Who likes fresh olives? It turns out that some of your Park Lands possums really love them, and others don’t.
Here’s the latest report from our Park Lands possum researcher, Tara McKenzie:
After seeing how closely the ringtail and brushtail possums were cohabitating in the south-eastern Park Lands, we were concerned about whether the two species may be competing for food and shelter resources.
Illustrations: Kevin Stead, Australian Geographic
However, after observing the two species along East Terrace, we have seen that the two species fill two closely related, but distinct enough niches within the ecosystem to coexist happily.
Here is an example: Along East Terrace at Victoria Park, there is a long line of old-age gum trees.
River red gums (Eucalyptus camaldulensis) in Victoria Park / Pakapakanthi (Park 16) near East Terrace. Pic: Shane Sody
Normally, we would expect to find brushtail possums all through these trees, with maybe a few ringtails, as these trees have large hollows for shelter and produce new foliage, flowers and fruits year-round to keep the brushies fed.
However during our surveys, we have not observed a single brushtail in these trees, but many ringtails. This seemed strange until we reached the grove of olive trees on the corner of East Terrace and Wakefield Road - brushtail central!
Some of the 1870s olive trees (Olea europaea) near Wakefield Road in Victoria Park / Pakapakanthi (Park 16). Pic: Shane Sody
Throughout this area, we observed brushtails foraging for fallen olives on the ground and feeding in the trees. We normally observe Park Lands possums fleeing straight back to their den when we approach, but in this grove, filled with such a high value food resource, the possums retreat into the canopy and return to the ground immediately when the danger has passed.
This showed us that ringtails prefer areas where flowers and leaf tips are plentiful, whereas brushtails will move beyond their typical range, risking predation and other dangers, when high value foods, like olives (or our backyard fruit and veg gardens), are available.
This is a great example showing how brushtails are driven by resources and will easily adapt to be able to utilise these resources.
I am also continuing to trap in the Park Lands and in contrast to the poor condition animals I was catching towards the end of last year, last week I caught two extremely healthy individuals.
I caught a young adult male, weighing 2.5kg - the second heaviest I have caught in my entire project, who was in great condition and a older female, again in great condition with a healthy and thriving joey.
Joey brushtail possum in the pouch. Pic: Tara McKenzie
Look carefully at the right-hand photo: the joey’s leg is sticking out of the pouch! Pics: Tara McKenzie
It is really interesting seeing the contrast between individual animal health across the Park Lands and I am looking forward to unearthing why these differences are occurring.
Tara McKenzie is a University of Adelaide researcher, studying brushtail possums both in the Riverland, and in your Adelaide Park Lands.
Her research includes an internship with the Adelaide Park Lands Association where her main role is to collect information about the plant and animal species that are found across your Park Lands, with a focus on those that have an important role in possum habitats.
