Dr Harry Layfield1, Prof Martin Genner1
1University Of Bristol, Bristol, United Kingdom
Biography:
Harry is a molecular ecologist who primarily uses genomic tools to address key ecological and evolutionary questions concerning invertebrates. His research focuses on the diversity and speciation of invertebrates in freshwater ecosystems, employing techniques such as environmental DNA metabarcoding and whole-genome sequencing
Abstract:
A decline in freshwater ponds in the UK over the past century has prompted an increase in artificial ponds to enhance biodiversity restoration. To determine the biodiversity value of these ponds, it is crucial to understand how invertebrate community structure changes spatially and temporally. Traditional invertebrate survey techniques, often reliant on net surveys, can be time-intensive particularly for generating long-term data and may overlook juveniles and cryptic species. Environmental DNA-based surveys present a potential solution.
We studied the temporal and spatial variation in invertebrate communities in the UK, using environmental DNA (CO1) metabarcoding samples collected over 25-months from new and mature ponds, and proximate streams. In total, amplicon sequence variants were assigned to 273 species of invertebrates, but the majority of reads were assigned to Eurotatoria (rotifers; 61%) and Hexanauplia (copepods;12%). However, clear differences between the sampled habitats were revealed and seasonality was observed in community structure, which was most prominent in mature ponds and least evident in streams.
The results highlight the potential for eDNA metabarcoding to resolve the spatial and temporal structuring of freshwater invertebrate assemblages. However, the efficacy of CO1 metabarcoding is not yet optimal. Primer specificity is an important consideration when implementing eDNA based surveys, as only ~1% of all raw reads generated were assigned to an invertebrate taxon. Characterisation of new more highly specific markers for the invertebrate groups is needed. With improved primer specific developments, eDNA metabarcoding has the potential to play an important in future freshwater invertebrate surveys and conservation.