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The nativeAnguilla australis(shortfin eel) is a culturally significant species for indigenous Māori populations of New Zealand. At Lake Forsyth/Te Wairewa (Canterbury), local Māori have depended onA. australisas a source of mahinga kai (traditional food) for centuries. This lake experiences blooms ofNodularia spumigenaand the associated hepatotoxin nodularin has been detected in water samples. This study aimed to determine if nodularin accumulated inA. australis, and whether levels posed a health risk for human consumption. The maximum concentrations ofN. spumigenaand nodularin detected in lake water samples were 240 × 106cells/mL and 91,000 µg/L, respectively. Nodularin was detected in the liver and muscle of eels (max. 147 µg/kg in liver and 29 µg/kg in muscle). One muscle sample exceeded the recommended levels for safe human consumption of nodularin in fish (24 μg/kg). [ABSTRACT FROM PUBLISHER]

This work extends a previous report on the outbreak of an unknown neurotoxic sea slug along the southwestern Atlantic coast by providing identification to species level. In this study a c. 550 base pair (bp) region of the cytochrome c oxidase subunit 1 mitochondrial gene used for genetic barcoding was sequenced from three individual slugs sourced from three locations in Argentina. These data, in concert with previous description on the morphology and the presence of a neurotoxin of similar effect of that produced by pleurobranchs from New Zealand, confirm the identity of these sea slugs asPleurobranchaea maculata. This is the first record of the species in the Atlantic Ocean, thus suggesting an exotic origin. Given the fast spread of reports in the southwestern Atlantic (c. 2000 km of coastline in 6 years) we recommend urgent studies to determine the origin, toxicity, population genetics and impacts on local ecosystems. [ABSTRACT FROM PUBLISHER]

The Cawthron Institute Culture Collection of Micro-algae (CICCM) is a unique, nationally and internationally significant collection of 450 strains of approximately 100 micro-algae and 50 cyanobacteria species, both living and cryopreserved. The collection comprises 13 taxonomic classes and underpins research into the ecology and taxonomy of the isolates and the biotoxins they produce and their toxicity. The CICCM expanded significantly in the 1990s after a major harmful algae bloom event in the Hauraki Gulf, New Zealand. Since 2000, it has underpinned development of molecular detection tools and enabled development of new chemical testing methods for biotoxins in seafood. The tropical collection allows research into potential issues for New Zealand as the oceans warm, for example, the risks of ciguatera fish poisoning and palytoxins in seafood. Research results generated from isolates in the cyanobacterial collection have assisted national risk management regarding drinking water and informed the development of the New Zealand guidelines for managing cyanobacteria in recreational fresh waters. The actual living and cryopreserved micro-algae and cyanobacteria collection (without infrastructure) has a current estimated value of NZ$1.6 million. [ABSTRACT FROM AUTHOR]

Brown trout (Salmo trutta) are known to have effects on multiple trophic levels in New Zealand streams, but their impacts on lower trophic levels are less well understood within lentic systems. We examined the effects of brown trout removal using rotenone on zooplankton and phytoplankton community composition in the Upper Karori Reservoir, New Zealand. Significant shifts were observed in zooplankton and phytoplankton composition following removal of brown trout from the reservoir. Shifts in zooplankton community composition did not occur immediately following trout removal (February), but instead followed the likely timing of galaxiid spawning (July). The removal of brown trout likely resulted in reduced predation pressure on galaxiids. A major change occurred in the zooplankton community with the dominance shifting from larger crustaceans to smaller rotifers, indicating an increased predation pressure from the larval native galaxiid. A delayed response in zooplankton community composition change indicates rotenone was not the direct cause of this. A major shift in phytoplankton community composition occurred immediately following trout removal. This was not consistent with the trophic cascade hypothesis of reduced grazing pressure from larger zooplankton due to increased galaxiid predation as a result of brown trout removal. [ABSTRACT FROM PUBLISHER]

Lake Omapere, Northland, New Zealand, contributes significant inputs of freshwater to Hokianga Harbour, and is subject to toxic cyanobacterial blooms. During summer 2004, ADDA-ELISA analysis indicated microcystins were present in Pacific oysters (Crassostrea gigas) in Hokianga Harbour, leading to farm closures. Once the bloom had abated, continued detection of low microcystin levels suggested toxin production may be from cyanobacteria in the harbour not the lake. In this study, 20 cyanobacterial strains were isolated from Lake Omapere, its outflow and Hokianga Harbour. Morphological and molecular data identified diverse cyanobacterial species (15 Oscillatoriales and five Nostocales), including close relatives of toxin producers. Genes associated with toxin production were not detected in any strains and their cellular extracts were not toxic toArtemia salinalarvae. An in vitro feeding trial of Pacific oysters with a microcystin-producingMicrocystis aeruginosastrain (CAWBG16) was undertaken. No microcystins were detected in the shellfish using liquid chromatography-mass spectrometry. [ABSTRACT FROM AUTHOR]

