Thesis updates: Kate and Julia
Last week we bid a fond farewell to Xiaodong as he heads back to China. We loved getting to know you over the past year, you brought an incredible energy and thoughtful discussion to our lab group (not to mention unparalleled culinary skills). Playing badminton after lab meetings will never be the same without you. We wish you all the best and safe travels, and we hope you will drop by the lab the next time you’re in St. John’s!
Also last week Julia and Kate presented their thesis updates to the lab group!
Julia is working on modelling the distribution of phytobenthic species – photosynthetic flora such as kelp or microscopic diatoms that live on the seafloor – and primary herbivore assemblages. In Julia’s talk “Predicting the distribution of key algal species and dominant invertebrate assemblages in Placentia Bay, Newfoundland and Labrador” we learned about the dominant macrophytes of the North Atlantic, Laminaria saccharina and Agarum clathratum, and their important role in bolstering biodiversity as habitat-forming structures and providing numerous ecosystem functions. Agarum clathratum may be resistant to decimation by sea urchins that plague other kelp forests globally, and so may act as refuge for fishes and invertebrates when other kelps disappear! After a successful field season of acoustic surveys and ground-truthing, Julia has been building habitat maps using random forest clustering, and species distribution models for Agarum clathratum, coralline algae, green sea urchins, and diatom mats (microphytobenthos) to understand the characteristics that drive herbivore-macrophyte-microphyte distribution in these important species.
Kate’s research aims to assess the influence of abiotic characteristics on the habitat selection of benthic organisms and monitor how these factors change seasonally. In Kate’s talk “Seasonal change in factors influencing benthos habitat selection in Conception Bay, Newfoundland” she taught us about the economically and ecologically important crustaceans of Newfoundland and how she is working to improve traditional habitat mapping.
Ocean conditions change seasonally – especially in sub-Arctic regions like Newfoundland and Labrador where there is seasonal ice cover - and so do species distribution and community assemblages. However, most species distribution maps and habitat maps that are used to inform management decisions are only built off of one sampling event, which can miss important temporal variation in seafloor communities. Kate is using a four season replication of ground-truthing in the Holyrood arm of Conception Bay to build habitat maps and compare community assemblages and environmental conditions across seasons. Kate’s research demonstrates how much a habitat map can vary over a short period of time and highlights the need to consider temporal variation when building maps that will influence management and conservation decisions.
Next week we will hear from Aaron and learn all about mapping eelgrass using drones!