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Medalla Light joins our coral reef restoration effort

Our new project with the most iconic beer company in Puerto Rico is underway!

The Story

A little over a year ago, we were sitting around enjoying a nice cold brewsky after a long day in field with our colleagues HJR Reefscaping, when Evan was hit by a spark of creativity. We had just learned about this bottle crushing machine from New Zealand that turns glass bottles into sand, so it was already at the forefront of our minds when Evan mentioned

"Hey, let's see if we can crush glass beer bottles and use that sand in our cement mixture for coral reef restoration".

And the heavens opened, light shone down on us and the wheels started turning in our minds as we drafted our grant proposal to make this a reality.


This recycled glass sand (RGS) was already being put to use in other innovative ways, like filling sandbags for hurricane prep in the US Virgins Islands and being used in construction projects elsewhere in the world. We figured our idea would be a great way to address a very important and critical issue for our island - reducing our glass waste. Since we do not recycle glass in Puerto Rico, it just accumulates in our landfills and ends up on our reefs as trash. We really need a lasting solution to this problem!

But before we could move along with our idea, we first needed to do our research. We needed to know:

  1. What are the true components of the recycled glass sand when the bottles are crushed? Answer: primarily silica, with some calcium carbonate and other natural minerals that are found in sand

  2. What bottles can we use so that those components match the closest to the minerals we have in the Caribbean? Answer: those that are manufactured in the Caribbean using Caribbean sand

Of course, there was a lot more research that went into this to confirm that the RGS would not cause any harm or endanger any corals that we were planting. But the most important part was to find bottles that we could confirm were made in the Caribbean, and not imported from other parts of the world. So we reached out to our local brew, Medalla Light, and here is where our story takes off...


Medalla Light gets involved

So we reached out to Medalla Light to inquire about where their bottles were made. Turns out, they are manufactured in the Mexican Caribbean ( same region, #2 on our list checked off!) and after speaking with the bottle manufacturer themselves, we learned that the glass is composed of silica (#1 checked off the list!). During this discussion, Medalla Light became really intrigued by our project and wanted to know more. So, we presented them with the idea and what we would need to get started. They were on board instantly!

So, what are we doing exactly??

Medalla Light provided us with the funds we needed to purchase the bottle crushing machine and acquire the restoration supplies to test our pilot project. Our project will be using three different mixtures of cement/marmolina/RGS, with the goal being that the greatest ratio of RGS to the other materials will still serve the same purpose as the traditional cement/marmolina mixture. In other words, we want to see how much RGS we can introduce to the mix without sacrificing the integrity of the mixture and its ability to secure the corals to the seafloor.

Crushing the glass bottles is a very easy process with the bottle crushing machine. Essentially, we insert a bottle neck down into the top of the machine and wait a few seconds for it to be pulverized into sand which collects in a 5-gallon bucket underneath. It makes for a really nice afternoon of work to turn beer bottles into sand. #science

a coral fragment is planted to the reef
A coral fragment is planted to the reef using our cement/marmolina/RGS mixture

Next, we configure our ratios of cement/marmolina/RGS and prepare the dry mixtures in a 5-gallon bucket that we will take to the field. Once at the restoration site, we introduce seawater to the bucket and mix it up until it forms a nice cement paste that is ready to be taken underwater (yes, cement hardens underwater!). We then use that cement to secure small fragments of coral to the reef. In this case, we are using the Caribbean's iconic Elkhorn coral - an endangered species that is responsible for building most of the three dimensional reef structure in our region.

Our colleagues HJR Reefscaping have been maintaining an elkhorn coral nursery (where these small corals are grown for the purpose of replanting) in the Guayanilla region, thanks to years of support from local energy provider EcoElectrica.

HJR Reefscaping founder Hector Ruiz clips a fragment of coral from the parent colony
HJR Reefscaping founder Hector Ruiz clips a fragment of coral from the parent colony
A coral nursery of elkhorn corals in Guayanilla, maintained by HJR Reefscaping
A coral nursery of elkhorn corals in Guayanilla, maintained by HJR Reefscaping

After we have planted our coral fragments using the experimental mixture (aimed to be completed by the end of this summer!), we will then play the waiting game with Mother Nature. Corals grow very slowly - but elkhorn coral grows rather fast compared to others! - so we will be monitoring their growth over a one-year period. During this time, we will visit the outplanting site and take measurements and photos of the corals to monitor their progress. We are hoping to see that the corals grow over the cement with no problems, just like they do with our traditional cement/marmolina mixture.


Medalla Light opens new doors for ocean conservation

This project is the first time that Isla Mar has worked with a business as sponsor to a scientific project, rather than our traditional outlets like competitive scientific grants from the federal goverment (see our Projects page to learn more about our research). It has been a pleasure to work with their team, as their excitement about this effort only strengthens our own. Medalla Light even decided to make this project the focus of their entire summer campaign! They will be sharing videos and blog posts about the project, and broadening our reach to spread the important message surrounding conservation of our coral reefs. Their love and appreciation for Puerto Rico's natural resources was obvious to us from our very first communication. We are excited to see what other creative ways we can collaborate to use RGS to enhance our marine ecosystem.

Check out this video they prepared as the launch of the campaign, featuring vocal artist Pedro Capo AND Isla Mar and HJR Reefscaping!! Plus, here's our feature on their blog.

Follow along with our news to learn more about this project as it progresses! Subscribe to our News section to be alerted when we post again, or follow us Facebook !


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