Coral disease triggers partial closure of Cozumel Marine Park

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Coral disease triggers partial closure of Cozumel Marine Park

October 15, 2019 - 14:07
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The dive community has been “abuzz” about the partial closure of the southern reefs of the island of Cozumel in Mexico, which started on 7 October 2019. To clarify the situation, a group led by the Cozumel Reefs National Marine Park and several environmental groups, initiated a two-month closure of the reefs from Palancar Pier and southward, from 7 October to 15 December 2019, to give these reefs a bit of a rest.

Filephoto by Larry Cohen

Text by Steve Rosenberg
FIle photos by Larry Cohen and Olga Torrey

Over the course of the past year, many of the hard corals around the island have been infected by diseases that were first observed in the Miami area back in 2014. The scientists who have been studying these diseases believe that their source is untreated effluent (or liquid waste) from resorts and/or cruise lines. One of the main reasons for the closure is to bring attention to the seriousness of the problem.

Effective 7 October through 15 December 2019

In a joint action taken by the Secretary of Environment and Natural Resources, the National Commission of Natural Protected Areas (CONANP) and the advisory counsel of the Cozumel Reefs National Marine Park, it was decided that there would be a temporary closure of the southern part of the marine park from the Palancar Pier and southward. It was determined that this closure would take effect on 7 October 2019 and continue through 15 December 2019. The stated reason for the temporary suspension of diving and snorkeling activities in this area was to give the reefs some time to recover.


The background story is that by the end of 2018, Cozumel’s coral reefs had seen a huge decline. Hard corals had been infected by diseases called Stony Coral Tissue Loss, SCTL, and White Band Disease. White Band Disease gets its name from the white bands of dead coral tissue that it forms. None of these diseases should be confused with coral bleaching, which is something entirely different.

The suspected bacterial infections spread rapidly killing many species of hard corals. Healthy Reefs, a group that tracks the health of the Mesoamerican Barrier Reef System, states that the effect of the disease is “unprecedented” as mortality rates are very high and around 30 different types of hard corals are susceptible to it, including brain corals, pillar corals, flower corals and star corals, to name a few.

Reef-building corals affected

Among the particularly troubling aspects of this disease outbreak is that the diseases have affected more than half of the reef-building hard coral species. It has also spread quickly and has a high mortality rate among affected hard corals. According to the Florida Disease Advisory Committee and the Florida Department of Environmental Protection, the scientific community seems to believe that the disease is transmitted primarily through the water column, but speculates that it can also be transmitted by contact.

The first sighting of the destruction of these types of corals was in the Miami area in 2014. In Mexico, it was first seen at Puerto Morelos, 45km south of Cancún, and it made its way to the reefs off Cozumel in early 2018. By late 2018 and early 2019, the disease had spread throughout Pompano Beach, Palm Beach, the Upper Florida Keys, and to parts of the Caribbean, including Jamaica, Saint Maarten, the US Virgin Islands, the Mexican Caribbean, the Dominican Republic, Saint Thomas and Honduras.

The exact cause and source of the disease is unknown, but scientists believe that it is linked to pollution and possibly the presence of seaweed such as sargassum in seawater. The phenomenon occurs as a result of pollutants (and possibly rising water temperatures), which cause the coral polyps to expel the algae on which they feed, and that live in their tissues. The tissues then disconnect from the coral skeleton, the animals die and the reef loses its color.


Researchers are still without solutions to the problem, although the state is working on a massive project, replenishing damaged reefs with laboratory-grown coral. In a couple of areas in the western Caribbean (namely along the coastline of the Mexican mainland and in Honduras), there is an effort underway, to replant hundreds of thousands of “lab-grown” corals on the reef. The goal of the project, which began in 2017, is to re-establish healthy corals, hoping that water treatment efforts will minimize the presence of pollution, the probable source of the bacterium.


The Cozumel Reefs National Marine Park has acknowledged that cruise ships and the mismanagement of waste at coastal hotels in and around the marine park are amongst the most likely causes for the spread of the disease. Although the causal agent of the bacteria is not clear, most scientists think that the bacteria has evolved from pollution (untreated effluent) dumped in the ocean by cruise ships and resorts.

The action taken to close Cozumel’s southern reefs to divers was done so for two reasons. First, the Park wanted to slow one potential cause of the spread of the bacteria, which was physical touching of the coral by divers. Studies have shown that during an average four-hour period on any given day of the week, there have been as many as 2,000 touches by divers in the southern reef area.

