Chough report: February 2019

White died this month due to health complications. Photo by Liz Corry.

By Liz Corry

Where to begin? The start seems a good place, but this start begins with an end. Two in fact, maybe three. Following? You will.

Wild breeding population suffers a setback

We sadly have to report the death of two choughs and a highly likely third. At the start of February, White was flying around with tatty feathers looking rough. He soon started showing symptoms of a syngamus issue despite ‘clean’ faecal samples. At the same time we noticed that Mauve, his partner, was not being recorded at the feeds. It is easy to lose an individual in a large flock, but pairs stick together.

White began to deteriorate so he was caught up and checked by the Vet. It took two days to trap him because the entire flock are now wise to our methods. Once locked in the aviary it was clear he was in trouble.

His was surprisingly good weight for a sick bird, which in itself was a concern. He has always been a larger bird, you can spot him in the flock based on size alone, but you would expect a slight weight loss.

Worming proved futile and he died a few days later. Post mortem results showed that his airways had become blocked by plaques of pus that had dislodged in the trachea. Why he had the plaques in the first place is unknown.

Whilst all this was going on Mauve was still absent. By the end of February, we had to conclude that Mauve was no longer with us.

White preening his partner Mauve in 2015 – their first season together. Photo by Liz Corry.

Mauve was one of the original group released in 2013. She had an interesting start to her free-flying life in Jersey as recounted in several of the earlier reports. White was brought to Jersey at the end of 2013 and released in 2014. They paired up in 2015 and a year later they had chicks of their own out on the north coast.

Cold case: chough PP012

On the same day that White passed, I was informed of a dead chough found in a garden at Grosnez. As Mauve had been missing I naturally assumed it was her.

On Sunday 17th, members from the Birds On The Edge team ran a stall at the annual Seedy Sunday & Wild About Jersey event (see below). Within an hour of the doors opening to the public I was approached by a lady from Grosnez. Seeing Lynne, our volunteer dressed as a chough, reminded her – she had a dead chough in her freezer!

The next 24 hours in the story were filled with twists and turns. In a nutshell, the lady had found the dead bird on her property in September 2017! At the time she wasn’t aware of the chough project, but had carefully double-bagged the body with a descriptive note attached. Nowadays she regularly sees the choughs flying over her land and knows what they are. As we all know, time ticks on and we forget things. Until you bump into a lady dressed as a giant chough!

Clearly this bird was not Mauve. The chough in question was Carmine, a wild chick hatched in 2017 belonging to Q and Flieur. She was one of the juveniles with syngamus who we had trouble trapping in the aviary. Since she was never medicated she probably succumbed to the infestation whilst flying around Grosnez with her parents.

A juvenile red-billed chough. Photo by Liz Corry.

We are very grateful to the lady for preserving Carmine and reporting it as we now have closure on a case. We can add this info to our dataset which aids future management plans.

If you do find a dead or injured chough in Jersey please call 01534 860059 or contact any of the project partners. We can come to you and collect the bird. All of our birds have metal leg rings on with a unique number. This will tell us who they are even if they have lost their plastic rings.

Replacement rings

Replacing missing rings on the choughs is turning into a never-ending challenge. Not helped by the birds either not showing at the feed or not staying inside when we try to shut the hatches.

A plastic leg ring found in grassland near the aviary. Photo by Liz Corry.

When White was trapped inside, I had the opportunity to replace Green’s missing rings. I could not fit the black gull-ring used with Green and the original release cohort. These need to be heated in hot water to open them without the material snapping; also tricky to fit one-handed. Since I was working alone without a thermos I made an on-the-spot decision. I fitted a black and white striped ring we happened to have in the ringing box.

These rings are normally used in the UK to identify a Cornish chough. As we don’t expect many of these to turn up in Jersey over the next few months I’m sure it will do as a temporary measure.

