As the year drew to a close and daylight hours dwindled to their annual low, the choughs spent more and more time at Sorel close to their roost sites.
Chough movements in December
There was one intriguing public report at the start of December suggesting a new roost site. Farm workers at West Point Farm, St Ouen, had been seeing a pair of choughs in their barns around 7am each morning. At that time of year sunrise occurs around 7.40am. Was the pair roosting in the barns or being ‘the early bird that catches the worm’ and leaving Sorel before everyone else to find food out west?
Choughs leaving the feed site at Sorel. Photo by Liz Corry.
The day of the report, and each day since, there have been 35 choughs at Sorel for the feed. The sun sets not long after with a dozen or so choughs staying at the aviary and the rest heading east, presumably to the quarry.
Taking in the last rays of a December day. Photo by Liz Corry.
Another reason to stay close to Sorel is the supplemetal feed. Now that winter has set in the availability of wild food is low and the need for calories high. December has not been particularly cold – in fact there have been a few balmy days where shorts were an option (for keeper not bird).
An unusually warm day in December enjoyed by the choughs. Photo by Liz Corry.
However, our tiny island has taken a constant battering over the past weeks with gale force winds of 40 to 60 mph. It is bad enough walking or driving in it. Imagine being a 300g bird trying to fly or trying to stay grounded whilst searching for food in the soil.
24 hours later! (note the choughs on the roof) Photo by Liz Corry.
Apart from a demand for more food the choughs have on the whole faired ok so far with the bad weather. They are making the most of the sheep being confined to the aviary field. It is tupping season with one lucky ram confined to two fields with a flock of ewes. Lots of dung with maybe the odd tasty insect morsel inside.
One lucky ram confined to the aviary field at Sorel for tupping season. Photo by Liz Corry.
The choughs have been foraging in amongst the sheep confined to the field adjacent to the aviary. Photo by Liz Corry.
Syngamus strikes again
There have been two cases of syngamus infection this month. Luckily I was able to trap the birds, Lee and Duke, within a couple of days of symptoms showing. They evaded capture on the first day of trying, partly due to the hatches not budging when released (if anyone can come up with a better release hatch design I will pay you! albeit in chocolate coins). The second day their hunger in the increasingly cold wet weather spurred on their motivation for staying inside the aviary and the hatches closed. Much to the relief of the vet on call over Christmas as it was the 23rd December.
Never easy trying to trap choughs who refuse to go inside. Photo by Liz Corry.
Whilst Lee had been our major cause for concern due to gaping and repeated sneezing, it was Duke who sounded the most congested once we had him in the hand. He also had a lot of mucus around his nares which we rarely see.
Duke presented with mucus coming from his nares as a result of infection. Photo by Liz Corry.
Once they had received their wormer injection they were released and left to feed on the pellet and insects at the aviary. Remarkably there have been no observations of sneezing since that day. However, do bear in mind the gales/fog/heavy rain/sleet (often in the same day) have meant that there is little incentive to hang around at Sorel observing birds.
We have tried. Body weights have been obtained for several of the birds. Not consistently to show any trends, but enough to know the choughs getting on the scales are not underweight. These of course will be the more confident individuals and/or ones that have low parasite loads. We have a new type of scale that the birds will use. A lot cheaper than the flat Kern scales (£20 versus £150).
Prototype weighing station using digital kitchen scales. Photo by Liz Corry.
They are not intended as outdoor scales so I have had a few attempts at weather-proofing. The current one needs improving as the birds are unsure. Once they have approved the design plans we can make several weighing stations to place around the aviary ensuring we cater to all of the choughs.
Towards the end of November keepers at the zoo started to notice Gianna our foster mum having issues. She was crash landing when flying. Gianna is tame and she lets keepers get extremely close. She lets me open her bill to check for infections or blockages if needed. It was easy to see that the source of Gianna’s mobility problems was her eyes.
Gianna’s left eye was starting to show signs of cataract. Furthermore, there was no reaction in her right eye. She was taken to the Vet Department for further examination. Photos were sent to a UK specialist who confirmed she had cataracts in both eyes.
Jess Maxwell with Head Vet Andrew Routh examining Gianna’s eyes. Photo by Bea Detnon.
Since the initial assessment there has been a noticably downturn in her ability to move around. Understandably as her vision deteriorates her confidence in everyday things like hopping from rock to rock has decreased. She has been moved to an off-show aviary close to the Vet Department so she can receive the best attention from keepers.
Cataract forming in Gianna’s left eye at the start of December. Photo by Liz Corry.
The cataract in Gianna’s left eye by the end of December. Photo by Bea Detnon.
Despite everyone’s love for Gianna we have to accept that her future is murky. There is the option of an operation to remove the cataracts. As you can imagine this is very specialised, expensive, and relies on the individual being strong enough to undergo the operation. For those of you interested in avian ophthalmology click here. If the operation option is not feasible her quality of life will then need to be carefully considered.
From all of us at chough HQ we hope you enjoyed your Christmas holidays and wish you all the best for 2018. Thank you for your continued support.
Choughs took flight this month to explore the west coast of Jersey. Photo by Trevor Biddle.
By Liz Corry
Having spent most of November on holiday or in bed overdosing on Lemsip, I thought I would get away with not having to write anything this month. However, as is now tradition, it is times like these when the choughs start hitting the headlines. So, thanks entirely to public sightings, I have the following news to share.
New sightings for November
There have been a couple of positive sightings of choughs at Petit Port and Corbiere once again. We never know every individual involved, but we do get at least one or two positive sightings of choughs in the area each year around this time and this year we have had some positive identification like Roy Filleul’s photo of PP003 at Corbiere and Mary with friend in the NT Field, St Ouen’s Bay.
Staff at Simon Sand & Gravel Ltd had a surprise sighting of two choughs flying around their buildings on 3rd November. They managed to film it and post on their Facebook site, see below. Since then we have been receiving reports of choughs making the most of St Ouen’s Bay. It tends to be 2 to 3 birds at a time, no large groups, and they are seen in the same places (although there could be observer bias in that).
We had a report of a chough drinking from the water’s edge at the St Ouen’s Pond Scrape (in front of the Eddie Buxton hide) which is personally very exciting as I’ve only ever seen them drink from the aviary water tray and the sheep bowsers.
Kempt Tower and Les Mielles nature reserve are becoming popular with at least three of the choughs. Thanks to Trevor Biddle’s photo of them down at the Scrape (south of St Ouen’s Pond) we know the identities of the three explorers; Pyrrho and wild-hatched siblings known to us as PP004 and PP005. Rather interestingly these three have been a trio since the start of this year and observed carrying nesting material towards the quarry back in spring.
Three sub-adult choughs spotted by a member of the public near the Scrape, St Ouen’s Bay. Photo by Trevor Biddle.
It is likely that people are seeing the same three in the area, but without leg ring information this cannot be confirmed. Understandably that information is hard to obtain, it is amazing just to get photos. All this knowledge feeds back into their long-term management plan so if you do spot choughs out and about in Jersey please do send in your report to firstname.lastname@example.org or call 01534860059 and leave the details.
