On the 21st of February, 2014, the NHRCP team surveyed an area on the western side of the island for a suitable site to install a new mooring line, but ended up involved in a large underwater clean-up. A short while into the dive, we came to a ring of net, at least 50 meters in length and over 2 meters high in places, that had drifted in from deeper water and had finally come to a stop after being caught on pockets of branching coral at the edge of the reef. Now, I must mention that, nets drifting in and being caught on pinnacles and reefs is not a novel event but it is something that demands attention in the rare situation that it does happen.
Often older nets that have settled and become a part of the substrate are left alone, especially those made of natural fibers as opposed to synthetic polymers. These often become good habitat for a range of species and removal would cause more harm than good. However this was a new, gill net, which has been designed to ensnare fish completely especially around their gills. To get to the position it was now in, this net must have spent much of its time since being lost/discarded, till being caught, as a ghost net. This is a wall of net that drifts in the water column ensnaring anything that gets caught in it.
As we sat amongst these walls of meshing, reminiscent of an arena or a cage, a number of contrasts came to mind that allowed me to explore the work we were doing from a wider perspective. Our team, that manages, maintains and develops artificial dive sites and reefs had been presented with a completely different type of artificial dive site, which I had come to realize was precisely what we were within. This was an area that had been transformed from an unassuming, healthy portion of reef edge, to an area segregated, and in this case, enclosed in walls of man-made origin. A team that makes a habit of providing structure and habitat needed to remove something that does the exact opposite.
The second contrast that came to mind was not to do with the structure and purpose of the temporary dive site but the inhabitants. At first glance, much like the artificial reefs, teams of smaller fish swam in an out of the artificial material that had attached itself to their coral homes. However when you sit and look at the details, the damage becomes apparent. Edges of large coral colonies had bleached themselves in an attempt to deal with the physical stress of the net and when compared the nearby colonies that remained untouched, they seemed largely devoid of life.
There were far fewer living crabs within the edges of affected colonies and portions that had be completely smothered had been abandoned by even the schools of damselfish that were an integral part of the habitat. Even if you chose not to look too close, swimming along you could see ensnared within the nets were lifeless groupers, large crabs missing limbs and even a blue spotted ray in this case.
The final contrast that came to mind was that of the role of people within an ecosystem. The fisherman that undoubtedly had not wanted to lose their net were not directly at fault here, the new zoning regulations on the island restricts any commercial fishing activities to outside of 3km from the island so chances are this net had drifted in from at least that distance. These people had affected an ecosystem indirectly and unintentionally and in the past, this would have been a problem with no solution.
However, people do effect the ecosystem, all ecosystems and we will continue to do so, except now, at least for a small island, it is both intentional and beneficial. Nothing illustrated this better than within the 60 minutes it had taken to find the net and take action, the walls of the site around me were removed and the reef was returned as best as possible to much of its former state. Given what was caught in the net it is safe to assume that this net had not traveled too far and had been relatively benign, but not all reefs are this lucky, nor all nets this tame.
Studying conservation taught me how species specific intervention is rarely as successful or beneficial when compared with an ecosystem wide approach, and how, even at the ecosystem level, prevention is better than cure, but both simultaneously achieved the best results. We had started the day seeking to install a mooring line to prevent boats anchoring onto the reef, we had found a net that had drifted in and caught on coral, and worked to remove it to prevent further damage. Our conservation priority had quickly shifted from prevention at the start of the dive to one of damage control and cure upon finding the net. In either case, we affected the ecosystem, and now days, that is something to be proud of.