Indo-Pacific : Volitans

Invasion of the Western Atlantic and

Chris Biggs 423-Invasion Ecology

Fall, 2009

Diagnostic Information

Common names: Red Lionfish, Turkeyfish, Red Firefish, Chali (Swahili)

Class – Order - Family - - Pterois – volitans

Identification Guide Figure 1. P. volitans (Hare and Whitfield 2003).

Red lionfish are most notably recognized by length of the fish. Eight spines and thirteen rays their ornate, feathery pectoral fins and their are present on the . Three spines and distinct coloration. Red stripes appear vertically six or seven rays are present on the anal fin. The along the head and throughout the body. They pelvic fins contain one spine and five rays. The are similar to other scorpion fish species and pectoral fins contain 15 rays. (Schultz 1986). share characters such as spiny protrusions and Further distinction between separate species of around the eyes and mouth (Schultz lionfish especially P. miles, can be difficult but 1986). The spines on the dorsal, anal and pelvic has been recently resolved. Spots present on fins are poisonous. glands at the base of the dorsal, anal and caudal fins are generally these spines produce a variety of toxins, which larger in Pterois volitans compared to other can be lethal to other fish (Schultz 1986). The lionfish (Schultz 1986). Figure 2 and 3 shows standard length of lionfish is between 300 - the obvious differences between P. volitans and 380mm (11.8 - 15 inches), although some P. radiata and P. antennata. Differences individuals caught near the coast have between P. volitans and P. miles are much more been larger (Whitfield et al. 2007). Lionfish difficult to discern and should be verified by an have cycloid scales, which along with spine and expert. However, P. volitans is the only species ray counts can be used to distinguish it from recorded to be present in the Western Atlantic other congeners. The pectoral fins can range and Caribbean. from 50% to greater than 100% of the standard

Figure 2. Red lionfish (Public Radio East 2009)

Figure 1. and 2. Red Lionfish (Pterois volitans), tentacles below the eye, long pectoral fins and spots on anal and caudal fin can be used in identification. (Hare and Whitfield 2003)

Figure 3. (P. antennata) and radial firefish (P. radiata) both lack tentacles below the eye and have smaller or absent spots on caudal and anal fins. (Florida Museum of Natural History 2009) Life History and Ecology the two groups correlated to size with smaller lionfish eating more shrimp and larger lionfish The Red Lionfish lives in the warm waters of the eating a larger proportion of fish. Lionfish Indian and Western Pacific Oceans (Schultz either ambush or corral their prey by spreading 1986). They live solitary lives on and around their feathery pectoral fins (Morris and Akins reefs and patches of rocky substrate. They 2009). They ingest prey by rapidly opening typically range from 0-50m in depth (Schultz their mouth, which creates a great amount of 1986) and only during mating season (early to suction. This gape and suck tactic is used by mid spring) have been found to congregate in many species. groups (Ruiz-Carus et al. 2006). Females There is very little information on natural release a mucus egg sac, which is fertilized predators either in their natural or introduced externally. The egg sac rises to the surface and range. The pacific cornet fish has been reported begins degrading in order to release the eggs. The pelagic eggs and larvae grow for 30-40 days during which they are subject to dispersal via currents. (Ruiz-Carus et al. 2006) Juveniles settle on solid substrate and tend to remain in a fairly localized area (Fishelson 1997). They are typically 10-12 mm in length at this point. Thermal tolerance limits for lionfish on the Eastern coast of the U.S. have been shown to be between 10-12C (Kimball et al. 2004). Cessation in feeding behavior occurred around 12C and death at about 10C. Ideal temperature range is between 20-30C. Currently no information on the fecundity of lionfish exists. Lifespan and age or size at maturity information is also unknown. The lionfish diet is composed of a wide variety of prey items including other lionfish (Albins Figure 4. Pacific cornetfish (left), one of the only and Hixon 2008). Morris and Akins (2009) documented predators of lionfish in their native showed that invasive Lionfish in the western range (Florida Museum of Natural History 2009) Atlantic were feeding on a variety of and with ingested lionfish (Maljkovic and and some . The variation between Van Leeuwen 2008). to feed on lionfish, but is limited by the size of Current Geographic Distribution its gape as illustrated in figure 4. feed on lionfish in their introduced range, but it is The native range of red lionfish lies in unclear to what extent (Maljkovic and Van the western Pacific from the southern end of Leeuwen 2008). Grouper are much more Japan to the east coast of . East-west capable of eating full size lionfish as illustrated distribution ranges from to the by figure 4. The lionfish eaten by the grouper Marquesas in the south Pacific (Schultz 1986). was found in the stomach in the position shown. In its introduced region the northern range limit Eating the fish head first can prevent the grouper of lionfish is . The established from getting stung by the spines as they lay population continues south through Florida and down flat when pushed towards the tail-end of the eastern Caribbean. (Whitfield et al. 2002) the fish. has not been well New populations have been spotted in the documented in lionfish neither in their native or western Caribbean from CanCun, to introduced range. There are few cases of ecto- Panama. It is not known if these populations parasites and only one involving an endo- have established and are reproducing. Juveniles parasite in lionfish near North Carolina (Morris have been spotted as far north as Rhode Island et al. 2008). The parasites documented were and New York, but they most likely are unable monogeneans, copepods and . to survive the cold winter water temperatures (Kimball et al. 2004). Water temperature tends

