Case study on the Marine Biodiversity in the Falkland Islands: A review of kelpforest biodiversity with a eDNA data comparison

Abstract

Kelp forests are Marine ecosystems that support rich biodiversity and play an important role in coastal productivity worldwide. However, the health and resilience of Kelp forests in remote regions remain understudied. This study aims to establish a molecular baseline for a pristine kelp forest system in the Falklands, using environmental DNA (eDNA) to assess spatial and temporal patterns of marine life across the archipelago. Using high-throughput sequencing and multiple genetic markers, 730 operational taxonomic units (OTUs) were detected across 20 sites, of which 720 were identified at the phylum level. For this thesis, only the Kingdom and phylum levels were considered due to a lack of metabarcoding down to the species level. Analysis revealed clear spatial patterns in biodiversity, with higher species richness and evenness observed in East Falkland and Stanley South compared to West Falkland and New Island South. Fine-scale comparisons at Kidney Island and New Island demonstrated that pronounced ecological variation occurs even between closely spaced sites, influenced by environmental filtering and local habitat conditions. Temporal analyses from Stanley South showed increased diversity from February to July, particularly toward the mouth of Port William, highlighting the importance of seasonal dynamics in semi-enclosed systems. Taxonomic composition varied across sites, with Chromista dominates lower-diversity locations, and Animalia and Plantae are more prevalent in structurally complex habitats. These results provide a critical molecular baseline for future monitoring and conservation efforts, and establish the Falkland Islands as a globally relevant reference for remote temperate kelp forest ecosystems.