Distribution and Length Frequency of Invasive Lionfish (Pterois sp.) in the Northern Gulf of Mexico

The purpose of this communication is to document continued spatial expansion of lionfish farther west into the northern Gulf of Mexico. Furthermore, we provide the first length— mass relationships and length frequency information for lionfishes captured within the northern GOM based on data collected as part of a broader on—going study of lionfish life history in this region

Comparison of Age and Growth Parameters of Invasive Red Lionfish (\u3ci\u3ePterois volitans\u3c/i\u3e) Across the Northern Gulf of Mexico

Invasive red lionfish (Pterois volitans) have spread rapidly throughout the northern Gulf of Mexico (GOM) partly because of their high growth rate. Red lionfish were collected from the northern GOM across 3 ecological regions from 2012 through 2015. For male and female red lionfish, relationships between weight and total length (TL) were differnt by ecological region. Males acheives a greater mean weight adjusted for TL (333.6 g [standar errer (SE) 3.6]) than females (195.1 g [SE 3.7]). A subsample of 1607 pairs of sagittal otoliths (from 744 males, 716 females, and 147 fish of unknown or undetermined sex) was used to assign ages. Ages ranged from 0.0 to 4.5 years (mean: 1.4 years), and these estimated ages and the dates of capture for specimens confirm the presence of red lionfish in the northern GOM in 2008, 2 years prior to the first detection of this species there. There were differences in age and rowth between sexes within and among ecological regions, with males achieving higher growth rates and larger asympototic lengths than females (all comparions:

Low Pufferfish and Lionfish Predation in Their Native and Invaded Ranges Suggests Human Control Mechanisms May Be Necessary to Control Their Mediterranean Abundances

The silver-cheeked toadfish (Lagocephalus sceleratus, from the pufferfish family Tetraodontidae) and the Pacific red lionfish (Pterois miles, family Scorpaenidae) have recently invaded the Mediterranean Sea. Lagocephalus sceleratus has spread throughout this entire sea with the highest concentrations in the eastern basin, while more recently, Pterois miles has spread from the Eastern to the Central Mediterranean Sea. Their effects on local biodiversity and fisheries are cause for management concern. Here, a comprehensive review of predators of these two species from their native Indo-Pacific and invaded Mediterranean and Western Atlantic ranges is presented. Predators of Tetraodontidae in general were reviewed for their native Indo-Pacific and Western Atlantic ranges, as no records were found specifically for L. sceleratus in its native range. Tetraodontidae predators in their native ranges included mantis shrimp (Stomatopoda), lizardfish (Synodus spp.), tiger shark (Galeocerdo cuvier), lemon shark (Negaprion brevirostris), sea snakes (Enhydrina spp.), catfish (Arius spp.), cobia (Rachycentron canadum), skipjack tuna (Katsuwonus pelamis), and common octopus (Octopus vulgaris). The only reported predator of adult L. sceleratus in the Mediterranean was loggerhead turtle (Caretta caretta), whereas juvenile L. sceleratus were preyed by common dolphinfish (Coryphaena hippurus) and garfish (Belone belone). Conspecific cannibalism of L. sceleratus juveniles was also confirmed in the Mediterranean. Pufferfish predators in the Western Atlantic included common octopus, frogfish (Antennaridae), and several marine birds. Predators of all lionfish species in their native Indo-Pacific range included humpback scorpionfish (Scorpaenopsis spp.), bobbit worms (Eunice aphroditois), moray eels (Muraenidae), and bluespotted cornetfish (Fistularia commersonii). Lionfish predators in the Mediterranean included dusky grouper (Epinephelus marginatus), white grouper (Epinephelus aeneus), common octopus, and L. sceleratus, whereas in the Western Atlantic included the spotted moray (Gymnothorax moringa), multiple grouper species (tiger Mycteroperca tigris, Nassau Epinephelus striatus, black Mycteroperca bonaci, red Epinephelus morio, and gag Mycteroperca microleps; Epinephelidae), northern red snapper (Lutjanus campechanus), greater amberjack (Seriola dumerilli), and nurse shark (Ginglymostoma cirratum). The sparse data found on natural predation for these species suggest that population control via predation may be limited. Their population control may require proactive, targeted human removals, as is currently practiced with lionfish in the Western Atlantic.</jats:p