Two choughs in the NT Field, St Ouen’s Bay. 5-11-2017. Photo by Glyn Young
Chough numbers in Jersey dealt another blow
One chough who will not be venturing further afield anymore is Egg. We had a rather sad report from Ronez Quarry of a dead chough found behind the door inside one of their buildings. On collection of the body the leg rings told us the bird was a captive-raised female known as Egg. What we did not know was the cause of death since the body looked to be in good condition and time of death fairly recent. She was taken to the Zoo’s veterinary team for post-mortem analysis.
X-rays ruled out any kind of trauma. She was underweight, but there was no evidence that she starved to death. Syngamus was present, but at a very low encounter rate. Internal investigation showed problems in her lungs and presence of acanthocephalans, a type of parasitic worm also known as thorny-headed worm. Once again we cannot say for sure that these factors caused the death, but certainly played a part in her demise. We are waiting on histology results for further information.
Captive-reared chough, Egg, collecting nesting material at Sorel back in April. Photo by Liz Corry.
This brings the chough population down to 35 individuals; 12 males, 23 females. It also means we have lost a potential breeding female. Egg was partnered with Dusty and for a second year in a row had made a nest although nothing came of it. We will now need to keep watch on Dusty. Will he form a new pairing in time for the next breeding season only a couple of months away? Will Chickay finally get her chance after spending two loyal years following him? More importantly was Egg‘s cause of death a one-off or is something sinister afoot?
Julian Hume and Lindsey Hubbard visited the aviary on 13th November. Julian, better known for his work with extinct bird species was excited to watch such an exuberant, and very much living, species!
Extension request for release aviary
The release aviary at Sorel was originally granted a five-year lease of life under States of Jersey planning regulations. As this comes to an end this month we have submitted a request to extend permission a further five years.
We still have a a group of choughs using the aviary as a roost site (not to mention kestrels and barn owls). There is still a need to recapture birds for veterinary treatment as demonstrated in last month’s report. The aviary facilitates this need.
In the long term we are also looking at introducing new blood lines into the population which would require soft-release of captive reared individuals. We still aim to remove the aviary at some point in the future, but for now there is still a clear need for the structure.
More information and opportunity for public comment can be found on the States website by clicking here.
The required planning notification went up at the aviary on 9th November and has, thanks to high winds, been replaced four times!
A few of the Jersey choughs signalling dinner time. Photo by Liz Corry.
By Liz Corry
As October drew to a close it was achingly apparent that the chough flock was down from 38 to 36 individuals. The two wild-hatched females who went missing in September had still not made an appearance, forcing us to reluctantly record them as missing presumed dead.
This is the first time we have lost wild-hatched birds post-fledging period. One can’t help feel a sense of responsibility. These individuals were known to have a nematode infection, but attempts to medicate them had failed before they went missing. All we can do now is monitor the remaining choughs to ensure the same fate doesn’t befall them.
So we did, and guess what…two of the adults started sneezing. Egg and Helier began with the ‘I’m not sneezing, just clearing my nostrils’ subtle sneeze. After a few days Egg stopped whereas Helier continued and progressively worsened.
After a few failed catch ups due to jammed hatches, intelligent corvids, and of all things Portuguese forest fires (see ‘Sepia skies’ below) Helier was finally locked in the aviary allowing her to be treated by the vet team. She was released back into the wild straight after her worming injection and appears to be much improved.
Nematodes are part of the natural ecosystem. Choughs feeding in the wild will be exposed to them and have to tolerate or succumb. This year is turning out to be the worst since the project began in terms of number of infected birds and fatalities warranting further investigation.
Having worked at Sorel for several years now you would have thought that everything that could go wrong in a catch up had done or at least been theorised and accounted for. Hinges sticking on trap doors, birds not showing up or not hungry enough to want to go inside, mountain bikers zooming past scaring the flock into the air, etcetera. Not once had we thought to account for Caribbean hurricanes and Portuguese forest fires!
On the morning of the first planned attempt to catch up Helier the skies in Jersey, and parts of the UK, were looking very ominous. Walking around Sorel it felt like someone had put a sepia filter on the world. Frustratingly my camera phone kept adding its own filter so the photos below don’t fully set the scene.
On 16th October 2017 the skies above Jersey turned a sepia colour. Photo by Liz Corry.
Low cloud filled the skies throughout the morning. Around lunchtime the sun made an appearance, but looked more like Mars than our beloved sun. There were no horsemen on the horizon so instead of embracing impending doom I turned to the Gods of Google.
A red sun breaking out from the cloud of dust and ash in the atmosphere. Photo by Liz Corry.
An explanation for the near apocalyptic conditions was provided by the BBC. Remnants of Hurricane Ophelia passing over the south of England and Channel Islands were dragging dust from the Sahara and smoke from the devastating forest fires in Portugal and Spain across our skies.
I tried explaining this to a very confused flock of choughs who were clearly conflicted about what time they should go to roost. One might think this would be advantageous to someone trying to lock birds in an aviary. Nope. Instead it meant they just sat and stared at me in their perplexed state. A twenty-minute stand-off resulted in a dejected keeper walking away left to come up with a Plan B.
Plan B failed. In fact it wasn’t until Plan E was executed that we were able to lock the sick chough in the aviary. The new plan arose from the need to know who was roosting in the aviary in case we had to lock in the sick bird for longer than a day. There was a small chance she roosted in the aviary already rather than the quarry. If so, all we had to do was wait until the birds had gone to roost and quietly shut the external hatches.
Cut to the scene of a person in dark clothes vaulting a field gate at night only lit by the stars and the dim headlights from a teenager’s car (one assumes from the discarded firework packaging and soda cans found the next morning) idling at Sorel Point.
The operation provided extra information other than Helier’s roosting site. A total of twelve choughs were roosting inside the aviary including Dusty the very first wild-hatched chough and the two females who follow him.
Kevin and Bean were hanging around outside the aviary. They could have used one of the external roost spaces at the aviary or simply flown over from the quarry at first light to forage nearby. The other interesting find was the kestrel who shot out of the external roost box when I arrived in the morning to check on the choughs.
There are no photos from Operation If this doesn’t work we’re screwed. So instead here are a couple taken at Les Landes when checking for signs of choughs at sunset.
A view of the Pinacle at sunset. Photo by Liz Corry
Sunset at Les Landes. Photo by Liz Corry.
The Women’s Institute expedition to the north coast
Earlier in the year the ladies of La Moye WI had invited me to give a talk about the choughs. Several of their members were already aware of the project, but had not realised that the historic breeding sites for Jersey choughs were in fact along the coastline at La Moye.
Enthusiasm for the project continued to grow as the evening went on, fuelled by the obligatory tea and cake, and by the end of the night a trip to Sorel was penned in the diary.
