Chough report: August 2020

New recruits mixing with the flock. Photo by Liz Corry.

The results are in!

We finally finished ringing the young choughs at Sorel by the second week in August. Part of the ringing process includes collecting DNA samples to send to the UK for identifying sex. The results came back relatively quickly. We have three males and nine females. Overall, this means we still have an imbalance in the population. Roughly one male for every two females. The good news is that, providing they make it through the winter, we could be looking at fifteen pairs for the 2021 season.

Jinxed Mauve

I spoke too soon. One of the 2020 males sadly died this month. He had not shown any indications of being sick until one of the ringing catch-ups. He wasn’t the target, just found himself in the group locked in and had to be hand-netted. Once in the hand we could hear his breathing wasn’t right.

It was Sunday evening and with no vet nearby. I decided to release him and then re-catch the next day with a vet in tow. Big mistake. The weather (thunderstorms), the aviary (jammed hatches), and the bird’s stubbornness all played against me. When I could try catching, he would simply sit outside watching the others go in. Only moving when I walked to the brow of the hill, clear of the hatch doors.

Evading capture. Photo by Liz Corry.

He still wasn’t looking ill, sneezing, or open-mouthed breathing as they would with a Syngamus infection. However, a phone call on the 17th from Ronez proved otherwise. He had been found dead in the bottom quarry. His post mortem revealed no obvious signs of Syngamus or Aspergillus. He had thorny-headed worm present just not in any numbers to cause fatality. Another unsolved mystery for the chough history books.

Chough bling

I order a new a batch of leg rings each year. One leg ring represents year of hatch and each year has a specific colour. We are now in the seventh year of choughs breeding in the wild and the colour options are becoming limited. We also struggle with quality from the supplier hence a lot of replacements are required.

The plastic striped ring and the numbered metal ring provide information that this is a Jersey chough, Photo by Liz Corry.

I invested in a batch of colour rings with text written on. Theoretically, each chick is accessioned with a PP number in the ZIMS database. This PP number would be on their plastic ring so, theoretically, we would need just one ring for year and individual instead of the current two.

Note I keep saying theoretically. The chaos that COVID-19 caused with our monitoring meant this plan was side-tracked. The first batch I ordered arrived in time for the start of ringing. Only we couldn’t use them. The manufacturer had printed the text in black not white on a dark blue ring. Totally illegible.

The next batch (different manufacturer) arrived too late. However, I did end up using one on Danny. Danny, for those who haven’t read July’s report, was given a pale blue leg ring. We already had a chick with pale blue on the other leg. When Danny found himself in a hand-net again this month, I swapped his ring for one of these new ones. It’s a bluer blue than the old pale blue. Stands out a treat.

A new pale blue coded leg ring will make Danny stand out in the crowded flock. Photo by Liz Corry.

I also looked into a new style of plastic ring; clip-on rings. Used widely amongst pigeon fanciers and super easy for a 3D printed mass market. The keepers in the Zoo have started trialling them on the red-breasted geese. For the choughs they look ideal as we can glue the clip shut much like we glue the current wrap-around rings. Alas, I was let down again by delivery times. The fit of the ones that arrived were a millimetre too tight. Sounds negligible yet makes a huge difference. Just the same as the rings we wear.

Back to the drawing board for next season. Will have to add leg rings to the chough’s Christmas wish list.

Home visits

A few noteworthy public sightings came in this month.  Max Allan, retired vet well known to many Islanders, had ten choughs land on his roof in St John. They normally try and avoid vets! Not sure if he charged for their visit.

Durrell’s former CEO, Paul Masterton, emailed in photos of three choughs visiting his neighbour’s house. This was somewhat fortuitous as it might well be the only bit of evidence we have of Trevor and Noirmont having successfully fledged a chick this year.

Choughs stopped by to pay a visit to Durrell’s former CEO this month. Photo by Paul Masterton.

Noirmont and a chick were photographed on the roof of the house. The chick was one that Glyn had caught and still needed the other rings to be fitted. We were having difficulty assigning parents to this chick as we hadn’t seen it being fed by anyone. 

It would seem unlikely for Noirmont to travel without Trevor. If we assume he was the third bird it suggests this chick belongs to them.

North East explorers

A pair of choughs have been sited on several occasions flying over Rozel Valley. The Rozel sightings cluster around la Ferme farm a dairy farm home to 280 Jersey cows. If a pair of choughs are looking for a new home then la Ferme’s buildings and the surrounding  grazed land offer a favourable choice. Neighbouring attractions, if this was an ad in Chough Property Monthly, include horse-grazed paddocks and scenic clifftops.

La Ferme Farm, Trinity, is located in the north east of the island. Image from Google Maps.

Back in February I saw a pair of choughs from my garden flying over Rozel valley.  This month I saw the same thing. Maybe even the same pair? They spent a fair amount of time dipping in and out of sight possibly landing to feed. An hour later they flew by again this time from the direction of Rozel Bay over to White Rock.

These could be the same choughs seen at Farmers Cricket Ground last month and again this month.

Flying further afield

COVID-19 has prevented a lot of zoos from importing and exporting animals as part of their collection management. The two choughs we bred at Jersey Zoo in 2019 were due to travel to Paradise Park, Cornwall. This was put on hold in lockdown and the birds housed in off-show aviaries so Penny and Tristan could start their new family. 

On 25th August, along with several birds of other species, the chicks finally made their way across the channel via ferry. These two girls can now become part of the UK breeding programme.

And, just because they haven’t featured in a while….