Chough report: July 2019

A chough family out and about at Grosnez. Photo by Mick Dryden.

By Liz Corry

The choughlets finally made it across to Sorel this month to join the flock at the supplemental feed. Some are flying further afield following their parents to the west coast.  They now face the same challenges life throws at all choughs; finding food, avoiding predators, and putting up with those pesky folk who keep wanting to put leg rings on them.

Attendance records at Sorel on the rise.

The choughs are finding plenty to eat around Mourier Valley. Photo by Liz Corry.

With nest sites vacated for another year, the adults are spending more time together at Sorel. The addition of hungry mouths to feed has seen attendance records at the supplemental feeds increase. It has allowed us to get a better understanding of total population size. More on that later.

This year sixteen choughs fledged from various nest sites at Sorel and Plémont. Sadly, as reported last month, three died within a week of fledging all injury related. That still leaves thirteen hungry mouths to feed.

It has been quieter this year at Sorel compared to 2018. The broods fledged at different times. Families were arriving at Sorel days, sometimes weeks, apart giving the youngsters time to adjust. Last year they all fledged within a relatively close time frame. I guess it was noisy because the chicks had to compete with each other for attention.

The surprising news came from Skywalker and Pyrrho who casually rocked up to the supplemental feed one afternoon with two chicks in tow. Quarry staff thought this nest had failed. As first time parents, we had also written off the clutch. Wrong! One of the few times you are happy to be proven wrong.

Earl of Plémont  returns triumphant

Rather a grand title yet justified for the next snippet of news. Earl and Xaviour are returning to Sorel for supplemental food. And so is their chick! On 4th July I found 40 choughs waiting for me near the aviary. As I started going through the roll call, I stared down to find two familiar faces (well leg ring combos) staring back. 

Earl and Xaviour (middle two) returned to Sorel this month along with their new chick. Photo by Liz Corry.

I had to work my way through the flock to finally discover which, if any, was their chick. It was positioned at the back of the group, silently getting on with life, foraging for food.

The Plémont chick getting down to business. Photo by Liz Corry.

We expected the family to make an appearance at some point; the hot dry summer has hardened off the soil making it impossible to extract insects. Their reliance on the supplemental feed naturally increases at this time. We have also learnt that the cows grazing at Les Landes, a chough favourite, have been removed due to the farmer having to make cut backs. These provided another source of food for the birds especially Earl and his family at neighbouring Plémont. 

Falling foul-can

Work with me on this pun as I’m trying to make light of a tragedy. One of Jerseys licensed ringers, Ian Buxton, contacted me this month with regards to a specimen submitted to the Société Jersiaise. Somebody found the remains of a bird whilst out on the cliffs around Sorel Point. On seeing an address stamped on the metal leg ring they thoughtfully bagged the remains and took them to the museum.

This is how Ian became involved and then sent me the following image…

The remains of chough PP036 hatched this year at Ronez. Photo by Liz Corry.

The legs belong(ed) to one of this year’s chicks – PP036 also known as ‘White over Cerise’. 

A peregrine falcon hanging out at Sorel Point. Photo by Liz Corry.

We do like to wind up our vets at Durrell, but I wasn’t about to submit this for a post-mortem. It is quite likely that the youngster fell foul to the resident peregrine falcon.

PP036 had been absent from the feeds since 13th July and discovered on the 17th. We have three more youngsters on our watchlist who haven’t been seen in awhile. They could simply be with their parents over at Les Landes or Crabbé. Although the recovered legs makes me suspicious.

I have contacted the Jersey Climbing Club to ask members to keep an eye out whilst dangling from granite. They are more likely to come across remains than we are.

Big catch up

To ensure each chough has a unique ring combination we had to plan several catches this month. As well as some unplanned, carpe diem moments. Four broods remained unringed and several adults had lost one or more plastic ring.

Making use of the overgrown bracken to operate the hatches. Photo by Liz Corry.

The parents of the unringed chicks were understandably protective. They were on the alert whenever we called the group over for food in the aviary. Often they would land on top of the netting and just stare at us until we gave in and left. If they did go inside, they would immediately fly out as soon as one of us merely thought about closing the hatches! 