After a few clashes in the calendar a small group from La Moye finally made it up to the north coast this month. Glyn walked them around the conservation fields and release site. Not all of the choughs were present, but certainly enough to make an impact and demonstrate their amazing flying skills. I sadly missed out as I was in England, but from the looks on their faces I think they enjoyed it.
July 2016 saw the official opening of Plémont Headland and for the first time in over 140 years (before the original “Plémont Hotel” was built in 1874) the public have been free to enjoy this special place.
Creating and protecting “green space” for people has been at the heart of the Plémont debate and acquisition and indeed forms a very important part of the National Trust for Jersey’s ethos. But ensuring that nature has a home is also a vital component of what we do and there has never been a time when action has been so desperately needed.
In 2015 The States Department of the Environment published the results of the Jersey Butterfly Monitoring Scheme after 10 years of collecting data across 38 sites by a team of dedicated volunteers. The results suggest that whilst Jersey’s butterflies might be faring slightly better to those in the UK, the surveyed population has still decreased by 14%, (compared to 29% in the UK). Interestingly Jersey’s butterfly population is doing best in semi-natural sites as opposed to those in agricultural or urban habitats where they are declining. In fact the green hairstreak is one species that is doing particularly well and has been recorded as increasing by 458% in the last 10 years as opposed to suffering a 40% decrease in the UK. This could be seen as a strong indication of the importance of managed semi-natural sites such as Plémont.
The creation of two ponds at Plémont was eagerly anticipated by the local toad and palmate newt population, who were literally queuing up to jump in upon their completion. For two consecutive years the Eastern Pond has been used by both species to breed. This year, the larger Western Pond has seen a whole new generation of toadlets emerge after metamorphosing from their tadpole stage.
Despite the amphibian successes, both ponds have experienced teething problems and most noticeably the appearance of the lime-green algal blooms. Spirogyra is a family of around 400 species of filamentous algae that is commonly found in freshwater and is indicative of clean water that has high concentrations of phosphates and nitrates. It can be easily removed but doing so would jeopardise any invertebrate life or tadpoles that would become encapsulated amongst the tiny strands of algae.
Another issue the ponds face is loss of water through evaporation, due to their exposed position to the sun, wind and transpiration – the evaporation of water from plant leaves. Whilst there is means to top up the water levels from a well, this would mean the introduction of more nutrients which would cause more algae. The proposed solution is to encourage more oxygenating plants and remove the algae once the toads have emerged from the water, decreasing the level of nutrients over time. Equilibrium will be reached, the water quality will improve and we will have to accept that the water levels will drop in the summer months. As long as there is water during the amphibians’ breeding period (February-June) the pond is serving its purpose and will act much like many natural ponds without constant water inflow.
Back in the spring of 2015 you may remember the huge mounds of sandy soil which were spread over the footprint of the demolished buildings. Over 7,000 tonnes of sandy soil, sourced from Les Quennevais and recycled soil from La Collette formed the base of what we now refer to as the restoration area. To create a heathland such as Les Landes we would need a free draining sandy soil with a low pH (pH 5-6 ideally) and low nutrient levels. It is easier to maintain a species-rich wild flower habitat when there are fewer nutrients in the soil. If you add fertiliser (or compost or a lot of manure) to the soil, a small number of competitive plants are able to rapidly exploit these extra nutrients. These species then tend to become dominant and other plants are less able to compete for space. Most plants rely on a relationship with fungi and soil micro-organisms in order to grow. Fertilisers have a negative impact on these organisms making it more difficult for the flowers to grow. With very little choice available, in the quantities we would need, a mixture of sandy soil, sourced from Les Quennevais and recycled sand from La Collette was chosen. Although the average pH was around 8.5, the particularly low nutrient status would mean far less of a burden when it would come to managing the developing vegetation.
This June our Conservation Officer, Jon Rault, assisted by the very knowledgeable local botanist Anne Haden, undertook a vegetation survey to assess how things have developed and have some interesting results. Around 50 plant species have so far been recorded including: wild carrot, toad rush, birds-foot-trefoil and small-flowered catchfly. Maritime Duneland plants such as fragrant evening-primrose, sea beet and sea radish have appeared, but this isn’t so surprising considering the origins of the soil, Les Quennevais of course being built on Dunes. Some more invasive plants such as the non-native cape cudweed and spotted medick which may need some management have become quite well established and some more exotic species including echium and Californian poppy have appeared as likely remnants of the holiday camp era.
Resent soil tests have confirmed that pH levels are still rather alkaline at between pH 8.5 and 8.9 and this is unlikely to change without any intervention due to the amount of concrete based material that must be underneath the layer of imported calcareous sand. Perhaps more encouraging is the nutrient status results from the same soil samples. For example, the amount of available phosphorus is currently between 8.8 and 25.8 mg/l with a “P index” of 0-3, compared to a recently tested former agricultural field which showed levels of available phosphorus at between 66.2 and 153.4mg/l giving a “P index” of between 4 and 7.
Our current situation, with the encouraging results of vegetation surveys, indicates that the soil choice was a good one. Whilst our soil pH is much higher than we would have ideally liked, this is something that can be changed by adding sulphur, an expensive but affective way of raising acidity. As the results from the former agricultural field’s shows, high soil fertility is much more of a problem with no “magic cure”.
The decision on whether to try to acidify our soil in the effort to meet our original vision of creating a heathland is not one that needs to be made straight away and whilst wildlife and people are clearly making good use of the site, we have already achieved much of what we wanted to do.
For the meanwhile, the addition of calcareous grassland to our north coast may be something of an oddity but this may also be its strength and reason to remain as such. A new and interesting patch adding heterogeneity to the landscape is something that’s often lacking.
Further decisions will be required but there will be a need to balance and create opportunities for nature as well as public access and enjoyment.
This piece was originally published in the National Trust for Jersey magazine Discover and is reprinted here with kind permission
“Delicious autumn! My very soul is wedded to it, and if I were a bird I would fly about the earth seeking the successive autumns.” – George Eliot
If that bird happens to be a Jersey chough, substitute “earth” for Les Landes and “successive autumns” for lots and lots of insects. For the first time since the choughs have been living at liberty, the entire flock have snubbed their morning supplemental feed in favour of wild pickings out at Les Landes.
Chough spotting in the middle of Les Landes Racecourse (the red circles indicate choughs, not cowpats). Photo by Liz Corry.
Choughs taking flight at Les Landes Racecourse. Photo by Liz Corry.
They have been flipping over and picking apart cow pats, probing the grass on the spectators’ stand at the Racecourse for cranefly larvae, and scouring the cliff face for anything else they can prise out of the ground.
A group of choughs (under the arrow) and starlings foraging in the spectators’ area of the Racecourse. Photo by Liz Corry.
This is obviously encouraging news for the project. The choughs are clearly content and they are gaining popularity with the public, both locals and tourists who delight in watching their antics. Especially the flying displays.
