Seaflower: an unexplored and vulnerable asset

The archipelago of San Andrés, Providencia, and Santa Catalina as well as the eight smaller islands such as Cayo Serrana together make up the Seaflower Biosphere Reserve. Photo AFP.
The archipelago of San Andrés, Providencia, and Santa Catalina as well as the eight smaller islands such as Cayo Serrana together make up the Seaflower Biosphere Reserve. Photo AFP.
  • facebook
  • twitter
  • linkedin
With deep regret and disquiet, the biologist Juliana Sintura witnessed the enormous quantity of rubbish that was present on Cayo Serrana’s pristine waters, which are located in the Caribbean Sea. Bottles, flip-flops, oil filters, clothes, lightbulbs, and wood float menacingly in an area that is protected and a very valuable ecosystem.

"There was enough waste to fill fifty or sixty rubbish bags" she said sadly. A large percentage of the waste comes from Haití, Venezuela, Puerto Rico, Panamá, Colombia, and Nicaragua. The Caribbean waters are very connected, particularly for elements that float, which can last months or even years without decomposing.

Serrana, which is 3 km long, 15 km wide, and surrounded by coral atoll is one of the eight smaller islands that make up the Archipelago of San Andrés, Providencia, and Santa Catalina. Together these comprise the Seaflower Biosphere Reserve, which was declared a UNESCO world heritage site in 2000. The other seven small islands are, Roncador, Quitasueño, Bolívar, Albuquerque, Serranilla, and Bajo Nuevo.

As a member of the Colombian Ocean Commission (CCO for its acronym in Spanish), Juliana was working on the project as the general coordinator of the 2016 Seaflower Scientific Expedition. This was an investigative project the purpose of which was to characterize the island's biodiversity, both on land and underwater. Under Juan Armando Sánchez's leadership, the Universidad de los Andes was the institution that organized the expedition.

In 2016, the initiative was supported by Colciencias' Colombia BIO program. "The expedition is one step further to supporting biodiversity; it allows us to continue broadening our knowledge in order to sustainably preserve, look after, and research the huge richness of Colombian ecosystems", asserted Yaneth Giha, director of the entity.

The expedition team arrived in Serrana on 4th August on board the research vessel ARC Providencia, which was under the service of the General Maritime Directorate and the National Navy. The expedition lasted for 29 days and there were two shifts per day. In total, 28 institutions were involved as well as 52 researchers, and there were 113 members of the expedition. There were 22 research projects in areas such as marine and coastal resources, marine invertebrates, the health of the coral atoll, seabed morphology, migratory birds, marine pollution...

"The Seaflower National Plan of Scientific Expeditions is a turning point in the advance of science, technology, and innovation in the research of Colombian maritime territory. It is a national effort in which multiple entities are committed to generating scientific knowledge of the reserve in order to strengthen their criteria of ecosystem unity, which, in turn, allows them to devise management strategies", explains Nacor Bolaños, director of the Corporation for Sustainable Development of the Archipelago of San Andrés, Providencia, and Santa Catalina (Coralina).

The CCO is heading the project: a decision that came from the president’s office. “The visit is also a sovereign act” added the biologist Juliana Sintura, alumni of Los Andes.

It is worthwhile noting that on 19th November 2012 the International Court of Justice in the Hague, as part of a dispute with Nicaragua, issued a ruling that awarded Colombia sovereignty of both the larger islands and all of the smaller islands. However, it stripped Colombia of roughly 100,000 km3 of sea area, which cut the Reserve in two. Since that ruling, Quitasueño and Serrana have been in Nicaraguan waters.

Francisco Arias Isaza, director of the Marine and Coastal Research Institute (Invemar), said to the Colombian newspaper El Colombiano that, “There lies the paradox of the Court´s decision: not understanding that they are integrated structures belonging to a interconnected marine system”.

The Seaflower Scientific Expedition will update the scientific knowledge that we have on the area to date. The data obtained from the work that was carried out there will be included in the National Biological and Marine Information System (SIBNM) and will be promulgated via documents and publications in specialized journals.

The initiative is projected to last five years, with an annual plan to send ships that will visit each one of the cays in the Reserve. Last year the expedition was based in Roncador.

