We have a family of Wagtails on our property but my husband is convinced that their agressive behaviour is actually chasing away other birds. We often see them pecking and acting agressively to many of our other birds including kookaburras, kingfishers and even ducks.
We would appreciate some feedback as to whether the Wagtails can actually become a pest. Thanks, Rhonda
Hi Rhonda. My experience of Willie Wagtails is that they're aggressive during breeding season when they're defending their nests & their young. There are still adults with young at my place. Is this the case at yours?
Hi Woko, yes, the parent does have young but the aggression has been happening for quite a while and not just since the young hatched.
Hi Rhonda (I apologise in advance for the long post!),
I don't know of any evidence to suggest they could become a pest - they are a small insect-eating bird and can do no more harm than simply annoy every single bird near it's nest. Other birds find this harrassment merely irritating and as far as I'm aware, it has no affect on them.
Pest birds are usually flock birds (not always) which are either agressive (even when not breeding) and/or take advantage of habitat alteration, and therefore take nest sites, displace indigenous birds etc (ie Noisy Miner, Rainbow Lorikeet). In the case of the Noisy Miner they don't just "harrass" other birds, their sheer numbers and hostile nature, exclude less adaptable species. Sulphur-crested Cockatoo's have become very abundant in many places because they have adapted so well to European settlement. Willie's have also benefitted from opening up of habitats but not to the point of becoming a pest.
For a bird to be considered a pest they have to: cause signifcant damage to crops/orchards or disrupt/displace other species etc. Pest birds are usually larger birds.
Small insect-eating birds such as the Willie Wagtail don't form large, permanent flocks and don't have the above qualities. So in my opinon, they don't have a potential to become a pest.
Thanks for your comprehensive reply Owl. In our 'flock' there are about 8 which we think are two families. Think at this stage we'll just keep an eye on them and see how they go.
I'd love to hear what happens Rhonda and whatever the case, Willie's are always a joy to watch.
Rbuddy, I suspect that rather than being a pest your Willie Wagtails are doing what Willie Wagtails do. Birds will always compete for territory & other resources as well as defend their nests & young ones. Enjoy observing them in action.