Abstract
I aimed to better understand the community ecology of sympatric birdlife in subtropical South East Queensland, Australia using patterns of temporal species co-occurrence and principles from network theory. In line with expectation, a hierarchical clustering analysis showed that sampling dates that were successive possesed similar patterns of observed bird species. Interestingly, there is an example of total observed bird biomass being almost identical (38 kg) on successive days in September, but comprising 36 species on the first day yet only 8 on the second, the latter date being dominated by biomass from a single species (Australian Pelican, Pelicanus conspicillatus). Ranking each species on its average pairwise correlation to the other 87 species in the set shows that, unsurprisingly, raptors (such as Whistling Kites, Haliastur splenurus) tend to be enriched at the extreme negative end of the list (hypergeometric enrichment statistic P = 0.00029) indicating their presence is inhibitory to other avian species. On the other hand, Silvereyes (Zosterops lateralis) possess the highest number of total connections, the highest radiality (or ‘network influence’) metric within the inferred co-occurrence network and have the second highest average positive correlation to all other bird species in the set (+0.32). Collectively, this suggests Z. lateralis can be seen as an indicator species whose presence indicates an enhanced likelihood of observing a diversity of other bird species. The use of the PCIT network reconstruction algorithm is demonstrated in ecology for the first time.