Life History of the Non-Native Invasive Red Lionfish (\u3ci\u3ePterois volitans\u3c/i\u3e) in the Northern Gulf of Mexico

Invasive Red Lionfish (Pterois volitans) were first detected in the northern Gulf of Mexico (nGOM) in 2010 and since then their numbers have increased dramatically. From 2010 to 2015, more than 15,000 Red Lionfish were collected opportunistically from the nGOM for this study. Length and weight relationships differed significantly among ecoregions by sex and there was clear sexual dimorphism in size with males being larger and heavier. Red Lionfish age ranged from 0-4.5 years old and males achieved greater growth rate (K) and asymptotic maximum lengths (Linf) compared to females and these parameters were also different by ecoregion. Total length at 50% maturity was greater for females compared to males. Histological examination of female gonads resulted in the confirmation of asynchronous oocyte development. Additionally, the accuracy of reproductive phases identified macroscopically were significantly different than the corresponding phase identified microscopically. Gonadosomatic index values were elevated for both males and females from May-October, coinciding with elevated water temperatures. On average, a female Red Lionfish in the nGOM is capable of spawning every 2.49 days, 11 months out of the year. Mean batch fecundity was 26,904 eggs and mean relative batch fecundity was 92.2 eggs/g of gonad free body weight and peaked during the warmer months. From this information, an average size mature female of 188.6g is capable of producing 2,332,490 eggs/year. This study provides the most comprehensive description of invasive Red Lionfish reproduction, age and growth, to date, in the nGOM and will be used in creating management plans

Oldest Indo-Pacific Lionfish (Pterois volitans/P. miles) Recorded From the Northwestern Gulf of Mexico

Indo-Pacific lionfish (Pterois volitans/miles) were first detected off the coast of Florida in the 1980s, with aquaria release being the most likely mechanism for introduction. Since then, lionfish have proliferated through the Western Atlantic Ocean, Caribbean Sea, and Gulf of Mexico (GOM). Here, we report the oldest lionfish aged on record in the Western Atlantic, removed from Flower Garden Banks National Marine Sanctuary (FGBNMS) in the GOM. In August 2018, a research expedition removed 745 lionfish from FGBNMS, of which a subset were retained for age and growth estimation. The oldest lionfish was a 10 y old male, with total length 375 mm and weight 805 g. The back-calculated birth date (2008) preceded the first observation of lionfish at FGBNMS by 3 years (2011). It is not well understood if lionfish are having negative impacts at FGBNMS, but this report signifies the importance of continued monitoring and removal efforts of this protected area

Reproductive Life History Characteristics of Invasive Red Lionfish (\u3ci\u3ePterois volitans\u3c/i\u3e) In the Northern Gulf of Mexico

© 2017 Rosenstiel School of Marine & Atmospheric Science of the University of Miami.With invasive lionfish (Pterois spp.) increasing throughout the western North Atlantic Ocean and Gulf of Mexico (GOM), it is important to define life history characteristics to help understand the invasion and potential effects on receiving ecosystems. Although some aspects of reproduction are known elsewhere in the invaded range, little is known in the northern GOM [nGOM; Florida Keys (24.66°N) to south Texas (26.00°N)]. In the present study, gonadosomatic index (GSI) calculations were based on 4527 red lionfish Pterois volitans (Linnaeus, 1758) specimens (April 2012–March 2015). Male and female GSI peaked from May to October, corresponding with macroscopic gonadal assessments of reproductively active females. Histological examination of ovaries from 355 females found they were spawning capable during all months. Males (n = 211) were spawning capable in all months except March, the only month in which no actively spawning females were present. A significantly higher percentage of reproductively active females was found from May to December. Lionfish reached 50% maturity at a small size (166.6 mm TL, females; 145.2 mm TL, males). Mean relative batch fecundity (n = 71) was 92 eggs g–1 gonad-free body weight (GFBW) and was highest in August (207 eggs g–1 GFBW). The population spawning frequency was estimated to be every 2.5 d over 11 mo in the nGOM, corresponding to a maximum potential annual output of 2,332,490 eggs for an average sized (188.6 g) female. These reproductive characteristics are similar to invasive lionfish in tropical waters, although nGOM reproductive output appears higher. Our results represent the most comprehensive reproductive data on lionfish in their invaded range, and provide a baseline for management in the nGOM