The added complication was trying to time it when enough staff were available to help out. We only needed certain individuals from a group of potentially 48 birds. Trying to hand net and process that many in a confined space is stressful to the birds. You want to be able to minimise time spent inside.

On the odd occasion the youngsters were helpful. I would arrive to find one or two chicks already inside. In their naivety and panic, they would forget how to fly out of the hatches giving me enough time to reach the handles and close them.

 

The big catch-up came on 19th July when I managed to lock in 34 choughs. Three escaped the hatches in an Indiana Jones style – one of which was an unringed chick. We’ll gloss over that. With the help of a volunteer and a licensed ringer, I hand-netted 28 of the birds, we weighed them, and fitted or replaced leg rings as necessary. All birds were released back into the wild once we had processed them. 

Whilst in the hand, we discovered one of this year’s youngsters had a clump of matted feathers around the neck. It was dried blood. There was no obvious wound, no fresh bleeding, but clearly something had happened since it’s first catch up three weeks ago. One to keep an eye on.

In Memoriam

The big catch up and recent numbers at the feeds are evidence to suggest we have lost eleven choughs since January of this year. This is not including the deceased fledged chicks.

We know the reason for one bird was aspergillosis because we had a body to post-mortem. Around two thirds of the lost birds were in pairs. Their partners have re-paired with a younger male or female. Was that before or after the disappearance? Cue the EastEnders theme tune.

Name Age (years) Captive or Wild-hatched? Year released*
Mauve 7 captive-bred 2013
White 5 captive-bred 2014
Bean 5 captive-bred 2014
Helier 5 captive-bred 2014
Mary 4 captive-bred 2015
Q 4 captive-bred 2015
Ube 3 captive-bred 2016
Duke 3 captive-bred 2016
Lil’Wheezy 2 wild-hatched 2017
Clem <1 wild-hatched 2018
Bumble <1 wild-hatched 2018
* if wild-hatched this is year it fledged.

 

Bracken bashing for charity

Whilst the sheep do a grand job of grazing the National Trust land at Le Don Paton they have their limits. They don’t actually eat the bracken, certainly not in any quantities to make a difference. At least once a year the rangers take a tractor up to clear certain areas. Understandably, the slopes of Mourier Valley aren’t practical even for the most skilled of drivers.

A Manx loaghtan sheep grazing in Mourier Valley. Photo by Liz Corry.

The wonderful staff at HSBC rose to the challenge and volunteered their time to bash some bracken. Despite July’s scorching temperatures the team joined the National Trust’s rangers and did a great job and clearing the vegetation.

HSBC volunteers helping clear the bracken in Mourier Valley. Photo by National Trust for Jersey.

The sheep can now take over and make sure it stays low. This is how it would have been centuries ago when farmers kept livestock around the coast. Although I assume with less corporate branding. HSBC also helped the rangers at woodland on Mont Fallu and clearing the alien invasive succulent, purple dew plant, from the salt marsh habitat of St Ouen’s Bay coastal strip.

 

Chough report: May 2019

Breeding success for 2019

At the start of May, Toby Cabaret and myself carried out the first nest check in the quarry. It took a lot longer than last year (4 hour). Along with more nests to check there was a small addition of a film crew.

Action man Toby being filmed for a documentary. Photo by Liz Corry.

Tune in around autumn to hear more about that. Back to the nests…

We recorded eleven potential nests including one new location thanks to Kevin at Ronez who had been keeping an eye on a pair. He is also the ‘guardian’ of Red and Dingle’s building and has successfully convinced them to use the nest-box rather than the hot pipes. The negotiations have paid off – two chicks were visible in the nest on 23rd May!

Chough chicks, only a few days old, in a quarry nest box. Photo by Toby Cabaret.

PS. the camera in the photo has been knocked out of position by the parents so we can’t monitor remotely. The box was accessed at a predetermined time under licence. These chicks were too young to ring this month. We will return in June.

Quarry staff also confirmed Dusty and Chickay’s nest had hatched and that Green and Black looked to be feeding chicks. The former cannot be accessed without some dodgy ladder work. We have to wait to see what will fledge. Green and Black’s nest can be accessed only if you have a hydraulic crane and Ronez generously paid to hire one as there are several nests that require it. On 25th May Operation Test-out-Toby’s-crane-driving-skills was carried out. 

