Let them dig ponds

Naturally enough, I wholeheartedly agree with Sir David Attenborough’s suggestion that, as well as going on a back garden safari, people ‘could dig ponds………………to encourage wildlife into gardens‘.

Practically Perfect Pinkhill



Pinkhill Meadow, Oxfordshire, from space: to the left is the R. Thames, to the right Farmoor Reservoir

During the last week I’ve made a couple of visits to ‘our’ Pinkhill Meadow nature reserve.

I say ‘our’ in inverted commas because actually it’s not ours, but is very much a joint venture between Thames Water, who own it,  the Environment Agency, who paid for most of it, and Pond Conservation. Our role was really to help with the design of the site, and oversee its construction – and it has since become our most important demonstration site.

Pinkhill is a set of ponds sandwiched between the Thames and Farmoor Reservoir, west of Oxford.

The ponds were made nearly 20 years ago now – and the site is important not only because it is a lovely place but because it is one of the most important demonstration sites for the principles of the Million Ponds Project – showing how making new clean water ponds in the landscape helps to protect freshwater wildlife more generally, not just the things that live in ponds.

Pinkhill is particularly important because, with funding from the Environment Agency, we have been able to carefully monitor the ponds as they have developed over the years – and it’s this monitoring which has revealed that 20% of all Britain’s freshwater wetland plants have been seen at this one location – all colonising naturally – and also 20% of the bigger freshwater invertebrates. They too have colonised entirely naturally.

Pinkhill is really the first place in Britain (perhaps the world) where a set of ponds and pools have been designed based on real knowledge of how ponds actually work, as opposed to the many myths that, until a few years ago, dominated approaches to pond creation.

I will return to some of these principles a little later.

For now its enough to know that I saw three Biodiversity Action Plan species that breed on the site: Common Toad, Reed Bunting and Grasshopper Warbler, as well as Cettis Warbler and a pair of Barn Owls. Many of the individual ponds – there are about 30 on the site: from one-third of a hectare down to a few square metres - are ‘priority ponds’ under the UK Biodiversity Action Plan because of their near natural state and the richness of their plant and animal communities.

Part of that natural richness is due to water beetles – and I also saw a nice range of these, which are some of my favourite animals, including this distinctive stripy beast which goes by the name of Hydaticus seminiger – it’s one of those animals that you are most likely to see in better quality ponds. Interestingly, I have had it visiting my garden pond.

Hydaticus seminiger: a distinctive diving beetle, found in better quality ponds. This picture is from Biopix in Denmark - if you need good freshwater invertebrate pictures for use in publications this is a good place to start, and their charges are very reasonable

I also found a few nice big things too –  including this splendid Water Stick Insect (you can see why I recommend Biopix compared to my efforts!).

A water stick insect in the hand is worth......

All of this life is packed into 2.5 hecatares – showing just what wildlife hot spots ponds can be.

But what’s perhaps most startling of all is that there are hardly any other places like this in Oxfordshire – there are a lot of nice ponds on and around Otmoor (especially on the old meadows that fringe the new RSPB reserve), and there are nice ponds at Little Wittenham Nature Reserve and at err, well…actually it’s hard to think of many places. There are the odd ones scattered about, but the truth is, concentrations of good quality ponds, like those at Pinkhill, which ought to be a commonplace, are remarkably rare.

Beautiful pictures (not here! At Frog End)

Take a look at Helen’s beautiful pictures of a Broad-bodied Chaser recently emerged from her garden pond at Frog End.

Here one of mine just to remind you quite how good Helen’s are!

Emerging Broad-bodied Chaser leaving the Old Pond in my garden

An exciting arrival in the garden

Ephemera danica - The Mayfly - lying spent on the pond

At the weekend I was very pleased to find a spent female of the mayfly Ephemera danica on the New Pond – this is The Mayfly.

The nearest stream is 250 m away, from where she most likely came. I am hoping that, presumably having been attracted to the gravelly substrate, she will have gone on to deposit her eggs in the pond.

The arrival of this animal is interesting for a couple of reasons.

First: The Mayfly is usually thought of as a classic lake or river creature. But its arrival at our little garden pond neatly exemplifies the rule that many animals thought of as exclusively riverine also turn up in ponds, sometimes more often than we imagine.

The three species of Ephemera found in Britain are amongst our biggest mayflies and a splendid sight during May as they emerge – mainly from from rivers, streams and lakes and sometimes bigger, usually gravelly, ponds. Two are common, The Mayfly and the Dark Mayfly, and one a rarity, Ephemera lineata -  I don’t think it yet has a formal English name but I’ll call it the Lined Mayfly.

