Last year (2018) we have had considerable problems with Ravens raiding the Wood Duck nest boxes before the ducks start sitting, and so they are not around to defend their nests. Of 5 earlier nesting attempts by Wood Ducks in 2018, all were raided such that 1-20 eggs were destroyed per nest, three by Ravens, and two by Brushtail Possums – before I discovered the ability of possums to cross by even the flimsiest twiggy branch.
I then quickly painted several duck-sized nest boxes with the colours of our woodland tree bark with the idea that this would make the boxes less obvious for daytime bird predators, and moved the boxes to more discrete locations well away from the (known by predator birds) raided boxes, and with no close twiggy branches – possum risk. I copied this strategy for as many as I could of the parrot-sized boxes also at the same time. By this stage most of the interested ducks had given up and left, however one pair selected a relocated newly painted (boobook owl design) nest box. All 8 of their eggs hatched and launched to the ground where the parents were waiting.
Late in the nesting season, we had a large amount of rain that instigated renewed interest in nesting by our local Wood Ducks. We then had three newly sitting Wood Duck pairs, in the relocated nest boxes. Actually there was interest (duck droppings) displayed in non-duck sized nest boxes that clearly were in desired locations, so I quickly switched the vacant large parrot sized boxes out with duck-sized boxes that had been installed elsewhere.
In less than a week the first egg was laid in one of these switched boxes. It pays to keep a close eye on things! The one successful and newly vacated duck-sized nest box was cleared of eggshells and first egg laid within days of its vacancy. Only one of the selected boxes is painted – I was quite demoralized at that time and only painted a couple of duck boxes before discovering that the ducks had given up ideas of nesting. I spent the rest of my efforts rapidly painting the parrot boxes, as they were very much interested in raising families. The flock of Ravens have not visited our property much in the recent weeks.
While I have no camera imagery or personal observations relating to risks posed by Currawongs to our nest box residents, I have seen Currawongs in the past raid nests for eggs and chicks. Interestingly, all except one Rosella family has selected a nest box with a small parrot-sized entrance, that would prevent Currawong access.
The Rosella family using the nest box with a larger parrot-sized entrance (King Parrot design) at that time had no other choice as all smaller entranced nest boxes were taken, except one that stank of the Brushtail Possum that I had previously evicted when installing possum guards on the tree. The one Tree Creeper nest box is located in a small leafy stand of trees with plenty of hiding ability from prying eyes. I’m sure a Currawong would love to snack on a Tree Creeper adult or just-fledged young. The tiny nest box entrance provides protection for eggs and chicks.
Having all the parrot nest boxes installed on solitary trees away from cover with no close first-launch fledgling options bothers me, as being a significant risk for predation by Currawongs. I will seek to experiment to find options to exclude all types of possums, for installation locations with protective cover of leafy branches to protect nests from predator birds like Ravens and Currawongs.
Back to the Predator and Competitors page: