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.

 

 

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