Figure 5. P. volitans native and non-native distribution (Florida Museum of Natural History 2009)

invasions documented in the United States, only 30 were fully saltwater species (Fuller et al. 1999). One well documented and perhaps the only release event of lionfish occurred in 1992 during (Courtenay 1995). The lionfish released were housed in an that broke during the storm and six fish escaped into Biscayne Bay, Florida (Hamner et al. 2007). This release was confirmed by reports of lionfish sightings in the days after the storm.

Figure 6. Non-native distribution of lionfish P. volitans Lionfish have a perennial presence in the (USGS 2009). aquarium trade. They have been classified in the to dictate the limits of habitable territory for top ten ornamental imported to the U.S., lionfish (Whitfield et al. 2007). Temperature an industry that brings in $3.05 million a month has confined lionfish to the northern limit of (Balboa 2003). This information makes it North Carolina, but there is no immediate unlikely that only one introduction event has temperature barrier to the south. Therefore the taken place, but it strongly implicates the spread of lionfish is expected to continue aquarium trade as the most important pathway. throughout the Caribbean and to South America. There are not any documented attempts to create Similarly, the west coast of the U.S. is not likely a lionfish fishery or aquaculture operation in the to see any establishment of lionfish. The water western Atlantic, so these pathways are not temperatures in the eastern Pacific are too cold credited with the invasion (Hare and Whitfield for lionfish to survive. If they are introduced in 2003). Ballast water is well accepted as a major to those waters, it would be more likely they vector of (Wonham et al. 2000). could survive south of Mexico and the west However, no known species have been coast of Central America. introduced to the western Atlantic from the Indo-Pacific via this vector so it is also unlikely History of Invasiveness that shipping was the cause (Hare and Whitfield

