BREAM, as part of the Bermuda Biodiversity Project at BZS, has developed the most comprehensive maps of Bermuda's coral reefs and other marine habitats that exist. In this post we will describe how we mapped all of the 35,000 patch reefs in the North Lagoon of Bermuda.
Our goal was to create a Geographic Information System (GIS) of all the reefs found around Bermuda. A GIS is a computerized map that also contains information about each object mapped. Computerized maps are better than paper maps because once you put all the information you know into the program, you can then ask it to tell you new information which the program can calculate based on what you told it. Some questions you can ask a computerized mapping programme are listed at the bottom of this post.
Before we mapped the location of each reef into a GIS (also called a geo-referenced map database), we needed a set of images of the entire Bermuda reef platform. The BBP, with assistance from the Dept. of Conservation Ser…
By Brittany Huntington, Doctoral Student, RMSAS Univ. of Miami and BREAM summer graduate intern, funded by ACP
What are these? Fossilized marshmallows? White chocolate petite fours? No no…this is real science people!
This abundance of ice cube shaped trapezoids are nicknamed “clod cards”: a simple yet effective way to measure water movement as a proxy for current and flow exposure at underwater sites (developed by Doty et al., 1971).
The mechanism is straight-forward. These plaster of paris ‘clods’ are all identical in composition, shape and size. Each clod should therefore dissolve slowly underwater at a constant rate.
By weighing the dry clod cards before deployment, leaving them underwater for a fixed time period (usually between 24-48 hours) and then collecting them and re-weighing each clod, we can determine the precise weight of plaster of paris lost from each card. Clods losing more weight were exposed to greater water flow than cards exposed to less water flow.
Here is a google map of all the Open Wrecks in Bermuda, as posted by the Bermuda Government Department of Environment and Natural Resources. I fixed a couple of location errors. Use at your own risk, of course.