To get around the struggle of trapping the birds I tried the route of shutting the hatches after the birds had gone to roost. Fingers crossed at least one of the birds who still roost in the aviary would be a bird we needed. There were ten birds still at the aviary as the sun set. Two, maybe three, used the external roost boxes. The others went inside. The plan almost failed when the hatches didn’t close. I climbed the framework, silently cursing so as not to spook the birds, and manually closed the broken hatches.

Returning in the morning I was met with an interesting find. Earl and Xaviour had slept at the aviary. We thought they were back at Plémont having regularly been seen there before sunset. It now appears they are there for supper before flying back to Sorel to sleep. This finally meant Xaviour could have her two orange rings returned. Annoyingly she was the only bird in that group needing rings. We still have two Orange-right-only birds flying around. We need to see who if any they are partnered with to know who they are.

Potential new breeding pairs for 2019

Despite the sad loss of a breeding pair there is good news for the 2019 season. We have at least four new pairings thanks to the birds maturing. Zennor’s love for Skywalker is still going strong from the first moment she set eyes on him at Sorel last summer to a very exciting moment I can’t reveal until the March report!

Vicq, a foster-reared female has caught the eye of wild-hatched Osbourne. He isn’t even a year old yet, but it appears Vicq has staked her claim. And of course there is her clutch-mate Xaviour whose second year at Plémont may prove fruitful.

At present we have fourteen potential breeding pairs for 2019. I’m not sure how possible it will be for me to monitor them all throughout the season. I’m really hoping not to repeat the fiasco of last year when we miss-timed the hatch dates and were too late to ring the chicks. I may well be looking for volunteers.

Population census

The 2019 attendance record at the supplemental feeds has been relatively poor; around 60%. There are a few consistent absentees such as Earl and Xaviour who are spending more time back at Plémont. Other absentees have not been as easy to determine. The death of White obviously made us uneasy. What if we have lost more?

The dolmen at Grantez is one area choughs have been spotted this month. Photo by Liz Corry.

When possible, I have travelled around to known foraging sites to try and count the choughs. Of course to count them, I need to see them and I appear to be having issues with that. First off, Jersey’s potato fields are currently covered in plastic sheeting. In a way searching is easier because there are swathes of land where the choughs won’t be going. However, it also makes it hard to see anything when the morning sun reflects off the plastic.

Potato fields at L’Étacq covered to protect and encourage new growth. Photo by Liz Corry.

More fields near Grantez giving the illusion of water bodies when viewed from afar. Photo by Liz Corry.

I had a report sent in from one of the States’ rangers of two choughs in a field at Grantez one morning. Grantez is a perfect stop off for choughs with grazing sheep, a high vantage point to look over St Ouen’s Bay, two large fields grazed by donkeys, and a dolmen. Choughs love a bit of neolithic architecture. Of course, when I go up they aren’t there.

The same can be said for Le Pulec, Les Landes, and Plémont. All places I have had confirmed sightings this month. Fortunately we have a report of 13 at Les Landes at the same time we had 28 at Sorel. So at least we know we still have at least 41 choughs.

Not a chough – but perfect chough foraging habitat. Photo by Liz Corry.

Wild About Jersey

This year’s Wild About Jersey teamed up with Seedy Sunday a free seed exchange event. Le Rocquier School hosted the weekend with the Saturday (16th) dedicated to volunteer survey training for butterflies, bats, reptiles and the new Pond Watch scheme (takes over from Toad Watch). Sunday (17th) was the Seedy Sunday open day with various stalls, talks, interactive exhibits, and a guest speaker Alan Gardner, The Autistic Gardener.

Birds On The Edge had a stall staffed by Cris Sellares, Tim Liddiard, and myself. Conservation crops, a chough nest, and a dung beetle (soft toy) were laid out so the public could learn more about our work. I gave a talk entitled ‘Witches and Unicorns: how saving one species helps another‘. Trust me there is a link!

Drumming up support for Birds On The Edge. Photo by Liz Corry.

