Time for a Trim

Tuesday is one of our volunteer task days at Blashford and today’s task was to cut the vegetation in front of Ivy North hide and open up some sight lines through the reedbed. The hides are great for seeing birds but only if we can keep the views open, but more than this we are also trying to ensure that people get the best possible views of the wildlife that might be on offer. One of the occasional treats at Ivy North is the chance to see a bittern and this is one of the main objectives of the reed cutting near this hide.

Ivy North reeds before

Reeds at Ivy North hide before cutting sight lines.

The reeds have been spreading and this year’s growth was especially vigorous, meaning than cutting the line was hard work. The one positive was that it was fairly dry, although this made cutting easier to do it means that there is not likely to be a bittern there any time soon.

Ivy North reeds after

Ivy North reeds after cutting sight line

This year I also cut a line through to the water right in front of the hide.

Ivy North reeds centre area after

a line cut through to the water

The objective of a hide should be to give the observer a view that they would not get otherwise. At Blashford we have tried, as much as possible, to get each hide to deliver something different and hopefully at least one or two will have something really worth seeing from them at all times of the year. Today there were two peregrine near Tern hide, with one adult perched on one of the posts near the hide, the water pipit was seen from both Tern and Goosander hide and a great white egret from Ivy North, despite our  working outside the hide. The only other birds there whilst we were working were two or more water rail heard calling and a singing Cetti’s warbler.

We are soon looking to replace the Tern hide, it is in a very exposed location and is showing signs of age ahead of most of the others. Replacement offers the chance to tweak things a bit too and the new hide is to be slightly larges, slightly higher off the ground and moved ever so slightly, all changes that should give improved views. Expect to read more about this and other updates top the reserve in the coming weeks.

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How Wild Should We Go?

I was asked recently “Why can’t you just let nature be nature?” from which I understand the questioner meant, why do we do management on nature reserves? It is a very good question and one that is being directly addressed by a number of “Rewilding” projects at present.  As someone who is called upon to manage nature reserves I can say that I am always looking for the least intervention possible to retain the identified site interest. Where possible allowing natural succession to run the show is the preferable option.

So why do we do any site management at all? One obvious reason is that most reserves have visitors and they need to be kept safe, have usable access and something to see without compromising the wildlife interest of the site. On a site like Blashford Lakes these issues would probably be the main driver of most of the reserve management done by the staff and volunteers. Nature reserves are where people get a chance to engage with wildlife, where education about the natural world can take place and where we can just enjoy the natural world.

Beyond visitor safety and quality of experience the priorities start to get a bit more subjective. Thankfully the days of managing a site for a single species are largely gone, today nature reserves are about habitats and the suites of species that might live within them. There is no question that fashion has been as much a driver in nature conservation as in most other fields of human activity. Certain species or habitat types being flavour of the month (or perhaps decade) and much else that is truly wonderful getting sidelined.

So how do we decide what to, or if there is a need to do anything? The first thing is consider the data, see what is available, collate all the information we can find and identify the gaps in knowledge that need filling. At Blashford we knew the lakes were of international importance for wildfowl, so management for these species was going to be important. The lakes are a recently created habitat and are changing so we also need to keep an eye on how they are developing, where changes are outside practical management control  this needs to be recognised so that we achieve the most sustainable future of greatest benefit of wildlife. Since we have been running the reserve we have discovered a number of notable species including several new to the county and this information informs management, either indicating that something should be done, or not done.

Most nature reserves are not in a climax habitat state, that is if they are left alone they will not stay the same, this is called habitat succession. This may not matter, except that most reserves were established because they had interest for wildlife and change implies potential loss of this interest, even if it might also include the acquiring of new interest. Importantly nature reserves exist in a context, they are rarely large enough to support viable populations of many species, so the habitat of the wider area is also a vital consideration. One undesignated (i.e. not SSSI) part of Blashford Lakes is the lichen heath, it turns out that this probably home to more rare species than any other part of the site. It will  slowly turn into secondary birch woodland without intervention, so in this case there is probably a good case for trying to halt this successions and “reboot” the area to allow continuation of this habitat beyond its natural lifespan.

