Knepp cuckoos dust themselves down post-Sahara

Friday 18th May was a particularly exciting day for me, as Chris Hewson and Lee Barber from the British Trust for Ornithology (BTO) were visiting us for a very special reason...

The BTO have been studying the migration of cuckoos since 2011, fitting the larger male cuckoos with satellite tags to learn if their different migration routes can be linked to the decline in cuckoo numbers in the UK over the last 20 years. They have seen declines in Scotland and Wales, but the greatest has been in England: 68% decline in 25 years.

We're delighted, therefore, that at Knepp Wildland we are surrounded by that unmistakable call in the spring; we think their good numbers here may be linked to the abundance of dunnocks nesting in the heavy scrub and growing-out hedgerows as this is one of the species that the cuckoo will parasitise the nest of. It's tricky to estimate but we think we have six males that frequent the Wildland.

It was 04:15 and just getting light when we met - we had set up the kit the night before so we were ready to go at dawn. We unravelled the nets, set the cuckoo sound lure going and put the pièce de résistance in place: Madame Cuckoo, the cheeky temptress.

Chris Hewson (BTO) holding Madame Cuckoo

Within minutes there were two excited male cuckoos in the net! I was amazed at how quickly they responded. We were able to put BTO metal rings on each bird (each ring has a unique number), measure and weigh them, and then fit the satellite tags. It was fascinating watching Chris and Lee fitting such an intricate bit of kit to these cuckoos, knowing that the data that the tags would collect and regularly feed back could be crucial to help the conservation of this species. 

The satellite tags amazingly weigh less that 5g (that's the same as a sheet of A4 paper) - this allows birds as light as 100g to be tracked. The tag has a solar panel that allows a smaller battery to constantly recharge.

Raymond the Cuckoo with satellite-tag fitted

Two more cuckoos were caught later on that morning, this time one female and one male. So both were ringed, and a tag attached to the male. The three tagged cuckoos were named Knepp, Raymond and Lambert. The names are family names: ‘Raymond’ is after Charlie’s father, and ‘Lambert’ after Issy's.

Lee Barber (BTO) and Raymond the Cuckoo with his satellite-tag

Since these cuckoos were tagged back in May they, along with nine other cuckoos, have undertaken the most amazing journey south to central Africa. Forty two cuckoos have previously been followed by the BTO on this journey and from this research it has been discovered that cuckoos take one of two routes: southwest via Spain and Morocco (the ‘west route’) or southeast via Italy or the Balkans (the ‘east route’) before converging in the Congo basin of central Africa. Birds taking the west route are more likely to die before completing the Sahara crossing (more details about this on the BTO website) so imagine our horror, then, when we see that all three Knepp birds are heading off on the west route!

Here are the routes, from left to right: Knepp, Raymond and Lambert.
(Please note that the aberrant track shown for Lambert may be due to a fault in satellite readings).

There were a few hairy moments for us as we waited for news of their progress - but we were so pleased to see yesterday that Raymond had made is safely across the desert - he was the last of this year's cuckoo cohort to make it across...Phew! 

Knepp has settled in Burkina Faso, joining four other tagged cuckoos.

Raymond is currently on the eastern edge of the Reserve de Faune du Ferlo Nord in Senegal.

Lambert is in Senegal and the BTO say "He is the furthest west we have seen any of our cuckoos."

Amazingly all the BTO tagged cuckoos have survived their perilous Sahara crossing. Now we anxiously wait to see if they survive the season in Africa and if Knepp, Raymond and Lambert make it back all the way to Sussex next spring….

Do keep track of the BTO cuckoos on their website; any donations towards this research is most welcome by the BTO. A sustainable solar company Sussex Solar, based close to Knepp Wildland, has very generously sponsored 'Knepp' the cuckoo and are coming on safari in spring 2019 to enjoy the call that we're already looking forward to hearing again.

Many thanks go to Chris and Lee from the BTO, and to the 'Cuckoo King' Tony Davis for making this happen.

by Penny Green, Knepp Ecologist

A longhorn in the office

Luckily for us it wasn't one of our English longhorn cows that was found sitting on my boss's desk, but this stunning red Welsh oak longhorn beetle Pyrrhidium sanguineum.

