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Lionfish in Brazil are threatening the local ecosystem

Invasive lionfish are destroying the natural environment of the Florida and Caribbean. This invasive species has reached Brazil, leading to a new problem where locals do not know how to properly care

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The lionfish is a particularly harmful invasive species in today’s oceans. And now their destructive territorial expansion has reached as far south as Brazil.

Lionfish have been making the long journey south. After being discovered in the Gulf of Mexico in 1985 (likely after being released from the aquarium trade), they rapidly spread to the East Coast and the Caribbean. In roughly 2010, they arrived at the South American coast.

However, the species became stagnant near the Venezuelan and Trinidadian islands. For 10 years, the fish were unable to make their way south due to physical obstacles such as a confluence of currents and the freshwater flowing from the Amazon River into the Atlantic. But beginning in the 2020s, when scientists were preoccupied with the COVID-19 pandemic, lionfish began to sneak past the barrier and head south.

A new study published in Frontiers in Marine Science reports that dozens of lionfish have been seen along 150 miles of Brazil’s coastline. When the water was clear enough to do so in March, April, and May of this year, researchers and fishermen were able to document 72 individuals swimming together. A high population density is indicative of the establishment of new, viable populations, a potentially disastrous and usually irreversible development for an invasive species.

According to marine ecologist and study author Marcelo Soares, “lionfish have already managed to cover 700 kilometers [435 miles] of coastline since March 2022.” Moreover, he mentioned that there are now more than 300 people. We predict that lionfish will spread to the remaining 6,000 kilometers of the Brazilian coast within two years if immediate measures are not taken.

Many researchers believed that the only question was not whether or not fish would continue their migration south, but when.

Osmar Luiz, an aquatic ecologist at Australia’s Charles Darwin University who was not involved in the study, says, “We knew once they made it through the barrier at the Amazon, they would spread like fire.”

Native to the Indo-Pacific, the lionfish is the most destructive invasive fish. They eat native species and throw off food webs wherever they go, wreaking havoc on ecosystems. As a result, they are considered among the most destructive invasive fish in the world. Since their introduction to the Indian Ocean and the Suez Canal, lionfish have spread to the Mediterranean Sea, where they have now established populations. If they are able to “hitchhike” on currents from the Brazilian coast, Luiz does not think it would be long before they arrive in West Africa.

Every two to four days, lionfish produce thousands of eggs, adding to their already devastating impact. Their backs are covered in poisonous spines, and they are highly adaptable to new environments and foods. Millions of their larvae can be spread across a wide area by currents and even hurricanes. However, the threat they pose is often underappreciated because there are few natural predators in their invaded ranges.

“They have so many traits that make them successful,” says Nicola Smith, a marine ecologist from the University of British Columbia who was not involved in the new study. The fact that they have made it to Brazil after a quick trip down the Atlantic coast doesn’t surprise me at all.

To quote Soares, “the lionfish is a voracious predator,” and an invasion of lionfish can spell doom for delicate ecosystems and their inhabitants. In contrast to other predators, lionfish will continue to pursue the last remaining members of a prey species until they are extinct.

Lionfish prey on other organisms, making endemic species (those that can only be found in one place) an easy target. Moreover, endemic species abound in Brazil.

Brazil’s lionfish

Soares and his colleagues compiled reports from scientists, fishermen, and social media users to establish a definitive record of the lionfish population boom along the Brazilian coast. More than half of the survey’s 72 individuals were located in close proximity to artificial reefs and other man-made structures used by locals for fishing.

Concerns about the future of fisheries have been sparked by this, Soares says. Food security in a region with high levels of social inequality relies heavily on the coast of Brazil, where there is a lot of artisanal fishing activity.

In the Bahamas, for example, lionfish effectively killed off grouper to the point where fishing for grouper was restricted. Snapper and grouper are two economically important fish that could be reduced to low numbers. Recovering grouper populations

At the time of the survey, lionfish were discovered hiding in waters that were extremely clouded by sediment. This complicates the widespread practice of controlling invasive species by means of spear-gun fishing, in which divers aim their weapons at the fish and impale them with their spears.

Haemulon squamipinna, a small, yellow-striped fish vital to coastal subsistence fisheries, is one of at least 29 fish species endemic to Brazilian waters that are especially vulnerable to lionfish, according to a recent paper. Many species found on rocky archipelagos such as Fernando de Noronha have extremely small ranges—some, according to Luiz, are contained in just a few square meters.

Soares claims that “we don’t yet know all of our marine biodiversity,” especially when it comes to rare and cryptic species. Local population declines among rare and cryptic species are possible if lionfish populate these habitats at the same densities they have reached in the Caribbean.

Since lionfish have already begun breeding in Brazilian waters, their further spread is only a matter of time.

“Once [lionfish] are in the establishment stage, you can fish and fish and fish as much as you want,” says Smith. But you’re fighting an uphill battle because they’ll keep replacing themselves.

Mastering lionfish can be difficult.

Taking fish out of a population would reduce the number of that species there. Smith, however, says that you shouldn’t expect that with lionfish.

Smith says that lionfish can quickly recolonize after being removed. The saying “The more lionfish you cull, the more rise up from the deep to replenish what you removed” rings true because lionfish migrate to areas with smaller lionfish populations.

Smith estimates that about half of the lionfish that are caught in traps escape, despite human efforts to reduce lionfish populations through fishing tournaments, which can quickly remove many individuals over a large area. There has been an effort made by chefs to popularize lionfish as a seafood dish.

Making a non-native fish with poisonous spines into a popular dish in the area is no easy task. Many people wrongly assume that lionfish are poisonous to eat. Filets, while tasty, are small, and they are more difficult to hunt with a spear due to their dangerous spines.

Smith maintains that it is still worthwhile to attempt cooking lionfish.

Many lionfish have graced my plate. “It’s good, it tastes like grouper,” says Smith.

Complete eradication may be impossible, but reducing their numbers can help prevent irreparable harm to native species. Luiz says the next step is to monitor where lionfish are going to stop them from establishing new populations. It will be necessary to keep an eye on distant archipelagos and other offshore areas rarely visited by humans.

This battle is crucial to the survival of Brazil’s indigenous species.

Managing them so that “none of the native species are driven to extinction” is Luiz’s top priority.