Election 2016 is heating up! The major parties are presenting some opposing policies (and one has finally released a policy for threatened species conservation), but are the voters really that bipolar? Surely they might respond, at least in part, to multiple policies across party lines….?
I’m using this analogy to try and say something about ecological disturbance (stay with me). One ‘party’ advocates for herbivory and another ‘party’ advocates for fire as the key important disturbance that the ‘voters’ (read: small vertebrates) will respond to. But these two disturbances interact with each other, and animals might respond to these interactive effects….So it might not be as simple as one or the other, but a combination of both?
That’s what investigator Claire and her team thought, so they packed up their gear, went down to Booderee National Park, and set up a full-factorial field experiment that manipulated herbivory (fenced / unfenced) and fire (burnt / unburnt) in combination.
Perhaps not surprisingly, there was a strong synergistic effect of herbivory and fire on vegetation – those sites that were burnt had poorer vegetation recovery where large herbivores were not excluded….. Same story with the small animals?
Nope. Some were more active where herbivores were excluded, regardless of whether or not the site was burnt, while others were more active where there had been a fire, regardless of whether or not herbivores were excluded.
So looks like animals are sticking to the policies of just one party. Both disturbances are important overall, but individual species were only responding to one or the other.
For the actual science of this story, you should definitely read the paper (it’s open access!) and contact the authors if you have any questions.
Foster CN, Barton PS, Sato CF, Wood JT, MacGregor CI & Lindenmayer DB (2016) Herbivory and fire interact to affect forest understory habitat, but not its use by small vertebrates. Animal Conservation 19, 15-25.
K!E#20 by Luke S. O’Loughlin