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!

3 thoughts on “Chough report: July 2018

  1. What a remarkable success this reintroduction of the Chough has been. And my congratulations to all those who have been involved with the breeding of them in a captive environment, and the detailed monitoring of the now wild population.. Jeremy Mallinson

  2. This project is going from strength to strength. Congratulations to the team. These rewilding projects are not easy and it due to the diligence of Liz, Glyn and team that it has been so successful. It is becoming a showcase example.

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