Choughs fly again in Jersey!

Well, Wednesday afternoon (28th August) was rather exciting/stressful. We planned to open the shutters at the Sorel aviary to the outside world for 30 minutes at 1700. This first step should be considered part of the training for the birds rather than an ‘official’ release. The idea is that the birds get a few minutes outside each day with the access time lengthened slowly until the birds are left completely at liberty. While the birds may or may not choose to go out of the aviary they will be called in again after 30 minutes and shut inside again.

This soft-release process will be repeated daily until late-September when the birds may remain at liberty unless specifically called back in (they will be fed daily and watched closely for the foreseeable future whatever happens). The first opening of the hatches was not made into an event, mostly because something could have gone wrong or, much more likely, they would not actually go out at all on the first day.

Release Day 1 (28th August)

The first chough out (PG). 28-8-2013. Photo by Annette LoweFirst flight! Photo by Rick Jones, DurrellThe shutters were duly opened at 1700 and we had 30 minutes of ‘freedom’ and three birds wandered outside. One chough flew round a bit but not far from aviary and came in when called. Not a bad start! The birds behaved very well and the value of training and Liz’s hard work were obvious. Target platforms have been put up outside of the aviary to give the birds their own and recognisable perching spots outside the aviary.

Listen to BBC Radio Jersey’s Tori Orchard interview with Glyn Young on the morning of the first ‘release’ (it’s also No 7 in the series of Tori’s interviews here).

Day 2 (29th August)

The ‘release’ process was repeated today when four birds ventured outside including ‘senior pair’ MV and PG. One bird, RD, failed to grasp the idea of the entrances and failed to find its way back inside and spent all night on the aviary roof before going back inside early on Friday morning.

Day 3 (30th August) – the day we discovered that choughs have minds of their own!

The senior pair (well, they are two years old) ventured rather further afield today and decided to explore nearby Ronez Quarry.  There was a heart-in-mouth moment when we watched a peregrine attack the pair but they recognised the threat and, in mid-air, on the longest flight of their lives fought it off – during the attack the falcon grabbed one of the chough pair by the legs but let go pretty quickly. One chough went to ground to avoid the persistent falcon but the pair were quickly re-united and seemed unfazed. That’s the first peregrine encounter out the way, let’s hope that any more have the same outcome.

Choughs return to Jersey. 1st September 2013. Photo by Colin StevensonWhile we can observe the choughs directly, allowing us to follow their activities and check on their wellbeing, the radio transmitters allow us to track the choughs at all times. On Friday the pair moved around confidently, foraged on the ground, displayed, flew out over the sea, perched on a woodpile and generally behaved like ‘wild’ choughs. We quickly learned that the choughs and the local carrion crows just ignore each other now that they can really meet.

Choughs on Jersey's coast again. Photo by Colin StevensonThe radio tracking team went into action and have, over the weekend, recorded the pair’s locations following a research protocol devised in advance. Having said that, the pair have at times been very visible and have appeared over Sorel Point and around the car park. Often they call loudly.

On Friday night the now christened Ronez 2 slept inside one of the quarry’s conveyor belts! They were up early Saturday morning and have continued to put on a good show. Never once have they gone near the aviary even though we know they’ve been able to see it when flying up high. The pair have once more encountered falcons and were seen to actively mob them.

Chough near Sorel Point. Photo by Liz CorryThe free-flying pair seems quite happy in and around the quarry and slept again in or near the conveyor. Wild choughs regularly live in quarries, including in North Wales, the ancestral home of our birds (see video of choughs in a quarry here). There is water in Ronez Quarry, secure roost sites and, hopefully, lots of foraging opportunities and respect from the quarry owners and personnel. The pair has been seen regularly on the grass at Sorel Point. Even with the Ronez 2 out and about, we will continue the slower soft-release of the other five birds but are wary that they have temporarily lost the presence of their senior members. Well, lost them unless they go and re-join them in the quarry!

Red-billed choughs near Sorel Point. September 2013. Photo by Liz CorryNow that there are birds out on the coast, please don’t hesitate to send in your sightings. Check here for details.

We are very grateful to the team-members who have assisted us in observing the release. Alison and Ray Hales from Paradise Park (Operation Chough) have been watching the birds with us all weekend. Mike Stentiford, the project’s staunchest supporter from when it was first imagined was there for the first opening. We must also give sincere thanks to Ronez Quarry who may get to see a lot of the choughs and of us!

 

 

 

Chough report: July 2013

Report by Liz Corry

Sorel fog, July 2013. Photo by Liz CorryChoughs at Sorel

The Sorel choughs have had an ‘eventful’ month, no doubt further building their anticipation for release.

Sunbathing choughs. July 2013. Photo by Liz CorryFirstly they have witnessed a variety of impressive weather fronts. Mystical rolling sea fogs, scorching heat devoid of any cooling breeze, and some impressive thunderstorms. In an ‘exposed’ aviary such as the one at Sorel there is always the worry that the birds do not have enough appropriate shelter or shade. It helps that choughs are a hardy species. More importantly they are always being monitored by keepers and the aviary has been designed with shelter points in mind. A bit like dogs, birds will pant and stand open-mouthed when extremely hot. Fortunately without the slobbering. Extra drinking and bathing water was provided when necessary. The fog didn’t really cause any problems for the birds and the drop in humidity was probably a welcome relief. The birds may have also appreciated the blanket of secrecy provided by the fog as they had very few visitors.