For the lone observer tasked with keeping track of all 38 choughs it is a roller coaster of emotions; pride, joy, irritation, despair etc. The blessed things don’t stay still nor in one group and it is near impossible to read leg rings. Add to that the inevitable sod’s law factor and you get events such as (1) Racecourse tractor mowing back and forth along your observation site (2) friendly kestrel spotting lunch slap bang in the middle of the foraging chough flock sending them scattering just as you are half way through counting said flock and (3) random 10 minute hail storm!
La Nethe Falaise is a favourite spot for the choughs to hang out when they are up at Grosnez. Photo by Liz Corry.
There is, however, one trick of the trade that can be deployed and moments of need. It should only be practised by a trained professional. It can only be practised by a trained professional since without the recognition from the foster-reared and hand-reared choughs it probably wouldn’t work and you would be left looking like a right Parus major (one for the bird geeks).
Like any species, the offer of free food is too tempting and providing I can get close enough in an area where the birds do not feel threatened I can get the choughs to gather together in one place. Note in the video and photos the choughs closest to me are Ubè and Vicq, both foster-reared, and a couple of the older adults who have known me for four years.
Thirty of the choughs getting a sneaky supplemental feed at Les Landes Racecourse. Photo by Liz Corry.
It is possible to identify most of the leg rings when the choughs are this close. Right up until the point when sod’s law example number 2 comes into play. After that, only the clingy types stay behind begging for more free food.
For the past few weeks the maximum number of choughs at any one time has been thirty-four. There should be thirty-eight. The individuals who appear to be absent most often are Lee and Caûvette, their chick Pink, and Carmine another wild chick hatched this year.
Carmine, a wild chick from this year, was last seen at the aviary on September 2nd. Photo by Liz Corry.
Whilst it would be nice to assume Pink is with her parents, both chicks are of an age now not to be dependent on their parents. Furthermore they were both showing signs of having nematodes back in August. Failed attempts to catch them up in the aviary meant that they were never treated before they were last seen at Sorel at the start of September.
It is quite possible that Carmine and Pink have sadly perished. Ever optimistic we will continue monitoring the population and ask the public to keep their eyes (and ears) open.
As a footnote, apologies for the media quality this month. The trusty camera has packed up and I am relying on my camera phone!
This month has flown by. So have the choughs. Awful opening line, but accurate. Now that the breeding season is over the choughs are spending more time away from Sorel and it is quite rare to see all 38 choughs at the supplemental feeds.
West is best?
Lee and Caûvette are back at Les Landes and Grosnez. This time with their chick in tow. We were treated to several sightings of the family whilst we carried out rat monitoring fieldwork at Plémont. The most memorable sighting was that of all three flying through the early morning fog towards Grosnez. These days they spend the whole day out west, returning to Sorel an hour or so before roosting time.
Lee photographed by a member of the public at Grosnez castle. Photo by Mike Nuttall.
They are not the only ones on the move. A sighting from an ex-Durrell colleague of seven choughs flying over Hamptonne Country Life Museum added to the tally of sightings in St Lawrence parish.
All of the reports from St Lawrence are of birds flying over. Are the choughs just passing through or checking out the parish for suitable feeding site?
Their daily activities are making it a little harder for the team to monitor every chough as closely as we have in the past. Although we have still kept on top of monitoring their health and welfare. It is hard not to when you can get this close…
Syngamus infections in the wild chicks
Last month we reported that the wild chicks were sneezing and sounding congested. We managed to obtain individual faecal samples for three of the four chicks after patiently waiting at each feed. All three tested positive for syngamus nematodes. The fourth bird is proving harder to sample as it disappears out west with it’s parents each morning.
We have so far managed to trap and treat two of the chicks. We are still trying with the third. The chick we treated in July has shown a great deal of improvement which is encouraging.
Durrell vet nurse, Teresea Bell, examining one of this year’s wild chicks. Photo by Liz Corry.
Perils of living in the wild
One of the wild chicks had to be caught up for a second time this month. Beanie baby had plastic thread entangled around her foot. It was quite a mess and needed cutting. Luckily there was no damage and she was free to rejoin her parents. The other good news is that she had put on weight since the last catch-up to treat her for syngamus. We can’t hear her wheezing or sneezing anymore suggesting that the treatment has worked.
Plastic sack thread entangled around the foot of one of the wild chicks. Cut loose prior to photo being taken by Liz Corry.
We received report this month from a family who live close to the release site. They were pleased to see three choughs chilling out on their roof taking in the local scenery. We see a similar sight at Crabbé on the granite farmhouse and in Mourier Valley.
What is particular nice about this photo is the choughs sat on the witches’ step, or pièrres dé chorchièrs in Jèrriais. These are flat stones jutting from chimneys of granite houses in Jersey. According to Channel Island folklore, these small ledges were used by witches to rest on as they fly to their sabbats, i.e. meetings. In doing so the homeowner would be looked on favourably by the witch. One witch, Marie Pipet, from Guernsey was said to possess the power to turn herself into a chough!
Enrichment ideas for the captive choughs
Project student John Harding was set the task of designing enrichment feeders for the choughs in the zoo. Gianna, the tame chough, took up the role of R&D assistant and put them to test. She probably did more eating than assisting, but it still helped John find a winning design.
He also learnt a great deal as he discovered that ‘product placement’ is just as important as design. There are certain areas within the aviary, mainly on the ground, that Gianna does not like going to. In some cases it was a matter of gaining her confidence. In others she just outright refused to go and therefore a waste of time putting enrichment there.
One of this year’s wild-hatched chicks arriving at the aviary. Photo by Liz Corry.
By Liz Corry
Previously on Choughs…cue theme music…On 27th June Beanie baby was the first of four wild chicks to appear at the aviary with parents, Kevin and Bean, by its side.
Six days later another chick arrived. Unringed, but accompanied by Green and Black, and sneezing and wheezing, so it wasn’t hard to determine which nest it came from. It wasn’t hard to find a name for the new chick either. Lil’ Wheezy, who clearly wasn’t well, but it had made it to the aviary, so it’s odds were looking up.
A wild-hatched chick arrives for the first time at the aviary with parents begging for food. Photo by Tanith Hackney-Huck.
The third chick made an appearance on 5th July. We knew which nest it came from because of we could see pink and black leg rings. We didn’t know who it’s parents were. Well, not until it started guzzling food down its throat provided by Lee and Caûvette. This meant that our Les Landes pair had been travelling 9km away from their nest and the group finding food for their chick.
The news of this chick also means that another of our four hand-reared choughs has successfully bred in the wild; Dingle (fathered two in 2016), Caûvette and Bean. Poor Chick-Ay has yet to find a dedicated partner.
The fourth and final chick was spotted flying around the quarry on 6th July. Again, we knew which nest it was from, but did not know the parents. Two days later we were in for a pleasant surprise. Q and Flieur, a new pairing, led their chick over Sorel Point to join the flock feeding at the aviary.
This now brings the total number of free-flying choughs in Jersey to 38. Almost a quarter of which were wild born in Jersey. There is a video of the group in flight on Jersey Zoo’s Instagram page or just click here if you don’t have an account.