Kevin and new partner Wally (he must have a thing for hand-reared birds) have chicks. Her nest is one of the easiest to access and with the aid of a smartphone easy to check too…

Operation Test-out-Toby’s-crane-driving-skills

We checked Green and Black’s nest first; 3 chicks! They looked about four weeks old. We decided it would be too intrusive to fit leg rings as they could prematurely jump to their death if disturbed so we backed down (literally in the crane). Mum and Dad were watching over us and went straight in to feed them once we left.

Lee and Caûvette’s nest also contained three chicks. Toby managed to manoeuvre the crane tantalisingly close to the nest, but we were short by a few inches. My finger tips could just about touch the base of the nest if I stretched and leaned out of the cart. Actually removing a chick safely from the nest (not dropping it onto the rock pile 20ft below) was out of the question.

A frustrated Toby drove on to the next site. This time with more success. We checked the nest site belonging to Trevor and Noir. Last year they raised one chick but it failed to fledge successfully. This year they had three chicks in the nest. Licensed ringer Dave Buxton and trainee ringer Paul Pestana helped process the chicks with leg rings, biometric measurements, and DNA sexing. Hopefully all three chicks will fledge in a few weeks time.

Licensed ringer Dave Buxton training Paul Pestana to ring a chough chick. Photo by Liz Corry.

An exciting discovery at the start of May was finding out who was responsible for the ‘Mill nest’. We watched as Percy flew to the top of the external nest-box and fed a demanding Icho who had been waiting patiently inside. When he left, she went back inside the nest and we could hear chick begging noises. Toby had reported hearing chick noises previously, this visit appeared to confirm it.

On the 25th, with the assistance of the crane we went to access the nest to ring the chicks. This was the last nest to be checked that day and had been surprisingly quiet. As we slowly rose closer to the nest  entrance the only sound to be heard was that of the crane’s motor. Looking inside all we found were three cold, unhatched eggs. The nest had failed and the parents had abandoned.

A check of Percy and Icho’s nest found the chick to be missing and the remaining eggs had not hatched. Photo by Liz Corry.

I can’t end this section without talking about Tony’s mad crane skillz (with a ‘z’ like all the cool kids, sorry kidz). We wanted to check the building Kevin had been keeping an eye on. The day before Operation Test-out-Toby’s-crane-driving-skills (sorry skillz), Toby had spotted where the nest was located inside the building. Accessing it definitely required the crane. The trouble was how do we get the crane to the site with the various gangways and structures in the way. With mere millimetres to spare Toby drove the crane through the obstacle course and started taking us up. Removing the chicks from the nest safely was questionable as it required a fair bit of stretching. However, the dilemma was solved by taking a photo of the nest – the chicks were way too young to fit leg rings. And Toby had to tackle the obstacle course once again, this time in reverse!

The people on the ground managed to get a good glimpse of the leg rings on one of the parents. It was Pyrrho. We believe she is partnered with Skywalker. We give them another four weeks or so to see what leaves the nest. May the force be with them!

The Plémont family

There have not been many opportunities to monitor the Plémont nest. What we have seen has all been positive. Paul Pestana has kindly volunteered his free afternoons to keep an eye on them and has experienced a few cherished moments. Like watching Earl remove a faecal sac from the nest. To some, gross. To others, a happy sign that there must be a chick in the nest to produce the faeces in the first place!

Typical habitat to the east of Plémont – home to a pair of choughs. Photo by Liz Corry.

As the days passed and the chick(s) got older you could hear begging noises coming from the cliffs. Only of course if there was little to no wind and you were prepared to get perilously close to a cliff edge. By the end of May this nest was not far from fledging. If and when they do, we will need to monitor the site as closely as possible. The headland is accessible by the public who may pose a threat to bumbling fledglings, the nesting peregrine pair certainly pose a threat, and the steep plummeting drop to the rocky seas below…well that is all part and parcel of being a chough!

Catch-ups at the aviary

There have been several catch-ups at the aviary this month mainly due to health reasons. Two of the breeding females, Caûvette and Wally, managed to get their hind toes caught in their plastic leg rings. As has become the norm, it took a few attempts to get each female. Luckily no injuries had been sustained making it a simple case of unhook toe, refit ring, and release bird.