In fact Ephemera danica is not often seen in ponds – we found it in just one river valley pond in Wales in a survey of 200 top quality ponds across the whole of Britain. The more pondy species is the Dark Mayfly (E. vulgata). As far as I know, the Lined Mayfly has not been recorded in ponds at all.

The second thing that’s interesting about the arrival of Ephemera danica in our pond is it illustrates how river animals don’t just fly up or downstream looking for new habitat: some also go sideways. It makes sense for a proportion to do this, to ensure that they don’t get stuck in one river or stream valley where conditions may become unsuitable. And if you’re going to go sideways, away from the river, you can imagine how it would also make sense (in evolutionary terms) to be able to survive not just in running water but also in ponds, either to provide a stepping-stone to a new river valley, or to allow for later recolonisation of the natal river, perhaps after some major disturbance – like a big flood or a severe drought.

We don’t know how often this happens – but if I can see it after just one year in our new pond, I don’t think it can be a terribly rare event.

Now I’m keeping my fingers crossed that there will be some babies – that would be exiting.

Dragonfly emergence

Broad-bodied Chaser dragonfly completng its emergence on low-growing grasses at the edge of the Old Pond

My Broad-bodied Chasers are emerging en-mass this morning: there are at least four coming out now as the day hots up.

There are something in the region of 50 in the pond – we know because we did a detailed survey last autumn, using the standard National Pond Survey 3 minute hand net sample method. In fact, amongst the Abingdon ponds we surveyed last year this was one of only two ponds with Broad-bodied Chasers, the other having just a single specimen.

But actually there’s nothing very unexpected in all of that – what is interesting about the picture above is where the dragonflies  are emerging.

On grasses – quite low growing, at the pond edge. The one above is quite happy using plain old creeping bent (Agrostis stolonifera).

It perhaps shouldn’t be a surprise that this plant is suitable for dragonfly emergence – it is the wetland plant seen growing around more UK ponds than any other.

It is almost never planted, and never knowingly sold by (virtually all) plant suppliers.

It’s a great pond plant.

Articulated rush

Articulated Rush: a good and little used edge plant, showing my usual planting method. Dump it on the waterline and wait for it to grow. No pots, no soil, just plants and water.

One plant which is a taking nicely at the edge of the New Pond is Articulated Rush (Juncus articulatus).

It’s not a plant that’s recommended often – possibly suppliers don’t really know it exists – although it is a common plant in real ponds.

It’s a good edge plant – quite low growing, more trailing into the water than most rushes (except the much more aquatic Bulbous Rush, Juncus bulbosus), at home on bare new sediments like clay, sand or gravel, and a good shelter for smaller animals amongst the submerged roots and leaves.

As per my normal approach, I just placed  a small clump roughly at the water line and let it sink or swim – no pots, no compost, just let the plant create its own anchor as its roots spread out and consolidate the thin layer of gravel.

Its doing fine, as the picture shows.

More fairy shrimps

Fairy Shrimp (Chirocephalus diaphanus). Photo: Jean-François Cart

I’ve received two more reports of Fairy Shrimps turning up, from pond enthusiasts Bev Wadge at Sussex Wildlife Trust and John Buckley at Amphibian and Reptile Conservation.

Bev has them in the Sussex Weald, near Chailey, and John in ponds close to spiritual the home of natural history, Selborne.

The latter is especially appropriate as the Earl of Selborne is Pond Conservation’s patron!

Any ponds with Fairy Shrimps are automatically classified as Priority Ponds under the UK Biodiversity Action Plan which means that everyone should be making special efforts to protect these sites – especially from water pollution and inappropriate management.

In this case ‘inappropriate management’ would include fish stocking or deepening which made the ponds permanent. Fairy shrimps are one of those creatures which depend on ponds that dry out and which cannot co-exist with fish.

Fairy Shrimps are protected on Schedule 5 of the Wildlife and Countryside Act which means it is an offence to disturb them in any way – including collecting them without license.

There are about 20 places where Fairy Shrimps are known in Britain with most being found on Salisbury Plain and in the New Forest.

Changing the subject slightly: Helen has some nice pics of recently emerging dragonflies and damselflies at Frog End.

Totally taken over by tadpoles (well, almost)

Dipping tray yesterday (14 May 2010): click for a closer view

I thought it was about time to dip the Old Pond to see how things are  going.

And its pretty clear that there are a lot of tadpoles – mostly rather small and growing rather slowly.