Lil’ Wheezy gets wormed
We needed to worm the sick chick that was now visiting the aviary twice a day. It couldn’t be done straight away. We needed the chick to become accustomed to flying in and out of the aviary in order to trap it inside. It took a good week for Lil’ Wheezy to grow in confidence and fly all the way in at each feed.
A wild fledgling caught up under licence to treat for nematodes. Note the bill colouration due to its young age. Photo by John Harding.
Patience paid off on the 19th when the team were able to trap it inside and catch under licence. Dave Buxton fitted leg rings and the Vet gave it a wormer before being released back to it’s parents and the rest of the flock.
Classic reaction to a vet holding a needle. Photo by John Harding.
MSc project wraps up
Guille finished collecting data for his research at the end of this month. He now has the delight of returning to Nottingham Trent University to make sense of it all. I will let Guille explain in his own words…
“Birds, and other animals have personalities. Consistent behaviours that are different between individuals, maintained through time and favouring -or not!- the survival of the individuals and their successful breeding.
Studying the boldness-shyness continuum in choughs. Photo by Liz Corry.
With the choughs I am looking at a classical behavioural trait: the boldness-shyness continuum and how it might affect survival.
Basically, if you are a bold bird you may be good at defending your food patch from others, get stronger and healthier and be able to feed your nestlings properly. However, if you are a very bold bird that would not leave the food patch even when there is a falcon approaching, you are in serious trouble.
I want to see if we can predict how far the released choughs will go to find food everyday just by looking at their personalities. Some studies have already shown that boldness has an effect on habitat use and distance travelled, which may be useful in a project like this one, where every bird is highly valuable and the distance they will travel will increase the chances of finding more food, or getting lost! If a correlation is found, it would help the project team to select which birds should be released depending on what behaviour is best to assure survival in the area.
Does Lee’s personality type predispose him to travel several kilometres away from the release site to feed? Photo by Mick Dryden.
For assessing their boldness, I presented them a squirrel-proof bird feeder that they had not seen before, as they have their daily supplementary feeding in open trays. I recorded the latency of each bird to pick food from it for the first time, during 15 minutes. After that, they were given their daily meal and I would not repeat the test until approximately ten days later, so they would not get used to it. Finally I gave every bird an average boldness score based on how long they took to pick food for the first time.
This year’s wild chicks were clearly not shying away from the feeder. Photo Guillermo Mayor.
Assessing the distance travelled was the fun part, as they had lost their radio tags. I had to become another chough and follow the group during their morning stroll. They leave the roost by 5am, returning for the 11am feed. I learnt lots about chough behaviour in the field. I saw their games, love arguments, gang fights, first trips of their chicks, but still they are very complicated birds.
By the end of July, after having cycled every single track of the north coast, I had a bunch of observations, from which I would pick the furthest point from the roost I saw each bird. Some of them were a bit surprising, such as Trevor and Noirmont. I found them perching on a German WW2 cannon, south of Les Landes. They looked like nobody could mess with them. I would definitely keep an eye on those two.
The two and a half months passed too quickly and I wish I could have stayed longer. The support I received from the project staff was amazing, and I would definitely recommend anyone that has cool ideas that would help the project and the broad bird recovery knowledge to think about doing some research here.
I am currently in front of the computer, missing the field and the choughs, and for now it seems that the boldness was consistent, which is good news! I really hope I can come back soon and see the noisy choughs again soaring over the windy cliffs, and all the lovely people who were like a family for a summer.”
Birds On The Edge wins a RHS award
Birds On The Edge received a Silver award in the conservation section of the annual ‘Parish in Bloom’ event, a hugely popular and well supported national floral competition held under the professional auspices of the Royal Horticultural Society.
Glyn Young met the judges and Mike Stentiford on Sunday 23rd July to show them around Sorel to see the grazing flock of sheep, conservation crop fields, and the choughs. Although only two choughs showed up!
Jersey’s free-living choughs have had another productive nesting season. There are seven pairs in the group and we discovered five nests. As reported last month, Dingle and Red’s clutch of four eggs failed to hatch.
That still left four active nests with chicks. The team was taken to the nest-sites on 9th July by Ronez operational assistant, Toby Cabaret. Dave Buxton, licensed ringer, joined the team in order to fit leg rings on the chicks.
We were initially greeted with bad news. We found two dead chicks on the floor under a nest, approximately two and three weeks old at time of death. Post mortem results were inconclusive due to decomposition of soft tissues. Fortunately there was still one chick alive in the nest.
Licenced bird ringer Dave Buxton with a chough chick. Photo by Liz Corry.
Fitting plastic leg rings and taking DNA samples for sexing. Photo by John Harding.
A second nest had also lost a chick leaving just one chick for the team to process.
The third nest was checked and also found to contain just one chick. In all of the above nests, the parentage was unknown; although we had our suspicions.
Each nest checked contained one chick. Photo by Liz Corry.
The fourth nest belonging to Green and Black was in one of the nest-boxes fitted this year. Despite the nest camera being blocked with wool and twigs we had strong suspicions there were chicks inside. Due to access issues it would be a case of waiting for fledglings to emerge to determine if this was the case.
On the 21st we received news from Toby that one of the ringed chicks had started to explore outside the nest. We estimated it would be a week before it made an appearance at Sorel.
Photo of the first chick out of the nest. Photo by Toby Cabaret.
We were right! On the 27th the dulcet tones of a begging chick could be heard over the cliff tops and upon its arrival at the aviary accompanied by its parents. Finally we knew who its parents were. Kevin and Bean were the only two choughs hurriedly feeding the chick. This was quite a moment for the team since young Bean is one of three hand-reared females at Sorel. There could only be one name for this chick; Beanie baby.
The first fledgling to arrive at the aviary begging for food from its parents. Photo by Tanith Hackney-Huck.
Our question over the fourth nest was answered two days before Beanie baby flew to Sorel. Paul Pestana’s voluntary observations paid off on the 25th when he spotted a commotion on the roof of one of the quarry buildings. Two chicks had jumped up through a hole in the roof and started begging frantically at Green and Black who had returned with food from Sorel. Within minutes of being fed they hopped back out of sight and the adults flew off to find more food.
This breeding season seems to be one of give and take. Therefore, our news of two unringed chicks was followed by news of a loss the next day. Concerned quarry staff phoned in the morning to report a chick on the ground in a building looking like it couldn’t fly. A somewhat common appearance in chough chicks that haven’t fully fledged. However, it soon became apparent it was more serious. Sadly the chick died before it reached the vets. A post-mortem showed a severe syngamus infection as likely cause. Black was showing symptoms of a syngamus infection. If she was ingesting infected insects it was highly likely she was also feeding them to the chicks. The survival of the second chick was now in doubt, but there was nothing we could do until it flew to Sorel.
Whilst staff have been busy observing nests, the choughs have been off gallivanting along the north coast. Nottingham Trent student Guille has been attempting to follow them as part of his MSc project. He wakes at dawn and tracks groups or individuals armed with a pair of binoculars and a trusted bicycle. He also put a plea out to the Jersey public via social media to report any sightings. They didn’t disappoint.