2003). The red lionfish has had a relatively The rapid establishment and spread of lionfish is short, although impressive invasion history. the result of a combination of factors, none of Historically, marine fish invasions have not been which are exceedingly steadfast. First, there are very prevalent or successful. With over 500 fish few known predators of lionfish in their native range, let alone in their introduced range. Impact Further, poisonous spines deter would be predators that may not have any experience The invasion of lionfish has been so recent and dealing with this defense mechanism. This has developed so fast that little information is allowed lionfish to inhabit any suitable habitat available on the impact they have exerted on the without regard to pressure. . Given the scenario it is reasonable Attempts to determine the total number of that lionfish are capable of having a large lionfish in the western Pacific and Caribbean are impact. Studies of lionfish in currently underway. Measuring or estimating showed that the presence of lionfish resulted in the abundance of lionfish has been difficult since decreased recruitment of reef fish by up to 80% the amount of effort in counting has varied each (Albins and Hixon 2008). The direct cause of year while general awareness has increased the reduction is attributed to predation by the among the public (Hare and Whitfield 2003). lionfish, which prey on a wide variety of As more people are aware of lionfish and species. One study reported a diet composing of essentially looking out for them, the numbers of 41 species spanning 21 families (Morris and reported sightings are likely to increase skewing Akins 2009). Table 1. ranks the relative the numbers. Whitfield et al. (2007) measured importance of each family of fish eaten by abundance of lionfish between North Carolina lionfish. Lionfish could also have an impact on and Florida and found that they were as the species occupying higher trophic levels. The numerous as grouper, a well-established native venom delivered by the spines could kill fish or species. That study also concluded that sharks that attempt to eat lionfish. This gives competition for resources by grouper is being reduced by over Rank IRI IOP IOI fishing. Not only have lionfish 1 Gobiidae Gobiidae Labridae been released from any natural 2 Labridae Labridae Pomacentridae 3 Grammatidae Grammatidae Gobiidae predators, they are experiencing a 4 Apogonidae Apogonidae Grammatidae reduction in competition for 5 Pomacentridae Pomacentridae Mullidea resources by grouper and 6 Serranidae Serranidae Serranidae snapper. All of these factors 7 Blenniidae Blenniidae Apogonidae have combined with an effective 8 Atherinidae Atherinidae Blenniidae 9 Mullidea Mullidea Atherinidae reproductive strategy to allow 10 Monacanthidae Monacanthidae Monacanthidae lionfish to distribute over a Table 1. Rankings of importance of lionfish prey indices for each fish family large range in a short amount for each importance index. Grouper are members of Serranidae. (Morris and of time. Akins 2009) lionfish the ability to decrease abundance across are one of the areas of the ocean where humans the board if their abundance and density regularly have contact with fish. As more scuba continues to grow unchecked. It is also possible divers and fishermen come in contact with that one of the species affected could be a lionfish, the number of accidents will increase. keystone species, or play a crucial role in coral Stings from lionfish are not usually fatal, but reef ecology. Removal or inhibition of keystone costs associated with care and treatment could species has been shown to have devastating become a factor. Whether it is the cost of effects on (Paine 1995). These are keeping anti-venom and medical supplies on all just speculations about potential impact. The hand or the emergency transportation to medical underlying message is that more research is facilities, these expenses contribute to the impact needed as well as precautionary measures to of lionfish. ensure that these impacts are not realized. Management Strategies and Control Methods In addition to reducing the sheer number of fish, lionfish may be out competing native grouper Currently there are no large-scale management and snapper (Whitfield et al. 2007). These actions in place to deal with the lionfish species are top predators, but their numbers have invasion. Given the rate of dispersion and the been reduced by over fishing (Huntsman et al. estimated numbers of individuals, eradication is 1999). Given the capacity of lionfish to reduce not a feasible option (Hare and Whitfield 2003). the number of prey items available, grouper and Reducing the number of lionfish would be the snapper could experience additional pressure next approach to management, but it has some of and reduced abundance. As of now, lionfish are its own drawbacks. Bounties have been not a commercially important species, so they proposed in exchange for caught lionfish, but the are not prone to the same fishing pressures as bounty would have to be lower than the price grouper or snapper. This impact is double edged offered in the aquarium trade to ensure that the in that lionfish