was elsewhere.

The grassy slope to the summit of Box Hill

A recent walk up the hill on a sunny day made me suspect I might be wrong.  What, from afar, looks like boring old grass, is actually a huge variety of plant species, including many different flowers. And these plants were buzzing with insect life.

Chalk grasslands are home to a huge range of plant and insect species

A bit of reading up on the subject has confirmed that my earlier assumptions were well wide of the mark. Chalk grassland, grazed by sheep and unfertilised, is one of the UK’s richest for plant and insect diversity. The poor, thin soil, and regular grazing, means no single species can dominate.  A square metre of chalk grassland may have up to 40 different plant species, leading to some calling it Europe’s answer to the rainforest.

The chalk grassland slopes of Box Hill, looking towards the woods

This diversity of plants gives food and shelter to a wide range of insects.  41 different types of butterfly have been found on Box Hill, including some of the rarest in the UK. I didn’t even know there were that many butterfly species in Britain.

Chalk grassland is in itself quite rare. It is an internationally important habitat and is a priority in the UK Biodiversity Action Plan.Besides the North and South Downs there aren’t many other large areas of chalk grassland left. Much has been lost in the last 50 years due to changes in farming, (intensification including use of fertiliser and over grazing), encroachment of scrub where grassland isn’t grazed, and development of land for other purposes. Only 1% of the Surrey Hills has remnant chalk grassland cover.

Looking south from Box Hill

There’s been quite a lot of controversy locally about a recent Court of Appeal judgement allowing some chalk grassland to be turned into an exclusive golf club. Neatly manicured, fertilised and herbicided greens and fairways are deserts compared to natural chalk grassland.

While it may not have the immediate feel of the wild that you get in woods or at the coast, chalk grasslands are rich habitats, and need protection. Losing chalk grassland means losing a unique and fragile ecosystem, which we will be poorer without.

Looking from Box Hill towards Dorking