Wally was one of two adults needing to be caught this month to free their hind digit caught in their leg ring. Photo by Liz Corry.

Chewbacca was also looked at in the hand after presenting signs of lameness and general lethargy. Clinical diagnosis – attention seeking. That may be an unfair assumption he could have just been run down. Although the ‘lameness’ suspiciously swapped each day between left and right. Personally, it looked more like he was playing the ‘oh woe is me card’ at the supplemental feed resulting in more food being thrown his way. Remind me again, is it the choughs that are trained or the keepers?

Zoo chicks

Tristan and Penny’s eggs hatched at the start of May. As with all corvids it can take a day or two between eggs, so keepers had to wait a week before knowing how many chicks would hatch. Only one egg didn’t make it, leaving the parents with three hungry mouths to feed.

Everything was going well, both parents very attentive, until one day Tristan turned. Keepers watching the nest-camera footage could see that one of the chicks had died. Mum carried on feeding the remaining two chicks with the dead one left in the nest. Tristan started being aggressive towards Penny each time he returned to the nest to the point he was endangering both chicks and mum.

Keepers caught up Tristan and moved him to a separate aviary. They discovered he weighed 400g. Considering captive males normally weigh around 350g this may have been a clue to why he was behaving as he was. With some species, if the male takes on too much protein during the nesting season they become ‘randy’ for want of a better word. Eager to keep breeding even when the female has chicks which results in aggression often directed at the female and/or chicks. He might have been trying to tell Penny to get rid of the dead chick. We will never really know. Keepers are always trying to second guess their animals acting as chef, interior designer, GP, and psychologist on a daily basis.

Continued work at the aviary

The boring stuff – there are still several jobs that need to be done at the aviary. Net trimming, replacing rodent-proof mesh around doors and hatch frames, and replacing the fixtures removed when the old timber was ripped out. A lot of these require working at height with power tools therefore a second person and special ladders are essential for health and safety. By the end of May these jobs were still outstanding as it has been difficult to fulfil the H&S requirements.

Not helped by the additional job of net repairs. Deja vu? Yes, rodents have chewed holes in the brand-new netting. Apologies for any walkers at Sorel and beyond who heard my cursing that day. In just one night, eighteen small holes were chewed into the new netting along the north facing side of the tunnel. Whilst waiting for the guttering to be transported back up to the aviary another two holes appeared overnight on the other side of the tunnel. The guttering, unsightly as it is, is now back on preventing the rodents from reaching the netting from the outside. There is also a large hole in the middle partition at ground level. I suspect a rodent had become trapped inside the aviary when the rebuild happened and chewed their way out.

It is getting harder to capture the entire flock in one shot these days – a sure sign of success. Photo by Liz Corry.

Volunteer request

An advert went out asking for a volunteer to help with the gardening at the aviary. During the spring and summer months the grass in and around the aviary needs cutting on a weekly basis.

The bank around the perimeter also needs maintaining for the benefit of the wildlife and to keep the path for staff accessible. There is a considerable drop on one side that becomes hidden when the bracken grows up. One step the wrong way and it’s an undignified fall into bramble and blackthorn.

Volunteer needed for vegetation clearance at aviary. Sheep need not apply. Photo by Liz Corry.

Despite hay fever allergies I enjoy this job, but it does demand time and with no student placement this year I am finding it hard to keep on top of it. Several people have shown interest in the position, few can commit on a regular basis. Hopefully by June we will have found a suitable volunteer.

Private donors

We are very grateful to the De Lancey Foundation who gave a generous donation towards the running of the chough project. In return, a group from their board of trustees had a private tour of Sorel and our facilities. Their passion for conservation and knowledge on the subject was evident as we discussed the challenges faced and the achievements made to date. The Foundation is also supporting the head-starting of Jersey’s agile frogs at the Zoo.

Last but not least

A colleague took his young family to Sorel to see the choughs and Manx loaghtans. His son, a huge fan of the computer game Minecraft (no me neither), was inspired to create his very own red-billed chough character for the game. I think this has to be a world first! Well done Sam. Watch this space for the development of more Birds On The Edge characters.

