Carrion crow fledgling

The Carrion Crow pair in the local park have fledged two young. One of them sat on a carpet of poplar fluff, looking sleepy, and unable to fly very high. It looked like it had flown the nest a bit early. It was very tame, and allowed me to crouch by it and take his portrait. You can see that the chest and head feathers lack the metallic lustre of the adult plumage and the young's eyes are blue. The wing feathers are more metallic. A parent was nearby, furiously chasing a squirrel away. The sibling was much more active, and was intrigued by water, it opened it's bill to the water, like it was testing it or finding out what the best way of drinking was.

The inquisitive sibling. 

Collared dove fledgling

The other day I watched a Collared Dove attacking a Woodpigeon. I was a bit puzzled by this bit of seemingly random aggression, as the Woodpigeon was on its way to drink.

The following day in the same spot, a Collared Dove sat on a branch, quite low and I thought that the Collared Dove's puzzling behaviour might have to do with it's nest being nearby.

 This morning I thought that the Collared Dove was sitting in the same spot, but when I approached I noticed the fuzzy fluff and less pink plumage of a fledgling. Completely unafraid of me, it looked curious as I took its portrait.

This is the third pigeon species that I have seen fledglings this year, the first one was a Feral Pigeon, then a Woodpigeon last week. Not wasting any time!

Fledgling crow

As I took the kids to school this morning, I noticed a couple of crows on the grass on the school grounds. One of them was hunched up and I thought it looked like a young one. As I was leaving I went to check. Still looking like it would be more comfortable sitting in its cosy nest, it looked curious as I approached, and it didn't flee. It's first encounter with a camera, taking things in. As human babies, Carrion Crows young ones have dark blue eyes, which will darken to rich brown as adults. The blue eyes, pink mouth and brownish feathers help tell young from adults, but the general attitude is different too, as young crows tend to be much tamer than the adults.

The starlings jump

Today there was a clamour of 'charr!' calls from adults and fledgling starlings in my street. Several families of starlings accompanied from their noisy offspring fed on the verges. The young ones watched their parents and appear to move in slow motion compared to their frantic parents foraging on the grass and then feeding their young. Occasionally passers by would idadvertently scare the birds and the families would become separated. The young called from trees and roofs until they got together with their parents again. A fledgling spent some time on a tree, probing - in that unique starling style - with its bill open, on leaves and branches around it.

busy parent with head down and watchful young.

Calling

Probing, tasting, leaves 

Calling!

Young starlings have a heron-like look to them

Investigating

more calling!

its a big bad world out there

New moorhen chicks

This morning, a moorhen was on the island with three very young chicks. They were tiny and a bit clumsy, and had some trouble following the adult about. There was only one adult with them, so I wonder if its partner is still incubating, or brooding other chicks on their tree nest. These tiny chicks either jumped from their nest, or climbed down the tree unharmed. They peeped and flapped their tiny wings comically, stretching out to their parent, who will occasionally give them tiny morsels of food, one at a time.
 After a while the parent brooded them on the ground, a bit restless trying to get itself comfortable. The following time I saw them, the adult was trying to arrange some nesting material on a branch by the water, maybe not happy with brooding the chicks on the ground? There were a number of large gulls about, and with just one parent around, I wonder what the future of these chicks holds.

Parent finding food.

Chick begging

Brooding time

Woodpigeon fledgling chasing parent for food

I saw a young woodpigeon fledgling by the pond today, it shook its wings occasionally like young to when they demand food and I noticed an adult was nearby. The young one caught up the the parent and touched its bill, to which the adult responded by regurgitating food. The young continued chasing the adult for quite some time, regularly managing to be fed. The size different between both is quite noticeable in the top shot. 

 Young woodpigeons are much drabber, greyer than adults, without a pinkish tinge. Legs and bill also lack the red and orange hues of the adult, and the bill does not have a developed cere or operculum, the swollen covering covering the base of the bill. Young woodpigeons have dark eyes and lack the parents neck markings. Although their smaller size and black eyes makes them similar to a Stock dove, they still have the trademark white woodpigeon wing-bar.

A side view of the fledgling

I also took a video of the sequence. 

Blue tit family and Sycamore aphids

I heard the rasping begging calls of blue tit fledglings coming from a Sycamore tree, which I find it is a very common occurrence. As I approached I noticed clouds of Sycamore Aphids cascading down from the tree as the adult Blue tits moved about, searching for the aphids themselves and green caterpillars (above). It was a very impressive spectacle as the light hit the aphids and amplified the effect. The tree leaves were thickly peppered with aphids, and fledglings were having a go at finding food by themselves. One of them found a long green caterpillar and wrestled with it for a while until it was able to swallow it.

I tried to capture the density of aphids flying off around the tree in this photo.

The evenly spaced, winged Sycamore aphids (Drepanosiphum platanoidis)

A fledgling begging for food.