After an initial slow start, Guille has been able to observe choughs foraging at Crabbé, Plémont, Grosnez, and Les Landes. All places we knew they visited already, but thought they had ditched during the breeding season to stay close to nest sites. At least that is the impression you get when you go to the aviary to feed twice a day.
One warm day, a pleasing find was seeing a group of choughs bathing and drinking in the stream at Mourier Valley. Rather more interesting was the discovery of the breeding pairs travelling several kilometres away from their nest sites. White and Mauve with at least 16 others were photographed at Grève de Lecq at the start of the month. We had started to think this pair had failed to breed this year, so it wasn’t too surprising for them to be away from their nest site.
Choughs photographed at Greve de Lecq on June 12th by Nick de Carteret
We suspected the Les Landes pair, Lee and Caûvette, were responsible for one of the chicks in the quarry. Guille’s observations and public reports meant that the pair were spending considerable time and distance (~5km) away from their nest to forage. Grosnez, Plémont Headland, and Les Landes being their favourite spots. Kevin and Bean were also spending time away from their nest having been seen 2-3km away in the mornings and early afternoon.
Lee (on the left) and Caûvette photographed at Grosnez by Mick Dryden.
Catch up with Caûvette
We trapped Caûvette in the aviary at Sorel and caught her up to remove her back digit from her plastic leg ring. Unlike Bean she had not managed to free it unaided. There appeared to be no damage. The only thing was that claw had become overgrown and needed a trim. Once weighed she was released from the aviary to join the others. In the process of catching her up we also caught up Green and Q much to their displeasure. Not one to waste an opportunity we recorded body weights for those two prior to releasing. The two males and Caûvette were all good weights suggesting that they must be finding enough food whether wild or at the aviary.
An unappreciative Cauvette before her toe was removed from the plastic leg ring. Photo by Liz Corry.
Han Solo takes flight
Zoo chough chick Han Solo in the nest box…one imagines anyway.
Our zoo chick, Han Solo, took his first flight out of the nest box on 15th June and there wasn’t a Millennium Falcon in sight! Well maybe a kestrel hovering over the valley.*
He had been teetering at the edge for several days beforehand. Once out it took him a little while to get used to his new-found flying skills, preferring to hang out in one of two places. He doesn’t seem too perturbed by the public. We assume mum and dad have explained the situation to him.
Recently fledged chough chick and parents at Jersey Zoo. Photo by Liz Corry.
*apologies to anyone not a fan of Star Wars and to everyone for the bad pun.
RBC helps out Jersey Zoo’s own RBCs (red-billed choughs)
On 9th June a team from the Royal Bank of Canada volunteered their time at Jersey Zoo to help with the choughs.
Team RBC: The Royal Bank of Canada staff who volunteered their time for the Red-Billed Choughs. Photo by Gisele Anno.
They were set the task to weed the borders outside the display aviary and plant it up to look like chough habitat found on the north coast. Species such as foxglove, red campion, bladder campion, knapweed, lady’s bedstraw, birds foot trefoil and heather were added. Most of the plants were coming to the end of their flowering period, but they will grow back next year.
RBC volunteers weeding the borders outside the chough aviary at Jersey Zoo. Photo by Gisele Anno.
Gorse bushes translocated from the old green lizard enclosure into the aviary when the choughs first moved in, have now spread to the outside. Volunteers made sure these young growths received a bit of TLC to encourage them to grow.
RBC volunteers working hard on the native species border. Photo by Gisele Anno
At the end of a hard day’s work they were treated to a talk from Glyn about Birds On The Edge, the choughs, and the reason why conserving coastal farmland is important.
On top of volunteering their time, the RBC have donated money to help rodent proof the release aviary and repair netting damage. For which we and the choughs are extremely grateful.
LIVE Teaching through nature
The choughs participated once again with Alderney Wildlife Trust‘s LIVE Teaching Through Nature schools programme. Their blogging skills almost as good as their flying skills if I may say so myself. The online paid programme offers schools the opportunity to bring nature into their classrooms by utilising live streams of Alderney’s seabirds, videos and blogs from Durrell and the choughs in Jersey, and the occasional live chat with field staff.
This project links directly to the key stage 1 & 2 curriculum, and is an effective way of teaching science and literacy skills, and encouraging pupil creativity and confidence. Feedback from our two week takeover in June was yet again positive hopefully inspiring some young conservationists along the way.
Jersey’s coastal habitat was home to spring lambs, wild flowers, and baby choughs this month. Here is what the choughs got up to. Or, as we can now call them, what the award-winning choughs got up to!
May the 4th be with you
On May the 4th the first of the three eggs in Issy and Tristan’s nest hatched. Staff were naturally excited and considering the date, the geeks amongst us (i.e. everyone), started putting bids in for Star Wars related names for the clutch.
Chough eggs hatch sequentially so we expected it to take a few days. However, the days passed and it became clear that this would be the only egg to hatch.
Han Solo was duly christened.
The parents were keen to remove one of the failed eggs. The other was left in the nest for quite sometime.
With only one chick to care for, Han Solo was well fed and grew steadily day by day.
Breeding in the wild
This year’s wall planner had a rather colourful month in store with various predicted hatch dates starred and scribbled in colour-coded marker. First off the blocks were to be Red and Dingle (hand-reared) who raised their first chicks last year. This year’s eggs were due to hatch around the first week in May. A change in Red‘s behaviour on 4th May suggested the eggs might have started hatching. Instead of waiting for the cue from Dingle, she was already waiting at the aviary for food in the morning. As soon as she picked up a mouthful of mealworms she zoomed back to her nest.
We asked Kevin le Herissier, responsible for ‘their’ building (Ronez naively still believe that the buildings are theirs not the choughs’), to check the nest the following week. This was to allow time for the entire clutch to hatch and so that the parents were not as sensitive to disturbance.
To our bemusement the photo he sent back was of a perfect nest containing four eggs.
Red and Dingle’s nest early in May. Photo by Kevin le Herissier
A follow up check on the 19th also found four eggs. Guess what was found when the nest was checked for a third time on the 31st? Sadly, not a case of third time lucky. Still four eggs. Under license by the States of Jersey, these eggs were candled in the nest to find answers to what had happened, why they hadn’t hatched. One egg had failed during embryonic development while the others looked like they contained almost fully developed chicks. The eggs were returned to the nest.
New nest-site discovered
Student John Harding and Ronez operational assistant Toby Cabaret checked on the nests in the quarry on the 19th. Armed with a GoPro and a very long pole they checked nest-boxes and known nest sites. One of the nest-boxes we fitted in the quarry in 2015 had nesting material in it. What flew out wasn’t a chough though. It was a kestrel!
Most of the nests were just centimetres out of reach of the pole and suspiciously quiet. The team did, however, spot a female on a nest in a building not previously used by the choughs. With no wish to disturb her the nest was left alone. We now have the task of trying to work out which pair this nest belongs to.
