https://ogma.newcastle.edu.au/vital/access/ /manager/Index en-au 5 https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:37964 Wed 14 Jul 2021 08:29:30 AEST ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:47630 Acridotheres tristis). Methods: We used a reduced genome representation method (DArTseq) to generate thousands of single nucleotide polymorphism markers in 462 common mynas. We then applied population genomic techniques to identify the common myna's population attributes such as gene flow, genetic diversity, and effective dispersal, all of which are critical for understanding geographical range expansion of pest species. Results: We found significant genetic structuring across the common myna's Australian distribution, indicating limited levels of effective dispersal amongst the populations founded from historic introductions in the 19th century. The historic introduction points were found to be genetically distinct, such that in the region on the invasion front where admixture did occur, myna populations exhibited higher genetic diversity than in the source populations. Significant isolation by distance was evident amongst populations derived from the same founding population, with genetic diversity decreasing moving away from the point of colonization, and in general, higher levels of gene flow from source to front than vice versa. Main conclusions: This study indicates that despite a 150-year colonization history of mynas in Australia, contemporary genetic structure still largely reflects human-mediated dispersal. However, expanding populations are now connecting and the consequent increased genetic diversity may improve evolutionary potential. These results suggest that more management focus should be directed towards the invasion fronts, rather than the large, historic source populations.]]> Tue 24 Jan 2023 14:16:33 AEDT ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:7456 Sat 24 Mar 2018 08:38:51 AEDT ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:7543 Sat 24 Mar 2018 08:37:43 AEDT ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:9719 Sat 24 Mar 2018 08:34:37 AEDT ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:20636 Sat 24 Mar 2018 07:55:47 AEDT ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:4893 Sat 24 Mar 2018 07:22:00 AEDT ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:42509 Acridotheres tristis) and measured eye patch coloration as a function of the food combinations individuals selected. Mynas had access to either water or carotenoid-supplemented water and could either eat a standard captive diet or choose freely between three nutritionally defined pellets (protein, lipid or carbohydrate). Mynas supplemented with both carotenoids and macronutrient pellets had higher color scores than control birds. Male coloration tended to respond more to nutritional manipulation than females, with color scores improving in macronutrient-and carotenoid-supplemented individuals compared with controls. All mynas consuming carotenoids had higher levels of plasma carotenoids, but only males showed a significant increase by the end of the experiment. Dietary carotenoids and macronutrient intake consumed in combination tended to increase plasma carotenoid concentrations the most. These results demonstrate for the first time that consuming specific combinations of macronutrients along with carotenoids contributes to optimizing a colorful signal, and point to sex-specific nutritional strategies. Our findings improve our knowledge of how diet choices affect signal expression and, by extension, how nutritionally impoverished diets, such as those consumed by birds in cities, might affect sexual selection processes and, ultimately, population dynamics.]]> Mon 28 Nov 2022 15:02:47 AEDT ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:40189 Acridotheres tristis. Here, we aimed to test the extent to which shared functional traits inform the intensity of aggression between cavity-nesting birds. We quantified the outcomes of aggressive interactions between birds in large hollow-bearing trees in SE Queensland, Australia. We examined whether more similarly sized birds interacted more frequently, whether larger species won aggressive interactions more often, and whether cavity-breeding species with similar preferences for nesting sites (breeding-niche space) interacted more frequently. We recorded a total of 410 aggressive interactions and 48 interacting bird species around tree hollows, including 20 cavity-nesting bird species. These interactions were dominated by the invasive common myna, the native noisy miner (a non-cavity-breeder) and the native rainbow lorikeet Trichoglossus moluccanus, but the common myna won the largest total number of interspecific interactions. On average, larger birds won aggressive interactions more frequently, yet there were some important exceptions to this finding; the common myna (113 ± 30 g) won 26 of the 29 interactions against the larger native rainbow lorikeet (126 ± 44 g). Importantly, species with more similar nest-site preferences were observed aggressively interacting more frequently. Synthesis and applications. The impact of the invasive common myna was higher-site preferences. Control efforts for the myna should focus on birds that nest in natural tree hollows. An analysis of shared traits by managers could be used to help identify how many local species would benefit from common myna control in a given area and test if further behavioural studies of common myna are warranted.]]> Fri 22 Jul 2022 14:02:27 AEST ]]>