Rodent damage at Sorel aviary. July 2013. Photo by Liz CorryWhile the birds have had only a few non-human visitors besides dogs out on walks, there has, however, been an increase in rodent activity in and around the aviary. This was expected as the months go by and seasons change. Something, most likely a field mouse, has been testing the durability of the aviary netting.

In response to the rodent visitors, a specialised rodent-deterrent paint was applied to the netting around the perimeter of the aviary. The idea is that the rodent is put off from chewing because of the nasty taste. Normally the netting is pre-soaked before being used. Durrell has recently started testing the effectiveness and the aviary at Sorel became the most recent test subject. Unfortunately it appears Sorel mice do not object to the taste. On the plus side Sorel mice are not very adventurous/intuitive and have only focused on one tiny corner. Keepers seem to be winning this battle!

The pair of peregrines that patrol the Sorel-Crabbé cliffs started moving inland towards the end of July. They have been spotted close the aviary on a few occasions, but don’t seem to show an interest in the choughs. Their presence is likely due to the increase in stock doves foraging in the neighbouring fields. As long as the peregrines have plenty of existing food resources we hope they will not need to add soon-to-be-released chough to their menu.

Radio transmitters and veterinary health checks

Moulting process in chough tail feathers. New central feathers growing in, outer ones still to drop. July 2013. Photo by Liz CorryOn 9th July three of the choughs were caught up to look at their tail feathers and assess what stage of their moult they were at. We wanted to look at the three youngsters because one of them was the first to drop its radio transmitter, i.e. it had moulted the central tail feathers. The other two never had a transmitter and would, therefore, provide an interesting comparison.

The chosen three were isolated from the group by calling them down for food and encouraging them into a section of the aviary sealed off by closing hatches. They were then caught in hand-nets by Durrell bird keepers who don’t work at Sorel  (the choice of staff was to avoid any negative association the birds might develop if Sorel keepers were to do it). In the safety of the keeper porch a quick assessment of their moult score for tail and primary (wing) feathers was made.

Attaching radio transmitter. July 2013. Photo by Liz CorryAll choughs moult their tail feathers starting from the centre and working outwards. They start growing new tail feathers at the same time as their primaries (wing feathers) but complete the tail moult before the primaries are complete. All three of our choughs were at a similar stage in that only their central four tail feathers had started moulting. This meant that they definitely were not ready for new transmitters to be attached, but could well be in a few weeks.

A second catch-up was carried out on the 26th when all the birds needed to be given an injection of ivomectin to protect against possible gapeworm infections. Due to timing constraints only four could be caught up. The remaining three were caught up on the 30th.

In the first group, which happened to be all the older juveniles, only one was ready for a radio transmitter. The others were still moulting through the central tail feathers. From the second group, two were ready and had transmitters attached. The remaining birds without transmitters will be caught up again towards the end of August by which time they should have new, stronger, tail feathers.

Whilst in the hand there was the opportunity for a quick general health check of feet, eyes and beak. All looked good and with no obvious sign of a gapeworm infection. There has been one female that developed a slight limp. Her leg was looked at but there was no sign of injury or bumblefoot and the vet was happy with her condition.

Radio tracking team

After advertising through this website, via social media and on Channel TV we have managed to fill the positions for radio-tracking assistants. The team of three are all local to the Island and bring with them a range of skills and experiences beneficial to the project. Training will begin in August prior to the imminent release of the choughs.

Behavioural Observations

Jess Maxwell has had to finish her observations early due to other work commitments. We are trying to carry on with this study up until, and possibly after, the birds’ release. Myles Lamont, Durrell student, is helping out with these until he leaves to join Durrell’s Mauritius programme in mid-August.

Habitat management at Sorel

Mowing field by Sorel aviary. July 2013. Photo by Liz CorryThere have been several different activities going on at Sorel over the last month benefitting the BOTE project. At the start of the month the farmer and his team were out on the NTJ fields harvesting potatoes. This seemed to provide much entertainment for the choughs as they spent less time watching the coastline and more on the farm workers. My guess is they were eyeing up the soil for insects and probably became insanely jealous.

Aaron, the shepherd (CS Conservation), has been very busy shearing the sheep which of course involves the onerous task of rounding them up first. The sheep range over both sides of Mourier Valley so the task takes several days and two very energetic Border collies. The choughs were a little on edge whenever a small flock of sheep would run past, but who wouldn’t be. On the whole, however, they paid little attention to what was going on.

A team from the Government run Back to Work scheme spent several days erecting sheep fencing around the aviary and the field perimeter. Back to Work is a voluntary scheme for qualified jobseekers which aims to provide them with skills beneficial for the workplace. They teamed up with the National Trust to work on several conservation projects including this one at Sorel. The population of sheep at Sorel has grown over the years and they now need to expand their grazing sites. Now that this field has been securely fenced the sheep can be moved in when needs be.

Once the fencing was in place Aaron set to work cutting back the dry, long grass. Great care was taken in using the tractor so close to the aviary. The design of the aviary allows the birds to ‘escape’ to either end depending on where the tractor/disturbance is. Once cut, a team of volunteers organised by the NTJ went up to the site and raked the cuttings into lines. This allowed Aaron to go back at a later date and quickly gather and remove the hay.

Bracken clearance by aviary. July 2013. Photo by Liz CorryOn a less intensive scale, albeit very laborious, work has begun to remove bracken on the embankment that runs alongside the aviary. This will benefit the choughs in that more ground will be exposed for foraging and obstructions from in front of the release hatches have been removed to encourage bird movement back and forth.

