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Red snapper, Lutjanus campechanus, supports one of the more important fisheries in marine waters of the United States. Consequently, it has been the focus of intensive fisheries research for more than 20 years. Here, we present a genomic analysis of population structure that uses a landscape genetics approach to characterize patterns of variation in adult red snapper in the Gulf of Mexico (GOM) alongside a synoptic view of decades of stock-structure research. The results support Atlantic and GOM stocks and indicate weak heterogeneity within the GOM. Furthermore, redundancy analysis using Moran Eigenvector Maps based on physical distance, larval dispersal probability, and adult dispersal probability reveal heterogeneity on various spatial scales, with adult movement explaining a larger component of variation than spatial position or larval dispersal. Results of this study support the idea that red snapper in the GOM display metapopulation structure, but also suggest a potential genetic discontinuity along the West Florida Shelf not previously described. The approach of using landscape genomics and dispersal data (larval and/or adult) to better understand metapopulation dynamics is promising for not only red snapper, but also for other marine species that occupy a diversity of habitats and are seemingly distributed continuously.

We tested whether Δ14C values of eye lens protein (crystallin) formed in early life could be utilized to validate marine bony fish age estimates via the bomb radiocarbon chronometer. The slope of the relationship between red snapper (Lutjanus campechanus; n = 8; 0 to 27 years old), otolith and eye lens core Δ14C values was not significantly different than 1, which was also true for seven additional reef fish species (n = 21; 0 to 24 years old). Results demonstrate eye lens core Δ14C can be utilized to validate age estimates of marine fishes, which will be useful in numerous age validation applications.

Large-scale anthropogenic disturbances can have direct and indirect effects on marine communities, with direct effects often taking the form of widespread injury or mortality and indirect effects manifesting as changes in food web structure. Here, we report a time series that captures both direct and indirect effects of the Deepwater Horizon Oil Spill (DWH) on northern Gulf of Mexico (nGoM) reef fish communities. We observed significant changes in community structure immediately following the DWH, with a 38% decline in species richness and 26% decline in Shannon-Weiner diversity. Initial shifts were driven by widespread declines across a range of trophic guilds, with subsequent recovery unevenly distributed among guilds and taxa. For example, densities of small demersal invertivores, small demersal browsers, generalist carnivores, and piscivores remained persistently low with little indication of recovery seven years after the DWH. Initial declines among these guilds occurred prior to the arrival of the now-widespread, invasive lionfish (Pterois spp.), but their lack of recovery suggests lionfish predation may be affecting recovery. Factors affecting persistently low densities of generalist carnivores and piscivores are not well understood but warrant further study given the myriad ecosystem services provided by nGoM reef fishes.

Geopositioning underwater acoustic telemetry was used to test whether rapid recompression with weighted return-to-depth (descender) devices reduced discard mortality of red snapper (n = 141) and gray triggerfish (n = 26) captured and released at 30–60 m depths at two 15 km2 study sites in the northern Gulf of Mexico. Cox proportional hazards modelling indicated red snapper released with descender devices had significantly lower discard mortality within the first 2 d (95% CI = 18.8–41.8% for descender-released vs. 44.0–72.4% for surface-released, unvented fish), while there was no significant effect of descender devices on discard mortality of gray triggerfish. Predation by large pelagic predators was estimated to account 83% of red snapper and 100% of gray triggerfish discard mortality. Discard mortality due to predation has likely been overlooked in previous mark-recapture, laboratory, and enclosure studies, suggesting cryptic population losses due to predation on discards may be underestimated for red snapper and gray triggerfish. Large-area three-dimensional positioning acoustic telemetry arrays combined with collaboration and data sharing among acoustic telemetry researchers have the potential to advance our knowledge of the processes affecting discard mortality in reef fishes and other taxa.