The adult cuts the caterpillar in half before feeding the fledgling.

This young one had caught a caterpillar on its own.

You can watch one of the adults foraging and the aphids flying off here.

Offspring recognition in Starlings

The first Starling fledglings joined their parents in the lawn of the park this morning, running behind their parents begging for food, with a cacophony of calls. Starlings are highly social birds, they like to feed together, so the chances are that the still dependent young will join unrelated young while still expecting to be fed by their parents. Furthermore, starlings in an area have synchronised egg laying so that many young will fledge on the same day. While the young are inside the nest, parents do not need to particularly recognise their offspring individually - they are likely to be their young. However, how can they make sure they recognise their offspring from others in the flock, so that they feed their own young after they fledge?
  Every year, a week or so before the fledglings leave the nest, adults start using a harsh call 'charr, charr!' (above, listen here) and the by then loud voices of the young can be heard replying from inside the nest. Why, I wondered, do they do this?
 Linda van Elsacker, Rianne Pinxten and Rudolf Frans Verheyen carried out experiments in nest box starling colonies in Antwerp (Belgium), either swapping broods of different ages for a day (Exchange experiment), or offering a choice between their chicks and alien chicks in nearby nests (Choice experiment), or swapping the nest by an empty one and relocating their nest containing young at a certain distance (Search experiment) at different chick ages.
In their choice experiments, carried out when young were 5, 11 and 16 days old, they showed that parents accepted and fed strange chicks until they were 16 days old, as shown by the weight gain of the chicks. In contrast, most parents were able to recognise their chicks when they reached 19 days, ignoring the strange ones completely, and this behaviour was found in all parents when chicks were 20 days old. So by this age adults were able to recognise their chicks.
In the search experiments they showed that the ability of parents to locate their offspring improves quickly and by the time chicks reach fledging age (20-22 days old) 97% of parents searched for and relocated the moved nest containing their young within an hour of the nest having been moved.
 The constant calling by parents and offspring in the days before fledgling might be a way of reinforcing this recognition. So, by the time the offspring are ready to fledge, and then mingle with other chicks, parents are able to recognise their offspring, presumably by their calls.

More information

Frans Verheyen, R., Van Elsacker, L., & Pinxten, R. (1988). Timing of Offspring Recognition in Adult Starlings. Behaviour, 107 (1), 122-130 DOI: 10.1163/156853988X00232

Chaiken, Marthaleah (1992) Individual recognition of nestling distress screams by European starlings (Sturnus vulgaris). Behaviour : 139-150.

Young starling looking for food this morning

...and chasing its parent begging.

Fledglings

In the last couple of days I've come across a number of resident species with fledglings. Blackbirds were first, a short-tailed adventurous chick calling for food in the park, last week (below) and today (above) a Robin yesterday and a Song Thrush and Dunnock today. As the youngsters jump from the nest, they have to face a steep learning curve, they are more or less naive to predators, so in these days between fledgling and independence from parents they need to learn about them and also perfect their foraging skills, usually while they follow their parents, begging.
 Magpies and Carrion Crows start showing an interest on trees and bushes, listening for calling chicks, so the alarm calls of the adults, associated to the different predators are part of the learning process. The first mallard brood in the park has already disappeared, probably due to predation by Herring and Lesser-black backed gulls.

Blackbird fledgling, 29/04/2014, from the same brood as the top photo, today.

These goslings from a local park already show a great interest in people, usual food providers here.

Young Robin

A sleepy Dunnock fledgling

A song thrush finding food for its youngster...

Young Song Thrush fledgling and busy parent.

A Magpie in search of nests or young birds in the undergrowth.

A Herring gull in the park having mallard for breakfast this morning.

Woodpigeon school

I have come across several Woodpigeon families in the last week. August and September are peak season for Woodpigeon fledglings. One or both adults will accompany, and occasionally feed the young for a week or two. The fledglings look nervous and follow each other or their parents, feeding on the ground. After the adults leave them to their devices, the usually two siblings will move together or join other juveniles.
 In these photos, you can see the differences between the juveniles and the adult at the background. Juveniles are much smaller, they lack of white patch on the neck (but not the striated neck feathers), the beak is a dull grey and their eyes are dark.

Watch and learn

I watched a pair of Carrion Crows with a juvenile today. From a distance, you would say adults and young look the same, but young ones appear smaller than the adults, have a thinner bill, and lack the purplish-blue sheen of the adults feathers, with an overall impression of a dull, dark brown bird. The young one today followed one of the adults carefully, watching his every move, often having to trot to keep pace - even if the adult seem to walk normally. If the adult appeared to find a morsel, the young one begged, bill open and wings flapping. Crows being such adaptable birds, the young ones have lots to learn on how to find food. About three months after fledging, the young crows will become independent.