Second, and perhaps the more important reason, is that the closure will create an awareness of the problems that the reefs in Cozumel are now facing.

Many people want to know why the partial closure was ordered and why the partial closure was only for the southern reefs (Palancar, Columbia, Chun Chacaab, Maracaibo, Punta Sur and Cielo). I have spent quite a bit of time this year diving in Cozumel, as well as other nearby destinations such as the Bay Islands on Honduras. This year, I observed a lot of SCTLD or “White Band” disease in many areas of Cozumel and the Bay Islands of Honduras. The areas of Cozumel that have been affected by the disease are certainly not limited to the southern reefs.

New regulations

New regulations require that hotels and beach clubs install water treatment equipment. This is certainly a good thing. It also reported at this time that regulations require cruise ship lines to treat their effluent (liquid waste) before dumping it in the ocean. This is extremely important because this is the most likely source of the bacterium that has attacked the corals. Obviously, sewage treatment is very expensive, but this step is an integral part of the long-term solution.

Usage and fees

Based on a study that was undertaken at the request of the Mexican authorities by the German Agency for International Cooperation, there were findings that a)the Cozumel Reefs National Marine Park gets 1.8 million foreign visitors per year; and b) that the average visitor would be happy to pay 3,052 Pesos (US$155.00) per person for use of the marine park.

There is some indication that the park is considering the imposition of new use fees on tourists. Most of these visitors to the marine park would include tourists who come to Cozumel off the cruise ships for just a few hours and a lesser number of tourists who come to Cozumel specifically to dive. I would speculate that, in reality, a very small percentage of the cruise ship tourists, if any, who were told that they would have to pay US$155 to dive or snorkel for a few hours during their one day stay on the island would actually choose to use the park at such a cost.

A more difficult question would be how potential dive tourists would react to a substantial increase of the use fees they are already paying to use the marine park. Cozumel is a wonderful dive destination, which offers incredible encounters with beautiful and unique marine life. However, one of the considerations for many of the divers who come to Cozumel have chosen Cozumel rather than other destinations because it is less expensive.

Dive sites closed

The dive sites that will be closed in Cozumel are all dive sites from the Palancar Pier and southward include:
• All of the Palancar dive sites
• Colombia
• Punta Sur
• El Cielo
• Maracaibo

The good news

The good news for divers coming to Cozumel while the closure is in effect, is that there are many excellent dive sites for divers to visit outside of the closed areas, and they are the ones richest in marine life. The sites that remain open offer excellent opportunities to observe beautiful fish, sea turtles, invertebrates, colorful sponges and healthy corals for which Cozumel is known.
 Some of the excellent sites inside the boundaries of the marine park that are not affected by the temporary closure include:
• La Francesa
• Dalila
• Cedral
• Santa Rosa Wall
• San Francisco
• Punta Tunich
• Yucab
• Tormentos
• The C53 wreck dive
• Chancanaab (Park and Bolones)
• Paradise Reef

There are also several excellent sites that are outside of the marine park. These sites will remain open, and they include:

• Las Palmas Wall
– Central west side
• Villa Blanca Wall
– Central west side
• Miscellaneous shore dives south of San Miguel
• San Juan Reef - Northwest side
• Cantarel Reef – Northwest side
• Barracuda Reef – Northwest side
• El Puente Dos – North end
• Tiburcio – North End
• Hanan - East side
• Cannons – East side

Final thoughts

Multiple meetings have been announced to examine the details of the closure and the effect that the closure has on tour operators, which are concerned about the backlash and economic impacts that the closure will have and the future of the state of Cozumel’s coral reefs. There have been discussions that indicate that if the closures extend past the end of the year, there may be a rotation of the closures throughout various areas of the marine park.

Many marine-park business permit holders have asked to have a Federal Attorney for Environmental Protection (PROFEPA) office in Cozumel that can police the marine park and keep out the many illegal dive and snorkel operators as well as illegal fishing, which occurs daily within the marine park. PROFEPA is the institution in charge of formulating and conducting the inspection and surveillance policy on the conservation and protection of aquatic species at risk and of protected natural areas that include coastal and marine ecosystems.

Finally, Cozumel has much to offer for visiting divers. It is an excellent destination, which offers much to see and experience. There are countless groups that are working hard to address the many issues that the world’s oceans face from population pressures. I, for one, am confident that Cozumel will remain one of the top destinations in the Caribbean for visiting tourists, and I will not hesitate to bring groups of divers here to experience the beauty and excitement of this great dive destination. 