A neighbouring building was also found to have a nest. This one didn’t have a female on it, but from the begging noises it was clear there were at least two chicks in there. Again this is a new site and new pairing.
This video shows Toby and John trying to use the GoPro to check the cheeping nest. They didn’t realise at the time how close they were to the nest. You can see the chicks.
They look extremely young. Normally we would avoid disturbing a nest at this age. From our calculations we expected any chicks to be a few days older. From their begging they look strong.
All nest checks are done under license from the States of Jersey.
Chick ringing and revelations
On the 31st we returned to the nest sites. This time with Channel Island ringer Dave Buxton in case the chicks were old enough to fit with leg rings. We were also armed with a new piece of equipment…a USB endoscope camera. It doesn’t provide HD images like the GoPro. However, it is equipped with LED lights and a lot more manoeuvrable (and only cost £25).
Toby Cabaret checking a chough nest with the Potensic endoscope. Photo by Liz Corry.
Three chicks could be seen with the endoscope plugged into a smartphone. Photo by Liz Corry.
Due to health and safety concerns, two nest-sites were out of bounds. We were able to check the nest with the cheeping chicks. This time eerily silent, although it was clear from the endoscope image that there were three bills. They still had pin feathers on their heads and from their size they looked no more than two weeks old. Too young to fit rings.
Before leaving the building John and Toby went a checked the next floor up on a hunch that there could be something. They were right! They found a nest tucked away behind girders.
Spot the nest? Photo by Liz Corry.
Despite a grainy image, the colour and shape of a bill could be seen and possibly a second body. The image below is a snapshot from the endoscope. The image is less clear than in realtime. You will be forgiven if you can’t spot the head of a chick.
Screen grab of endoscope view in nest showing the pale bill of a chick (far right). Photo by Liz Corry.
Whilst checking this nest Kevin and Bean flew in and appeared slightly aggrieved that we had discovered their little secret. The disappointment of the chicks once again being too young to ring was quickly overshadowed by this news. Bean is one of our hand-reared females released as a juvenile in 2014 and now, three years later, rearing chicks of her own!
We received several reports of choughs out and about this month from members of the public. Of interest was a report of a pair from Tabor Park, St Brelade. They had been seen on the allotments, but flown before leg rings could be read. Five days later another report came in of a chough calling at the desalination plant by Corbiere.
We have radio-tracked choughs to the south-west before in 2014 and 2015. Since then there have been a handful of sightings around Gorselands, Le Creux and Red Houses.
Choughs on the move. Photo by Liz Corry.
Regular chough watchers Mick Dryden, Tony Paintin, and Piers Sangan reported choughs at Crabbé, Île Agois, and Grosnez during the day. We assume these are the sub-adults and non-breeders who don’t have commitments at the quarry. Without leg ring records we can’t be sure.
Grosnez to Plémont with Sorel point in the far distance: areas visited by the choughs this month. Photo by Liz Corry.
Personality research with Nottingham Trent University
Guille Mayor arrived this month to start his MSc research looking at personality traits in released choughs. He is trying to see if personality relates to dispersal distances and success in the wild. Part of his work will involve behavioural observation at the release aviary and how individuals react to a novel object.
The trickier part of his study requires him to find where the choughs go each day. He obviously likes a challenge since only three in 34 have radio tracking devices and Guille is on a bicycle. If you do spot a chough away from Sorel please as also let us know. Send an email, call 01534 860059, or post on Jersey Wildlife Facebook page. Location, date, time, and, if possible, leg rings need including.
British and Irish Association of Zoos and Aquariums (BIAZA) held their annual awards at The Deep in Hull this month. Durrell had entered four categories and came away with three gold and one silver. We are delighted to announce that the return of choughs to Jersey was awarded gold in the conservation category.
April started on a tragic low note progressing, the only way it could, into a steady crescendo to a high and hopeful cadence. In fact, April started as it always does with April Fool’s Day. So when an email entitled ‘chough vs. peregrine’ was opened on the 2nd, wishful thinking wanted to dismiss this as a delayed prank.
The email was from Mick Dryden and Romano da Costa, two of Jersey’s top birders, who had been out at Sorel Point doing a migration count.
Mick described observing “an immature peregrine fly onto the cliff with a black bird in its talons. We both thought it was the remains of a chough. The peregrine was hassled by gulls and flew off west, but dropped the bird in the sea where a greater black-backed gull performed the last rites. I had the scope on it distantly and think I could see red legs very briefly, possibly also a ring which may have been green. So if you are short of a chough, you know why!”
For legal reasons we would like to state that the peregrine flying over Sorel in this photo is innocent until proven guilty. Photo by Liz Corry.
The email was read at home after spending the day out at Sorel monitoring seemingly very content choughs. In fact, it was the first day the choughs had been seen carrying nesting material. Not only that, but the first bird spotted carrying material was Pyrrho, a female of only two years of age. A potential new breeder!
Pyrrho carrying nesting material, but to where? Photo by Liz Corry
Added excitement had come when a large group of choughs spent the day hanging out around the section of cliffs where we fitted a nest-box in 2014. Birds were seen to come and go from the box. Could one of them be adding nesting material?
The acrobatic aerial displays they were putting on, launching themselves off the cliff face were a joy to watch.
Acrobatic choughs at Sorel. Photo by Liz Corry.
To get home and find out that one of them had most likely been skewered by talons, plucked apart, and unceremoniously dropped in the sea, only to be further shredded into oblivion, was a little disorientating to say the least.
The choughs have started changing their daily patterns most likely as a result of the breeding season. Pairs have been spending less time near the aviary, some turning up late. In the case of Lee and Caûvette, the notorious absentees, they did the opposite and started turning up for both morning and afternoon feeds.
Lee and Caûvette (centre) have started returning for the supplemental feeds suggesting they might be nesting nearby. Photo by Liz Corry.
Once the choughs had grabbed their free handouts they would swiftly return to their business of either nest-building and/or wild foraging. There has been an abundance of leatherjackets and other grubs in the fields this month keeping them fuelled for the day. It, therefore, didn’t raise alarm bells when only 32 of the 35 choughs were counted on the morning Mick described the attack.
A leatherjacket larvae unearthed and being tenderised before adding to the chough menu of the day. Photo by Liz Corry.
The following day was spent staking out Sorel ticking names off the chough register. Mick’s description of a green ring turned out to be a red herring when, after a few hours, all the choughs sporting green rings were alive and well. This is included a breeding male, Pale Green, a wild-hatched chick, and hand-reared Bean. Never believe parents when they say they don’t have a favourite!
Ticking off the chough register each day isn’t easy with birds like Helier whose broken green ring has slipped over the blue one. Photo by Liz Corry.
By the end of the day the identity of two birds still remained unconfirmed. Hayle and Yarila, both hatched at Paradise Park last year, and wearing almost identical leg rings. One blue and white striped. One black and white striped. Out in the field with the glare of the sun, the white-out of the fog (we had both), and the desperation in your mind, it is very difficult to determine the difference between the two rings.