Neil Singleton, chough field assistant, kindly volunteered his time to help me pull out the bracken and stinging nettles. Due to the vast quantity of Slow worm by Sorel aviary. July 2013. Photo by Liz Corrybracken, the green waste was taken off site and burnt on Durrell’s fire pit. We have unearthed some interesting finds including a crapaud (a common toad for non-Jersey readers), a slow worm, and sadly a very dead green lizard. The removal of the bracken has also uncovered the hedgerow saplings planted in previous years by NTJ volunteers: a lot had suffered from being smothered by the bracken but some still stand firm and will hopefully continue growing. This work is ongoing.

 

Chough report: June 2013

Choughs at Sorel aviary, June 2013. Photo by Liz CorryReport by Liz Corry

Choughs at Sorel

Choughs responding to the ‘lunchtime’ whistle call and flying to only the target areas. Photo by Liz CorryAs a result of the birds moulting, an opportunity to release all seven birds has now arisen. This has also meant that there is no longer a need to keep the two ‘non-radio tagged’ birds isolated from the others. When they were remixed, the young pair, Orange and Red, reunited straight away in a mad flurry of preening.

As the days went by it started to become evident that the two pairs in the flock had each claimed an area of the aviary. Neither pair particularly defends this territory, but they do show dominance over food during the training sessions. For example, Green and Mauve will push the others off the tables in the poly-tunnel when food is put down. Yet they will hesitate when flying on command into the ‘shed’ area where Orange and Red have been carrying nesting material.

Choughs responding to the ‘lunchtime’ whistle call and flying to only the target areas. Photo by Liz CorryThis pairing behaviour makes it problematic for the keepers as the birds are not being rewarded for carrying out the correct behaviour, i.e. flying to the target area on whistle. It also means that the scales need to be moved around the aviary in order to try and get body weights on all seven of the birds.

By the end of the month all seven choughs had, through moulting, dropped their radio transmitters. The transmitters have now been sent back to Biotrack in the UK to have new batteries fitted to permit at least six months tracking time after the birds are released.

Choughs at Durrell

The 2013 breeding season has now come to a close as both breeding pairs have started moulting. The pairs will be moved back up to the display aviary next month and mix with the non-breeding birds.Replica chough egg (left) used in clutch manipulation practices compared to the real egg (right). Photo by Liz Corry

The egg recovered from this year’ failed clutch was ‘blown’ by keepers. This is a technique whereby the contents are carefully removed and the shell sterilised using a hyper-dermic needle and syringe. The egg will be kept for educational purposes.

George sunbathing in display aviary. Photo by Liz CorryGianna’s prima donna tendencies shone through this month when keepers moved George into the display aviary. At first Gianna was wary of him and sulked when keepers paid George attention and, since he was still being medicated, this happened quite a bit. George himself was visibly happier to be out of the Vet Centre. He was washing, sunbathing, and flying around all within the first few hours of being in the aviary.

For a while Gianna decided to take the approach of ‘if you can’t beat them, join them’. It seemed the perfect pairing. She then opted very quickly for the ‘beat them’ approach and ferociously attacked George. Thankfully members of the public witnessed this and quickly reported it to a member of staff. The keepers were then able to intervene and separate the two. George was visibly shaken but luckily only suffered some bruising. George, once again on his own, will be moved to one of the breeding aviaries once the pairs have been moved out.

The choughs enjoy a sunny day at Sorel. Photo by Liz Corry

 

 

 

Out and about with Arthur the Chough

Arthur awaits the Itex walkers 2013. Photo by Sarah NugentAs we wait patiently for the trial release, and our seven choughs get ready in their north coast aviary, one chough has been seen out and about in Jersey recently. Arthur the Chough recently spent some quality time on our coasts. First he looked in on the 2013 Itex walk on 22nd June. Not a natural walker, Arthur opted for the shorter Lieutenant-Governor’s Walk (a mere 13 miles) encouraging walkers from near Devil’s Hole before flying down to the end of Arthur and the Lt. Governor 2013. Photo by Sarah Nugentthis walk at La Braye in St Ouen’s Bay. This component of the annual walk took walkers, and indeed Arthur, through chough habitat and very close to the aviary. I hope the walkers enjoyed the stunning coastline and considered how it may be further enhanced in the future thanks to Birds On The Edge. The weather, sadly, early in the morning, was actually not too conducive to enjoying the countryside but Arthur was able to cheer up the hardy and even met the Lieutenant-Governor, General Sir John McColl.

Arthur assists Badlabecques at the Sunset Concert 2013. Photo by Sarah NugentArthur made a further guest appearance at the National Trust’s Sunset Concerts on 28th June. On this lovely evening, Arthur helped out during the performance by our friends Badlabecques. As last year’s concert raised the money needed for the release aviary it was only fair that Arthur should be on hand to thank everyone and spread the message about Birds On The Edge and his friends up at Sorel. Arthur was doubly proud to be there to hear Badlabecques sing the project’s ‘own’ song “Ma Bouaîs’sie” for the first time in public.

Arthur will be visiting the Island’s primary schools during the year, he has visited four so far and will be at another this week. He will be in the Wildlife Park for Durrell Days (13-14 July) and is also headlining at Jersey Live this year (31st August-1st September). Look out for Arthur, but please don’t confuse him with other corvids (look here for hints), and carry some cranefly larvae as a handful might make him a friend for life! He now has an egg to look after and carries a lunch box containing ants!

