Karin Jakubowski, Ph.D., is a 2021 graduate of the Ph.D. Program in Environmental Studies at Antioch University, New England

Dissertation Committee:

  • James Jordan, Ph.D., Committee Chair
  • Thomas Webler, Ph.D., Committee Member
  • Alida Ortiz Sotomayor, Ph.D., Committee Member


Vulnerability Analysis, Coral Reefs, Puerto Rico, Marine Recreation, Scuba Diving, Snorkeling

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The purpose of this dissertation is to add knowledge to coral reef management by designing and testing a methodology to assess the vulnerability of select coral reefs to diving and snorkeling recreational activities within La Cordillera Nature Reserve, Puerto Rico. Vulnerability research consists of three main components. This includes measuring exposure to the stressor, characterizing the sensitivity of the exposure, and characterizing the capacity to act. In the context of this research, exposure refers to the number of potentially harmful actions that recreational snorkelers inflict on coral reef ecosystems when they contact the reef and includes the number of individuals over the reef, the duration of time spent over the reef, and the depth of the coral in relation to the location of individuals. Sensitivity includes the qualities that make some corals experience more impact when exposed to the same stressor (the snorkeler and diver behavior) and include the morphology of the coral and the topography of the reef. Finally, adaptive actions in this case refer to decisions and actions taken by a variety of individuals within the tourism industry. This includes crew decisions about dive and snorkel trips, interactions with divers and snorkelers during trips, and the attitudes, knowledge, and beliefs of divers and snorkelers about coral reefs.

Dive and snorkel data were collected between January 2011 and June 2014. My findings indicate that some reefs within La Cordillera Nature Reserve, Puerto Rico are vulnerable to snorkeling activities. Icacos Island reefs have a high exposure to contacts, most likely because of the depth of the coral in relationship to the snorkeler. Fin contacts were the most potentially damaging behavior. Topographic features of these reefs may lead to more contacts. The number of potentially damaging contacts for snorkelers was high, (0.28 contacts per minute) at La Cordillera Nature Reserve when compared to the only other location where snorkeler contact rates were observed (St. Lucia). When this frequency is multiplied by the number of visitor-minutes spent at reefs on a yearly basis, the scale of the problem can appear to be a significant factor in increasing vulnerability.

Reefs within La Cordillera Nature Reserve are also vulnerable to scuba diving activities. Dive operator data analyzed found the average number of trips during both the peak and non-peak season was the same, 107 trips. The average number of divers per trip was nine. The dives lasted from 35 – 51 minutes with a mean of 45 minutes at an average depth of 50 feet. This averages to slightly more than 3,200 divers per year, which is below all of the other recommended carrying capacities in coral reef locations globally. While the average number of divers may be below carrying capacity, the contact rate for divers observed in La Cordillera Nature Reserve, was 0.5 contacts per diver per minute. This rate is five times higher than all but two other coral reef locations where research on number of contacts with reefs was conducted. Similar to other research, divers who use cameras while diving had significantly more contacts with the reef than non-camera users. The reefs at one of the main dive sites, Diablo Cay, had a high percentage of soft corals. The unpredictable movement of these corals can make it difficult for a diver to avoid a contact and may be a contributing factor to why the contact rate per minute is higher for divers in Puerto Rico.

Coral reef related tourism and recreational activities rank among one of the most important industries in Puerto Rico by providing jobs, supporting local economies, increasing visitor knowledge of coral reefs, promoting pro-environmental values, and helping to create a conservation ethic. Healthy and resilient coral reef ecosystems are essential to the tourism industry, specifically scuba diving and snorkeling operations. Given the current and expected growth in tourism and marine recreational activities, the problem of recreationally-based damage to coral ecosystems will continue to grow. This dissertation can inform management decisions designed to mitigate the impacts that dive and snorkel tourism have on coral reef systems in order to decrease the overall vulnerability of these systems. Recommended measures can be implemented to reduce the vulnerability of the system which then can continue to provide benefits to those who depend on this economy for their livelihood and well-being. Specifically, actions that decrease exposure is a tangible possibility. Reducing contacts is one such measure. Actions to encourage pro-environmental behaviors at the reef include revising briefings that reinforce etiquette at the reef and social norms that empower snorkelers, non-certified divers, and certified divers to make a greater effort to not contact the reef. Crew members should consider the skill and perceptions of their guests, mooring use, in water supervision, interventions, attending best practices workshops, and emphasis on the content and delivery of coral reef etiquette messages. Such measures are important for reducing the vulnerability of coral reefs to recreational activities, conserving these ecosystems, and sustaining the tourism economy of Puerto Rico and beyond.


Karin Jakubowski

ORCID Scholar ID# 0000-0002-0411-9653