A Minecraft chough created by Sam Wright after his visit to Sorel.

 

 

Chough report: June 2019

Plémont bay – a new territory for the choughs. Photo by Liz Corry.

By Liz Corry

A lot of ups and downs this month for the Channel Island choughs; literally in some cases! The nests have fledged with some surprising outcomes. Whilst the chicks were escaping their nests, I escaped the Island to Slovenia to talk all about choughs to Germans. 

Rewilding Plémont

In a first, on record, a wild-hatched chough has fledged at Plémont! The pair responsible were on their second season of trying and are the first to successfully breed away from Sorel.

The success is largely due to the pair’s ability to find food in the wild. They have not been seen at the supplemental feeds for a long time implying they don’t need it. Instead they forage around Plémont, Grosnez, and Les Landes. 

Research by BirdWatch Ireland showed choughs in Donegal have a preference of wind-swept, maritime grassland within a 1 km range from the nest. Petit Plémont headland matches this description perfectly. In addition, the wonderful restoration work of the derelict Pontins site by the National Trust for Jersey a few years ago has really paid off.

The Plémont chick is a fast learner. It even picked up some cave art skills! Photo by Liz Corry.

It has been quite challenging to keep up with the youngster. When first bouldering outside of the nest it would hide behind rocks when mum and dad were off finding food. We didn’t manage to get any clear photos of it at this age. 

Born into the wind, the chick was quick to develop its flying skills. None of this hanging around the quarry clinging to the safety of girders and stairways.

There have been a few sightings of the family at Plémont. We probably won’t be able to give the chick an identity (leg rings, DNA sexing) until they start returning to the Sorel feeds. If they return!

The ones that got away

We returned to the quarry on 4th June to ring chicks too young to ring when we visited last month. The first nest belonged to Red and Dingle using a box in the asphalt plant. You may remember they had two young chicks. Now there were three!

Licensed ringer Dave Buxton discovered three chicks in the nest- box. Photo by Liz Corry.

The newcomer was 23 grams lighter than it’s siblings. Having hatched last, it had time to catch up. On 25th June the quarry reported all three chicks had fledged with parents attentive as ever.

Staff soon began to realise one of the chicks was in trouble. Whilst two had positioned themselves on the purlins of the building, the third was out and exposed to the risk of mechanical harm. Staff left doors to the building open hoping the parents would encourage the chick back to safety. Apparently the parents were shouting at it quite a lot; one assumes that is what they were trying to do!

Onsite CCTV allowed staff to keep watch on the chick; it appeared to be doing ok. After two days it wasn’t moving – at all. Sadly it had died. A post-mortem revealed a healed fracture in one wing. An underlying reason for its restricted movements around the asphalt plant? The interesting find was that this wasn’t the ‘runt’, but one of the older, larger chicks.

Choughs are full of surprises. When we went to ring Kevin and Wally’s brood on the 4th we found they had lost a chick pre-fledge. Disheartening as it was they had made up for it in size. They were huge! We remembered tiny, half-naked things. These were fully-feathered beasts. I’m pretty sure there is no literature on choughs feeding protein shakes to their chicks. We certainly didn’t find a nutribullet secreted in the building framework. Whatever they’ve been fed, the chicks survived and by the end of the month they were frequenting the Sorel aviary.

One of Kevin and Wally’s chicks having leg rings fitted. Photo by Liz Corry.

Other fledging news

We are pretty certain that all the chicks have now fledged. Unless any undetected nests along the north coast wish to make a claim – please do so now.

Proud to say we have new choughs flying around Jersey’s north coast from six different families. Somewhat disheartening to know there were broods or individuals that didn’t make it. From what we have seen it is simply a result of life in the wild.

One reason for loss is inter-specific competition within the quarry. I had a joyous moment mid-June watching Green and Black’s recently fledged trio being fed on the east side – where we used to supplemental feed released choughs.

Imagine my surprise as watching through the scope I saw a herring gull appear from nowhere and pin down a chick by the throat. Lots of shouting and wing slapping ensued.

Surprise attack by gulls on the recently fledged chough family. Photo by Liz Corry.

A pair of herring gulls pin down one of the chough chicks by the throat. Photo by Liz Corry.