Cornwall’s choughs – the dramas continue

The Lizard female. Photo by Bob Sharples www.bobsharplesphotography.co.ukWe recently relayed dramatic goings on in the lives of Cornwall’s choughs. Well, Cornish Choughs report that there have been further dramas from the Lizard:

“After reporting a few weeks ago that the male of the Lizard pair of choughs had gone, we are sad to say that his mate has also disappeared.  For just over a week the female continued to feed her two chicks with the help of the ‘usurper’ male, but she then vanished and we can only surmise she pined for her lost mate and died.  It is not unheard of for this to happen where there has been such a strong and long bond between two birds. She safely fledged 44 chicks over her lifetime, and some of those birds have gone on to raise families of their own.  Quite an achievement in the bird world and her place in Cornish history alongside her mate is assured.

There is a happier side to this story though as the incoming male is continuing to feed her two chicks.  They are doing well and are due to fledge next week.”

Updated 3rd July. From Cornish Choughs: “After a bewildering breeding season on Southerly Point with the original pioneering pair vanishing, we are pleased to announce their two chicks have fledged!  This has been made possible by the other male chough who continued to feed the young.  Amazing! Chough watcher Paul Gillard made a video of one of the new chough families in West Cornwall”.

 

 

Volunteer field assistants required – radio-tracking the red-billed choughs

Jess, chough field assistant, radio-tracking at Sorel. Photo by Liz CorryBackground

Birds On The Edge needs your help. We will be releasing the small group of young choughs to the north coast of Jersey very soon now. This is a trial release and each of the birds will be radio-tracked and monitored closely for a period of six months (see our monthly reports here).

The position

Choughs in the Sorel aviary. Liz Corry. April 2013 We require the support of keen volunteers to work alongside our Field Manager to carry out this radio-tracking and monitoring. So, we are looking for people who are able to commit to up to six months starting in early August 2013 and ending no later than 31st January 2013, although the end date depends a little on the birds themselves.

Volunteer activities will be focused around intensively tracking and, if necessary, searching for released choughs and recording basic behavioural data in the field. Training will be given in radio-tracking, habitat assessment and understanding chough behaviour.  Volunteers will also be responsible for entering some of the data collected into the field database.

Le Don Paton. Photo by Mick DrydenRequirements

Applicants will need to:

  • Have a background in biological sciences
  • Be happy to work outdoors and have some previous birdwatching experience
  • Have flexibility, commitment and determination to work, under sometimes uncomfortable or frustrating conditions, combined with good physical fitness
  • Provide careful attention to data recording
  • Be able to commit 18 hours per week for 6 months
  • Be resident in Jersey
  • Have transport within Jersey, personal equipment and insurance but the project will assist with money for petrol used if the birds need following.

This is the ideal opportunity for someone looking for practical conservation experience working with this very exciting re-introduction project for such a highly charismatic bird.

If you wish to apply, please contact volunteer@durrell.org

Closing date for applications: Friday 19th July 2013

Drama among Cornwall’s wild choughs

From Claire Mucklow, RSPB’s Cornwall Projects Manager

Cornish chough. Photo by Bob Sharples www.bobsharplesphotography.co.ukThe last week has been one of both tremendous highs and lows for the chough team in Cornwall. They were very sad to have to report the loss of the wonderful male chough from Southerly Point on the Lizard. Just over a week ago a volunteer witnessed two choughs locked in combat for the most part of the day, and it appears that the new younger bird has ousted and possibly killed the older male. He may not be dead but he has certainly been usurped. Claire says “I always joke ‘they will live forever’ when people ask me how long the pair at Southerly Point will be around, but sadly choughs are not invincible and nature in all its rawness has won the day. An end of an era, and the loss of a very special bird”.

What a legacy that chough and his mate have left Cornwall with though. Since they returned in 2001 they have brought so much joy to those lucky enough to spend time with them and a real sense of Cornish pride enveloped them. The pair together raised 44 chicks and many of those birds have gone on to breed themselves, securing a future for choughs in Cornwall. Proper job!

But, there is a happier, and unexpected, twist to this tale. The new male, a bird often seen in the company of the Lizard pair, has adopted the old male’s new chicks – extraordinary as normally a bird would try to kill any chicks that were not his. This is new behaviour, possibly not previously recorded for choughs. The female having invested so much time and energy in her new brood has accepted this new male and together they are feeding her two chicks, which are around two weeks old. Here’s hoping the female and her new mate will live for many a year.

There is further news of chicks in Cornwall where there are already chough fledglings this season; five more youngsters took to the skies last week in Penwith. The crazy weather has really affected this year’s breeding season and, with six weeks between first and last broods, the last chicks will not fledge until early July. The total number of young for this season so far is 16, two broods of five, and three broods of two. There are a further three pairs of choughs that have shown signs of breeding but they are too young this year.

Follow news of Cornwall’s choughs on the project website here and on Twitter at @cornishchoughs. Find where to watch wild Cornish choughs here

Chough report: May 2013

Red-billed chough at Sorel. May 2013. Photo by Andrew Koester

Report by Liz Corry

Choughs at Sorel

Pre-release training

Choughs on target boards. May 2013. Photo by Liz CorryTraining this month experienced another learning curve for both choughs and keepers. During training sessions the birds were becoming sluggish and/or lacked motivation. Keepers noticed that with the change in season more and more insects were starting to emerge. The choughs were spending more time probing the ground between sessions and we quickly realised that the birds were just not hungry enough to bother finding out what the whistling keeper was bringing them. With food rations imposed the motivation returned!