are likely to disrupt the fish are being taken from the wild and not ecological balance as well as have a negative purchased at stores. The current market price effect economically by exerting additional stress for lionfish is ~$40-$100. There has recently on the overfished species. The economic effects been rising interest in lionfish for seafood would be felt through fewer catches of grouper markets. Sean Dimin is currently testing the and snapper as well as efforts to maintain the market in Chicago and New York with a fishery. program he calls Sea to Table. If lionfish do As the population of lionfish increases the indeed become a desirable food item for humans number of envenomations are also likely to it could provide a way to keep their numbers in increase (Hare and Whitfield 2003). Coral reefs check. Although an unintended consequence of interested individuals that are not part of the creating this fishery or offering bounties would scientific community. In 1997 REEF took this be an increase in the number of divers getting “citizen science” approach to a new level. They stung as they try to capture the fish. instituted a program for divers and snorkelers to Although the complete eradication of lionfish is conduct surveys reporting lionfish sightings. unlikely to happen, there is still a possibility that They record the habitat description as well as the they could be eradicated or excluded from presence of other fish species in the area. This localized areas. This could serve to protect information can help scientists and researchers certain areas such as marine reserves. The acquire more information to better focus their island of Roatan, has recently research. This added manpower could provide discovered a lionfish population. The local the extra resources needed to properly manage marine reserve is attempting to remove all or control the invasion of lionfish in the near individuals found within the five-mile long future. protected area. The large amount of SCUBA The REEF program also provides the needed divers visiting this area makes it feasible to service of education and outreach. This area attempt local eradication. Each dive site is plays a major role in any management strategy. visited about once a week by one of the many Hare and Whitfield (2003) recommend this as a diving companies. This makes it more likely way to combat the lionfish invasion specifically. that lionfish will be spotted and removed. Their report also directs future research to A division of the Nation Oceanic and collect information on the reproduction of Atmospheric Administration (NOAA) is lionfish. This is probably the most lacking area beginning research on the trophic impacts of of knowledge. Simply determining the lionfish. They are looking at the diet and fecundity of lionfish would go a long way in energetic demands to determine overlap with predicting their abundance and spread as well as native species, which will provide information to identifying limiting life history stages. aide in assessing the risk to local fisheries and A management approach that has not been reef communities. This project is currently considered, but is gaining support in invasion underway, James Morris is the principle ecology, is including an evolutionary aspect. investigator. Freeman and Byers (2006) studied defense An interesting approach to augment current mechanisms in mussels in response to invasive research is being conducted by the Reef . The mussels displayed different shell Environmental Education Foundation (REEF). thickness when exposed to different species of REEF provides online resources for information . This showed that the mussels had evolved on lionfish to SCUBA divers and other to respond to the non-native crab cues. This situation is directly relatable to the situation Fishelson, L. 1997. Experiments and involving lionfish. It is plausible that fish and observations on food consumption, growth crustaceans are capable of developing the same and starvation in kind of predator response to lionfish cues. brachypterus and Pterois volitans Determining the rate of evolution in this case (, Scorpaenidae). Environmental would dramatically alter management efforts. Biology of Fishes. 50:391–403 Research would then be able to focus on ways to facilitate this evolution. One method described Freeman, A.S. and J.E. Byers. 2006. Divergent by Schlaepfer et al. (2005) would be to subsidize induced responses to an invasive predator the prey until they”learn” to respond to the cues in marine mussel populations. Science. 313: of lionfish. Given the current distribution of 831-833. lionfish, this approach would have to be focused on certain areas because of financial constraints. Fuller, P.L. and L.G. Nico. Williams JD (1999) A similar offshoot would be to subsidize Nonindigenous fishes introduced into potential predators like grouper until they inland waters of the United States. “learn” to eat lionfish. This could combat the American Fish Society. Special publication invasion while at the same time provide a new 27. food source for grouper. Green, S.J. and I.M. Cote. (2009) Record densities of Indo-Pacific lionfish on References Bahamian coral reefs. Coral Reefs 28:107

Albins, M.A. and M.A. Hixon. 2008. Invasive Hamner, R.M., D.W. Freshwater and P.E. Indo-Pacific lionfish (Pterois volitans) Whitfield. 2007. Mitochondrial cytochrome reduce recruitment of Atlantic coral-reef b analysis reveals two invasive lionfish fishes. Marine Ecology Progress Series. species with strong founder effects in the 367: 233–238 western Atlantic. Journal of Fish Biology.

71:214–222 Courtenay, W.R. 1995. Marine fish

introductions in southeastern Florida. Hare, J.A., and P.E. Whitfield. 2003. An American Fishery Society Introduced Fish integrated assessment of the introduction of Newsletter. 14:2–3 lionfish (Pterois volitans/miles complex) to

the western Atlantic Ocean. NOAA Technical Memorandum NOS NCCOS 2. Pacific red lionfish, Pterois volitans 21 pp. (Scorpaenidae), in Florida: evidence for reproduction and parasitism in the first Huntsman, G.R., J. Potts, R.W. Mays, and D. exotic marine fish established in state Vaughan. 1999. Groupers (Serranidae, waters. Biological Conservation. 128: 384- Epinephelinae): endangered apex predators 390. of reef_communities. American Fish Society. 23:217-231 Schlaepfer, M.A., P.W. Sherman, B. Blossey Maljkovic, A. and T.E. Van Leeuwen. 2008. and M.C. Runge. 2005. Introduced species Predation on the invasive red lionfish, as evolutionary traps. Ecology Letters. 8: Pterois volitans (Pisces: Scorpaenidae), by 241-246. native groupers in the Bahamas. Coral Reefs. 27: 501 Schultz, E.T. 1986. Pterois volitans and : two valid species. Copeia. 1986: Morris, J.A., J.L. Akins, A. Barse, D. Cerino, 686-690. D.W. Freshwater, S.J. Green, R.C. Munoz, C. Paris and P.E. Whitfield. 2008. Biology Whitfield, P.E., J. Hare, A.W. David, S. Harter, and ecology of the invasive lionfish, R.C. Munoz and C.M. Addison. 2007. Pterois miles and Pterois volitans. Abundace estimates of the Indo-Pacific Proceedings of the 61st Gulf and Caribbean lionfish Pterois volitans/miles complex in Fisheries Institute. the Western North Atlantic. Biology Invasions. 9:52-64 Morris, J.A. and J.L. Akins. 2009. Feeding ecology of invasive lionfish (Pterois Wonham, M.J., J.T. Carlton, G.M. Ruiz, and volitans) in the Bahamian archipelago. L.D. Smith. 2000. Fish and ships: relating Environmental Biology of Fishes. 86:389– dispersal frequency to success in biological 398 invasions. Marine Biology. 136:1111-1121.

Paine, R.T. 1995. A conversation on refining the Other Resources concept of keystone species. Conservation

Biology. 9(4) 962-964. Reef Environmental Education Foundation

(REEF) Ruiz-Carus, R., R.E. Matheson, D.E. Roberts www.reef.org and P.E. Whitfield. 2006. The western The Economist. Science and Technology. Eat Department of Zoology for the ecosystem: a heartening tale of business Oregon State University and the environment. 2009. Corvallis, OR 97331-2914 http://www.economist.com/sciencetechnology/di 541-737-5364 splaystory.cfm?story_id=14637325

United States Geological Survey (USGS)

Nonindigenous Aquatic Species www.usgs.gov

Florida Museum of Natural History www.flmnh.ufl.edu/fish/Gallery/Descript/RedLi onfish

NCCOS Project Explorer (NPE) NOAA http://www.ccfhr.noaa.gov/stressors/invasivespe cies/Lionfish_

Expert Contact Information

James Morris NOAA Center for Coastal Fisheries and Habitat Research 252-728-8782 [email protected]

Paula Whitfield NOAA Beaufort Laboratory (252) 728-8714 [email protected]

Dr. Mark Hixon