 

A second gull joined in as did all the choughs in the quarry at the time. The chick managed to escape although I imagine it sustained injuries. Since that day we have only seen the parents with one chick.

The gull’s actions were not fully unjustified. They had a chick about two metres away from where the chough family had been hanging out. They were just doing their job of being good parents. With more choughs and increasing numbers of gull nests we are likely to see more of this behaviour.

Taken several days after the attack, this cute ball of fluff explains what the fight was about. Photo by Liz Corry.

An interesting anecdote from this event was how the other choughs reacted. They didn’t physically attack the gulls (a couple tried) it was more of an audible attack. Once the fighting stopped and one gull returned to their nest, the choughs stayed with the chough family almost like a standoff.

When it looked like matters had calmed down the choughs began breaking away going about their business. One pair returned to their nest in the lower quarry. Choughs truly are a social species.

Zoo chicks

Thankfully choughs raised in the zoo do not need concern themselves with gulls, peregrines, or dangerous rock-crushing machinery. Just their dad!

Tristan remained separated from Penny and the two chicks throughout June. The chicks look really well and have now fledged. We will look at moving Tristan back soon along with Gianna for the summer. 

Dobrodošli v Sloveniji ⁄ Welcome to Slovenia

I was invited to talk at Monticola’s annual meeting held, this year, in the Julian Alps, Slovenia from 11th to 16th June. Monticola is an association of amateur and professional ornithologists specialising in alpine species.

The Julian Alps in Slovenia were once home to red-billed choughs. Photo by Liz Corry.

This year’s focus was to discuss the feasibility of reintroducing red-billed choughs to Slovenia. Red-billed choughs disappeared mid-twentieth century from Slovenia (yellow-billed choughs are still numerous). Hunting is attributed to much of the loss. Change in land use and effects of pesticides and/or cattle worming are likely to be the other major players. A large proportion of alpine pastures in the Julian Alps have been lost to the encroaching commercial forest.

Caûvette the chough surveying the habitat. Photo by Liz Corry.

Various day time excursions were planned along with evening talks. Members of BirdLife Slovenia (DOPPS) talked about their work and joined me for a scary panel discussion on reintroducing the chough. I say scary, not because of the stature or responsibility being on this panel. Rather because it was in German…and Slovenian!

Tomaz Mihelic, BirdLife Slovenia, gave talks about monitoring and conservation of various Slovenian species. Photo by Liz Corry.

 

BirdLife Slovenia don’t just work with birds. Photo by Liz Corry.

Monticola members are mainly German or Swiss-German. To add to the fun, the German for red-billed chough is Alpenkräuhe which is not the same as the Alpine chough known in English as yellow-billed choughs.

Promo material handed out to Monticola members. Photo by Liz Corry.

Thankfully I had the lovely Johannes and Arnette Denkinger who took me under their wing. Johannes had invited me to speak after reading about Birds On The Edge. It has been his passion for many years to see the return of the red-billed choughs to the eastern Alps.

Birdlife Slovenia did not appear to be against the idea, but raised the realistic challenge of limited resources and existing government priorities. Using evidence from Jersey, and Durrell’s ethos, we all agreed there was scope to create a similar project to Birds On The Edge in Slovenia whereby the focus is restoring alpine pastures. Support is already there within the German zoo community where a captive-breeding programme has been initiated. Tiergarten Nuernburg are leading the work and have invested in habitat feasibility studies.

At the end of the day this needs the people of Slovenia to be behind it. A challenge Johannes is prepared to take on!

Caûvette the chough taking a break at Lake Bohinji. Photo by Liz Corry.

Insurance Corporation Conservation Awards 2019

Congratulations to Birds On The Edge partner the National Trust for Jersey who were awarded runner’s up prize for their conservation meadow at The Elms. The winners were SCOOP The Sustainable Cooperative for their soon to launch ‘Re-Wild my Plate’ initiative.

Glyn Young presenting Kaspar Wimberley of SCOOP with first prize at this years Insurance Corporation Conservation Awards.

Glyn Young was one of the judges and presented the awards at a ceremony held at the Pomme D’or Hotel. I gave a short presentation explaining how we spent last year’s award money supporting the chough project. We must state for the record there was no vote rigging!