Regional Genetic Structure and Genetic Founder Effects in the Invasive Lionfish: Comparing the Gulf of Mexico, Caribbean and North Atlantic

Indo-Pacific lionfish (Pterois volitans and P. miles) recently invaded Western Atlantic waters, rapidly spreading through the Caribbean and Gulf of Mexico (GoM). Previous genetic analyses using the mitochondrial d-loop determined that populations in the Western North Atlantic (NA) region have up to nine haplotypes, whereas Caribbean populations contain four of the North Atlantic haplotypes. The genetic composition of GoM populations, reported here for the first time, could lend insight into the pathway of dispersal into the GoM and better understanding of the biogeography of this recent invader. Here, we determined the genetic composition of lionfish throughout the GoM and compared haplotype composition to Caribbean and North Atlantic regions. We found that GoM samples contained only three d-loop haplotypes that are common in the Caribbean and North Atlantic. The genetic structure differed significantly among the three regions (AMOVA:Φ CT = 0.062; p = 0.001), but we found no differences between locations within regions (AMOVA:Φ SC = 0.005; p = 0.092). The composition of GoM samples most closely matches the composition of Caribbean samples indicating that Caribbean populations are the likely source of the GoM populations. As each region was successively invaded, a drop in haplotype diversity and changes in haplotype frequencies occurred indicating dispersal limitation across basin boundaries and founder effects within each basin. The lack of differentiation within regions indicates rapid population growth and unfettered dispersal within basins after initial colonization. We find no evidence of secondary invasions within samples. With well-established populations, the probability of detecting a secondary invasion is minuscule

Testing the efficacy of lionfish traps in the northern Gulf of Mexico.

Spearfishing is currently the primary approach for removing invasive lionfish (Pterois volitans/miles) to mitigate their impacts on western Atlantic marine ecosystems, but a substantial portion of lionfish spawning biomass is beyond the depth limits of SCUBA divers. Innovative technologies may offer a means to target deepwater populations and allow for the development of a lionfish trap fishery, but the removal efficiency and potential environmental impacts of lionfish traps have not been evaluated. We tested a collapsible, non-containment trap (the 'Gittings trap') near artificial reefs in the northern Gulf of Mexico. A total of 327 lionfish and 28 native fish (four were species protected with regulations) recruited (i.e., were observed within the trap footprint at the time of retrieval) to traps during 82 trap sets, catching 144 lionfish and 29 native fish (one more than recruited, indicating detection error). Lionfish recruitment was highest for single (versus paired) traps deployed 10X higher for lionfish than native fishes and that traps did not move on the bottom during two major storm events, although further testing will be necessary to test trap movement with surface floats. Additional research should also focus on design and operational modifications to improve Gittings trap deployment success (68% successfully opened on the seabed) and reduce lionfish escapement (56% escaped from traps upon retrieval). While removal efficiency for lionfish demonstrated by traps (12-24%) was far below that of spearfishing, Gittings traps appear suitable for future development and testing on deepwater natural reefs, which constitute >90% of the region's reef habitat

The Role of Citizen Science in the Research and Management of Invasive Lionfish across the Western Atlantic

Managing invasive Indo-Pacific lionfish (Pterois volitans and P. miles) in the Western Atlantic Ocean is beyond the capacity of natural resource organizations alone. In response, organizations have mobilized members of the public and citizen scientists to help. We used a structured survey to assess the activities and perceptions of 71 organizations that engage the public and citizen scientists in lionfish research and management throughout the invaded range of the Western Atlantic. Five case studies were also conducted that exemplified varied and multi-pronged approaches to engagement of the public and citizen scientists in lionfish control, monitoring, and knowledge-sharing. The public has been engaged to some extent in every approach, but organizations most frequently indicated engaging members of the public in raising awareness, promoting consumption, organized culling/removal, tournaments, and data collection. Sixty-five percent of organizations surveyed engaged the public in data collection, and data collection was ranked as the scientific research activity in which the public is most often involved. Most organizations indicated their data has contributed to scientific publications, management, and government agency research and/or policy. Collectively these findings demonstrate the conservation value of citizen scientists to assist organizational efforts to control, manage, and study a large-scale marine invasion