We tested the efficacy of a stereo camera (SC) system adapted for use with a remotely operated vehicle (ROV) to estimate fish length distributions at reef sites in the northern Gulf of Mexico. A pool experiment was conducted to test the effect of distance (1, 2, 3 or 5 m), angle of incidence (AOI; 0° to 40° at 5° increments), and SC baseline distance (BD; BD1 = 406, BD2 = 610, and BD3 = 762 mm camera separation) on the accuracy and precision of fish model length (288, 552, or 890 mm fork length) estimates compared to a red laser scaler (RLS). A field experiment was then conducted at 20 reef sites with SCs positioned at BD1 to compare fish length distribution estimates between the SC and RLS systems under in situ conditions. In the pool experiment, mean percent errors were consistently within the a priori selected threshold of ±5% at AOIs ≤10° at all distances with all four systems. However, SCs produced accurate estimates at AOIs up to 30° at all distances tested; 2–3 m was optimal. During reef site surveys, SCs collected 10.4 times as many length estimates from 4.3 times as many species compared to the RLS. Study results demonstrate that, compared to laser scalers, ROV-based SC systems can substantially increase the number of available fish length estimates by producing accurate length estimates at a wider range of target orientations while also enabling measurements from a greater portion of the cameras’ field of view.

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

PURPOSE Lifirafenib is an investigational, reversible inhibitor of B-RAFV600E, wild-type A-RAF, B-RAF, C-RAF, and EGFR. This first-in-human, phase I, dose-escalation/dose-expansion study evaluated the safety, tolerability, and efficacy of lifirafenib in patients with B-RAF– or K-RAS/N-RAS–mutated solid tumors. METHODS During dose escalation, adult patients with histologically/cytologically confirmed advanced solid tumors received escalating doses of lifirafenib. Primary end points were safety/tolerability during dose escalation and objective response rate in preselected patients with B-RAF and K-RAS/N-RAS mutations during dose expansion. RESULTS The maximum tolerated dose was established as 40 mg/d; dose-limiting toxicities included reversible thrombocytopenia and nonhematologic toxicity. Across the entire study, the most common grade ≥ 3 treatment-emergent adverse events were hypertension (n = 23; 17.6%) and fatigue (n = 13; 9.9%). One patient with B-RAF–mutated melanoma achieved complete response, and 8 patients with B-RAF mutations had confirmed objective responses: B-RAFV600E/K melanoma (n = 5, including 1 patient treated with prior B-RAF/MEK inhibitor therapy), B-RAFV600E thyroid cancer/papillary thyroid cancer (PTC; n = 2), and B-RAFV600E low-grade serous ovarian cancer (LGSOC; n = 1). One patient with B-RAF–mutated non–small-cell lung cancer (NSCLC) had unconfirmed partial response (PR). Patients with K-RAS–mutated endometrial cancer and K-RAS codon 12–mutated NSCLC had confirmed PR (n = 1 each). No responses were seen in patients with K-RAS/N-RAS–mutated colorectal cancer (n = 20). CONCLUSION Lifirafenib is a novel inhibitor of key RAF family kinases and EGFR, with an acceptable risk-benefit profile and antitumor activity in patients with B-RAFV600–mutated solid tumors, including melanoma, PTC, and LGSOC, as well as K-RAS–mutated NSCLC and endometrial carcinoma. Future comparisons with first-generation B-RAF inhibitors and exploration of lifirafenib alone or as combination therapy in patients with selected RAS mutations who are resistant/refractory to first-generation B-RAF inhibitors are warranted.

Spearfishing is currently the primary approach for removing invasive Indo-Pacific lionfish (Pterois volitans/miles complex) to mitigate their impacts to western Atlantic marine ecosystems. However, a substantial portion of lionfish spawning biomass is beyond the depth limits of SCUBA. Innovative technologies may offer an alternative means to target lionfish and allow for the development of a deepwater lionfish trap fishery, but the removal efficiency and potential environmental impacts of 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 fishes (4 of which regulated species) recruited to traps (i.e., number of fish observed within the trap footprint) during 82 trap sets, catching 144 lionfish and 29 native species. Lionfish recruitment was highest for single (versus paired) traps deployed 10X higher for lionfish versus native fishes. Gittings traps did not move on the bottom during two major storm events; however, further testing will be necessary to test trap movement with surface buoys. 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 (12–24%) was far below that of spearfishing, study results demonstrate Gittings traps are suitable for future testing on deepwater natural reefs, which constitute >90% of the region’s reef habitat.

