March 2023 | By Leah Harper

Leah Harper is MarineGEO’s Central Technician. She planned and led the 2022 Carrie Bow Cay Field Campaign.

What happened to coral reefs while humanity battled the COVID-19 pandemic over recent years? To find out, ten MarineGEO researchers revisited the Carrie Bow Cay station on the Belize Barrier Reef in late 2022. Unfortunately, we found that corals are battling their own pandemic.

The expedition followed a two-year hiatus due to the COVID-19 pandemic, and focused on surveying marine life, continuing ongoing research, and testing new field methods. One of our key tools this field season is Reef Life Survey, a standardized method for surveying trends in reef fishes and corals developed by a non-profit citizen science program. Using such standardized approaches to survey fish and invertebrates is a core component of MarineGEO's research across the network. At Carrie Bow, we have used Reef Life Survey to track biodiversity in forereef, patch reef, mangrove, seagrass, and sand habitats since 2015. The resulting data confirm that different marine habitats in the seascape harbor distinct fish communities (Harper et al. 2022). For this trip, the MarineGEO team scaled up survey efforts dramatically. We completed a total of 42 surveys at 21 sites. By adding six new sites and many new surveys, we expect better ability to discern how the spatial arrangement of the seascape shapes marine animal communities. 

A key focus of MarineGEO work at Carrie Bow Cay involves the corals that build the ecosystem. Across 240 m2 on eight coral reef sites, we identified coral species and tracked signs of stony coral tissue loss disease (SCTLD). SCTLD has been afflicting corals up and down the Mesoamerican Barrier Reef and throughout most of the Caribbean for the last 4 years. We also took tissue samples from 90 tagged coral colonies as part of ongoing SCTLD fate tracking research begun in 2019.  Of those corals, roughly one third have perished since the start of our study, along with a decline in coral cover on MarineGEO study sites from approximately 13% to 10%.