Microcystisis a widely distributed genus of cyanobacteria that often forms surface blooms. The ability ofMicrocystiscolonies to regulate buoyancy in response to variations in nutrients and light, and in the presence of low rates of turbulent mixing, is well described. Here, we report on the movement of individual cells withinMicrocystis wesenbergiicolonies. Cells actively rearranged themselves within colonies, but randomly relative to other cells. Of the known types of cyanobacterial movement, gliding or twitching mediated by type IV pili was deemed the most likely causative mechanism. Transmission electron microscopy showed, however, no pilus-like structures onM. wesenbergiicell surfaces. We speculate that intra-colony movement may optimize colony fitness by helping individual cells to meet specific physiological requirements that may differ between the core and outer parts of the colony. This may increase fitness of cells and explain the recent dominance ofM. wesenbergiiin some New Zealand lakes. [ABSTRACT FROM AUTHOR]

Planktonic cyanotoxin poisoning events are well documented. More recently, benthic cyanobacteria have also been associated with bird, cattle and dog fatalities. Extensive mats of benthic cyanobacteria can contain high concentrations of toxins. This study investigated cyanotoxin production in cyanobacterial strains isolated from benthic freshwater mats dominated by cyanobacteria in Canterbury, New Zealand. Twenty-seven strains were isolated from ten water bodies and characterized using morphological and molecular phylogenetic characteristics. All strains were screened for genes involved in the biosynthesis of common cyanotoxins. Positive results were confirmed and cyanotoxin concentrations quantified using liquid chromatography–mass spectrometry. One chroococcalean, twenty oscillatorialean and six nostocalean strains were isolated into culture. All strains were cryopreserved and banked in the Cawthron Institute Culture Collection of Micro-algae. Genes associated with anatoxin-a biosynthesis were identified in ninePhormidiumstrains. Anatoxin-a was detected in all these strains, one of these strains also produced homoanatoxin-a. [ABSTRACT FROM AUTHOR]

The assessment of biological samples is critical for measuring the ‘health’ of New Zealand aquatic environments. Analysis of these samples commonly requires species identification and enumeration, which usually involves microscopy or microbiological methods. These techniques can be time-consuming, laborious, and are dependent on taxonomic expertise. Recent advances in molecular methods provide promising tools for assessing environmental samples. A range of molecular techniques are now used in New Zealand including: fluorescent in situ hybridisation; automated ribosomal intergenic spacer analysis; quantitative polymerase chain reaction; and, most recently, next-generation sequencing. The organisms (or targets) and environments monitored are equally diverse, ranging from cyanobacteria, rotifers and invasive fish in lakes, to macroinvertebrates, and biofilm communities in rivers, to bacteria, micro- and macro-algae and invertebrates in marine ecosystems. Despite research and validation demonstrating their potential, the application of these tools by monitoring agencies has been limited. Legislative requirements, costs, and a reluctance to change methodologies, are the most likely reasons for this. This review examines molecular tools that have been previously or are currently used for monitoring aquatic environments in New Zealand, and explores how these, and new techniques, may be applied in the future. [ABSTRACT FROM PUBLISHER]

Engagement and retention in treatment are important keys to adherence to highly active antiretroviral therapy (HAART) for people living with HIV/AIDS. Engaging with HIV-positive substance abusers is particularly challenging because of their multiple needs. Although co-locating primary care, substance abuse, mental health, and support services are thought to be most effective for treatment, such programs can be difficult to implement. Collaboration and linkage between community service providers offer a good alternative method for reaching service integration. This article overviews the treatment integration needs of HIV-positive substance abusers and describes how one empirically selected social service program originated and continues to assist a community-based approach to care. [ABSTRACT FROM AUTHOR]

Grounded theory was used to explore barriers to care and unmet needs for HIV-positive women caring for children under 18 years of age. The main study group consisted of 40 HIV-positive women caring for children. There were 21 Latinas, 11 Euro-Americans, 6 African Americans, and 2 participants from other ethnic groups. In addition, 5 providers of HIV services were interviewed to ensure trustworthiness of the data. The main findings identify and discuss needs for: (1) mental health and addiction services, (2) a better understanding of professional and paraprofessional roles, (3) improved privacy and confidentiality, (4) improved cultural sensitivity, and (5) other support service gaps are outlined and discussed in this study. [ABSTRACT FROM AUTHOR]