Choughs on target boards. May 2013. Photo by Liz CorryAt the same time another behavioural issue arose. As the group becomes more settled in the aviary their personalities start to show and social structures form. When training first began every bird was in the same position. Once they understood what was expected of them and what reward they would receive they would flock to the target boards. Now with a pecking order established (pun fully intended) the dominant ones make sure that the shy ones wait their turn. Which means either very little or no reward at all for some birds and the desired behaviour is not reinforced. To break this pattern more target boards were added to the aviary to spread around the food reward. It took a day or two for the birds to realise they didn’t have to go to one spot for food. Once these considerations were taken into account the choughs’ response time between whistle and reward improved dramatically.

Sorel and release aviary from the air 26-5-2013. Photo by Tony PaintinThere was another dip later in the month when two of the seven choughs had to be separated from the group. These two will not be released as they don’t have radio transmitters. Through positive reinforcement training and a lot of sheer luck the two choughs were shuffled across into section 1A. This is where the first target board was set up and the group have formed a strong association with it. The first few days of training after the separation saw the group of five fly down to the shelves outside and peer in at the target board bewildered by the mesh blocking them. They gradually learnt that they could use other target boards and training is back on track.

As well as flying on command the birds have been undergoing training to jump onto scales and weigh themselves. Their first response to the weighing scale being introduced was to fly to the shelving and peer down in judgement. Soon their desire for food overcame their conflict with change and they jumped on the scales. It takes patience and a basic grasp of maths for the keeper to obtain individual weights when five will jump on at once. However, this was achieved and we learnt that the choughs have maintained healthy weights.

Radio-tracking update

Radio transmitter recovered from floor of aviary. Photo by Liz CorryAround the middle of May keepers found a couple of feathers on the floor of the aviary. This isn’t particularly unusual in a group of that size. However, as the days went on and more were found, alarm bells started ringing. Checking in with the juveniles at Durrell a similar case was being seen and the alarm bells grew louder. It was suspected that the juveniles were going through a moult. Shedding feathers results in shedding radio transmitters and on the 26thMay this was nicely demonstrated by ‘Red’ losing her transmitter. Both birds carrying dummy tags have also dropped them. The first was likely due to over preening of the tail feathers the second which happened more recently was through a natural moult.

Normally choughs will not moult until their breeding season is finished. The earliest we have recorded moult for juveniles at Durrell was July. There are a few possible reasons for an early moult, such as abnormal weather patterns, transmitter attachment causing excess preening, and nutritional factors. Either way the team now needs to consider what this means for the timing of the release. Moulting can be a relatively stressful time for a bird and their welfare is top priority. A delay in release is inevitable, but the question being addressed now is ‘for how long?’

Choughs at Durrell

Captive breeding behind the scenes

Nest camera monitor showing parent feeding chough chicks. Photo by Liz CorryAfter an agonizing wait, for both parents (Tristan & Issy) and keepers, the first chough eggs hatched around the 16th May. Two chicks could be seen on the nest camera monitor begging strongly and the parents were feeding well. The next day a third chick was seen, then a fourth the following day. Extra insect feeds were taken to the aviary from around 7am until 7pm each day. Feeds consisted of mealworms, small crickets, and ants/ant larvae.

On the 19th there was some concern as only two chicks could be seen actively being next to an unhatched egg were. The quality of the camera image at that time was not very clear so the nest was left undisturbed.

However, on the 21st keepers noticed flies hanging around the nest. Concern rose and a decision was made to check the nest. Unfortunately one decomposed chick and an egg were found in the nest. Two other bodies were found on the floor of the aviary. The fourth chick was not recovered. Post mortem analysis by Durrell’s vets showed evidence of a respiratory infection. Further analysis is underway to identify the exact infection. This of course if a huge disappointment for staff considering the efforts undertaken by everyone to achieve success this year. There is a slight chance that Tristan and Issy might lay again, but it would be very late in their season if they did.

Arthur and Gwinny’s nest was checked at the same time and found to be empty. It appears that they have done nothing except build the nest this year.

Update on George

Vets perform surgery to heal George’s bumblefoot infection. Photo by Liz CorryGeorge continues to be held in the Durrell Veterinary Centre whilst his health issues are being treated. The quarantine period finished on the 22nd so in theory he can now be moved into Durrell’s collection at any time.

It was noted that when George finished his course of painkillers he began to hold up his foot again and looked in discomfort. He was immediately put back on medication and re-examined under anaesthetic by the vets.

There were a couple of pecking sores on his left foot and new cracks in the skin. The vets think the fractured middle digit might fall off naturally through necrosis and would prefer this than invasive surgery.

The main focus of this examination was to treat the bumblefoot on the right foot. The vet removed the scab, drained the infection site, cut away excess tissue, and sutured the skin tighter together. This had the effect of reducing the foot pad to a more normal size. With the aid of a pressure bandage it was hoped that George would begin to use his foot normally again and gradually correct his posture. However, upon waking up from the anaesthetic George showed an intense dislike to the bandage and made every effort to remove it. After five days of mental anguish George had the bandage removed. The wound was still healing but as it wasn’t presenting any problems, the bandage was left off and antibiotic ointment applied.

About ten days later George had pulled out his claw on the injured digit of the left foot. There was not much that could be done for this except make sure any bleeding had stopped and clean the wound. A week after that he tore the skin on the end of this digit. The vet sutured the wound with two stitches and George was put back on a six day course of antibiotics and painkiller. However, for all our concerns, George is a born fighter and was moved into the display aviary at the start of June to continue his recovery.

