By Charlotte Dean

Wind, rain & DIY!

The wind and rain have been battering the aviary a lot this month, so the keepers have been kept hard at work carrying out regular aviary structure checks, keeping the hatch wires tight and tying down and fixing any loose panelling. With all these strong winds, the aviary definitely has a low groan, while still standing strong. Thanks to the strong winds and heavy downpours it’s been a month of aviary surprises. As you will see in the photograph, one of our release hatches broke at the hinges – just goes to show how windy it has been! Thankfully, it wasn’t a hatch that is regularly used so it didn’t cause any harm to the keepers or the birds. The hatch was fixed but will eventually be replaced with a new one in the New Year. Considering the aviary was built almost 10 years ago, it is surprising that it doesn’t have more wear and tear and, despite the terrible weather, it is quite clear that it doesn’t stop the choughs from having fun!

Colour-rings

It has come to that time of year when colour rings start dropping off our choughs; this is most likely caused by the drastic change in temperature making the already long worn colour rings brittle enough to fall off. This in turn can bring identification concerns, but nothing a catch-up and re-ring can’t fix! If we can catch them that is. We have recently had a few of our adults fly into the aviary with colour-rings missing but thankfully these are some of our pairs and, therefore, it’s easy to know who’s who by identifying the other bird in the pair. We can just be thankful though that they’ve been lost and haven’t caused any ring-related issues. As choughs are relatively large birds, we use ‘wrap-around’ plastic rings which can, luckily very rarely, trap toes and/or claws; but in most cases, other ring options can have similar problems.

When a chough has its toe and/or claw stuck in a colour-ring, it doesn’t worry the keepers too much as this is a common occurrence for some birds. Furthermore, trapped digits are often more common in female choughs during the breeding season as their rings get stuck while they’re incubating. However, the birds generally manage to correct themselves without the keepers intervening. At the moment, however, we have a two adults in the flock that have their digits stuck in their colour rings, which we are closely monitoring. So far, they’ve not shown any signs of injury, but it may be that they will be caught up in the near future if the problem doesn’t naturally correct itself.

Juveniles catch-up

An attempt was made at the end of November to catch some adults with plastic ring issues; however, as ever, the adults outsmarted the keepers and flew away before they had a chance to set up! As we had arranged a ‘back up’ of other happy helpers to the aviary, we took the opportunity to catch some unsuspecting juveniles that let their hunger get the better of them by entering the aviary. So, five of the thirteen 2022 chicks were caught in the aviary. Although the newest additions to this wild populations have already been given names, we took blood samples from the briefly held juveniles to find out their sexes! The first five choughs caught, and blood sampled were: Willow, Liberty, Pine, Sallow & Birch. The blood samples themselves will take a few weeks to be processed and for us to receive the results. However, on visual observations, some choughs are more obvious through sexual size dimorphism than others. Male choughs are generally much heavier and larger than female choughs. On close inspection it became very clear that Sallow is a very large bird and most likely a male, it was the largest of all five caught. Portelet, a female which hatched in 2020, has been warming to Sallow of late and was spotted waiting outside the aviary for Sallow’s release. This brings great hope for a new pairing of Sallow & Portelet in the near future. Birch was quite average in size, however, but like Sallow & Portelet; Chewbacca was also seen waiting outside the aviary for its release so there could be another pair on the horizon. In the meantime, watch this space!