Photo Credit: NOAA Florida Keys National Marine Sanctuary

By: Katie Wood & Kayla Ripple

From mangroves to seagrass beds to coral reefs, tropical marine ecosystems are incredibly diverse and very important to support our life on land. There is much we can learn from the connections between habitats, but also vital concepts that can be shared about ecology and what this means for other similar habitats.

1. Connectivity: Seagrass beds and coral reefs are highly connected ecosystems that vary in habitat type. Seagrass beds are just what you would expect- grassy areas in the ocean, full of small and large invertebrates, fishes, and many types of seagrasses. Coral reefs are similar in that they too are full of small and large invertebrates, fishes, and many types of corals. Seagrasses are found in sandy bottom areas while coral reefs are typically in hard bottom areas, allowing each ecosystem to fill a “niche” in habitat role. Some species of fish are born in seagrass beds and live as adults on the reef, while other species of fish are born on the reefs and live as adults in seagrass beds. Some fishes simply move back and forth between the two habitats, bringing with them nutrients from each ecosystem (yes, these nutrients are in the form of poop…). This connectivity has important implications for fish stocks of both reef and seagrass bed environments.

untitled3

Photo Credit: Kayla Ripple, White Bank Reef, Key Largo, FL

2. Diversity: Seagrass beds and coral reefs are highly diverse ecosystems, both in the species that reside in them (species diversity) and in the genetic makeup of individuals that represent various species (genetic diversity). A study by Hughes and Stachowicz proves the importance of genetic diversity in an eel grass bed. In the study, patches of eelgrass were planted in varying genotypic diversities in plots along Bodega Bay. The study progressed over five months, until a flock of Brant Geese decimated the scientists sample plots by eating large amount of the seagrass. The intense herbivory, that could have ultimately destroyed the sample plots, yielded some interesting results. Plots where the scientists had planted more genotypes of eel grass (higher genetic diversity) recovered at faster rates than those with less genotypic diversity.

At Coral Restoration Foundation, we strive to outplant corals at high genetic diversity levels for these very reasons- if a storm or catastrophic event were to occur, like a massive coral bleaching or disease event, the chance of recovery may be enhanced by the great genetic diversity we outplant.

untitled2

Photo Credit: Kayla Ripple, White Bank Reef, Key Largo, FL

3. Resilience: The diversity of a population and ecosystem, translates to its ability to resist different stressors like detailed above. The ability of a population to recover after a stressful event is an important concept in restoration and recovery efforts. In the case of the eelgrass beds, more diverse plots recovered at a greater rate- they were more “resilient” to the stress of herbivory from the Brant Geese. Similarly, a more diverse coral restoration site may prove to be more resilient to various environmental changes overtime.

 

 

Resources:

Hughes, A. & Stachowicz, J. (2004). Genetic diversity enhances the resistance of a seagrass ecosystem to disturbance. Proceedings Of The National Academy Of Sciences, 101(24), 8998-9002.