Radiocarbon (Δ14C) was analyzed in northern Gulf of Mexico (nGOM) red snapper (Lutjanus campechanus) otolith cores (n = 23), otolith edge samples (n = 12), and whole age-0 otoliths (n = 9), with edge samples and whole age-0 otoliths constituting known-age samples. There was no significant difference in the linear relationship of Δ14C versus year of formation between regional corals and known-age otolith samples, and a linear regression fit to the combined data from 1980 to 2015 extends the utility of the bomb radiocarbon chronometer for age validation. The entire regional coral and known-age otolith data set (1940 to 2015) was then utilized as a reference series to validate otolith-derived red snapper age estimates for cored otolith samples. A loess regression was fit to the reference data and then the sum of squared residuals (SSR) was computed from predicted versus observed birth years for cored adult otolith samples. This process was then repeated for ages biased ±1–4 years. Ages with no bias applied had the lowest SSR, thus validating red snapper age estimates and demonstrating the utility of the combined regional coral and known-age red snapper otolith Δ14C time series for age validation of nGOM marine fishes.

Key methodological assumptions regarding the degree of natural variability and influence of sample handling and storage of elasmobranch vertebral chemistry were assessed using laser-ablation inductively coupled plasma mass spectrometry. Vertebral chemistry of juvenile blacktip sharks Carcharhinus limbatus was examined to identify whether differences existed among different regions of the vertebral column, between thoracic vertebrae of individual fish or within individual vertebrae. Additionally, the effects of bleach exposure and storage in ethanol on vertebral chemistry were compared. No significant variation in vertebral chemistry was found among different regions of the vertebral column or between thoracic vertebrae, but significant differences among transect locations within individual vertebrae were observed. The variation at all three levels appears comparable with published data on sagittal otoliths of bilaterally symmetrical teleost fishes. The experimental assessment of potential treatment effects indicated vertebral chemistry was not significantly affected by bleach or exposure to ethanol. Taken together, these results support the idea that vertebrae taken from the same region of the vertebral column can be treated as equivalent and at least certain elements remain robust to exposure to bleach and ethanol.

Few data exist to evaluate the performance or assess the potential impacts of hook regulations on catchability or selectivity of recreational fisheries in the northern Gulf of Mexico. The purpose of this study was to test the effects of hook type (circle vs. J hook) and hook size (1/0, 4/0, and 7/0) on catch composition, traumatic hooking, species-specific catches, and size-selectivity of red snapper, Lutjanus campechanus, and grey triggerfish, Balistes capriscus. Selectivity was estimated by conditioning size distributions from hook-specific catches against in situ size distributions observed with a remotely operated vehicle. Deep hooking (hook set in gills or beyond) was low in all hook treatments for red snapper (

Instruments are often deployed at depth for weeks to years for a variety of marine applications. In many cases, divers can be deployed to retrieve instruments, but divers are constrained by depth limitations and safety concerns. Acoustic release technology can also be employed but can add considerable expense and acoustic releases will at times fail. Here, we report a simple method that utilizes a commercially available mooring hook integrated with a mini remotely operated vehicle to attach lines to instruments deployed on the sea floor, which can then be winched to the surface. The mooring hook apparatus was tested in a pool setting and then used to retrieve acoustic telemetry receiver bases (50 kg) or fish traps (30-50 kg) from the northern Gulf of Mexico continental shelf at depths between 28 and 80 m. During 2013-2019, 539 retrievals (100% success rate) were made of receiver bases (n = 239) and traps (n = 300) on 30 sea days using this approach. This method could easily be applied to other types of instruments, or recovery and salvage of objects that are too deep for standard diving operations.

Substantial declines in reef fishes were observed at northern Gulf of Mexico artificial reef sites between 2009�2010 and 2011�2012, a period that bracketed the appearance of invasive lionfish in this ecosystem. Small demersal reef fishes, the predominant prey of lionfish in other sys- tems, displayed the greatest declines. However, a confounding factor during this time was the Deepwater Horizon Oil Spill (DWH) in summer 2010. In some areas, targeted lionfish removals have been demonstrated to mitigate negative effects on native fishes. Therefore, we conducted a 2 yr experiment to examine the effectiveness and ecological benefits of targeted lionfish removals at artificial reefs (n = 27) off northwest Florida, USA, where lionfish densities reached the highest recorded in the western Atlantic by 2013. All lionfish were removed via spearfishing from 17 reefs in December 2013, 9 of which were periodically re-cleared of lionfish through May 2015. Remain- ing sites served as uncleared controls. Both juvenile and adult lionfish quickly recruited to cleared reefs, with lionfish reaching pre-clearance densities in

