Chough report: August 2021

Just in case their calls were not loud enough. Photo by Liz Corry.

By Liz Corry

Breeding season roundup

Don’t let the sound of a begging youngster fool you. The 2021 chicks are now fully independent. They just like to try their hand (or wing) once in a while with their parents.

Four youngsters have survived. This is a disappointing number although four is better than none. Thankfully, each from a different family which helps a little to spread the genetics around. Speaking of which, their DNA sexing results came in at the start of August. We have one male and three females. They all have names now too:

Rocky, breaking gender conformity with his bright pink leg ring, is the offspring of Dusty and Chickay.

Rémi, as reported last month, is wild-hatched Minty and Rey‘s first chick. She might be a St Ouen parishioner, but certainly isn’t seen as an outsider by the St John residents. 

Wally Jnr. shares a lot of characteristics with her mother Wally when she was a fledgling at the aviary. There may have been a Kevin Jnr. but we never managed to sample the second chick before it perished.

Monvie is Bo and Flieur‘s girl who sports a mauve over yellow ring. Her name is taken from the Jèrriais greeting Man vyi meaning my old mate/friend (if addressing a woman it is Ma vielle). Its pronounced a little like you are saying ‘mauvey’ which helps to remember her leg ring colour. Learn more about the language at L’Office du Jèrriais.

Sadly, but not surprisingly, the body of the missing fifth chick was found by Ronez Quarry staff on the 16th. We ringed it on 30th June so we knew it was Dusty’s and now know it was male. Judging from the state of the body he had died when we first reported it absent from the feed.

Two breeding pairs at Sorel resting in the rocky shade. Photo by Liz Corry.

Not all of the breeding pairs survived the season. We lost a male resulting in a ‘divorce’ of another pair and the re-joining of old flames. It also looks like we have lost the female who roosted and tried building a nest in Trinity. She has not been seen anywhere since early summer. 

All being well, we will have two new pairings attempt to nest in 2022 bringing it to eleven pairs. The same as in 2021 despite our losses.

West is best

View of Grosnez with the other Channel Islands on the horizon. Photo by Liz Corry.

The choughs still preferred to hang out on the north west coast in August. Who could blame them with the views.

Cliffs from Grosnez to Plémont are frequently visited by choughs. Photo by Liz Corry.

Not to mention the ‘playground’ that is Les Landes with the racecourse, stables, paddocks, rooftops, and scattered WW2 German-made structures.

As long as they keep out of the way of the occasional model aircraft and, more permanent, resident peregrines!

This peregrine at Grosnez might be more familiar with choughs than I would like. Photo by Liz Corry.

Food for thought

From March to July this year we had a student placement working on the project. Riccardo rose to the challenge of re-establishing our breeding colony of mealworms for the supplemental feed.

We have never really had enough continuity and/or success to fully rely on in-house production. We buy in 1.5kg-2kg of mealworms per week from the UK to supplement the choughs’ diet. We get a discount since it comes with the bulk order for Jersey Zoo’s residents. Yet this still equates to hundreds of pounds a year.

Thanks to Riccardo’s efforts we might be making a breakthrough. After a month of breeding we have produced about 500g of mealworms. Not enough to cancel the UK order, but it should keep our costs down.

There is potential to expand the operation…providing a certain DIY store continues to stock our ‘high-tech’ housing facility aka drawers.

Mealworm breeding setup for the supplemental feed. Photo by Liz Corry.

It’s a delicate balance of temperature, humidity, and the right amount of nutrients appropriate for each of the four life stages. Fingers crossed; we can continue Riccardo’s good work now he has returned home to Italy.

Next time you see an advert for ITV’s I’m a Celebrity….just think about the effort and expense that goes into raising mealworms. And then the waste!

Chough report: July 2018

A two-month old chough chick exploring Grosnez headland. Photo by Mick Dryden.

By Liz Corry

Jersey now has 46 choughs flying free thanks to a brilliant breeding season and release efforts by Jersey Zoo staff. Details of how that came to be this month are explained below.