What changes has the Reserve gone through?

The Biosphere Reserve is a marine and biological asset that has an area of 18 million hectares of which less than one percent is made up by landmasses. It constitutes ten percent of the Caribbean Sea, contains 78 percent of the country´s coral areas (it is the world´s third largest coral reef and a ‘cradle of life’), which are the homes of species that are naturally and commercially very valuable such as the parrot fish and the queen conch. They are also home to turtles, sharks, crabs, rajiformes, and lobsters.

After previous expeditions to the area, and during the visit to Roncador in 2015, worrying changes in the ecosystem were documented: the coral reef coverage has declined, vegetation coverage has declined by ninety percent, the plants are plague-infected, and there are more soft than hard corrals.

The biologist Juan Armando Sánchez, who is a lecturer at the Universidad de los Andes and the technical-scientific coordinator of the expedition asserts that, “Last year we saw that the corral was in decline. Previously, there was more than 25 percent coverage in the cay, but now it is less than ten percent. We believe that Serrana could have suffered the same. We need to accept that climate change is killing the reefs”.

Moreover, there are more than one million lionfish —an invasive species inside which researchers have sometimes found more than fifteen smaller fish— in Seaflower’s waters. They have been sighted at fifteen meters below sea level.

The Map of the Seaflower Biosphere Reserve (created by Invemar and Coralina) affirms that, "between January 2009 and May 2010, around San Andres Island, a diving center reported to have captured close to 1200 lionfish by using see-through plastic bags...The Old Providence EcoHamlet Foundation reported that in August 2010 they captured 339 individual fish and they also claimed to have captured the largest fish ever captured in the Colombian Caribbean: it was 38.2 cm long and weighed 840 grams".

The document also recorded the reduction in the number of great-tailed grackle birds that have visited the island, specifically in the old Hotel Isleño area. In 2005 almost 300 visited whereas in 2011 only close to 30 were registered. An additional interesting fact is that all the species of migratory birds that come to Colombia pass through the cays.

Biologist Juan Armando Sánchez affirms that, "Additionally, foraminifera —organisms that are similar to the ameba and whose shell form part of the sand— are indicators of water quality. They are telling us that there are a lack of herbivores and that there are an excess of nutrients in the area: something that we do not really understand, but we know that there is something wrong in the ecosystem".

According to the expert, it was well-known that Roncador had a high density of soft corral (more resistant to coral bleaching and ocean acidification) and a considerable reduction in hard coral. The latter is key for the construction and maintenance of an ecosystem. Soft coral provides habitat but does not calcify as much as hard coral does, and it is still not known if it maintains the balance between erosion and accretion (reef rock formation) as hard corral does when it is healthy.

Indiscriminate overfishing is the greatest threat to the ecosystem. There is currently an excessive extraction of species such as the parrotfish, which is considered to be the gardener of the corral as it helps to clean and keep it healthy, and the queen conch. Overfishing of the parrot fish has led to the increase in algae (as it eats it), which is very detrimental for the corral.

"Although it is not prohibited to fish the parrot fish, we consider it necessary to prohibit this practice in the short term as it is highly vulnerable to extinction and we have to protect the species", states Nacor Bolaños, director of Coralina.

He adds that illegal fishing does not respect bans, which are directly related with the recovery of fish stocks. As a matter of fact, several months ago, a fishing boat from Nicaragua was captured fishing illegally. In the archipelago there are more than 700 species of fish.

There is also a concern that the dense population on San Andrés (it is estimated that 120,000 people inhabit the island, not counting tourists) is having an impact on the island's biodiversity. There is not enough space to dispose of solid and liquid waste, thus much of it is dumped in the sea.

Seaflower, warns experts, is a strategic area, and its appropriate use depends on the welfare of the communities that reside there. The cays represent the inhabitants of the archipelago’s food sovereignty, and their biological resources are valuable for the entire Caribbean.

It is of great importance to know the condition the cay is in, its threats, and the measures that must be taken to avoid degrading the ecosystem and the extinction of species over time. The protection of the Reserve is a national obligation.


  • Logo Facebook
  • Logo Twitter
  • Logo Linkedin