Not only did the event raise the profile of Birds On The Edge and bring to light the fate of Carmine, it managed to raise £1248.62 for Jersey Trees for Life. The money will be used to maintain and create more red squirrel bridges, across our Jersey’s roads.

Small mammal, big pain

Mice attempted to break into the chough feed-twice! Photo by Liz Corry.

The much ‘loved’ rodents struck again at the aviary. Droppings covered almost every surface in the keeper porch. Anything with the slight whiff of food about it had been nibbled including the first aid box! And then of course there was the ‘heavy duty’ storage box for the chough food.

Mice are smart. As evidenced by the fact the only place they chewed the box was the hinge – the weakest point. They didn’t succeed in reaching the pellet, but they did contaminate it with plastic shavings which meant it couldn’t be fed to the birds. As a temporary measure, I taped the hinge whilst I went to the local hardware store. It bought some time at least.

Plasterers metalwork is being use to add extra rodent-proofing to the aviary doors. Photo by Liz Corry.

With my zoo keeper thinking hat on I wandered around the store looking for an easy, cheap, will-fit-inside-my-Hyundai, solution.

Plasterers beading! At just over £2 a strip it made for a cheap and easy to fit edging strip to the door frame to stop mice and shrews from getting in. The metal work is flexible enough for a human to bend it by hand but sturdy enough to deter a mouse.

I also salvaged some builders metal work from the skip. Durrell’s HQ is currently undergoing repairs and the builders had just that week ditched some scraps. All I need now is for them to ditch their cutting tools as my Leatherman doesn’t fair well with the more robust stuff.

A metal bin has been donated to the project to stop the mice eating our supplies. Photo by Liz Corry.

 

Thanks to a charitable donation we were given a metal storage box for the chough food. The mice and shrews can only get into this if they work together to form ladder and flip the lid.

I wouldn’t put it past them. Just take a look at the camera trap image below from inside the aviary.

Spot the Mission Impossible mouse trying to reach the chough food. Photo taken using Moultrie camera trap.

Magpie-proof feeders mark II

A new design of chough-feeder. Photo by Liz Corry.

We now have another design of chough feeder in use at the aviary. The choughs successfully probe for food reaching every nook and cranny. Magpies are limited by their bill shape and length.

It doesn’t stay that clean for long and has room for improvement in terms of ease of cleaning. We also have to remember to screw the lid back properly.

I was lazy one evening, and screwed it back by hand. The next day I returned to find the choughs had freed the bracket and opened the lid!

Clearly their idea of slow-release feeding is not the same as mine.

 

Chough report: June 2018

By Liz Corry

Breeding success

The choughs have been busy ‘behind the scenes’ resulting in a record-breaking breeding season. By the end of June, we had found four active nests with a total of ten chicks. We knew four chicks had hatched at the end of May. We didn’t have to wait long before Ronez Quarry sent photos of a second nest with chicks.

Dusty and Chickay’s nest with three chicks safely tucked away in a quarry building. Photo taken under license by Toby Cabaret.

This nest belonged to Dusty and his partner Chickay: an astonishing and heart-warming sight. This was their third season nesting, finally they had chicks, and from the looks of things they were at least three weeks old.

The icing on the cake is the uniqueness of the coupling. Chickay was hand-reared, proving that our choice of methods worked, and Dusty is himself a wild-hatched chick.

Ronez hired equipment to access the chough nests under license. Photo by Liz Corry.

A site-visit was arranged for 16th June when the quarry was not in operation. Ronez hired a cherry picker to access the nests. What we found was a mixed bag of good news and bad news. Some nests had failed, some succeeded beyond expectations. And then one complete surprise; a nest we had no idea about.

This nest contained one chick approximately four weeks old. We also noticed twigs in a nest-box we had put up in 2014. This is the first time the birds have tried to use this box. Either they decided it wasn’t a suitable place to continue or the pairing just didn’t work out.

The table below aims to answer any queries the dedicated reader has about which pairs succeeded.

