Where in the world is the parrotfish project team? This summer, master's student Hannah Rempel and undergraduate research assistants Emma Barton and Peter Vanderbloomer are studying the impacts of parrotfish grazing on coral communities on Bonaire, Dutch Caribbean. This work is part of a broader study comparing patterns and impacts of parrotfish grazing across multiple parts of the Caribbean.
The focus of Hannah's thesis and the team's work this summer is to:
(1) track the healing of an endangered, frequently targeted coral species from parrotfish grazing scars, and (2) compare how the intensity of parrotfish predation on corals varies on islands with high coral cover (e.g. Bonaire) compared to ones with comparatively low coral cover (e.g. St. Croix).
What have they been up to?
So far, they have mapped and monitored >100 coral colonies with >250 parrotfish grazing scars! They photograph these individual scars every few days, and using imaging software they can calculate changes in scar size over time– allowing us to determine how much scar tissue heals and what factors about the scars, corals and sites influence recovery rates.
In addition, the team is also documenting using image analysis of quadrats of the reef bottom to determine the percent cover of different coral species, types of algae and other food types commonly targeted by parrotfishes, 'stalking' parrotfish to record their grazing behavior, surveying the biomass of fish, and determining the abundance of parrotfish grazing scars across different coral species.
When they are not underwater, the team has been working to involve the local community in their work and share their research. Hannah is working with the largest dive shop on the island, Dive Friends Bonaire to start a citizen science program tracking the populations of the largest three Caribbean parrotfish species since their populations are decreasing throughout the Caribbean. In addition, she is giving talks on her research both in English and Dutch Caribbean creole (which she learned when she worked as a biologist for the Bonaire National Parks Foundation prior to joining our lab).
It is time for the team to get back underwater and get more data! We look forward to sharing the results of our work with you all in the future.
Thanks for your interest in our field work! Masha danki, muchisima gracias, dank u wel!