Attempts to get a clearer view of leg rings by feeding choughs outside of the aviary failed when the sea fog rolled in. Photo by Liz Corry.
Even when Hayle’s radio transmitter was tracked down to the cliff face where the peregrine attack occurred your mind wants to add the element of doubt. What if she just shed the transmitter there and is merrily foraging in the fields? Sea fog and sheer cliffs prevented the recovery of the transmitter.
Somewhere beyond the gorse lies a cliff face and a lost radio transmitter. Photo by Liz Corry.
Not that it would have told us anything other than Hayle was no longer attached to it. Three days later, with a total count of 34 birds, none of which wore a blue and white striped ring, we reluctantly concluded Hayle wasn’t attached to anything in this world.
And now for the steady crescendo…
Breeding season update
The chough group did not spend long mourning the loss of their friend. Priorities were focused around breeding and collecting nest-liner courtesy of the sheep. We were able to ascertain a few new potential breeding pairs thanks to this. We have also noticed a few unexpected couplings based on mutual preening and feeding behaviour.
The most intriguing of which is a new trio. Pyrrho has teamed up with one of last year’s wild-hatched chicks. At only 11 months old (someone call Social Services) he would seem a bit young for Pyrrho. The young male is still very close to his sister and the three are often spotted flying to the quarry together. It would be unusual if this trio were to produce anything other than a nest this year.
Wild-hatched siblings Pink-Orange (male) and Black-Orange (female) have teamed up with Pyrrho this breeding season. Photo by Liz Corry.
We already have a trio of Dusty, the original wild-hatched chick, and two females Egg and Chickay. Both females have been building nests; however, Dusty pays more attention to Egg and we believe she has started incubating. Last year, when this trio formed, they did not get beyond the nest-building stage so Egg’s behaviour is very encouraging.
Egg collecting nesting material from the quarry for her nest with Dusty. Photo by Liz Corry.
Chickay, a hand-reared chick, collecting nesting material from the quarry. Photo by Liz Corry.
These were not the only choughs to be busy nest building. We have seen five pairs visiting the sheep pens to collect wool. Not straight from the sheep’s backs I hasten to add.
Choughs busy collecting wool to line their nests at Sorel. Photo by Liz Corry.
The choughs have been making the most of the sheep’s confinement to the aviary field this month. Photo by Liz Corry.
We have struggled to assign each pair to a nest site. With so many choughs using the quarry now simply for recreation it is difficult to know who is who and what they are up to. Working with quarry staff, we believe we have double the number of nest sites compared to last year.
A tell-tale clue as to where this pair has chosen to nest is in the fact that they are covered in quarry rock dust. Photo by Liz Corry.
We started to notice behaviour in the last two week’s of April that suggested some of the females had started incubating. It has not been as clear-cut as in previous years making it trickier to predict hatch dates. Bets aside it is certain that May will be a productive month.
Health updates and post-release care
Monthly faecal screenings showed the parasite count in the flock to be lower than last month. It would be a statistical miracle to assume that the entire flock was represented equally within a sample. However, taking into account fewer observations of sneezing birds it appears to be a fair reflection of the group’s general parasite loads. The reduction was possibly helped by the absence of Hayle who had been seen sneezing and wheezing a few days before she encountered the peregrine.
One of the wild-hatched choughs was seen to have something wrapped around her foot on 17th April. We monitored her closely and it soon became clear the offending material was not going to come off unaided. We are permitted to catch up and handle wild-hatched choughs for welfare reasons under our license granted by the States of Jersey. Therefore, to avoid any potential problems with blood circulation in the future, we caught her up and snipped the thread free.
PP003 had to be caught up in the release aviary to remove tangled thread from her foot. Photo by Glyn Young.
At the same time as attempting to catch this bird (it took several days) we noticed Bean had managed to wedge one of her digits up into her plastic rings. We had hoped that she might manage to wiggle it free or break the plastic since the rings are now quite old. She didn’t comply so she too was caught up.
We had to be very careful with Bean and the rest of the group when it came to entrapment. Not for legal reasons. We did not want to inflict any unnecessary stress on any of the egg-laying females. We had suspected Bean could be one such female since her and her partner have collected nesting material. Once in the hand her brood patch was a big giveaway. Her foot was quickly freed, replacement rings fitted, and she was allowed to return to her nest within minutes of being trapped in the aviary.
Yarila preened out her broken tail feather this month complete with radio transmitter. Photo by Liz Corry.
Yarila conveniently preened out her radio-transmitter on 24th April whilst sat on the aviary roof. At the start of the month one of her middle tail feathers was sticking up at a right angle to the other eleven. Obviously loose, but hanging on to something. In fact we noticed it the day after the peregrine incident. Coincidence?
Looking at the recovered transmitter it is clear that the loose feather was still holding on by a thread to the base of the transmitter. The other central tail feather, which gets glued to the transmitter, has snapped off and detached from the base of the transmitter hence the tag falling off. This is the first time we have seen this with our choughs.
Jersey Zoo breeding pairs
CI Fire & Security Ltd kindly installed a new wireless system at the chough breeding aviaries this month to allow staff to monitor all three nests. CI Fire & Security Ltd have previously installed cameras at Durrell in the bear and orang enclosures. Whilst seemingly not as challenging as designing an orang-utan-proof camera, the chough-cams proved trickier than expected. Two of the three cameras were up and running in March. The third, in Issy and Tristan’s aviary where we hope the pair will parent rear took a bit longer, but finally went online on 13th April. At which point we discovered she was sitting on three eggs!
Keepers had found an egg on the floor near to the nest-box earlier in the week. We don’t know why it was on the floor. We do know that she has not laid anymore eggs since the day the camera went online. An unusually low clutch number for Issy, but at least she has eggs and is looking after them.
Now we have the nest-camera we can closely monitor the progress of these eggs, any subsequent chicks and support the parents along the way if needed. We expect the eggs to hatch at the start of May with a view to release healthy fledged chicks in the summer.
Simon Inman’s fundraising last month has managed to raise £140.73. This has help pay for the new wireless nest-camera in Issy and Tristan‘s aviary. Simon’s sponsored skydive is in summer so there is still time to donate.
Our other two breeding pairs appear to be dawdling. It took them a while to start building nests and now they just don’t want to stop. This footage of Denzel and his partner was captured on 25th April…
It is a little harder to tell what Gwinny and Lucifer are up to thanks to Gwinny inadvertently repositioning the camera.
For our tame bird Gianna she has to sit and wait for the likes of Gwinny to start egg-laying. We can then give Gianna a dummy egg to stimulate her to start laying her own (infertile) eggs. When the time is right we can swap eggs or chicks for foster rearing purposes. Timing is partly influenced by the behaviour of the pairs especially Lucifer who has a tendency to dislike eggs appearing in his nest box. We’re not exactly sure what he expects to use the nest for.
Gianna taking nesting material for her foster nest. Photo by Liz Corry.
Gianna completed her nest and is now waiting for the cue from keepers to start laying eggs. Photo by Liz Corry.