This species was first found at Knepp in 2013 during one of our recording weekends, in a log pile at the bothy. This was only the second time it had been recorded in Sussex (the first time was in 2012). Since its first discovery at Knepp it has been recorded on four more occasions here.

This beetle is expanding its range from the Welsh borders, with most records in the southern half of the UK. The larvae feed under the bark of dead branches, stumps and logs of deciduous trees, mostly oak, and is often found in log piles. There's a small pile of logs from one of the estate's woodland in the office and as it's an unusual date for this beetle to have emerged (usually it is recorded from April to June) I imagine it's been fooled in to thinking it's a different time of year.

In the UK it is a rare species: it is an RDB2 species, which means its status is 'vulnerable'. 

by Penny Green, Knepp Ecologist

Is it safe to go in the water?

There's a great white at large!

The water in the tributary of the River Adur isn't quite deep enough to host a great white shark, but we've been thrilled to see a great white egret spending some time at Knepp. 

This magnificent bird has been spotted at Arundel WWT Reserve, Warnham Nature Reserve and Pulborough Brooks RSPB Nature Reserve - it may well be the same individual that has been visiting Knepp; it's not far to travel for bird with a wingspan of 170cm.

This photo was taken by Knepp bird survey volunteers Chris and Juliet Moore

Standing as tall as a Grey Heron, it's an impressive bird, with a pure white plumage and a pumpkin orange bill. As it prefers to hunt in flood meadows and along rivers where it catches fish, frogs and aquatic insects, the river restoration with its scrapes and slow flow is the perfect spot for feeding here.

In the last 25 years sightings of the great white egret have become more frequent in the UK, as their numbers grow in France and the Netherlands. In 2012 a pair successfully bred in the UK for the first time, and in 2017 twenty young fledged from two sites in the UK.

It's wonderful to see a bird that once saw such a catastrophic decline in Europe, thriving and expanding its range across Europe and here in the UK.

by Penny Green, Knepp Ecologist

Eats shoots and leaves

We're in the middle of the dramatic deer rut season here at Knepp Wildland, with the red deer having just reached their grande finale and the fallow well into the swing of it. The damp autumn air is charged with their primeval roars and belches, and the not entirely unpleasant stench of pheromones.

What great timing, then, that BBC's Countryfile team, with presenter Adam Henson, visited us a couple of weeks ago to film the rewilding project and were able to get some lovely footage of red stags battling for supremacy in one of Knepp's laggs, or water meadows.

The Countryfile programme is due to be aired on 19th November 2017 - so do tune in to hear Charlie Burrell discussing the rewilding project and how it all began, Isabella Tree talking about our wildlife safaris and engaging the public, our stockman Patrick Toe introducing our longhorn cattle, and Penny Green explaining the wildlife monitoring side of things.

A handsome red deer stag

The fallow and red deer are important agents in the rewilding project here at Knepp. Along with the our other free-roaming herbivores - Tamworth pigs, Exmoor ponies and Old English longhorn cattle - they are creators of habitat. 

Browsing red deer in a scrape

Their different grazing techniques - the way their mouths work, what they like to eat - has an enormous effect on vegetation. The way they physically disturb the land, too – from trampling and puddling, rolling and rubbing, snapping branches with their antlers and de-barking trees in winter – together with their ability to transfer nutrients and disperse seeds over wide areas, stimulate opportunities for plants and shrubs. Together with the other herbivores, they create an ever-shifting mosaic, a kaleidoscope if you like, of complex habitats - the transient, messy margins in which life thrives.

We're not a target-led project like most conservation programmes. We don't have set objectives or particular species that we're aiming to sustain; we simply allow the herbivores free rein and see what comes. The results have been spectacular. Incredibly rare species, like nightingales, turtle doves, Bechstein's bats, lesser-spotted woodpeckers, purple emperor butterflies, and peregrine falcons are now breeding here. More common species are rocketing, too - all of them following in the slipstream of our free-roaming herbivores.

A longhorn cow feeding on Sallow

Of course, we do manage the project in one crucial respect - the numbers of animals we have here. Too few, and the land would soon revert to species-poor closed canopy woodland; too many and the land would be overgrazed, reducing habitat for other species. It's this constant battle between vegetation succession and animal disturbance that creates the dynamism, and that we seek to maintain with the balance of numbers.