Pair Bred before? Nest status
Green & Black Yes empty
Dingle & Red Yes empty
Kevin & Bean Yes 3 chicks
Dusty & Chickay No 3 chicks
Q & Flieur Yes empty
Lee & Caûvette Yes 2 chicks
White & Mauve Yes empty
Trevor & Noirmont No no nest found
Pyrrho & Percy No empty
? & ? 1 chick
Total 9 chicks

 

However it also throws up a few queries, like “didn’t Kevin and Bean have four chicks in May”? Yes they did. Sadly one is no more, probably the runt of the clutch, but to have three chicks still alive and well is a first for Jersey’s choughs.

The nest belonging to Lee and Caûvette was found to contain two chicks. Photo by Liz Corry.

You might also be tempted to ask “does the mystery chick not belong to Trevor and Noir“? That, dear reader, is something I still don’t have the answer to a month after the site visit. And one that is driving me insane so lets return to June 16th; life was simpler then.

We had taken a licensed ringer into the quarry with us so we could ring the chicks and get DNA samples for sexing. This is supposed to be done when the chick is around three weeks of age. Clearly from what we were seeing these chicks were older. We did not want to risk disturbing them for fear they prematurely left the nest once we put them back. It is a long way to fall!

That is ok, we thought, we can just ring them once they reach the aviary. We can see which adults feed them and work out ownership that way.

How naive we were.

Fledged chough chicks reach the aviary

Below is a montage of footage taken during the supplemental feed once the chicks had fledged. Imagine having a baby that can fly and walk and scream for food whilst doing said actions. Then multiply by two or three. That is what it’s like for a chough parent for the first few months. Note how loud the begging starts off then trails away. Always lingering, never stopping.

From appearances, Chickay was not keen on parenthood. She left most of the feeding duties to Dusty. One of our daily reports records an observation of Kevin “karate kicking” a chick in response to the constant in-your-face begging. Quite often at the feeds you would see chicks accidentally push the parent off the food-stand or shelf in the frenzy to beat its sibling to the food on offer. You also saw them beg at non-breeding individuals who looked more than a little perplexed by the situation.

Throughout all this, the three newbies (Han SoloChewy, and Skywalker) remained locked in quarantine in one half of the aviary. We could not attempt to catch-up and ring the wild chicks until the three had been released. That was scheduled for July.

All we could do in the meantime was try and figure out how many chicks each set of parents had. Lee and Caûvette made things easy as they continued to visit Les Landes and Grosnez, taking their chicks away from the mayhem for a few hours each day. We knew both of their chicks seen on the 16th had survived and arrived at the aviary the last week of June.

Family portrait: Lee and Caûvette with their two chicks at Grosnez. Photo by Mick Dryden.

Lee with his two noisy chicks. Photo by Mick Dryden.

Dusty and Chickay were tending to three chicks (well Dusty was at least). They would take them back and forth between Sorel and the south-east corner of the quarry. Initially there was concern over one of the three chicks as it looked relatively lethargic. We put this down to the heat and that it could be the youngest, struggling to keep up. Dusty was always very sensible, taking his chicks into the shade to rest.

Dusty and Chickay keeping their chicks in the shaded parts of the quarry. Note the chick lying down next to dad whilst the other two preen next to mum. Photo by Liz Corry.

Kevin and Bean‘s three also made it from nest site to Sorel. However, they made it a little harder. Most of the time their chicks were kept around Sorel Point. Often out of sight, but not earshot. 

View across the quarry from Sorel Point. Photo by Liz Corry.

Then the mystery deepened. Q and Flieur turned up to the supplemental feed with two chicks. “But their nest was empty?” you cry. Yes, yes it was. “And the surprise nest only had one chick in it?” you answer back. Yes, yes it did.

The Plémont pair

Earl and foster-reared Xaviour, or the Plémont pair as we call them, are still roosting out at Petit Plémont. Their amazing choice of nest site has made it impossible to tell exactly what they have been up to this breeding season. We did suspect, from the couple’s behaviour out of the nest, that the female was incubating eggs.

