Monthly Archives: May 2020

Fostering and Feuding

Fostering…

Our five nests produced fifteen eggs. Eight of these have hatched and all eight chicks are doing well – after a couple of hiccups…

On May 10th, we noticed the third chick in nest five was very small (16 grams), and in danger of being pushed to the bottom of the nest by its siblings. There were four overdue (infertile) eggs in nest three, so we decided to foster the small chick to this nest. The female in nest three was still patiently sitting, and she was expecting to see eggs hatching. We gave her what she wanted.

Chick from nest five being put into nest three along with egg shell
Chick from nest five being put into nest three along with egg shell

We put the chick in the box using the hatch at the back – Ali was in the aviary putting in live food and distracting the adults. The parent birds both went on top of the nest box, as they have been conditioned to do.

As well as the chick, we added a piece of egg shell. This mimics real-life events, and the normal reaction of the female should be to come in and take the egg shell away. If she did this, we would know that she would accept the young chick as her own.

Female removing eggshell - Success!
Female removing eggshell – Success!

As soon as Ali had left the aviary, the female returned to the nest and very gently removed the shell. Moments later, the male hopped into the nest to inspect the new arrival and left. The female then came back in and started to brood the chick. Success!

The chick is now over two weeks old, and is progressing well – getting food from both parents, and gaining weight.

Feuding…

Events were not as joyful in nest two. On the evening of May 15th the male parent became very agitated and started to attack the female – and the three young chicks. Luckily, we had spotted this while monitoring at home, and decided something had to be done.

Male attacking female and chicks in nest two

It was getting dark, and soon we would not be able to get into the aviary without disturbing all the other nesting pairs nearby. However, staff were on hand (staying on site due to the lockdown), and got in quickly to catch the male. He spent the night in solitary confinement, and was relased the next day into the large polytunnel group.

On checking our records we found this male had done exactly the same thing in 2015 – on the exact same date – very bizarre!

We believe male choughs at this time of year are “pumped up” and ready to spend sixteen or more hours a day searching for food in the wild. This is something we try to replicate in the aviaries by hiding food, giving the males some distraction.

Nest Totals

Nest 1 has two chicks. One egg did not hatch

Nest 2 has three chicks. One egg did not hatch. Mister chough has left home.

Nest 3 has one adopted chick from Nest 5. Four eggs were infertile.

Nest 4 has no eggs.

Nest 5 has two chicks (plus the third which is in Nest 3). One egg did not hatch.

Total to date is eight chicks, most being two weeks old.

Fifteen Eggs

Fifteen Eggs – So Far

Our first chough egg was laid on April 9th. Since then four nests have been filled up with clutches of various sizes. Choughs will lay up to five eggs in a clutch, with sizes diminishing with age of the adult female.

Fifteen Eggs
Four chough nests with eggs

Nest 1 started on April 12th, and now has three eggs.

Nest 2 has four eggs, laid between April 15th and 21st.

Nest 3 has four eggs, laid between April 9th and 15th.

Nest 4 is still being constructed – there may not be eggs forthcoming.

Nest 5 has has four eggs laid between April 13th and 18th.

We know that our captive choughs (and probably choughs in the wild) start incubating full-time when the third egg is laid. This delays the development of the first two eggs, so as many chicks as possible can hatch together. This means they are of similar size, and have more equal chances of survival.

Using the 18 – 19 days of incubation estimate, our first chicks should be hatching on May 3rd or 4th.