Things have been a little quiet around here over the holiday break, but that’s about to change in a big way. In just under a week’s time, I’ll be representing Georgia Aquarium in a new international consortium of scientists for an exciting expedition to explore the Abrolhos reef platform off the coast of Brazil from January 20-28. The Abrolhos are completely unique reefs: they’re the largest and southernmost in the South Atlantic and biologically very different from perhaps more familiar Pacific or Caribbean Reefs. You’d think they might show some similarity to Caribbean reefs, but not so, possibly because unfavourable currents and the influence of the Amazon pouring into the ocean between the two may serve as an important barrier to animal dispersal (more on that in future posts). There’s tremendously high endemicity there, which is to say that many of the resident critters are found nowhere else in the world. Of key importance is the main reef-forming coral Mussismilia braziliensis, a massive species that forms an unusual bommie-like reef structure called a mushroom reef; we’ll meet this species in more detail later too.
The main aim of the expedition is actually to go a bit deeper than the known parts of the Abrolhos, and look at the depths where light starts to get dim: the mesophotic zone. These parts of many reef platforms are poorly known and nowhere moreso than at Abrolhos, where these areas are completely unexplored. That’s because mesophotic reefs are beyond comfortable SCUBA diving range and therefore hard to get to. To study them between 300 and 3,000ft in depth, we’ll be using the Johnson Sea Link, a submersible that operates from the R/V Seward Johnson, which is on a 5 year assignment from it’s home at Harbor Branch Oceanographic Insitute to CEPEMAR, a Brazilian environmental services company.
There’s much more to come in future blog posts here and in my tweet stream @para_sight or using the hashtag #Abrolhos2011. We’ll discuss the Abrolhos reefs, mesophotic reefs, some geology and biology, as well as meeting the people and partners and exploring the logistic challenges of making a complex expedition like this happen. So, I encourage you to follow along and also to share this information with colleagues and (especially) students of marine science so that they might also follow and share in the excitement of discovering new parts of the ocean floor, never seen before, in tropical Brazil.