Recreational fishers discard millions of red snapper (Lutjanus campechanus) annually in the northern Gulf of Mexico (nGOM), resulting in significant foregone yield. We conducted simulation modeling to evaluate the potential for hook-size regulations to improve efficiency in the recreational red snapper fishery. First, we imposed a suite of candidate parameter sets, informed by recent empirical studies, within the 2015 red snapper assessment model to estimate contact-selectivity of recreational fleets in the northeastern or northwestern GOM. We then evaluated potential hook-size regulations by imposing a suite of candidate parameter sets on future contact-selectivity of each recreational fleet, conditional on likelihood-based estimates from the first simulation exercise. In the assessment model, maximum likelihood values improved when strongly domed contact-selectivity curves with peak size approximating the current minimum length limit were imposed in either the eastern or western recreational fleet. Simulation results indicate mandating large hook sizes could modestly increase retained catch for the eastern recreational fleet while dramatically reducing the number of red snapper discarded by either fleet. Realized benefits of hook-size regulations will depend upon future fisher retention behavior, such as the intensity of live high-grading, discard mortality reduction practices, such as venting and the use of descender devices, and changes to current management regulations.

Warsaw grouper, Hyporthodus nigritus, is a western Atlantic Ocean species typically found at depths between 55 and 525 m. It is listed as a species of concern by the U.S. National Marine Fisheries Service and as near threatened by the International Union for the Conservation of Nature. However, little information exists on the species' life history in the northern Gulf of Mexico (nGOM) and its stock status in that region is currently unknown. Age of nGOM Warsaw grouper was investigated via opaque zone counts in otolith thin sections (max age = 61 y), and then the bomb 14C chronometer was employed to validate the accuracy of age estimates. Otolith cores (n = 14) were analyzed with accelerator mass spectrometry and resulting Δ14C values overlain on a loess regression computed for a regional coral and known-age red snapper Δ14C time series. Residual analysis between predicted Δ14C values from the loess regression versus Warsaw grouper otolith core Δ14C values indicated no significant difference in the two data series. Therefore, the accuracy of otolith-based aging was validated, which enabled growth and longevity estimates to be made for nGOM Warsaw grouper. Dissolved inorganic carbon (DIC) Δ14C values collected from the nGOM support the inference that juvenile Warsaw grouper occur in shelf waters (

An emerging ulcerative skin disease in invasive lionfish in Florida and Caribbean Sea is being tracked. Diseased lionfish were first reported in summer 2017 from the northern Gulf of Mexico with additional reports in 2018. Florida Fish and Wildlife Conservation Commission, University of Florida, and other fish health scientists are investigating this disease, but initial evaluations have not yet identified a cause. More advanced diagnostics are underway to better understand the factors causing this disease/syndrome and its potential to spread to other species. Researchers are also examining the lethal and chronic effects of this disease on individual fish, as well as its effect on lionfish populations, the lionfish fishery, and reef fish communities. Researchers and Extension Personnel (IFAS/SeaGrant) are asking stakeholders to report and document any ulcerated or otherwise diseased lionfish in FL and the Caribbean.

Otolith chemical signatures of Red Snapper Lutjanus campechanus from six nursery regions were used to estimate the sources of recruits to four sampling regions in the western Gulf of Mexico (Gulf) and to estimate whether postsettlement mixing of Red Snapper occurs between the U.S. and Mexican portions of the western Gulf. In a previous study, region-specific otolith signatures (element : Ca ratios: Ba:Ca, Mg:Ca, Mn:Ca, Sr:Ca, and Li:Ca; stable isotope delta values: δ13C and δ18O) were developed based on age-0 Red Snapper (2005–2007 year-classes) sampled from the six nursery areas. In the present study, subadult and adult Red Snapper (ages 1–3) belonging to those same year-classes were collected from four sampling regions within the western Gulf (two regions in U.S. waters; two regions along the Mexican continental shelf) during summer in 2006–2008. Left sagittal otoliths were used to age subadults and adults to the corresponding nursery year-classes, and right sagittal otoliths were cored for chem...

