Chough breeding in the wild

In the wild, the choughs will start building their nests in February and March.

They use twigs to build a wide nest in a cave, crevice, or sometimes quarries and down mineshafts.

They will then line the middle of their nest with sheep's wool and moss to protect the eggs.

Choughs generally lay 3 to 5 medium-sized speckled eggs. The female tends to lay one egg perday and will begin incubating after she lays her third egg.

Nineteen days later the egg will hatch. The male's job is to make sure the female doesn't go hungry.

Once the chicks hatch they will stay in the nest for around five to six weeks. At which point they begin hopping in and out of the nest exploring the nest site.

It is a stage in their development we like to call 'bouldering'. Jumping from rock to rock. After a week of exploring they then summon up the courage to leave the nest site and take their first proper flight around the cliffs.

Chough breeding in the zoo

In the zoo we try and provide them with the same environment and learning experiences. Replicating a full size sea cave isn't possible! Instead we provide them with a nest box much larger and deeper than one we would give to a similar sized bird. We give them the same nesting material as they would find in the wild. It is very exciting to watch.

We have small cameras in each nest box so we can monitor the progress of each pair. By knowing the date the eggs are laid we can work out when they are due to hatch.

You can view the live chough nest cameras at Paradise Park by clicking here.

Below is footage from one of our nest cameras this year. This pair laid a clutch of four eggs. Sadly three of the eggs did not hatch. The video shows the very first appearance of their one and only chick. Can you see it?

 

Chough chicks only weigh about 15 grams when they hatch. They put on weight very quickly. An adult chough can weigh between 280 grams and 320 grams. Males tend be heavier than females.

Hand-rearing chough chicks

When pairs  have problems incubating eggs and rearing chicks, zoo keepers can step in and help out. Sometimes we have to artificially incubate the eggs and hand-rear.

This can be quite challenging not only because it means staying awake from 6am until 11pm to feed young chicks. You also need to ensure the chicks are not too imprinted. That means they start to think that the zoo keeper is their parent and develop behaviours a wild chick would not do. For example, sitting on a person's head!

Imprinting is more likely to happen when chicks are raised alone with no brother or sister to look to for support. We cannot release imprinted chicks as it is highly likely that they will not recognise a predator as a threat. Lots of people walk their dogs along the north coast. Whilst a dog might not want to eat a chough it could still chase one and accidentally injure it.

This video shows CeeCee a chough we hand-reared in 2015. She was the only chick to survive hatching.

We successfully hand-reared a group of four chicks in 2014. They spent the first four weeks of their life in the zoo.

This is a chick chipping through the egg shell. Can you see the bill?

This egg was rescued from a nest in the zoo because the dad was throwing the eggs out of the nest. We put it in an artificial incubator kept at 36 degrees celsius. Every day we weighed the egg to monitor progress.

It can take 24 hours for the chick to make it out of the egg. Here is the chick seconds after hatching. Looks weird right? To be fair, it is on it's back.

They need a few minutes to rest, dry out, and compose themselves before they can pose properly for photos.

We use red tweezers and wear a black glove to mimic the head of a parent chough. This is to stop them imprinting on humans hands.

We then moved them to the release aviary where we continued to hand-feed them until they fledged.

They were released in the summer of that year and are still flying free today. In fact they have paired up and started producing their own chicks!

Reintroduced choughs breeding in the wild in Jersey

This is a photo of the very first chough chick to hatch in the wild in Jersey for over 100 years. He hatched in May 2015 and was about five days old when this photo was taken.

He was named 'Dusty' because the nest was inside a building in the nearby quarry where there is a lot of rock dust from crushing granite rocks to make gravel. Luckily he didn't turn out grey and dusty. He looked like any other chough.

Dusty the wild chough chick. Note that chicks have grey to yellow bills until they are a few months old when it turns red.

This year Dusty found a female and started building a nest of his own. A good sign for a successful reintroduction. We have a totally of five wild-hatched chough living on the north coast of Jersey today.

NEWS FLASH!

This year we had seven pairs build nests in the wild. We watched the choughs collect twigs and shed wool from the fields back in March and April. The females started incubating their eggs in May and they have now hatched! We now we have at least 5 chicks,. We cannot access all of the nest sites, there could be more. We will have to wait until July to see how many fledge and begin flying around Jersey.

You can learn more by visiting www.BirdsOnTheEdge.org

Questions

  1. Where do choughs nest in the wild and what do zoo keepers do to replicate this in the zoo?
  2. How do keepers prevent chicks from imprinting on them when they hand-feed?