But lurking amongst the bucketloads of taddies I’m pleased to see:

• quite  lot of caddis flies – there are two kinds: the group known as the Cinnamon Sedges, and the swimming caddises known as Black Silverhorns (Mystacides azurea).
• plenty of Broad-bodied Chasers lurking amongst the moss (a couple can be seen in the photo – one nearly ready to emerge and one half grown) and Large Red Damselfly larvae (also in the pic) – and now we’ve had our first adult Large Red’s emerging as well
• plenty of my nice little Smooth Rams-horn snails.

But what was most interesting were some tiny darter dragonfly larvae – presumably quite recently hatched – probably Common Darters (Sympetrum striolatum)

So this means that the pond has more species of dragonfly than the average damaged countryside pond – though not more than an unpolluted countryside pond.

One difference between this year and last is I’m very short of Pond Olive mayfly larvae – this time last year there were hundreds but, perhaps because of competition with the tadpoles for food, they are much less common now. In fact after quite a bit of looking I haven’t found any yet.

Considering the abundance of food (tadpoles) there aren’t many backswimmers or beetles around to capitalise on the potential feast. Newts would have a field day, too, but so far we’re newtless.

Biodiversity crisis, what biodiversity crisis?

Last night we were part of the OPAL team that projected these giant frogs on an old power station in London.

Battersea Power Station - last night

But back in the real world, protecting biodiversity isn’t figuring anything like so large.

Below are the joint proposals of the new Conservative / Lib Dem coalition on the environment.

There is one important measure there on biodiversity which we hope will do a lot of good – and we’ll do our bit to contribute positively to its development. But there’s only one. To protect biodiversity properly there are plenty of other big threats that need to be addressed too – especially for the water environment, which is one of the most vulnerable parts of the natural world. Addressing these threats is in danger of disappearing from the agenda as climate, transport and energy become the only ‘environmental’ show show in town.

Here is the full text of the coalition agreement reached by the Conservatives and the Liberal Democrats

The parties agree to implement a full programme of measures to fulfil our joint ambitions for a low carbon and eco-friendly economy, including:

• The establishment of a smart grid and the roll-out of smart meters.
• The full establishment of feed-in tariff systems in electricity – as well as the maintenance of banded ROCs.
• Measures to promote a huge increase in energy from waste through anaerobic digestion.
• The creation of a green investment bank.
• The provision of home energy improvement paid for by the savings from lower energy bills.
• Retention of energy performance certificates while scrapping HIPs.
• Measures to encourage marine energy.
• The establishment of an emissions performance standard that will prevent coal-fired power stations being built unless they are equipped with sufficient CCS to meet the emissions performance standard.
• The establishment of a high-speed rail network.
• The cancellation of the third runway at Heathrow.
• The refusal of additional runways at Gatwick and Stansted.
• The replacement of the Air Passenger Duty with a per flight duty.
• The provision of a floor price for carbon, as well as efforts to persuade the EU to move towards full auctioning of ETS permits.
• Measures to make the import or possession of illegal timber a criminal offence.
• Measures to promote green spaces and wildlife corridors in order to halt the loss of habitats and restore biodiversity.
• Mandating a national recharging network for electric and plug-in hybrid vehicles.
• Continuation of the present Government’s proposals for public sector investment in CCS technology for four coal-fired power stations; and a specific commitment to reduce central government carbon emissions by 10 per cent within 12 months.

We are agreed that we would seek to increase the target for energy from renewable sources, subject to the advice of the Climate Change Committee.

Liberal Democrats have long opposed any new nuclear construction. Conservatives, by contrast, are committed to allowing the replacement of existing nuclear power stations provided they are subject to the normal planning process for major projects (under a new national planning statement) and provided also that they receive no public subsidy.

We have agreed a process that will allow Liberal Democrats to maintain their opposition to nuclear power while permitting the government to bring forward the national planning statement for ratification by Parliament so that new nuclear construction becomes possible.

This process will involve:

• the government completing the drafting of a national planning statement and putting it before Parliament;
• specific agreement that a Liberal Democrat spokesman will speak against the planning statement, but that Liberal Democrat MPs will abstain;
• and clarity that this will not be regarded as an issue of confidence.

Garden ponds ‘inadvertently polluted’

The Guardian and Telegraph today carrying reports of the early results of the Big Pond Dip – and leading on the fact that many ponds are polluted by tapwater.

See:

http://www.guardian.co.uk/environment/2010/may/09/ponds-polluted-tap-water

http://www.telegraph.co.uk/earth/wildlife/7703235/Tap-water-is-culprit-for-polluting-garden-ponds.html