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Biology subjects

Harrison, P. L.

Publications and source records attributed to Harrison, P. L..

4 recordsLinked to original sources

Larval seedboxes: a modular and effective tool for scaling coral reef restoration

Natural recovery of degraded coral reefs is constrained by low larval recruitment, limiting restoration at ecologically meaningful scales. While propagule-based approaches have proven effective in plant-dominated systems, scaling larval restoration for sessile invertebrates like corals remains challenging. Traditional coral larval methods rely on net enclosures, restricting impact to small areas (<75 m2). We developed and tested a modular, passive larval delivery system - the larval seedbox - to overcome these spatial constraints. Each unit (600 x 500 x 300 mm; 11 kg) enables delayed release of competent larvae near the benthos, enhancing substrate encounter rates over broader areas. At Lizard Island (Great Barrier Reef), five seedboxes delivered [~]14 million larvae across [~]2 ha of degraded reef. Larval release coincided with slack currents to facilitate local retention and subsequent dispersal. Settlement was assessed on 234 tiles placed in concentric arrays around each seedbox. After 48 hours, 85% of tiles had settlers (up to 1,041 per tile), with mean densities 24-times greater than background levels. Enhanced settlement was directly quantified across >470 m2, with spatial modelling estimating >3,000 m2 via tidally driven dispersal. The larval seedbox enables unrestrained, scalable coral larval seeding and represents a practical advance toward broad-scale reef restoration.

ecology↗

Microbiome stability is linked to coral thermotolerance

Corals associate with a diverse community of prokaryotic symbionts that provide nutrition, antioxidants, and other protective compounds to their host. However, the influence of microbes on coral thermotolerance remains understudied. Here, we examined the prokaryotic microbial communities associated with colonies of Acropora cf. tenuis that exhibit high or low thermotolerance upon exposure to 33{degrees}C (heated) relative to 29{degrees}C (control). Using 16S rRNA sequencing, we show that the microbial community structure of all A. cf. tenuis colonies were similar at control temperature. Thermotolerant colonies, however, had relatively greater abundance of Endozoicomonas, Arcobacter, Bifidobacterium and Lactobacillus. At elevated temperature, only thermosensitive colonies showed a distinct shift in their microbiome, with an increase in Flavobacteriales, Rhodobacteraceae, and Vibrio, accompanying a marked bleaching response. Functional prediction indicated that prokaryotic communities associated with thermotolerant corals were enriched for genes related to metabolism, while microbiomes of thermosensitive colonies were enriched for cell motility and antibiotic compound synthesis. These differences may contribute to the variable performance of thermotolerant and thermosensitive corals under thermal stress. Identification of microbial taxa correlated with thermotolerance provides insights into beneficial bacterial groups that could be used for microbiome engineering to support reef health in a changing climate.

microbiology↗

Nanodelivery of lipids to coral larvae maximises post-settlement survival: Implications for larval ecology and reef restoration.

Interest in reef restoration is increasing as coral mortality has accelerated at an unprecedented rate. However, high mortality rates of coral early-life stages represent a population bottleneck, which directly impacts the effectiveness of restoration projects. While most coral larvae are considered lecithotrophic and catabolise maternally transmitted lipids to meet metabolic demands; here we demonstrate that coral larvae can be facultative feeders. We used nanoparticles to deliver triacylglycerides to aposymbiotic larvae which resulted in a 30% increase in larval energetic lipids, and a 46% increase in survival rate, up to 16 weeks post-settlement. Changes in phospholipid molecular species in the larvae suggest phagocytosis of the nanoparticles, and an increase in free fatty acids indicates lipolysis of the phagocytosed triacylglycerides. We suggest that a continuum of nutritional strategies should be recognised in coral early-life stages, and that nanoparticles can be used by restoration practitioners to deliver nutritional resources to maximise restoration outcomes.

ecology↗

PGP-UK: a research and citizen science hybrid project in support of personalized medicine

Molecular analyses such as whole-genome sequencing have become routine and are expected to be transformational for future healthcare and lifestyle decisions. Population-wide implementation of such analyses is, however, not without challenges, and multiple studies are ongoing to identify what these are and explore how they can be addressed. Defined as a research project, the Personal Genome Project UK (PGP-UK) is part of the global PGP network and focuses on open data sharing and citizen science to advance and accelerate personalized genomics and medicine. Here we report our findings on using an open consent recruitment protocol, active participant involvement, open access release of personal genome, methylome and transcriptome data and associated analyses, including 47 new variants predicted to affect gene function and innovative reports based on the analysis of genetic and epigenetic variants. For this pilot study, we recruited ten participants willing to actively engage as citizen scientists with the project. In addition, we introduce Genome Donation as a novel mechanism for openly sharing previously restricted data and discuss the first three donations received. Lastly, we present GenoME, a free, open-source educational app suitable for the lay public to allow exploration of personal genomes. Our findings demonstrate that citizen science-based approaches like PGP-UK have an important role to play in the public awareness, acceptance and implementation of genomics and personalized medicine.

genomics↗