Red Snapper Lutjanus campechanus were sampled at 33 natural and 27 artificial reef sites in the northern Gulf of Mexico prior to (2009–2010) and after (2010–2011) to examine potential diet and trophic shifts following the Deepwater Horizon (DWH) oil spill. We dissected 708 stomachs for gut content analysis and processed 65 muscle tissue samples for stable isotope ratio-mass spectrometry analysis of δ13C, δ15N, and δ34S. Forty-eight percent of stomachs contained identifiable prey, which we grouped into seven categories: fish, decapods, cephalopods, stomatopods, gastropods, zooplankton, and other invertebrates. Based on these categories, Red Snapper diet was significantly different following the DWH oil spill, and was differentially affected by fish size. The interaction between habitat (natural versus artificial reefs) and DWH oil spill effects was also significant. Significant differences in diet among Red Snapper size-classes were due to low trophic position prey, such as pelagic zooplankton, bei...

The objective of this study was to evaluate whether age-0 lane snapper Lutjanus synagris otolith chemical signatures could serve as accurate proxies for those of its congener, red snapper L. campechanus, among northern Gulf of Mexico (GOM) nursery regions. Red (n = 90) and lane (n = 53) snappers were sampled from 3 regions of the northern GOM in fall 2005, and their otolith chemistry was analyzed with sector field-inductively coupled plasma-mass spectrom- etry (Ba:Ca, Mg:Ca, Mn:Ca, Sr:Ca, Li:Ca) or stable isotope ratio-mass spectrometry (δ 13 C and δ 18 O). Chemical signatures were significantly different among regions (MANOVA, p < 0.001) and between species (MANOVA, p = 0.029), with the species effect being driven by significant differ- ences in 4 of the 7 constituents analyzed (ANOVA, p < 0.036). The significant region effect per- sisted (MANOVA, p < 0.001), but the species effect was non-significant (MANOVA, p = 0.964) when constituent values were normalized to species-specific means. Mean regional classification accuracies from linear discriminant functions computed with otolith constituent data were 84% for lane snapper and 80% for red snapper whether data were normalized or not. Maximum likelihood models parameterized with normalized lane snapper otolith chemistry data estimated red snapper regional composition reasonably well among mixed-region samples (mean error = 9.7% among models). Therefore, it appears age-0 lane snapper otolith chemical signatures can serve as accu- rate proxies for those of red snapper in the northern GOM. These results have broader implica- tions for deriving natural tags based on otolith chemistry for fishes that may have low abundance in parts of their range.

Circle hooks are required when targeting reef fishes in the U.S. federal waters of the Gulf of Mexico. However, limited data is available to evaluate circle hook performance (e.g., hooking location and catch rate) or selectivity in this fishery. Therefore, a fishing experiment was conducted to test the performance of a range of circle hook sizes (2/0 and 4/0 Mustad 39940BLN and 9/0, 12/0, and 15/0 Mustad 39960D) in the recreational reef fish fishery, as well as to estimate hook selectivity directly for Red Snapper Lutjanus campechanus, the most targeted reef fish in the northern Gulf of Mexico. Reef fish communities were surveyed with a micro remotely operated vehicle equipped with a laser scaler and then fished with one of five circle hook sizes. Hooking location typically was in the jaw for all hooks examined, with the mean percentage of jaw hooking being 94.1% for all reef fishes and 92.9% for Red Snapper. Fish size generally increased with hook size but at the cost of a reduced catch rate. The...

Background The microbiota plays an essential role in host health, particularly through competition with opportunistic pathogens. Changes in total bacterial load and microbiota structure can indicate early stages of disease, and information on the composition of bacterial communities is essential to understanding fish health. Although Red Snapper (Lutjanus campechanus) is an economically important species in recreational fisheries and a primary aquaculture candidate, no information is available on the microbial communities of this species. The aim of this study was to survey the microbiota of apparently healthy, wild-caught Red Snapper from the Gulf of Mexico. Sampled Red Snapper showed no physical signs of disease. Tissues that are either primary entry routes for pathogens (feces, gill) or essential to disease diagnosis (blood) were sampled. Bacteria were enumerated using culture-based techniques and characterized by pyrosequencing. Results Aerobic counts of feces and gill samples were 107 and 104 CFU g-1, respectively. All individuals had positive blood cultures with counts up to 23 CFU g-1. Gammaproteobacteria dominated the microbiota of all sample types, including the genera Pseudoalteromonas and Photobacterium in feces and Pseudomonas in blood and gill. Gill samples were also dominated by Vibrio while blood samples had high abundances of Nevskia. High variability in microbiota composition was observed between individuals, with percent differences in community composition ranging from 6 to 76 % in feces, 10 to 58 % in gill, and 52 to 64 % in blood. Conclusions This study provides the first characterization of the microbiota of the economically significant Red Snapper via pyrosequencing. Its role in fish health highlights the importance of understanding microbiota composition for future work on disease prevention using microbial manipulation.

The effect of circle hook size on reef fish catch rates, species composition, and selectivity was tested in the northern Gulf of Mexico recreational fishery. Fish communities first were sampled at natural (n = 19) and artificial (n = 23) reefs with a micro remotely operated vehicle (ROV) equipped with a laser scale. Fishing experiments (n = 69) then were conducted with 9/0, 12/0, and 15/0 circle hooks. Hook size significantly affected fish catch rates, species composition, and size. Small invertivore fishes constituted 33.4% of the catch taken with 9/0 hooks, but were nearly absent from the catch made with larger hook sizes. In contrast, red snapper, Lutjanus campechanus (Poey, 1860), constituted only 25.3% of fishery species total abundance in video samples, but ranged from 59.1% of the 9/0 hook catch to nearly 90% for 15/0 hooks. A novel maximum likelihood approach was developed to estimate exponential-logistic selectivity functions for each hook size from ROV-based estimates of red snapper size distributions and observed hook-specific catch at size. Both the 9/0 and 12/0 hooks displayed dome-shaped selectivity functions, while the 15/0 hook size was estimated to have a logistic-shaped function. However, observed catch-at-size data displayed a dome-shaped pattern for 15/0 catches when paired with 9/0 hooks, but an indistinct pattern when paired with 12/0 hooks. Overall, study results suggest that regulating circle hook size would affect reef fish catch rates and size in the northern Gulf of Mexico recreational fishery, but potential conservation benefits may be confounded by unintended effects.

Fish community and trophic structure were examined quarterly from fall 2004 through spring 2007 at 27 artificial reef sites located 15-20 mi south of Pensacola, Florida. Location of study sites was not reported to the public when reef modules were deployed in 2003, thus sites were presumed to be unfished. Community structure estimates were derived from video sampling that was performed with a micro remotely operated vehicle (ROV) equipped with a laser scale to estimate fish size. A total of 81,207 individuals from 77 different taxa was enumerated from video samples. Fish assemblages were dynamic in species richness, fish community structure, and trophic structure across time and by reef design. Total fish density, biomass, and species richness increased across time. Red snapper, Lutjanus campechanus (Poey, 1860), was by far the most abundant species (29% of individuals, 45% of total biomass), and its density and biomass increased over the course of the study. Differences in fish community structure were driven by sharp declines in grouper abundance and the proliferation of smaller fishes across time. Trophic structure was consistently dominated by invertivore/piscivores, while fluctuation in piscivore biomass and increased abundance of planktivores drove differences in trophic structure. Size distributions for many fishery species known to display low annual site fidelity were composed primarily of young, sub-legal individuals. Disappearance with increasing fish size was likely due to shifting ontogenetic habitat requirements or exposure to high regional fishing mortality for species that displayed low annual site fidelity to study sites.

In the original publication, the Acknowledgements section has been published incorrectly. The corrected Acknowledgements is given in this correction

The Atlantic Ocean and Gulf of Mexico (GOM) stocks of king mackerel Scomberomorus cavalla are genetically distinct but have overlapping winter ranges around South Florida. Understanding the factors driving the relative contribution of each stock to South Florida winter landings is necessary for effective management. The contribution of the Atlantic stock was estimated for the 2006–2007 and 2007–2008 fishing seasons using otolith shape as a natural tag. Analysis of otolith shapes from king mackerel sampled in summer (when the Atlantic and GOM stocks were presumed to be geographically separated) revealed significant sex and stock effects. Discriminant function analysis conducted with otolith morphometric indices and Fourier harmonic amplitudes as classification variables produced jackknifed classification success rates ranging from 60% to 73%. Maximum likelihood estimates of the Atlantic stock's contribution to winter landings indicated that there was a spatial gradient, the lowest contribution (me...