Chough report: April 2013

Report by Liz Corry

Choughs at Sorel

Catch-up cage. Photo by Liz CorryAt the start of April the juveniles at Durrell nominated for release were transported to Sorel. Catching them up out of the main display aviary proved a little trickier than first thought!

Having witnessed the breeding pairs being trapped and having vague flashbacks to the year before (if birds indeed do that) the juveniles were apprehensive to say the least. Keeper sat with baited trap and baited breath waiting to catch up four out of the seven birds in the aviary. Day 1 was fruitless. Day 2 saw B6974 and B6978 caught up (technically B6973 was also in the shut-off but evaded capture). Finally – Day 7, albeit with a two day break, saw the last two captured; B6973 and B6977.

Leg ring attachment. Photo by Liz CorryAll four juveniles had to undergo visual health checks by the vets before moving to Sorel. Three had already been fitted with radio transmitters so this was an opportunity to check attachment and the birds’ feather condition. B6977 was fitted with a radio transmitter and all four had Channel Islands metal rings attached to their right legs. Two of the birds had their existing plastic rings swapped for a different colour to avoid duplication with choughs already at Sorel.

Leg ring attachment. Photo by Liz CorryDuring the catch-up process it was noticed that B6975 had lost her dummy radio transmitter. From previous observations we think the transmitter had fallen off in the past couple of weeks. On examining the bird there was a new feather growing where the transmitter would have been glued on. The adjacent feather, which would have been tied to the antennae, showed signs that the tag, once unstuck, moved down the feather shaft and fell off. This transmitter had been attached for over five months, so it is not a grave concern, but is of interest. The birds with the real transmitters attached will naturally moult within this time period anyway.

When the Durrell birds were moved into Sorel there was a lot of interest from the other, Paradise Park, birds. No aggression was observed just lots of vocalising. This was a positive sign that the two groups would get on once mixed. After a few days living next to each other and adjusting, the hatches between 1A & 1B were opened to allow the groups to mix.

Soaking up the sun to improve feather condition. Photo by Liz CorryThe Durrell birds seemed more interested in their new surroundings than in interacting with the Paradise Park birds. The Durrell male (green) was seen to order around a few individuals at the start, but no one was chased or blocked from getting to food. This may have had a lot to do with them being juveniles and not breeding pairs.

However, we did notice male and female ‘pairings’ even at Flying in the poly-tunnel. Photo by Liz Corrythis early age. Black and Orange from Paradise Park hang out together and Green and Mauve from Durrell do likewise. We have also seen them pick up and carry around twig-like vegetation. One bird has gone a step further and carried material up to the top of a shelter box. A fruitless task since the wind clears anything within seconds, but at least it keeps them occupied!

Durrell vets have visited the aviary on a couple of occasions this month. On the 10th the Paradise Park group had to be caught up to be given Ivermectin injections. They also had blood samples taken whilst in the hand. All juveniles had put on approximately 20g in weight since arriving in Jersey. Weight gain was expected but needs to be monitored if the training is to be successful.

George under anaesthetic in the operating theatre . Photo by Liz CorryGeorge, the tame adult, had not put on any weight and started to become more of a concern towards the end of the month. He was spending more time lying down even when the keeper was present. It was difficult to know whether he was depressed from being alone (he still hadn’t ventured into the polytunnel with the others) or through a physical illness. When the hatches between 1A and 1B were opened he became a little perkier since he could mix with the Durrell juveniles next door to him. However, as the juveniles became braver and spent more time in the tunnel George was back to being alone again except at feed times or when sheltering from bad weather.

George’s mobility looked to be declining and he was immediately put on a course of an anti-inflammatory drug given to him in his insect feeds. This made a brief improvement until the course finished. On two occasions after that he grazed his toe on the left foot. Fear of infection and further decline in condition meant that George had to be moved back to Durrell to be housed in the Veterinary Centre.

Under anaesthetic, several X-rays were taken and George’s feet were examined. He came to Jersey with bumblefoot on his right foot. This is a bacterial infection and inflammatory reaction affecting feet. George’s rotated left leg means that he will load more on his right and has probably aggravated if not caused this issue. A swab was taken from the site of the bumblefoot. In house Lab analysis identified the bacteria present and George was put on a course of antibiotics as well as the anti-inflammatory medication. Bio-security legislation requires George to undergo a quarantine period whilst with the vets before he can be moved into one of Durrell’s aviaries. He gets a lot more attention in the Vet Centre than at Sorel so his mood quickly improved although his physical condition is still a struggle. We will review his situation once the antibiotics have finished.

Pre-release training

Target boards on food stands. Photo by Liz CorryThe choughs are being trained to fly in and out of the release hatches (within the aviary)on a whistle command and rewarded with food. This is to ensure that during the early stages of the soft-release the birds will come back to the aviary and that they can be safely locked in overnight. They will learn that the aviary is a safe shelter and holds food resources if they struggle to locate any in their first few months exploring the coast. In the long term this should also help with monitoring their condition after release.

Target boards on food stands. Photo by Liz CorryTo achieve this, the aviary has been designed to let keepers train the choughs to go through an internal set of hatches before attempting the external release hatch. There are large target boards on the food stands and two tables in the polytunnel (kindly donated by Tony Pirozzolo at Café Firefly). Hopefully the birds will start to associate these boards with food and will easily spot them when flying around after their release.

The birds responded well when they had access to the first half of the polytunnel. Whilst still nervous of the keepers they would fly in for food once the keeper had blown the whistle and left. When they were given access to the entire polytunnel they started to become less responsive.