Who’s the daddy?

Determined to crack the mystery over the wild chick lineage, we began catching birds to fit leg rings. It took a couple of weeks and help from Ian Buxton and Cristina Sellarés  (licensed bird ringers). By the end of July we had nine chicks fitted with leg rings and no birds left unringed. A total of nine birds.

Tarsus length being measured on a wild-hatched chick. This can be an indicator for sex. Photo by Elin Cunningham.

Plastic leg rings on a wild-hatched chough to identify individual (pink) and year of hatch (green). Photo by Elin Cunningham.

What we are not clear on, and may never know, is whether we had ten or eleven chicks at one stage. On 4th July Q and Flieur were seen feeding two unringed chicks. When we checked their nest on 16th June it was empty. Judging by the age of the chicks at the aviary they could not have fledged before the 16th. Did Q and Flieur nest elsewhere? Are they responsible for the mystery nest we found in the quarry?

Trevor and Noir were also seen feeding one or two unringed chicks at the start of July. Are they responsible for the mystery nest? Are these chicks in addition to Q and Flieur’s?

Noirmont feeding an unringed chick with partner Trevor looking on. Photo by Liz Corry.

We knew for certain Lee and Caûvette had two chicks and were happily taking them to Grosnez each day. Kevin and Bean had fledged three chicks. Yet, by the start of July, they were clearly only feeding two unringed chicks. Had one of the other pairs adopted the third chick over the course of the feeding frenzies at the aviary?

Lee feeding one of his two chicks at Grosnez. Photo by Mick Dryden.

By the time we had fitted all the leg rings, Trevor and Noir had stopped feeding a chick(s). Was this because they had died or because they never had them in the first place? The blood samples we send off only inform us about gender. There is a lot more involved to test for lineage.

For now, all that matters is that we have nine chicks being fed and nurtured out at Sorel. The wild chicks are named according to their leg rings until we can think of better names.

Dusty & Chickay Red White Blue
Kevin & Bean Green Orange  
Lee & Caûvette Yellow Black  
Q & Flieur Mauve Pink  

You can already see a difference in the chicks as they get older. Bill colour is changing. More importantly they are picking up crucial skills from the adults, whether parents or not. We have seen them drinking from the water tray and lifting the broken slate enrichment area in the aviary looking for insects.

A recently fledged chick chilling with the flock at Sorel back in June. Photo by Liz Corry.

Chough chicks can be very forceful with their begging. Photo by Liz Corry.

Mega-beast: Dusty feeding one of his chicks. Photo by Liz Corry.

Dusty regretting parenthood? Photo by Liz Corry.

An unringed chick begging at Yarila (non-breeding bird) eventually pushing her off the stand. Photo by Liz Corry.

Dusty feeding one of his chicks whilst Chickay (mum) goes about her business. Photo by Liz Corry.

Chickay pretending not to see or hear her chick. Photo by Liz Corry.

Star wars saga

The three males – Han Solo, Skywalker, and Chewy – held in the aviary for a month have been officially released.

Release day saw 45 choughs turn up to wish the newbies well or steal their food. 50:50 really. Photo by Liz Corry.

Skywalker’s brief adventure outside in June meant it came as no surprise to see him leave first. Albeit to the roof of the aviary where he sat preening Zennor.

Skywalker’s (on the left) first hour of freedom spent with his new love of his life, Zennor. Photo by Liz Corry.

Han Solo and Chewy were not as quick to venture outside; once they did they appeared at ease, making friends with the free-living group. Although less at ease with the wild chicks who had decided to test the newbies’ untapped parenting skills by begging in their faces.

An unringed chick following Skywalker around in the misguided hope of free food. Photo by Liz Corry.

After a few days Han stopped showing up at the feeds. Since group attendance rate was around 80-90% it was hard to know if he was in trouble or not. He made a reappearance four days later and looked to be fine, feeding happily with the group.

