A5011466414- Environmental DNA in Biodiversity Studies
- Microbial Community Ecology and Physiology
- Protist diversity and phylogeny
- Fish Ecology and Management Studies
- Reproductive biology and impacts on aquatic species
- Aquatic Ecosystems and Phytoplankton Dynamics
- Identification and Quantification in Food
- Isotope Analysis in Ecology
- Sperm and Testicular Function
- Soil and Water Nutrient Dynamics
- Aquaculture Nutrition and Growth
- Marine and coastal ecosystems
- Water Quality and Pollution Assessment
- Genetic and Clinical Aspects of Sex Determination and Chromosomal Abnormalities
- Biocrusts and Microbial Ecology
- Wastewater Treatment and Nitrogen Removal
- Freshwater macroinvertebrate diversity and ecology
- Ecology and biodiversity studies
- Marine Bivalve and Aquaculture Studies
- Animal Behavior and Reproduction
- Gut microbiota and health
- Geology and Paleoclimatology Research
- Diatoms and Algae Research
Cawthron Institute
2019-2025
Victoria University of Wellington
2023-2024
University of Otago
2017-2024
University of Auckland
2021
Norwegian Institute of Marine Research
2021
Microbial biodiversity monitoring through the analysis of DNA extracted from environmental samples is increasingly popular because it perceived as being rapid, cost-effective, and flexible concerning sample types studied. can be diverse media before high-throughput sequencing prokaryotic 16S rRNA gene used to characterize taxonomic diversity composition (known metabarcoding). While sources bias in metabarcoding methodologies are widely acknowledged, previous studies have focused mainly on...
Abstract Analyses of sedimentary DNA ( sed DNA) have increased exponentially over the last decade and hold great potential to study effects anthropogenic stressors on lake biota time. Herein, we synthesise literature that has applied a approach track historical changes in biodiversity response impacts, with an emphasis past c. 200 years. We identified following research themes are particular relevance: (1) eutrophication climate change as key drivers limnetic communities; (2) increasing...
Marine sediments contain a high diversity of micro- and macro-organisms which are important in the functioning biogeochemical cycles. Traditionally, anthropogenic perturbation has been investigated by identifying macro-organism responses along gradients. Environmental DNA (eDNA) analyses have recently advocated as rapid cost-effective approach to measuring ecological impacts efforts underway incorporate eDNA tools into monitoring. Before these methods can replace or complement existing...
ABSTRACT Lake surface sediments are dominated by microorganisms that play significant roles in biogeochemical cycling within lakes. There is limited knowledge on the relative importance of local environmental factors and altitude bacterial microeukaryotic community richness composition lake sediments. In present study, sediment samples were collected from 40 lakes along an gradient (2–1215 m). Microbial communities characterized using 16S (bacteria) 18S (microeukaryotes) rRNA gene...
Lake sediments are natural archives that accumulate information on biological communities and their surrounding catchments. Paleolimnology has traditionally focussed identifying fossilized organisms to reconstruct past environments. In the last decade, application of molecular methodologies increased in paleolimnological studies, but further research investigating factors such as sample heterogeneity DNA degradation required. present study we investigated bacterial community (16S rRNA...
Abstract Monitoring fish is necessary for understanding population dynamics, tracking distribution patterns and evaluating conservation efforts. Molecular techniques targeting environmental DNA (eDNA) are now considered effective methods detecting specific species or characterising communities. The analysis of from lake‐surface sediments (sedDNA) can provide a time‐integrated sampling approach which reduces the variability sometimes observed in water samples. However, studies sedDNA have had...
Bacteria are vital components of lake systems, driving a variety biogeochemical cycles and ecosystem services. Bacterial communities have been shown to skewed distribution with few abundant species large number rare species. The contribution environmental processes or geographic distance in structuring these is uncertain. discrete nature lakes provides an ideal test case investigate microbial biogeographical patterns. In the present study, we used 16S rRNA gene metabarcoding examine patterns...