Radio-tracking and behavioural studies

Jess, chough field assistant, successfully locating Catherine the ‘chough’. Photo by Liz CorryThere have been several practice sessions this month on how to radio-track choughs. More importantly, learning how the Jersey landscape affects radio frequencies and discovering the practicalities involved. Initially this involved checking that the transmitters on the birds were working and seeing how far the signal will travel. When feeling a bit more adventurous this progressed to seeing if keepers could track down a live moving target. Durrell staff, with transmitter in hand, kindly volunteered to be ‘choughs’ and hide somewhere between Sorel point and Devil’s Hole. They took the role to heart by belly-crawling through gorse bushes and sitting on cliff tops. Despite all their efforts to deceive the radio-trackers they were all found and pretty quickly. Next test….paragliding volunteers!

Jess undertaking behavioural observations at the release aviary. Photo by Liz CorryJess Maxwell, a Durrell intern student, is assisting with the field project and undertaking a behavioural study for her degree. Her observations started this month and will continue post-release. These studies involve Jess sitting in a field for two hours each day which is why Jess is very grateful for the recent weather improvements. She is studying the group dynamics to see if they behave the same pre- and post-release and try to assess what is the ideal cohort size for release. Hopefully this work will be replicated with future releases and the data can be used to evaluate the ongoing project.

Choughs at Durrell

With the last of the release birds being moved out of the display aviary we are now left with three birds in there including Gianna. These choughs have been joined by a pair of breeding toads who have decided to spawn in the choughs’ ‘pond’! Keepers have provided the choughs with water bowls to deter them from going near the pond. At the time of writing we now have tadpoles.

Nest camera still images from Tristan and Issy’s nest showing her complete clutch as of 26th April. Photo by Liz CorryOur two breeding pairs of choughs have been very busy off show. Keepers provided nesting material in the appropriate stages; large twigs, heather thatch and finer twigs, wool and horse hair. Both pairs set to work building nests and completed them relatively quickly. Keepers never witnessed any copulation, but on the morning of the 22nd they did see their first egg. Unfortunately this was when Issy got off her nest, walked along the shelf and laid the Issy patiently incubating her eggs. Photo by Liz Corryegg there much to the dismay and confusion of the keeper watching. On inspection of the nest camera it looked like there was an egg in the nest too (although the wool can be deceptive) so the shelf egg could be the second egg not the first. On the 25th, keepers thought they could see three eggs in the nest and by the 26th Issy was sitting tightly on them. If all goes to plan these eggs should hatch towards the end of May.

Keepers are not sure if Arthur and Gwinny are up to anything. We do know that they have a nest. Somehow the camera lens moved position so we do not have a clear view of the nest but from their behaviour it doesn’t appear that Gwinny is sitting on eggs. We don’t want to disturb them so will continue as normal and monitor them as closely as we can.

Keepers have also been kept busy at the display aviary after members of the public reported seeing the choughs “trying to escape”. Being inquisitive birds they investigate everything including broken threads in aviary netting. It wasn’t an escape attempt more a quality assurance test. The height of the aviary makes it very difficult to repair holes in the netting with just a ladder and a good head for heights. Jono le Maistre, tree surgeon, kindly offered his assistance and with harnesses firmly attached climbed the poles to fix the netting.

Chough report: March 2013

Report by Liz Corry

Captive choughs at Durrell

Chough in a blizzard. Photo by Liz CorryThe breeding pairs were caught up out of the display aviary at the start of the month and moved down to their breeding aviaries. It took three days to get them all. By the second day they were all wary of the catch-up cage and it took Tristan three days before he summoned up the courage and/or his hunger got the better of him.

Nesting material was added to the breeding aviaries almost straight away, but the record-breaking snow blizzard deterred the birds from doing anything. As soon as this past and the weather ‘improved’ they began taking the material into the boxes.

The choughs in the display aviary braved the elements at the start of the blizzard. By the end of the first day the snow had settled on the netting and transformed the aviary into an igloo. They were probably warmer than their keepers.

Thanks to the generosity of Paradise Park we have been given two brand new Sony 700 line nest cameras. With weather disrupting breeding behaviour we took the opportunity to install one of the new cameras. The existing camera in SF3, whilst showing a clear picture, was not suitable in design, size, and position and was removed.

Gianna looks out into the snow. Photo by Liz CorryGianna has started to be a bit more forthcoming towards keepers now she has settled in to the main display aviary. She has started conditional behaviour training and is learning to fly on command. Once this is mastered she will begin learning to weigh herself on scales and enter/exit carrying crates without being handled. Hopefully the other choughs in the aviary will follow suit in the near future

Arrival of Paradise Park’s 2012 juveniles

Three juvenile choughs, hatched in 2012, and the trained adult male, George, were scheduled to arrive by plane in Jersey on the 12th March. Lee Durrell had kindly loaned her Navajo plane for the collection of the choughs from Paradise Park. Colin Stevenson was going to be the pilot.

However, with the unprecedented snow blizzards this plan was thrown into mild chaos. By hook or by crook the birds had to arrive by the end of that week. If not, the next import date would be in mid-April. Having been ‘snowed in’ for two days at the Wildlife Park, keepers were far from optimistic that the birds would arrive.

A decision was needed by the 13th in order for the airport authorities to sign off on the paperwork for a flight on the 14th. Despite the 9ft snow drifts that lined the roads the route to the Sorel aviary was still accessible. The next task was making sure that Lee’s plane could get onto the runway on the 14th, let alone be able to fly. Colin, the pilot, reported that:

Preparing for take-off. Photo by Colin Stevenson“Steve Driscoll, the Ports of Jersey Group Operations Director and André Rabet, the Airport Engineering Director made a significant intervention by diverting their very stretched crews to clear our taxiway.

