Naturally occurring metals and metalloids [metal(loid)s] are essential for the physiological functioning of wildlife; however, environmental contamination by metal(loid) and plastic pollutants is a health hazard. Metal(loid)s may interact with plastic in the environment and there is mixed evidence about whether plastic ingested by wildlife affects metal(loid) absorption/assimilation and concentration in the body. We examined ingested plastic and liver concentration of eleven metal(loid)s in two seabird species: fairy (Pachyptila turtur) and slender-billed prions (P. belcheri). We found significant relationships between ingested plastic and the concentrations of aluminium (Al), manganese (Mn), iron (Fe), cobalt (Co), copper (Cu) and zinc (Zn) in the liver of prions. We investigated whether the pattern of significant relationships reflected plastic-metal(loid) associations predicted in the scientific literature, including by transfer of metals from ingested plastics or malnutrition due to dietary dilution by plastics in the gut. We found some support for both associations, suggesting that ingested plastic may be connected with dietary dilution / lack of essential nutrients, especially iron, and potential transfer of zinc. We did not find a relationship between plastic and non-essential metal(loid)s, including lead. The effect of plastic was minor compared to that of dietary exposure to metal(oid)s, and small plastic loads (< 3 items) had no discernible link with metal(loid)s. This new evidence shows a relationship between plastic ingestion and liver metal(loid) concentrations in free-living wildlife.

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Abstract. Brachyscome ciliaris is a floriferous Australian native daisy, with potential for use as a horticultural species. The species is hardy and seeds are relatively easy to germinate, but it is unique within the Brachyscome genus in that seeds are distinctly dimorphic. Within a fruiting capitulum, ray seeds are smooth and narrow with a minute pappus, whereas disc seeds have broad flat wings with curled hairs and a longer pappus than that of ray seeds. Both seed morphs, collected from five populations of the species, were tested to determine differences in their morphology, germination speed and percentage, seedling growth and wind-dispersal characteristics. Ray seeds were generally lighter and smaller than disc seeds and their length varied significantly with provenance. Dormancy levels of the two seed morphs and growth of rayand disc-derived seedlings did not differ significantly, but differences were significant among the five populations tested. Seeds germinated readily, and germination was optimal under winter or summer conditions and lower in spring or autumn. Seed production by plants raised from ray or disc seeds was identical, but Noora-sourced plants yielded more seed than did plants sourced from the other provenances tested. Seed size, germination and plant growth of B. ciliaris varied significantly among populations. Winged disc seeds were dispersed slightly further by wind than were wingless ray seeds. We concluded that dormancy, germination and seed-yield characteristics of B. ciliaris were all influenced more by seed provenance than by seed morph (ray or disc).

Gibberellic acid (GA3) is routinely used as a germination stimulant for seeds. However, the methods used to dissolve GA3 powder – particularly if using organic solvents – have the potential to affect germination outcomes. In this study we examined the influence of the solvent ethanol, used to dissolve GA3, on the seed germination of 14 species of Brachyscome and two species of Allittia. These species are important Australian native composites with potential for use in habitat restoration. Seeds of 11 of these species were found to be particularly responsive to GA3. However, the use of a low concentration of ethanol (0.5%) to dissolve GA3 affected subsequent germination outcomes, with four species responding positively and eight negatively to this solvent. The pure effect of GA3 was therefore masked by the presence of small concentrations of ethanol, whose effects varied between the species examined. Because of these potentially confounding effects of ethanol, we recommend the use of pure water for dissolution of GA3 when testing seed germination responses in these genera.

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