The size of P. miles or P. volitans larvae at hatching is unmeasured, but is likely to be approximately 1.5 mm based on reports for P. lunulata (Mito and Uchida 1958, Mito 1963, in Morris et al. 2008). The specific planktonic larval duration of lionfish is also unknown, although it is estimated to be between 25 to 40 days based estimates for Scorpaena (Laidig and Sakuma 1998, Hare and Whitfield 2003, in Morris et al. 2008).

Richter (2009) hypothesises that the range of the lionfish will reach the Gulf of Mexico and expand south along the eastern coast of South America until it reaches a southern latitude where it cannot tolerate low temperatures (Hare and Whitfield 2003, in Richter 2009). The southernmost sighting has been in Columbia, though there is potential for the lionfish to extend past that (Schofield 2009, in Richter 2009). The northern limit of the range is North Carolina; a functional expansion northward is unlikely unless the lionfish population undergoes a rapid evolution to thermal tolerance; some juveniles have been seen as far north as Long Island Sound, although they cannot become established due to cold winters (Richter 2009). Temperature is a possible factor limiting; the mean chronic lethal minimum is 10°C and the mean temperature of feeding cessation is 16°C, indicating that the lionfish might over-winter on the southeast United States continental shelf, with a northern limit of Cape Hatteras (Kimball et al. 2004).

P. miles and P. volitans ovarian morphology is similar to that reported for D. brachypterus (Fishelson 1978, in Morris et al. 2008) in that these fishes exhibit cystovarian type ovaries (Hoar 1957, in Morris et al. 2008) with ooctyes developing on stalks or peduncles. The oocytes are terminally positioned near the ovary wall, which secretes the encompassing mucus shortly before spawning. \n\n

The seasonality of lionfish reproduction throughout their native range is unknown; invasive lionfish collected off North Carolina and in the Bahamas suggests that lionfish are reproducing during all seasons of the year (Morris et al. 2008).

In the Red Sea, individuals of the closely related P. miles were reported to feed on assorted taxa of benthic fishes including damselfish, cardinal fish, and anthias (Fishelson 1975 1997, in Morris et al. 2008). However, in the Pacific Ocean, P. lunulata were observed to feed primarily on invertebrates including penaeid and mysid shrimps (Matsumiya et al. 1980, Williams and Williams 1986, in Morris et al. 2008). \n\n

Lionfish stomachs can expand over 30 times in volume when consuming a large meal; lionfish are capable of long-term fasting and are able to withstand starvation for periods of over 12 weeks without mortality (Fishelson 1997, in Morris et al. 2008). Lionfish (ranging from 30 to 300g) consume approximately 2.5% to 6% of their body weight per day (at 25°C to 26°C) in their native range; adults (ranging from 300 to 400 g) consume approximately 8.5 g of prey per day, which translates to 230 kg per year for 80 adult fish on a 1 kilometer stretch of coral reef (Fishelson 1997). Preliminary observations suggest that lionfish in their invaded range consume piscine prey at rates greater than in their native range (Morris et al. 2008).

Ecosystem change: While few ecological studies have been conducted (but see Albins & Hixon 2008) it is clear that the lionfish’s presence in the Caribbean is a worrying one. Lionfish are highly piscivorous and reduce the recruitment of juvenile fishes, which in turn disrupts marine ecosystem processes and reduces reef biodiversity (Albins and Hixon 2008; Morris et al. 2008). \n\n

Reduction in native biodiversity: If their populations are allowed to continue growing unchecked, lionfish have the potential to severely reduce reef biodiversity, with the possible extinction of several species; although it is still too early to be definitive, anecdotal evidence from the Bahamas corroborates this premise (Dell 2009).\n\n

Predation: Albins and Hixon (2008) showed that lionfish can drastically reduce recruitment of native fishes on small patch reefs in the Bahamas. They are potentially capable of decimating indigenous reef fish populations in the Caribbean due to their lack of natural predators and voracious appetite (Valdez Mascari & Aguiar 2009). \n\n

Competition: Not only do lionfish consume large quantities of juvenile fish (such as grouper and yellow-tail snapper) but they also out-compete native species (such as scamp, gag, and yellow-mouth grouper) for food (Morris et al. 2008; Dell 2009). \n\n

Economic/Livelihoods: In addition, by reducing populations of commercially important species such as grouper (Albins and Hixon 2008) they may as a consequence damage the economy of island communities which are dependent on such fishing industries. \n\n

Human health: Lionfish are venomous with their spines containing apocrine-type venom glands (Morris et al. 2008). Lionfish venom has been found to cause cardiovascular, neuromuscular, and cytolytic effects ranging from mild reactions such as swelling to extreme pain and paralysis in upper and lower extremities (Kizer et al. 1985, in Morris et al. 2008). The toxin in lionfish venom contains acetylcholine and a neurotoxin that affects neuromuscular transmission (Cohen and Olek 1989, in Morris et al. 2008). Lionfish spines can prove dangerous to divers, snorkelers and aquarium enthusiasts (Morris et al. 2008; Schofield 2009). Stings are not fatal, but intensely painful and often requiring hospitalisation (Morris et al. 2008). Lionfish stings can be treated by heating the afflicted part in hot water (to 45° C) for 30 to 90 minutes and applying corticoids to the area (FishBase 2006); medical attention should be sought immediately (Cayman Islands Government Undated).

Preventative measures: Where the lionfish has not yet become properly established, preventative controls may include education of fishermen and other locals and encouraging the public to kill the fish on-sight and record positional data (Richter 2009). Some countries have urged recreational divers and snorkelers to record locations of lionfish sightings; other governments and programs have given monetary incentives to fishermen to catch and record positional data of lionfish (REEF 2009, in Richter 2009). \n\n

Monitoring: Determining the extent of the lionfish invasion is necessary for effective management (Richter 2009). Organizations such as the Reef Environmental Educational Foundation (REEF) and the United States Geographical Survey-Nonindigenous Aquatic Species (USGS-NAS) have collected data of GPS locations, dates, water depth, and locality description of lionfish sightings (Richter 2009).\n\n

Biocontrol: Groupers, a known natural predator of the lionfish, could hold the key to controlling this invasive species, however, this remains uncertain and unfortunately Atlantic populations of grouper are suffering from over-fishing (IUCN 2009). There is hope that through the establishment of Marine Protected Areas (MPAs) sufficient levels of groupers will return, providing an effective and natural means to control lionfish (IUCN 2009).\n

Physical: In order to control and manage the lionfish invasion, culling programs have been introduced in the Cayman Islands, Bermuda and the Bahamas (4th UK CBD Report 2009; Adam-Whitmore 2009). \n\n

Integrated Pest Management: \nAlthough bio-economic evaluations are necessary to determine the most effective management scheme, Richter (2009) suggests the establishment of a lionfish fishery may prove to be effective (Richter 2009). With the advent of an invasive species fishery, there are certain precautions, however; with the introduction of a potentially economically viable fishery, there lies the risk that people who reap the economic benefits may seek to maintain wild populations of the lionfish (Carlton, Pers. Comm., in Richter 2009).