This is an ongoing Western magpie behavioural issue that I can't get my head around. We have a small flock of 5 birds in our vicinity. It consists of one older male (A), a breeding pair (M&D) a young male hatched 2017 (17) and a young male hatched 2018 (18). Last year 18 had a sibling who got out of the nest a bit earlier and was picked on incessantly by 17 and eventually disappeared. This behaviour displayed can be mounting while holding the feathers on the back of the head or nape of the neck as in a sexual attack or a sort of playing jumping from side to side while holding the feathers of the head in its beak. 18 then got picked on by 17 and ended up with a lot of the feathers plucked from the back of his head, but he managed to survive. We've seen this behaviour in years previous and has resulted in the plucked bird getting badly sunburnt and eventually dying.
This year M&D have raised two chicks one of which left the nest about a fortnight ago and was immediately picked on by 18 resulting in missing feathers and damaged beak. Thats it in the photo. It sustained a damaged leg and was frequently on the ground not being able to perch properly in a tree. Its sibling remained near the nest and the parents seemed to feed both young equally. A few days ago we found the picked on one dead.
One thing I've noticed, while the young are in or near the nest they don't get picked on, the moment the leave it's on. Now the second of this years young has moved away from the nest it's its turn to be bullied but because it seems stronger and able to stay up in the trees it may not be getting hammered so badly. I don't understand how the parents can tolerate this aggressive behaviour to their young, if I aproach a young on the ground I immediatly get swooped at by the dad.
Geoff.
Great observations, Geoff.
The family & social behaviour of Australian Magpies is most interesting. You might be interested in getting hold of Australian Magpie by Gisela Kaplan. It's available from CSIRO Publishing, www.publish.csiro.au. In fact, Gisela may be interested in your observations. She's at the Centre for Neuroscience & Animal Behaviour, University of New England, Armidale, NSW.
Thanks Woko, I'm contemplating buying Prof' Kaplans book, in the meantime have emailed her with this query. I think because this present young one spent longer at the nest it's stronger than its late sibling. It is staying well off the ground, flying well and seems to faring better. I tried to get close to it with my binoculars this arvo and couldn't see any evidence of head feathers missing. Last years juvenile (No18) was giving it a bit of a hard time yesterday in a tree near the house and I managed to squirt his underpants with the hose, he flew to another branch and gave me a dirty look.
Hi there Geoff. I'm always wary about interfering with the natural behaviour of our native animals. The Magpies you've been observing have developed patterns of family & social behaviour which sustain them as a species. Using a hose to prevent one from attacking another might be providing protection to another but it might, in the long run, be intervening in a natural process. What do you think?
I agree totally with non interference but on this occasion they happened to be in a tree near where I had the hose and were low enough to the ground that the water could actually reach him. This behaviour has been going on for at least 4 seasons that we are aware of and one year no young made it to maturity. Over this time I have scoured the internet to try to find a reason behind the behaviour but no luck which is how I came to this forum. I find a lot of written works, not only about birds but other interests, are often Eastern statecentric and can have little or no relevance to WA. A couple of years ago I asked a local bird "expert" about this behaviour, he had not encountered it and his advice was that I should catch the bullied young and hand rear it. Tempting as it may sound that's not going to happen. I wonder if the sex of the young has any bearing on this behaviour? Perhaps the juvenile perceives a male baby as a potential competitor, and may not do this to a female? When we first arrived here 12 years ago the flock numbered about 7 of which 3 were female and this behaviour wasn't evident at that time. Since then two of the females have disappeared.
I think your observations are making a great contribution to our understanding of Australian Magpies, the WA variety, at least. So, I'm interested to learn what Gisela Kaplan has to say in response to you. Can you keep in touch? Many thanks, Geoff.
Very interesting observations. Kaplan's book is great, available online anywhere but I bought it as an ebook for about $20, well worth it. I know that magpies are very strongly territorial, and once the young are kicked out they have to find their own territory, and they are literally driven out by their parents. Given lack of suitable territories in urban areas, you'll sometimes find groups of young magpies sharing "unclaimed" territories. I haven't heard of multiple generations hanging around and picking so dramatically on the new broods - fascinating.
I'm not aware of any young being driven out of this flock. There have been deaths from old age, accidents and suspected poisoning where I think the maggie may have eaten a dead mouse carcase. The adult male "A" was a juvenile when we came here along with about 7 in the flock including an elderly female, blind in one eye. She was quite old but friendly and used to humans even though this was a fairly new subdivision and not many people resident at that time.
I watched them out the window yesterday when the young one was on the ground and 18 was annoying it. The father arrived with food for the kid and immediatly 18 backed off to about 3 metres away, once fed and dad wandered away 18 approached the kid but backed off again when dad changed direction and came back. This tells me that 18 is wary of dad but when he's picking on the kid and it's squawking I don't understand why that doesn't motivate the parents to hurry over to investigate. I know it's nature but this behaviour just seems counterproductive to me. What I would like to try is getting a rescued young female or two and introducing them to the flock to try to rectify gender the imbalance, currently 1 female to 4 males., but once again that would be interfering.
As Alex mentions, young are usually forced out of the territory at 8 months (according to Dr Kaplan). This can depend on group dynamic, territory size and food availability.
Male and female juveniles of the Western (dorsalis) ssp look alike. Females mature at 1 Y.O (keeping the mottled back) while males take 2-3 years before attaining adult plumage (white hind neck and back).