So, every year, we cull a certain number of animals to keep herbivore populations in check. This produces a vital source of income for the estate. Our organic, pasture-fed Knepp Wild Range meat is much in demand amongst restaurateurs, food connoisseurs and the health conscious. Animals that have access to an entirely natural diet and are free to choose when, where and what they eat, are not only happier and healthier in themselves, they produce meat and fat that is positively good for humans - a stark contrast to the meat, fats and dairy products produced in intensive systems from animals fed artificially on grain and performance feeds.

You can buy Knepp Wild Range meat in our farm shop, which is open until the end of October. It will open again, at the start of our Safari season, at Easter 2018.

If you've missed out on this year's Deer Rut Safaris, the 2018 safari calendar is already available for booking on our Knepp Safaris website.

Leaf it alone

It's been great weather for moth trapping, and with National Moth Night over the weekend I thought I'd share some of the lovely moths that we've caught here at Knepp Wildland recently.

At this time of year the moths are beautiful autumnal hues of yellows, pinks, oranges and browns - lovely for us to look at, but for them it's a survival strategy.

This Angles Shades is well-camouflaged as it looks like a dead leaf

The Sallow moth looking pretty similar to the leaf of it's namesake tree in the autumn

As moths rest up during the day, in trees and bushes, it's a time when they're quite vulnerable, so what better way to evade predation than to blend in with the surroundings? Looking at these photos it's clear to see what they all look like: leaves!

A Frosted Orange blending in with the autumn colours

The quirky-looking September Thorn looking like a raggedy leaf

The exquisitally iridescent Burnished Brass 

Other moths have warning colouration, like this huge Red Underwing: it has cryptic colours when at rest but if disturbed by a predator it flashes a red petticoat to startle and deter.

A Red Underwing showing a cheeky flash of red

by Penny Green, Knepp Ecologist

A Bird in the Hand...

Over one million birds were ringed by British Trust for Ornithology (BTO) volunteers in Britain and Ireland in 2016. Ringing helps us understand more about birds: about why populations are changing, where different species spend their breeding seasons and where they spend their winters, when they migrate and how long they live.

Here at Knepp Wildland we’ve been ringing since 2015; as well as contributing to BTO’s important research it’s also a way of learning which species are utilising the scrub. In the autumn/winter we catch Redwing that roost in the scrub and feed up on the berries, in the spring we concentrate on nest finding so we can monitor the success rates of different species, and also ring chicks in the nest such as these Dunnocks:

Then come late summer/autumn we’re catching birds in mist nets - picking up birds on migration that are feeding up on the fruits and the insects in the scrub – lots of Blackcaps, Whitethroats, Chiffchaffs, Willow Warblers and Reed Warblers.

The other day we received an email to say that a bird ringed at Knepp on 5th August had been caught somewhere else. It was a juvenile Reed Warbler:

photo: Sophie Trice/Tony Davis

Amazingly, just 16 days after being ringed at Knepp it was caught in Noain, Navarra, Spain…918km away! The Google map below shows the distance between Knepp and Noain:

We don’t know when it started its migration but it’s just fascinating that a bird weighing 11.5g (when we ringed it) made this long journey south within a couple of weeks of being at Knepp. Looking back through the BTO’s ringing recoveries I spotted a Reed Warbler that was also ringed in Sussex on 08/09/2016 and then recovered in Noain just 3 days later!

Huge thanks go to Tony Davis, our bird ringing trainer, for all his mentoring and support.

by Penny Green, Knepp Ecologist

Holy Cow, Batman!

Knepp Wildland hosts 13 of the 17 resident species of bat found in the UK – some have roosts here and some commute in from surrounding areas to feed on the flourishing insects.

At the beginning of the project, in 2001, only five different species had been recorded here but since then the restored waterways, growing-out hedgerows and insect-rich pastures have provided perfect feeding grounds. As a result of this the bat species list has grown.

One study showed radio-tagged female Barbastelles commute from their nursery roosts in The Mens Sussex Wildlife Trust reserve (near Petworth) - 18km away - to forage over Knepp Wildland.

On a recent Knepp Bat and Moth Safari we were able to meet up with batman Martyn Cooke, and his band of volunteers, doing a bat survey around the Hammer Pond. On this occasion, three species of bat were caught: Soprano Pipistrelle, Bechstein’s Bat and Whiskered Bat.

