Diver in the Miskito Cays

MSEL, through the FORCE project, is providing support to the Centro de Estudios Marinos, an Honduran NGO which is untiringly working towards establishing an MPA in the Miskito Cays, east of Honduras. This project has a big heart. It’s not only about marine conservation, it’s about giving  a voice to the local communities, and giving them hope to ensure their marine resources and livelihoods.

Have a look at these inspirational short videos if you want to see more:

Honduras is blessed with a rich and abundant sea…

We are all reef guardians!

New MSEL paper published in Marine Ecology Progress Series by Rena, Manuel and Pete shows that for corals and macroalgae, size matters!

ABSTRACT: Corals and macroalgae compete for space, but the influence of species and size on the competitive outcome is poorly understood. Using a manipulative experiment, we evaluated the effect of macroalgal competition on the growth rate of corals with an emphasis on the colony size, species identity and the intensity of competition. Coral–macroalgal competition was studied among 3 Caribbean coral species (Porites astreoides, Agaricia agaricites and Colpophyllia natans) and 2 macroalgal species (Lobophora variegata and Halimeda opuntia) for 1 yr. Two coral colony sizes were used and, for the smaller size class, 2 levels of intensity for macroalgal competition (25 and 100% contact with the coral perimeter). Coral size had the greatest effect on competitive outcome; 2 species of large corals under competition grew as much as controls and a third species did not lose tissue. All small colonies lost between 18 and 22% of their original area after a year of competing with macroalgae, and the competitive outcome was insensitive to algal species. Coral colony size is a critical factor for the competitive outcome with algae and the intensity of contact between competitors is not important in smaller corals. In general, our results support the theory that algal blooms can inhibit coral population dynamics by causing a bottleneck in the survivorship of smaller size classes.

Karlo Hock was hosted by Dr. Scott Condie and The Southern Management Strategy Evaluation and Ecosystem Modelling group at CSIRO’s Marine and Atmospheric Research facilities in Hobart, Tasmania. Dr. Condie and his group have been developing high-resolution particle tracking models for the Great Barrier Reef ecoregion. Karlo will use the results of the particle-tracking models to construct reef-wide connectivity networks for the GBR system and study larval transport and resilience of coral reef metapopulations.

Some MSEL members and colleagues (Maggie, Catalina, K-le, and James) were recently lucky to have Professor Bob Steneck run a workshop for us at Heron Island on crustose coralline algae (CCA) identification. Workshop participants were first treated to an enlightening introductory seminar by Bob entitled: “You don’t know what you’ve got till it’s gone: the importance and fragility of crustose coralline algae.” This seminar was a great overview of everything we needed to know about CCA’s, and an amazing summary of Bob’s 40 years of experience and knowledge working on CCA’s. Topics in this seminar included: CCA geological history, evolutionary novelty, ecological and geological roles, and lessons from CCA’s as indicators of biological and climate change.

The next morning Bob gave us a seminar on CCA taxonomy and taught us about the current taxonomic schemes, morphological and field characters, anatomy, growth, reproduction, and taxonomic determinations. We then spent the day attempting to identify different CCA’s to species level using gross morphological characteristics, margin morphology, reproductive characteristics, vegetative characteristics, and trichocyte (hair) characteristics. It is important to be able to identify CCA’s to species-level, because of their role as habitat indicators, reef builders and inducing coral settlement. We all learnt a lot and had a great time, and are very grateful to Bob for sharing his knowledge and expertise with us.

Chris Doropoulos has joined Nancy Knowlton’s team at the Smithsonian’s Bocas del Toro research station, Panama, to assist with the annual spawning event of the Montastrea annularis complex. Nancy Knowlton and Don Levitan have been recording the spawning times of around 500 marked colonies of M. annularis, M. faveolatus, and M. franksii, for approximately 18 years – very impressive stuff! Over the years they have unravelled how precise spawning is achieved by a combination of external cues, genetic precision, and conspecific signalling. Last night (7/09/2012) the major event occurred, filling the water with millions of eggs, sperm, and gorging fish and invertebrates: a truly amazing event to take part in.

Montastraea annularis | Montastraea franskii | Montastraea faveolata

Diadema sea urchin

Alyssa’s first PhD paper has been published online in Coral Reefs. In this study, we used aquaria trials to investigate for the first time the grazing impact of the abundant and common surgeonfish, Acanthurus nigrofuscus and Ctenochaetus striatus, on epilithic algal turfs. Both species overwhelmingly preferred to graze on sparse/short algal turfs over dense/long algal turfs. C. striatus is classified as a detritivore, that prior to our study was thought to ‘brush’ detritus from the surface of the epilithic algal matrix, causing little damage to algal strands. Surprisingly, we found that C. striatus removed significantly more algal turf per hour than the grazer, A. nigrofuscus. The capability of C . striatus to remove algal turfs through their foraging activity implies that this species may substantially affect algal turf dynamics on coral reefs, as they are one of the most common and  abundant spcies throughout the Indo-Pacific.
              Grazer                           Detritivore

 Marshell A and Mumby PJ (2012) Revisiting the functional roles of the    surgeonfish Acanthurus nigrofuscus and Ctenochaetus striatus. Coral Reefs. In Press. http://www.springerlink.com/content/62n464287461wt35/

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Abstract:

The great sensitivity of coral reefs to climate change has raised concern over their resilience. An emerging body of resilience theory stems largely from research carried out in a single biogeographic region; the Caribbean. Such geographic bias raises the question of transferability of concepts among regions. In this article, we identify factors that might predispose the Caribbean to its low resilience, including faster rates of macroalgal growth, higher rates of algal recruitment, basin-wide iron-enrichment of algal growth from aeolian dust, a lack of acroporid corals, lower herbivore biomass and missing groups of herbivores. Although mechanisms of resilience are likely to be ubiquitous, our analysis suggests that Indo-Pacific reefs would have to be heavily degraded to exhibit bistability or undergo coral–macroalgal phase shifts.

(http://www.sciencedirect.com/science/article/pii/S016953471200095X)

It’s a matter of life or depth… Introducing Marine Man! A new comic by a friend of Pete and MSEL, Ian Churchill is due to be released in comic book stores worldwide shortly. Issue one features a a focus on a real life marine biologist – Peter J Mumby: