Hi, Patrick Nichols! Great to have you on ReefBites.
Patrick is currently a PhD student at the University of Hawaiʻi at Mānoa, studying coral reef molecular ecology, environmental DNA, climate change, and invasive species. Learn more about Patrick’s research below:
Give an elevator pitch of what your research/project is about.
Coral reefs support the most diverse assemblages of marine life on Earth, yet are declining due to local and global stressors. Rapid and widespread monitoring is essential for tracking ecosystem responses, but assessment of coral communities traditionally relies on time-consuming visual estimates of coral cover, the percentage of substrate occupied by living corals. The analysis of environmental DNA (eDNA), free DNA from filtered seawater, offers fast and efficient insights into the abundance and distribution of species, yet it remains untested to monitor coral biomass. In our recent paper, we demonstrate that visual estimates are highly correlated with the abundance of coral eDNA on reefs in Hawai’i measured with a relatively simple, rapid, but replicated PCR-based metabarcoding approach. Careful primer selection and target sequence lengths play an important role in determination of coral abundance from eDNA biomass. Given its broad applicability and ease of use, eDNA metabarcoding can provide complementary analytical support for biomonitoring programs and management initiatives tracking changes in coral cover caused by climate change and other disturbances on coral reefs.
Why is this research/project important and timely?
With local and global stressors threatening the biodiversity of coral reefs, it is imperative that we increase monitoring efforts in order to establish baseline metrics, but also to ensure effective management. The decline of coral reefs across the globe has gained traction in recent years, but traditional monitoring efforts are highly resource-intensive (costing thousands of dollars and requiring teams of scientists or divers for a single site). Environmental DNA surveying of coral reefs is a cost-effective method (simply using bottles of seawater) to monitor coral reefs, especially in areas that are logistically challenging to access. Establishing regular surveys in impacted areas is crucial, especially as shifting baselines continue to occur due to climate change.
What is the broader impact and implication of your findings?
eDNA surveys of coral reefs are promising not only for establishing baseline diversity and abundance metrics, but also for biomonitoring of invasive species. The high sensitivity and relatively low cost of eDNA sampling allows for detection of multiple species of interest, which in the case of invasive species, can help track their spread, or help inform managers about failed removal efforts. eDNA surveys can detect species that would otherwise be missed by traditional surveys, and therefore, when used in conjunction with traditional methods, can increase the scope and depth of existing monitoring efforts.
How did you come to work in this field/project?
My background and training in invasive species led me to existing literature where eDNA surveying was being used to rapidly monitor the spread of invasive fish into the Great Lakes. This gave me an idea to pursue using a similar method to track changes to coral reef ecosystems. Currently, eDNA has been used to survey everything from microbe diversity in soils to ancient DNA from ice, but no one had developed this tool for assessing the diversity and abundance of corals on reefs. So I decided to make it the focus of my Master’s thesis to develop eDNA as a tool specifically for coral reefs as well.