My thoughts about the story related to several species of our birds that actually regularly include this pest in their diet, including Noisy Miners, Yellow Wattlebirds, Grey Shrike-thrush and the ubiquitous Silver Gull, but I suspect there are several others. The miners and wattlebirds almost certainly don't target them, but encounter them when both are attracted to flowering
eucalypts. Shrike-thrushes and gulls certainly do, as I recount below.
While birding in the Meehan Range, I came across a pool of water that had collected in a wheel rut and flushed a shrike-thrush from the water's edge. Cursing that I had missed a photo opp. by my lack of vigilance, I was surprised when it quickly returned to the poolside. Over the next several minutes I photographed it on the ground and in the nearby scrub, and despite repeatedly flushing it, it was always drawn back to the pool, but didn't appear to drink. Later, looking more closely at the pool I noted that there was a procession of wasps visiting the edge of the water, presumably to drink. It was then that the penny dropped, the shrike-thrush wasn't drinking but had found a great source of 'easy' food--the wasps.
I had noted and blogged a previous occasion that I had witnessed Silver Gulls targeting wasps, and a few days ago I took the accompanying images of a similar event, this time on Bellerive waterfront. I suspect that it's a regular occurrence. Several gulls lined up, some few metres apart, on the river's edge, facing towards the sun, probably to silhouette the prey. Individual w
From all this a few questions arise. Where are the wasps going to (they're heading off across the Derwent River), or for that matter where are they all coming from, as there was a fairly constant procession of them? Why do the gulls bother with them as they would appear to have very little nutritional value?
Excellent images that portray a story
ReplyDeleteThanks Iain. I would have liked to have better shots of the event, but my reflexes aren't up to it! It's not for want of trying. Given that Silver Gulls, indeed most gulls are scavengers, taking anything that's even half edible, I shouldn't be surprised that they chase wasps. I managed to kill about ten at a recent BBQ at the Waterworks Reserve. I was concerned that they might get into open cans of the kids cordial, with potentially serious consequences.
ReplyDeleteOn the subject of eco-friendly pest control another media story on the current mouse plague springs to mind. How many of us are lucky to live in areas where the residual habitat sustains a population of Boobook and Masked Owls to help keep the rodent population down.
ReplyDeleteHow exciting to find this out. Great photo's. Wasps may have little nutritional value but I'm sure glad that gulls eat them.
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