Our new reserve at Fishlake Meadows is a great example of how nature can reclaim an abandoned area. A natural looking wetland developed rapidly once the pumps that sustained conventional agriculture were turned off. The reserve is now one of a string of important wetlands along the Test Valley, from the brackish transition marshes of the Lower Test through the standing waters of Testwood Lakes and on up through the Broadlands Estate, the string continues north to Mottisfont and beyond and all linked by the River Test itself. It quickly developed into an area of pools with reedbeds and tall fen, plants that could colonise freely from the species rich habitats close by. The existing trees mostly died as their roots became waterlogged, but new trees came in, mainly willows, well adapted to wet conditions. The resulting mosaic of habitats attracted many species, including a number of scarcer ones. Surveys at this time showed just how diverse the site had quickly become, its potential for wildlife was clear, the task was how to secure the site as a long term haven.

Now that Fishlake Meadows is a reserve new surveys are being conducted. What was immediately clear was that the fen plant communities were more restricted and less diverse than they had been a few years before, this appeared to be because they vegetation was taller and dominated by fewer larger species. It was also clear that the willow scrub has turned into woodland in many areas shading out the vegetation underneath and was continuing to expand. Closed canopy willow woodland will develop quickly in reed swamps and fens if the water is not too deep and although good for some invertebrate species it is generally less diverse than the earlier successional habitats it replaces. It is also not a particularly rare habitat and can be found widely along the less managed parts of many of our river valleys. Fen grasslands are much rarer and as are many of the species that depend upon them.

It is reasonable to ask “Why intervene to try and keep short-lived habitats?” We could just step back and watch. It is also interesting to ask “How come these species that depend upon early successional stages are here at all?”. If we try to look back in time much of the country would have been covered in woodland, trees are the natural climax vegetation type for this part of the world. This cover would not have been continuous though, the landscape would have included large herbivores, such as wild cattle, wild boar and other species that would have changed the plant communities like beaver. These along with natural flood plains would have resulted in areas where trees were fewer, indeed beaver dams may well have had the same effect on trees in valleys that turning off the pumps had at Fishlake. These lost species would have prevented ares from achieving their potential climax vegetation type resulting in scrub, glades and perhaps extensive grasslands in suitable locations. Work at the Knepp Estate in Sussex is showing how having a range of large herbivores, in this case domestic animals that mimic the activity of wild species, produces a varied mosaic of habitats, very like that aimed or by most nature reserve managers. They maintain areas of early successional habitat without the need for constant intervention.

Many other valued early stage habitats are entirely man made, hayfields would be an example, even though the species could have survived in grazed grasslands they would not have achieved the densities experienced in managed hayfields. So sometimes we are managing to maintain historic land practices that happen to be good for wildlife, although they are not natural.

So we undertake management for people, in an attempt to mimic the likely impacts of  larger habitat changing species which we have now lost from our environment or to maintain historic human activities which have produced habitats which we deem to be of interest. The less work we have to physically do ourselves to achieve this the more land we can manage for wildlife. Low density grazing by hardy cattle breeds seems to be a fair substitute for the impact of wild herbivores, which is why the Trust has a herd of native breed cattle. If we can get the regime right the fen habitats at Fishlake should require very little intervention to be maintained, grazing will open up ares of shorter vegetation and reduce scrub invasion. Together with other areas where succession will continue this will hopefully maintain a complex and diverse habitat for many years to come.

How wild should we go? As wild as we can, if we allow space for nature it will thrive, but space is everywhere, if we confine nature to nature reserves many species will not survive. We need to remember that to survive a species needs continuity of the resources needed for survival. Maintaining habitat diversity is key to maintaining species diversity and the greatest range of resource continuities. Extinction is a once in a lifetime event best avoided or at least put off for as long as possible.

If we can start to set aside really large areas we might actually be able to step back entirely and let things go properly wild, but perhaps we are not yet ready for wild cattle, lynx, wolves and all the rest. We may like our wildlife, but not be ready for it to  be properly wild just yet. In the meantime we will have to manage habitats and continue in our roles as proxy aurochs and substitute beavers.

yellow loostrife bee

Yellow loosestrife bee, nectaring on creeping thistle. A species that depends upon lush, sunny, wet fen habitats.

 

In Between Times

A cold and frosty start to the day saw mist rising from the lakes as the sun came up.

ivy-lake

Ivy Lake, early morning

It was warm in the sun though and where it touched the frost disappeared quickly.

It might be “Christmas week” but as it was Thursday the volunteers were out in force to continue a willow cutting task in the reedbed area towards the Lapwing hide. This is a curious area of habitat, an old silt pond that filled with reeds and willows as it dried out. Normally the willows grow up and the reed dies off, here though, the willows are struggling and the reed seems to be doing better each year. The original plan was to manage it as willow scrub, but the willow refuses to grow and so we are opting for a reedbed with scattered willow instead. So we are cutting areas of the weak willow and allowing the reed space to expand.

volunteers-cutting-willows-in-the-reedbed

Ten volunteers turned out today to continue willow cutting in the reedbed.

We have also been cutting willows in the old silt pond near the Centre, although here they grow back vigorously. Our last task there was the Thursday before Christmas and despite the lure (?) of Christmas shopping there was a good turn out then too. We always try to make positive use of the cuttings where we can, today we were making a dead hedge which will probably grow up with brambles giving some valuable habitat. The dead twigs are also a valuable habitat in their own right, we are often told of the value of log piles for wildlife, but deadwood does not have to be large to be good for wildlife lots of species will use smaller deadwood.

The brash from the sallows near the Centre is being used to top the bank alongside the new path that is going in between the main car park and Goosander hide. I am hoping this bank will grow a bramble top which will provide cover for lots of species and nectar for insects and this will grow up in the shelter of the dead hedge.

the-source

The source coppice

the-destination

The destination

Although the weather has turned colder so far it has not resulted in much change in the wildlife on offer on the reserve. There still appear to be 2 great white egret about, the regular bird, “Walter” mainly around Ivy Lake and usually roosting there each evening and the newer arrival which seems to prefer the area from the north of Ibsley Water and off the reserve towards Mockbeggar Lake and Ibsley North lakes. A bittern is still being seen somewhat intermittently from Ivy North hide, where there are also water rail and Cetti’s warbler. At the Woodland hide up to 3 brambling are being seen as are a few reed bunting along with all the regular woodland species. Under the alder carr just outside the Woodland hide there was a water rail feeding in the open for most of today in the wet area just by the path, giving a great opportunity to see this usually shy bird well.

On Ibsley Water the gull roost is still as large as ever and includes 2 or 3 Mediterranean gull, 2 different ring-billed gull (although it is some days since both were seen on the same evening), 10 or more yellow-legged gull and a few gulls that remain a challenge to even the most dedicated. If you look at enough gulls you realise there are a few that just don’t “fit”, perhaps hybrids or birds of more distant and unfamiliar races or just plain oddities. A Bewick’s swan made an appearance late yesterday, although it did not seem to come to roost this evening, so has perhaps moved on. On the eastern shore of the lake this morning there were at least 8 raven attracted by some carrion on the bank. In the evening a small roost of starling behind the Lapwing hide have been trying their best to put on a bit of a show, but with only about 2000 birds it is not quite ready to rival Rome city centre. Two snipe were very obliging in front of Tern hide this afternoon and a green sandpiper always seems to be there just after dark as I hear it calling when I lock the car park.

Don’t forget the Pop-up Café returns to Blashford on New Year’s Day, so you can come and see some great birds and eat great cake too!

Potatoes and Pies

The Thursday volunteers were coppicing today and we took the opportunity of the fire we were using to burn up the top to bake some potatoes for our Christmas Bash. A tub of grated cheese, some butter and excellent chutney went well with what turned out to be perfectly cooked potatoes, we finished off with homemade mince pies.

p1060713

Lunch for the volunteers and Jim (who just came for lunch!)

The willow in this area grows poorly and often dies back, I think because of the poor soil which is derived from pumped silt. Reeds grow well though, especially where it lies wet in winter and I think this is what will happen once this area is cleared. This was our second day cutting and I expect it will take a couple more sessions to clear the whole patch.

finish

Still work to do, but we are getting there.

A day spent cutting willows meant that we saw almost no wildlife, a couple of egrets flew over, one was certainly a little, the other, spotted just as is went behind the trees looked like a great white. When I went up to turn in the fire as it got dark I also had a quick look from the Lapwing hide and there was certainly a great white egret there then, along with 90 goosander. We did find a winter moth in the willows and what looked like a butterfly flew off unidentified just before lunch. Otherwise a couple of calling chiffchaff were the other highlights.

Elsewhere on the reserve a brambling was reported by  a few visitors today, hopefully to be followed by many more.