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Goliath Pacific groupers under threat in a biodiversity hotspot

“If you miss the first shot, it might try to eat you,” Apsalon, a local spear fisherman, told me during an interview for my research. He was once half-swallowed by a massive goliath grouper near one of his favorite fishing spots, Playa Blanca in Chocó, Colombia. Although they may sound terrifying, these massive fish are...

“If you miss the first shot, it might try to eat you,” Apsalon, a local spear fisherman, told me during an interview for my research. He was once half-swallowed by a massive goliath grouper near one of his favorite fishing spots, Playa Blanca in Chocó, Colombia.

Although they may sound terrifying, these massive fish are so fascinating that I have devoted much of my scientific career to studying them. And while they may seem threatening, they are actually the ones under threat.

Groupers in Colombia and worldwide fetch high prices in markets due to their high-quality flesh. Unfortunately, groupers are particularly vulnerable to overfishing. They take many years (typically, more than five) to become sexuality mature, and many of them gather by the hundreds to reproduce — a behavior known as spawning aggregations. Such gatherings are targeted by fishermen, as more fish can be caught in less time and at lower cost.

The global demand for groupers in combination with the lack of fisheries management is driving many grouper species toward extinction. In 2013, a study by Sadovy et al. assessed all grouper species and found that 12 percent of grouper species are at risk of extinction, 13 percent are near threatened, and 30 percent are currently defined as “Data Deficient,” meaning that not enough information is known about the species to determine their status.

The Pacific goliath grouper (Epinephelus quinquefasciatus), known locally as mero, is integral to the fish trade in Colombia. This grouper is the biggest reef fish of the Tropical Eastern Pacific — it reaches up to 2.5 meters (more than 8 feet) in length and weighs up to 200 kilos (440 pounds). Despite its enormous size and importance in the market, little is known about the biology of this giant, leading to its classification by the IUCN Red List of Threatened Species as Data Deficient. Important information for conservation and management of this grouper, such as population size, reproduction, and movements is currently lacking, making it difficult to direct conservation efforts.

For my research, I worked in Colombia’s Chocó region — a hotspot for biodiversity and one of the last places with an active fishery of the Pacific goliath grouper. I interviewed fishermen, surveyed local markets, analyzed historical landing data, and conducted underwater visual census to understand different aspects of the Pacific goliath grouper life history. I was attempting to create a more holistic picture of the fishery dynamics and possible threats that the grouper might be facing in Colombia.

Fishermen sorting their catch to sell at market. Credit: Carolina Chong Montenegro

So big it could eat a human

During interviews, older fishermen shared more detailed information about the life history, and the traditions and folklore around this grouper. They used to call it the “wild-beast,” for the strength and power with which the fish fought to survive, and because the grouper was so big it could eat a human. Not everyone could go out and fish this giant. Fisherman had to wait for the right moon and the right tide to find a hungry goliath, and the only people that would go out to confront this fish were the experienced.

Carolina interviews a local fisherman in Jurubirá. Credit: Paul Tompkins

Times have changed, as have the views of younger generations of fishermen about the species. For them it is no longer the wild beast, it is now a rare fish that they occasionally catch, often at much smaller sizes than those their grandfathers fought. Fishermen attribute the decline in Pacific goliath grouper populations to destructive fishing practices, such as the use of poison and dynamite, as well as the destruction of their habitat, increasing fishing pressure, and most recently, spearfishing.

Measuring Goliath Grouper in Nuquí. Credit: Paul Tompkins

My fish market surveys also revealed an interesting dynamic. In contrast with other countries where bigger fish yield higher and better prices, in Colombia people pay more for smaller goliath groupers (less than 30 cm, about a foot). This specific demand leads fishermen to direct their fishing effort to target small and immature groupers. This local demand jeopardizes the Pacific goliath groupers’ survival in the Chocó. Fishermen are threatening their own future by fishing groupers before they get a chance to breed.

We have taken grouper species to the brink of extinction before. In the 1980s, numbers of Atlantic goliath groupers in U.S. waters crashed due to uncontrolled fishing, and they were declared critically endangered. In the Caribbean prior to 1990, Nassau groupers in aggregations of 30,000 fish were recorded. In 2007 a new survey found that the few remaining aggregations contained 1,000-5,000 fish, a reduction of 83 percent in a decade.

Goliath Groupers arriving in Buenaventura fish market. Credit: Carolina Chong Montenegro

The return of the goliath grouper

However, we have learned that with education, management, and better fishing practices, we can help bring these species back to our ecosystems. The establishment of a fishing moratorium enacted in 1990 by the U.S. Government banned the fishery of the Atlantic goliath grouper. Since then, their populations have rebounded and are currently producing great revenues for the ecotourism industry in Florida.

For the Nassau grouper, temporary bans have been established in the Bahamas, allowing this grouper to reproduce and help to sustain populations for both fishing and tourism.

We need these giant fish for the health of our oceans and for the people that depend on them. Groupers are top predators and removing them can result in unbalanced ecosystems. Moreover, they provide livelihood to 55,000 people in Colombia alone, and hundreds of thousands of others around the world.

We can take these successful strategies and use them as examples for other endangered or threatened fish species. For the Pacific goliath grouper, conservation strategies are just starting.

Together with WWF Colombia, I am planning to use the results of my research to develop strategies and conservation plans for the Pacific goliath grouper in Pacific Colombia. We plan to work with local communities to teach the importance of these giants in their ecosystem and to promote better fishing practices that lead to a more sustainable use of marine resources.

Colombia is just the first step of this journey to promote the conservation of the Pacific goliath grouper across the Tropical Eastern Pacific. This is just a little step towards a secure future for this giant fish.

Carolina Chong Montenegro is a fisheries ecologist focusing on rare and threatened species of groupers. Carolina received her master’s degree at the University of Bremen, Germany, where she studied the biology and fisheries of the fascinating Pacific goliath grouper in Colombia. Carolina plans to continue her work studying small-scale fisheries in the Tropical Eastern Pacific and their impact on ecologically important and commercially exploited fish species. She aims to actively integrate local communities into the research process and apply interdisciplinary approaches for developing sustainable fisheries. Carolina is a 2015 National Geographic Young Explorer grantee and is part of the 2017 Young Explorer Leadership and Development Program.

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