The Airport snow clearing team themselves, once detached from their normal duties, cheerfully made short work of clearing the snow from our taxiway and had us operational by Wednesday night…..Eric, the digger driver, worked at the hangar for four and a half hours, until half past seven in the evening – after starting to clear snow at the airport at 5am that morning.”

After, what we were told were near perfect flying conditions, Colin, co-pilot Gregory Guida and the choughs touched down in the early afternoon. The choughs were accompanied by David Woolcock, Curator at Paradise Park, who had kindly volunteered his time to stay at Durrell for two days to help settle the birds in and discuss training protocols.

Choughs receive veterinary inspection. Photo by Liz CorryOnce the birds arrived at Durrell they were swiftly whisked away to the Vet Centre under quarantine conditions. There the birds had a general health check, blood samples taken, ID rings attached, and radio transmitters attached where appropriate.

On inspection of two of the juveniles it was noted that some of their tail feathers had ‘fret lines’. The central tail feather, Choughs receive veterinary inspection. Photo by Liz Corrywhere the radio transmitter is attached, had broken off quite close to the base. It meant it was not possible to attach radio transmitters to these two birds. After careful consideration of the options it was decided that these two would not be used in the trial release. Their feathers will be allowed to moult through naturally at the end of the breeding season and we would consider them for a second release if planned.

Damaged tail feather. Photo by Liz CorryThe two birds involved were still given Jersey addressed metal ID rings in case they accidentally escape over the next few months. It will not make them easier to find but if recovered it will make it easier to identify where they came from. The only one who has not been given a Jersey ring is George due to his leg deformity. All the choughs at Durrell and now at Sorel have transponders implanted under their skin as another means of identification if recovered. These tiny ‘microchips’ were fitted by Paradise Park staff prior to the birds departure for Jersey.

After what must have seemed like a lifetime for the birds they finally got to leave the Durrell Vet Centre and be transported by car to the release aviary at Sorel. Andrew Terry volunteered his time and more importantly his 4WD to transport the birds. Unfortunately the last 100m of track leading up to the field site had not been cleared and the driver faced a 6ft wall of snow. The last leg of the journey had to be done on foot from Sorel car park, but finally with the sun setting the choughs made it to the aviary. They were released into the back half of the enclosure (Sorel1A) where they will stay until the Durrell group get moved up and then mixed together. For the next thirty days quarantine restrictions will apply and only designated staff can access the aviary.

Choughs at Sorel

Chough aviary at dawn. Photo by Liz CorryThe first quarantine faecal sample was submitted to the lab on the 18th. For the choughs (and their keepers) to be ‘released’ from their quarantine period a minimum of three pooled faecal samples need to be taken on a weekly basis. Analysis of these samples will determine whether more are needed and/or if treatment is required.

The first faecal sample showed positive for nematodes and Chough in Sorel aviary. Photo by Liz Corrycoccidians, albeit at low levels. It was decided to not move the Durrell choughs until a second faecal sample could be analysed and a decision made about treatment. The second faecal showed low levels of coccidians and nematodes, but since this would be typical for wild birds as well it was not deemed significant. However, as a standard of good practice we will treat George’s group with a single injection of Ivermectin (anti-parasitic drug) prior to release.

A Bushnell trail camera was installed in the aviary when the choughs moved in. This will act as a security camera as well as documenting the birds’ behaviour when keepers are not present. It has proven very useful so far and we have been able to see how the birds react when dogs, people, and heavy machinery are around. It has shown that like most other corvids, choughs can be active from 05.00 onwards.

The camera has also recorded a surprising, and unprovoked, attack on George by the other male in the group. This might be expected since George has been kept separate from the group over the last 5-6 weeks. From the keeper’s point of view, whenever they enter the aviary, the juveniles hide or are too busy eating to show any animosity towards George. Most squabbles seem to be between the juvenile male and the female without the radio transmitter so it was interesting to be able to remotely observe this behaviour.

Pre-release training

George, having been trained prior to arriving in Jersey, will be the role model for the other choughs when they start their conditional behaviour training. However, it is not a role he can easily jump into. First he needs to adjust to his new surroundings, the new weather conditions (gale force winds are not a common occurrence in Hayle) and, even more challenging, adjust to his new keepers.

Whilst George settled in very quickly (eating straight away) it took him a few days to be confident enough to perch close to the keepers. He will now fly to the keeper when called and can jump onto the scales to be weighed. This last task is quite a challenge in his new surroundings. For a start, on certain days he has to battle against the wind. The scales are a slightly different design to what he is used to which will make him insecure. We have ordered the same scales as Paradise Park, but they have to be delivered from the manufacturer in Germany.

For the keeper to reach the shelving and be at a comfortable height with George a ladder is required. At first George was scared of the long ladder, so they were swapped for a small pair of steps. Gradually he warmed to the ladder, mainly due to the keeper using it a lot to carry out DIY work inside the aviary.

George hoping for a treat. Photo by Liz CorryThe biggest challenge was in keeper and bird trying to understand each other. George knows the command for “please jump on the scale” and he knows that he will be rewarded with insects. The keeper knows the correct command and the correct reward. But when the bird doesn’t want to jump up in the wind onto a strange object it is very hard for it to convey this. It is a lot easier to hop along to the keeper, look doe-eyed (trust me they can do this) and ‘guilt’ the keeper into giving them insects!