The next disappearing act was after 5th July. This time he failed to reappear. There was a sighting on the 28th at the aviary. Although chances are the leg rings were misread for Caûvette’s (his year-colour is black, hers is dark blue).

As he was showing no obvious signs of ill health, a possible theory behind his disappearance is lack of food. If he struggled to find food in the wild (whether due to lack of foraging skills or the foreboding heat) and wasn’t making it to the supplemental feed, he could have easily starved. If he was made weaker by the lack of food, he would become increasingly susceptible to peregrine attacks.

In fact, on one of the post-release roost checks, only one chough could be seen at Sorel as the sun set. The presence of a peregrine perched on the adjacent cliff face may account for the absence of the other choughs.

Peregrine perched below an unused chough nest box on the cliffs at Sorel. Photo by Liz Corry.

Theories aside, we have had to conclude that Han Solo is  presumed missing at this stage. Gone to a galaxy far, far away.

Heatwave

Jersey’s north coast is being hit hard by the summer heatwave. The coastal grassland has lost its lush green colour and the sheep have temporarily vacated; there just isn’t enough vegetation for them. The choughs have been fairing ok; the supplemental food compensates for the rock-hard ground.

The release site back in May before the heatwave. Photo by Liz Corry.

The release site in July feeling the effect of the heatwave. Photo by Liz Corry.

The biggest concern for them (and us) is water. The stream in Mourier Valley is currently hidden by bracken and fresh water sources in the quarry depleted. With an absolute drought declared on the Island we were concerned the choughs would turn to hazardous water troughs. Horse troughs in particular tend to be designed with smooth steep sides. A bird or small mammal can’t climb out if they fall in whilst drinking.

The stream in Mourier Valley runs almost parallel to the footpath – not that you can see it for the bracken. Photo by Liz Corry.

We always provide drinking water for the choughs in the aviary. However, the water butt dried up in back in June. Cleaning duties have been reduced to a minimum and fresh water is carried up each day for the choughs. In mid-July we had help from a few Durrell staff to get extra containers up to Sorel. Two days later it rained!

The rain didn’t last long though. We are back to rationing water until the heatwave breaks.

Insect shortages

In addition to water shortages, we have been struggling with commercial insect supplies. The company who supply the Zoo with livefood ran out of mealworms – a natural glitch in the breeding process.

When they have managed to supply mealworms, the hot weather has led to the insects over-heating in the packaging they are sent in. Trust me the smell of dead and/or dying mealworms is not a pleasant one.

Rather than a photo of dead mealworms, here is a sheep instead! Photo by Liz Corry.

The alternative of dried mealworms has not worked in the past for birds in the Zoo. They refuse point blank, some writing an angry worded tweet to the CEO. Out of desperation, we gave them a try at Sorel along with suet pellet (made with insect protein). The pressures of begging chicks and lack of wild food meant the adults had no reservations over taking the dry food.

We are still struggling with insect supplies although the order of Remiline pellet finally arrived at the end of July. Swings and roundabouts.

ReWild the People

ReWild the People circular walk from Devil’s Hole held on the 15th July. Photo by Dave Evans.

As part of Jess Pinel’s fundraising challenge of 31 activities in 31 days we hosted a circular walk from Devil’s Hole to Sorel. This was a free event open to all. Whilst taking in the sea air we discussed the Birds On The Edge project and the benefits to the public.

Aaron le Couteur, shepherd, explaining how sheep help to restore Jersey’s coastal habitats. Photo by Dave Evans.

Aaron le Couteur, the shepherd, gave a very informative talk and the choughs showed up for a bonus feed. The event was enjoyed by all and hopefully gained a few new fans to spread the word across the Island. More information about the other activities undertaken can be found here.

Choughs getting a bonus feed for the Rewild the People walk. Photo by Dave Evans.

Lights, camera, action

The choughs took part in two media projects this month. They are clearly getting used to the cameras as they were not phased by the go-pros at the feed. We hope to share some of the footage soon.

Filming the choughs at Sorel. Photo by Liz Corry.

Both filming projects will be detailed further very soon so watch this space!