Non-native fish have been shown to deleterious impacts on freshwater ecosystems in New Zealand. Early detection is critical for their effective management. Traditional capture-based techniques may not detect newly introduced fish, especially if they are present low abundance. Molecular that target environmental DNA (eDNA) shown, many instances, be more sensitive, cost-effective and require lower sampling effort. However, appropriate strategies needed ensure robust interpretable data...
Abstract Environmental DNA provides an opportunity to track long‐term changes in biological communities lake ecosystems but the detection of macroorganisms, such as freshwater fish and mussels, sedimentary (sedDNA) has only been successfully reported a few studies date. Factors low abundance target organisms, sampling location, molecular approach used, quantity may influence detection, though exploring these factors are lacking. In present study, sediment cores were collected from depocenter...
Anthropogenic eutrophication is one of the most pressing issues facing lakes globally. Our ability to manage lake hampered by limited spatial and temporal extents monitoring records, stemming from time-consuming expensive nature physiochemical biological monitoring. Diatom-based biomonitoring presents an alternative traditional monitoring, yet it restricted high degree taxonomic expertise required. Environmental DNA metabarcoding, while providing a promising substitute for diatom community...
Estradiol-17β (E2) and 11-ketotestosterone (11KT) have been implicated in vitellogenesis regulating expression of the follicle-stimulating hormone receptor (fshr), respectively. To override captivity-induced reproductive block shortfinned eel, Anguilla australis, we hypothesized that combination, 11KT E2 would stimulate ovarian uptake vitellogenin (Vtg). Early pubertal eels received implants containing varying concentrations (0, 0.2, 2, 5 mg) with or without (1 mg). Vtg levels were...
Abstract Biological communities within lake surface sediments play a vital role in biogeochemical cycling and ecosystem services. Knowledge on abundance‐occupancy patterns assembly processes across large spatial scales over multiple environmental gradients is limited, yet essential to aid protection restoration. In the present study, sediment samples were collected from 296 lakes wide scale covering interacting including size, depth, altitude, trophic state. A suite of physicochemical...
Benthic proliferations of Microcoleus autumnalis (basionym Phormidium autumnale) and closely related taxa are being reported with increasing frequency in streams rivers worldwide. This species commonly produces the potent neurotoxin anatoxin, exposure to this has resulted animal fatalities human health concerns. Bacterial communities within cyanobacterial assemblages can facilitate processes such as nutrient cycling posited influence growth function. However, there is limited knowledge on...
Our previous work documented significant advancements in steroid-induced progression of oogenesis, demonstrating that co-treatment female eels with 11-ketotestosterone (11KT) and estradiol-17β (E2) successfully induced uptake vitellogenin by oocytes. Here we evaluate the effects this steroid on subsequent time to ovulation egg quality shortfinned artificially matured hypophysation. Co-treatment 11KT (1 mg) E2 (0.2 or 2 significantly reduced therefore, amount pituitary homogenate required,...
Lakes provide habitat for a diverse array of species and offer wide range ecosystem services humanity. However, they are highly vulnerable as not only impacted by adverse actions directly affecting them, but also those on the surrounding environment. Improving knowledge processes responsible community assembly in different biotic components will aid protection restoration lakes. Studies to date suggested combination deterministic (where biotic/abiotic factors act fitness differences amongst...
ABSTRACT Freshwater fish are in a perilous state with more than 30% of species considered critically endangered. Yet significant ecological and methodological complexities constrain our ability to determine how disturbances impacting native communities. We review current methods used assess the responses communities, especially fish, disturbances, focus on lakes. These include contemporary population surveys, manipulative experimental approaches, paleolimnological approaches Indigenous...
AbstractPressures on lakes in Aotearoa New Zealand are increasing due to elevated catchment nutrient loads, establishment of non-native species, and climate change. Current government legislation requires that pressures managed avoid eutrophication degradation lake health. This approach information the state at regional national scales, which is challenging as less than 5% currently monitored. In this study, we (1) modelled trophic status a scale using highly representative dataset...