Earl taking a break on the WW2 bunker ruins at Petit Plémont. Photo by Liz Corry.

One was seen carrying something white away from the nest. An optimistic observer thought it was a faecal sac. These ‘sacs’ are produced by chicks and carried away from the nest by the parents. He changed his mind when he saw the adult pecking away at it. The white object started to look more like an egg, but smaller than a chough egg. Out of reach of the observer, we will never know the true-identity of the object.

In the days the followed, hope of a successful nesting attempt began to fade. Xaviour was spending more time away from the nest. Foraging around the headland and neighbouring cliff tops to feed herself rather than take back to an expectant nest.

The pair are young. This year should be taken as a positive step forward in their development. They remain the first pair to set up a territory away from the release site. As they mature they will no doubt see success with their nest.

Star Wars saga continues

Han Solo, Chewy, and Skywalker continue to adjust to life at Sorel whilst in quarantine. Faecal samples from the two Paradise Park birds tested positive for nematodes.

Staff began to hear sneezing from the confined group a week or so after their arrival. Nothing to cause alarm, but enough to warrant a wormer pre-release.

This was scheduled for 20th June. On the 17th the Bird Department received a call to say that there were only two choughs locked in the aviary. Skywalker was missing. Scanning the aviary, it became apparent that he had not used Jedi mind tricks to escape. He had in fact managed to squeeze out through a hole in the netting, no doubt created by rodents.

He was not with the free-living choughs at Sorel. Well not in plain sight at least. The following day he couldn’t be any more obvious if he tried. Skywalker was on the roof of the aviary alongside Zennor a young female.

Since the boys arrived at Sorel, Zennor has shown a keen interest in them. She sits, on the opposite side of the netting during every feed whilst everyone else is tucking into their meal. We thought her interest was in Han Solo as they had touched bills through the netting; fiction becoming reality? Alas, it was Skywalker she wanted which worked to everyone’s advantage as he had another chough to follow, returned to the aviary, and we managed to get him safely back inside.

Return of the Jedi: Skywalker shortly after being trapped back inside the aviary. Photo by Paul Pestana.

All in time for the vet to visit on the 20th, give all three a wormer, and fit Han Solo with a transponder chip just like all the other captive-bred birds have. Bird Department staff also kitted them out with shiny new leg ring combos to make it easy to tell them apart once released.

Luckily the States Vet agreed that no extra time needed to be added to their quarantine period. Once complete, at the end of June, they can be released.

May the force be with them.

Aviary maintenance

Despite the recent rodent-proofing at the release aviary there are still weak points in the defences. As exemplified by Skywalker’s escape. Without a major overhaul of the aviary design there is not much to be done.

Mind you, that overhaul may come sooner than imagined. The shelving has now warped so badly that bolts keeping the hatches closed no longer reach. The hinges on the external keeper door snapped right off due to rust.

This is the first year the pre-release group have not had full access to the flight tunnel in a bid to avoid further premature releases. Once the new boys have been released and settled into life at Sorel we can start repair work.

Supplemental feeds

The choughs have seen a few changes to the menu this month due to food shortages. There is still no Remilline pellet in stock in Jersey, so the egg-based diet returned to the menu. The live-food manufacturer has been experiencing issues with their mealworm stock resulting in fewer or no insects being delivered. Not the best of timing. We had to increase the amount of supplemental food this month in response to an increasing demand. Obviously with mouths to feed, the breeding pairs become more dependent on the aviary feed.

Lights, camera, action

Ronez Quarry very kindly funded young film maker Sam Hertzog to fly to Jersey and produce a short film about the chough reintroduction project. Sam had four days to try and sum up the last five years into a seven minute documentary. To make the challenge that little bit harder we threw in rolling sea fog, a field manager dying of hay fever, and birds that never paid attention to the script.

Sam succeeded. You can view his film below. We are very grateful to his friend Elin Cunningham for proposing the idea and for being the boom operator, gaffer, assistant director, chauffeur….