The Microbial Mats of Twin Cays

Microbial mats are laminated microbial ecosystems. They come in a variety of shapes and sizes and vary in thickness from a few millimeters to a few centimeters in thickness. Here are some examples of the types of microbial mats that are present on Twin Cays. The samples shown were collected in August and November 2000 and in June 2001.




Figures showing the different microbial mat morphologies and the different microbes in mats that we have observed on Twin Cays.

(A) Panels 1 and 2 show mats growing atop thin organic layers that overly peat. Panels 4 and 5 show thin mats growing directly on top of peat. Panels 3 and 6 show mats from the South Clear Cut and West Pond sites.


(B) Examples of the resident cyanobacteria in Twin Cays microbial mats: 1- Chroococcus sp.; 2- Microcoleus sp.; 3- Nodularia sp. (with opaque sheath); 4- Johannesbaptista sp.; 5- Aphanocapsa sp.; 6- Lyngbya sp. (thicker single filaments) and Microcoleus sp. (thin, multiple filaments within a sheath); 7- Johannesbaptista sp.; 8- Gloeocapsa sp.; and 9- Nodularia sp. (with clear sheath).