The Whiskered Bat feeds on a variety of insects, such as moths, so they are particularly susceptible to pesticides. Pesticides are no longer used here at Knepp, since the move from intensive agriculture, so there is a plentiful supply of food for them.

Whiskered Bat at Knepp - photo by Ryan Greaves

Surveys at Knepp in 2009 indicated that Bechstein’s Bat were breeding here, a very exciting find as this species is one of the UK’s rarest and most endangered bat species. It has extra protection under Annex II of the European Habitats Directive.

Bechstein's Bat at Knepp - photo by Ryan Greaves

Bechstein's Bats feed on small invertebrates, such as small moths. A dropping analysis in nearby counties showed a penchant for grasshoppers and dung-flies. We have plenty of dung-flies at Knepp on the Longhorn cattle dung: no ivermectins going in to the cattle means droppings full of delicious dung-flies and other insects that bats, birds and other wildlife can feed on.

Come along on one of our Bat and Moth Safaris to learn more about the bats of Knepp.

by Penny Green, Knepp Ecologist

Rush Hour

The Rush Wainscot is a Red Data Book moth, which is confined to just five areas in the UK. West Sussex is one of those areas with a couple of hotspots around the Horsham area. Its larval foodplants are Common Club-rush, Yellow Iris, Bulrush and Lesser Bulrush, of which we have plenty here at Knepp Millpond.

It was hunted for and not found in surveys during 1995. During baseline surveys for the rewilding project in 2005 it was targeted again, and this time one was discovered. It was caught in a moth trap on Knepp Millpond, but despite further attempts to catch this moth in following years it was not found again, this included several fruitless attempts in 2015 and 2016.

Always up for a challenge we thought we’d target another part of the estate this year, so we put moth traps out after our August Bat and Moth Safari, at the western end of the Hammer Pond. The habitat here is wonderful and just right for the Rush Wainscot.

We sorted through the moth trap at about 1.00am as we were planning on packing up: at this time the temperature had dropped and the moths had started slowing down. There was a good variety of different moths, with the autumnal-looking Dusky Thorn being one of the most numerous:

And we caught this unusual form of Clouded Border:

We had got to the bottom of the last trap...as we turned over the last egg carton we spotted something that looked pretty good to us. At last, a Rush Wainscot!

We're really pleased that it's still at Knepp; we won’t give up looking for it again at the Millpond though, it would be good to know that it’s still there too.

by Penny Green, Knepp Ecologist

Electric Eels

The Environment Agency (EA) carried out a river restoration at Knepp in 2011. Since then we've been collecting data to see how the river develops and what wildlife moves in.

This week Gareth and Damon from the EA did a fish survey along the southern part of the river restoration. They used a technique called electrofishing - this temporarily stuns the fish in order to be able to catch them and identify them. Here's Gareth looking like a Ghostbuster:

There's something about fish that brings out your inner-child...so I excitedly had my head in the bucket examining the first few net loads as they came out: Roach, Eel (I love seeing Eels, such a rarity now), Stone Loach, Three-spined Stickleback, and this beautiful Perch:

Then came Gudgeon, Chub, Dace, and this young Pike:

And this has got to be my favourite, the Bullhead:

Once the fish had been identified and measured they were put back in to the river:

Ten species was a really respectable total for a river in its early days of recovery. It was good to see fish of different ages using the river too, with young fish sheltering in the nooks and crannies provided by the coarse woody debris.

The hope is that as the river settles down and the bank-side vegetation becomes more established we will see an increase in biodiversity. With this in mind we will continue our surveys on the river and surrounding floodplain scrapes to see what fish, plants, snails, beetles and dragonflies move in over the years to come.

by Penny Green, Knepp Ecologist

Rewilding Britain: Planning, Policy and Practice

12 sept 2017

Rewilding aims to restore natural ecosystems using keystone species in a way that benefits wildlife and people. Can rewilding really be win-win for wildlife and landowners? What are the practical, political and economic risks? How can it be planned and implemented to maximise the benefits? These questions and more will be tackled during a one day conference jointly hosted by the Durrell Institute of Conservation and Ecology (DICE) and Wildwood Trust on Tuesday 12th September, 2017.

Do come to this conference at the University of Kent. Charlie will be speaking.