The Bermuda Shark Project and OCEARCH’s Great White Shark tagging programme have recently produced valuable insight and impressive imagery with respect to our ocean’s apex predators.

Although both the tiger shark and great white shark are designed for stealthy predation, have a keen sense of smell, and are capable of high speed attack, it is suggested here that these majestic fish are not the most efficient killers in our waters.

The invasive lionfish, a species of carnivorous fish naturally found in the Indo-Pacific Ocean, has made its way to Bermuda and is now eating its way through our endemic reef fish species with reckless abandon. This super predator hovers motionless near its intended victim before carrying out a rapid strike. Sometimes the lionfish will extrude water jets to orient prey towards its mouth before striking (it also confuses and distracts the prey, making them an easier target).

And strike it does. Local findings have recorded that lionfish are eating a wide array of species in large numbers. For example, a research team (with members from BIOS, the University of Massachusetts, the Department of Environmental Protection, BAMZ/BZS, and the Ocean Support Foundation) working locally have been surprised to find lionfish which have ingested octopus, a rare species of squat lobster commonly found in very deep water, swimming crabs, and even one species of shore crab that is typically found in just inches of water.

The range of fish species that have become prey is just as shocking. The research team found rare species like peppermint basslets and cryptic species like two-spot cardinalfish and pearl blennies, and all the more usual reef fish like parrotfish, wrasse, coney, and grunts in huge numbers.

Unlike the sharks mentioned above, the lionfish is un-recognised as a predator by our reef fish and therefore is camouflaged in plain sight, eating anything in its path. In fact, some lionfish have been found with massive deposits of fat within their gut cavities caused by eating at a rate entirely in excess of their naturally occurring Pacific counterparts. Our local reef species are blindsided, and there are no existing predators in the Atlantic to keep numbers in check. Attempts at ‘teaching’ reef fish to eat lionfish have been unsuccessful.

The lionfish is reproductively unmatched as well. Each female fish is capable of laying 30,000 eggs every 3-4 days all year round - about 2,000,000 each year.

Several studies have shown that these eggs are capable to widespread disbursement, especially during the pelagic larval stage. For example, lionfish larvae from eggs released in the Bahamas can be carried as far as New England via the Gulfstream current – likely how they arrived in Bermuda.

The knock-on effects of this new predator are widespread. Perhaps the most obvious is the reduction in numbers of our preferred reef species: snapper, porgy, rockfish etc. which are gobbled up in their infancy. A less obvious impact, (referred to as a trophic cascade, much like a domino effect) is where the lionfish eat herbivores (like parrotfish) which eat the algae commonly found on our reefs. These fish carry out the essential function of cleaning the algae growth on our reefs which enable our corals to ‘breathe’ and function normally. Without the regular cleaning, the algae will growth out of control, the coral will die and our protective reef barrier will depreciate. This reef depreciation has been well documented in the Bahamas.

The good news is that these lionfish taste great, and we (Bermudians and residents) are empowered to respond to the invasion by killing lionfish. In fact, once obtaining a permit (for more information, contact permits@oceansupport.org), SCUBA spearing is permitted in our waters. As one would expect, there are no bag limits on lionfish. There are also groups that are looking into designing traps that target lionfish based on the lobster trap concept. Controlling the population of lionfish by removal is widely discussed in other heavily impacted regions like the Bahamas, Mexico, Cayman Islands and the Florida Keys. Studies (Morris et al 2011) indicate that large numbers of adult lionfish need to be removed every month (approximately 27%) to decrease the population. While this may be unrealistic at present, it serves as a reminder of scale of the task at hand.

Keep in mind that it is important to remember to handle these fish with great care - they have venomous spines that can cause serious injury. Fortunately, the spines can be cut off quickly and easily with any pair of scissors, after which the lionfish can be safely handled like any other fish. Remember, there is no venom in the flesh of this tasty fish!

Thankfully not-for-profits like BIOS, Ocean Support Foundation, Bermuda Ocean Explorers, Groundswell and others are taking a leading role in spreading the word about the control and impact of these invasive predators.

Greenrock would like to reiterate the call for each and every one of us to play an active role in curbing the invasion. This role can be simply telling your local grocer or fish vendor that you would like to buy lionfish in future, writing a letter to your respective member of Parliament and or the Minister of the Environment imploring faster and substantial action to slow the invasion, or even taking the course, obtaining a permit and culling the population before our reef system is permanently impacted.

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Greenrock, www.greenrock.org, is a local non-profit organisation (#704) established to engage the community to share solutions for a sustainable Bermuda.