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Introduced Marine Pests (IMP, = non-indigenous marine species) prevention, early detection and risk-based management strategies have become the priority for biosecurity operations worldwide, in recognition of the fact that, once established, the effective management of marine pests can rapidly become cost prohibitive or impractical. In Western Australia (WA), biosecurity management is guided by the “Western Australian Prevention List for Introduced Marine Pests” which is a policy tool that details species or genera as being of high risk to the region. This list forms the basis of management efforts to prevent introduction of these species, monitoring efforts to detect them at an early stage, and rapid response should they be detected. It is therefore essential that the species listed can be rapid and confidently identified and discriminated from native species by a range of government and industry stakeholders. Recognising that identification of these species requires very specialist expertise which may be in short supply and not readily accessible in a regulatory environment, and the fact that much publicly available data is not verifiable or suitable for regulatory enforcement, the WA government commissioned the current project to collate a reference collection of these marine pest specimens. In this work, we thus established collaboration with researchers worldwide in order to source representative specimens of the species listed. Our main objective was to build a reference collection of taxonomically vouchered specimens and subsequently to generate species-specific DNA barcodes suited to supporting their future identification. To date, we were able to obtain specimens of 75 species (representative of all but four of the pests listed) which have been identified by experts and placed with the WA Government Department of Fisheries and, where possible, in accessible museums and institutions in Australasia. The reference collection supports the fast and reliable taxo

Nickel compounds are widely used in industries and have been massively introduced in the environment in different chemical forms. Here we report the effect of two different chemical forms of nickel, NiCl2 and nickel nanoparticles (NiNPs), on the reproduction of the marine calanoid copepod Acartia tonsa. The behavior of nickel nanoparticles was analyzed with different techniques and with two protocols. In the “sonicated experiment” (SON) NiNP solution was sonicated while in the “non-sonicated experiment” (NON-SON) the solution was vigorously shaken by hand. Final nominal concentrations of 5, 10 and 50 mg L−1 and 1, 5 and 10 mg L−1 NiNPs were used for the acute and semichronic tests, respectively. Nanoparticle size did not change over time except for the highest concentration of 50 mg L−1 NiNPs, in which the diameter increased up to 843 nm after 48 h. The concentration of Ni dissolved in the water increased with NP concentration and was similar for SON and NON-SON solutions. Our results indicate that sonication does not modify toxicity for the copepod A. tonsa. Mean EC50 values were similar for NON-SON (20.2 mg L−1) and SON experiments (22.14 mg L−1) in the acute test. Similarly, no differences occurred between the two different protocols in the semichronic test, with an EC50 of 7.45 mg L−1 and 6.97 mg L−1 for NON-SON and SON experiments, respectively. Acute and semichronic tests, conducted exposing A. tonsa embryos to NiCl2 concentrations from 0.025 to 0.63 mg L−1, showed EC50 of 0.164 and 0.039 mg L−1, respectively. Overall, A. tonsa is more sensitive to NiCl2 than NiNPs with EC50 being one order of magnitude higher for NiNPs. Finally, we exposed adult copepods for 4 days to NiCl2 and NiNPs (chronic exposure) to study the effect on fecundity in terms of daily egg production and naupliar viability. Egg production is not affected by either form of nickel, whereas egg viability is significantly reduced by 0.025 mg L−1 NiCl2 and by 8.5 mg L−1 NiNPs. At NiNP concentratio

Hippolyte inermis Leach 1814 is a benthic shrimp characterized by a peculiar mechanism of sex reversal influenced by diatom foods. In fact, the appearance of primary females in spring is due to an apoptotic early disruption of the androgenic gland and of the male gonad, triggered by still unknown compounds present in diatoms of the genus Cocconeis. The influence of diatoms on the reproductive ecology and life cycle of planktonic crustaceans has been demonstrated previously: some planktonic diatoms produce aldehydes inducing apoptosis in the embryos and in the larvae of marine copepods, reducing their viability. Both benthic and planktonic diatoms therefore produce compounds having an apoptotic effect on some tissues of target crustaceans, although the ecological significance of the two processes is different: deleterious for copepod populations, regulative for shrimps associated with Posidonia oceanica. In the present article we experimentally administered specific planktonic diatoms, their fractions and compounds known to induce apoptosis in planktonic copepods, to H. inermis postlarvae, to check whether the apoptotic effect is due to an identical family of diatom compounds, and to establish whether the processes observed in the plankton and in the benthos, respectively, are analogous or homologous, from an ecological point of view. Our results indicated that diatom compounds acting in the two systems are different, since both planktonic diatoms and their aldehydes had negligible effects on the sex ratios of cultured shrimps.