Wells, R. J. D., James H. Cowan Jr, and William F. Patterson III. 2008. Habitat use and the effect of shrimp trawling on fish and invertebrate communities over the northern Gulf of Mexico continental shelf. – ICES Journal of Marine Science, 65: 1610–1619. The goals of this study were to characterize habitat-specific fish and invertebrate community structure over sand, shell-rubble, and natural reef substrata, and to assess the effects of trawling on the sand and shell-rubble habitats and their associated communities during quarterly trawl surveys over a 2-year period. Fish and invertebrate communities differed significantly among habitat types [analysis of similarities (ANOSIM); Global R = 0.436, p < 0.001), and with respect to trawling exposure (ANOSIM; Global R = 0.128, p < 0.001). Habitat characteristics were quantified from video transects sampled with a remotely operated vehicle, and included percentage coverage of tubeworms, bryozoans, anemones, corals, and algae, significantly affecting fish community structure. Diversity indices differed among habitats, with the highest Shannon diversity (H′) and Pielou's evenness (J′) over shell-rubble, specifically non-trawled shell-rubble. In addition, higher values of H′ and J′ were found over trawled sand relative to non-trawled sand habitats. Length frequency distributions of several abundant fish species showed truncated size distributions over trawled and non-trawled habitats and were both habitat- and species-specific. The study describes habitat-specific differences in community structure, highlighting the differences between trawled and non-trawled areas on the northern Gulf of Mexico continental shelf.

Background: BGB-283 is a novel inhibitor of the RAF dimer with potent and reversible inhibitory activities against RAF family kinases including wild type A-RAF, B-RAF, C-RAF and B-RAF V600E, as well as EGFR. BGB-283 demonstrated acceptable safety and early clinical activity in its Phase 1A study. In this Phase IB dose expansion study, we further evaluated safety and tolerability of BGB-283 and investigated efficacy in pre-selected patients (pts) with B-RAF or K-RAS/N-RAS-mutated solid tumors. Methods: This Phase 1B study was a multicenter, open-label, multiple-arm, dose expansion study. Pts were treated at the RP2D of BGB-283 at 30 mg/day. There were 10 different expansion arms for: B-RAF V600-mutated melanoma (not previously treated with a B-RAF or MEK inhibitor, and B-RAF and/or MEK inhibitor-resistant pts), colorectal cancer (CRC), non-small cell lung cancer (NSCLC), papillary thyroid cancer (PTC) and other solid tumors with B-RAF mutations; K-RAS/N-RAS-mutated endometrial cancer, NSCLC, CRC, and other solid tumors with K-RAS/N-RAS or NF-1 mutations. The primary end point was the response rate based on RECIST Version 1.1. Adverse events (AEs) are reported per CTCAE V4.03. Results: As of 19th Sep 2016, 96 pts were enrolled: median age was 63 years (range: 20 to 82 years) with all pts having baseline ECOG PS of 0 or 1. Forty-seven (49.0%) subjects had received ≥3 prior lines of treatment, 22 (22.9%) had received 2 prior lines of treatment, and 18 (18.8%) had received 1 prior line of treatment. BGB-283 was generally well-tolerated. Drug-related AEs were mostly Grade 1/2 in severity; the most common were fatigue in 37 (38.5%) subjects, nausea in 16 (16.7%), decreased appetite in 21 (21.9%), and diarrhea in 17 (17.7%). A total of 34 (35.4%) subjects experienced study drug-related Grade 3/4 AEs, notably drug-related thrombocytopenia (6.3%), palmar-plantar erythrodysesthesia syndrome (1.0%) and hypertension (8.3%). In the cohorts with previously-untreated B-RAF V600-mutated melanoma (n=7), PTC with B-RAF mutation (n=3) and NSCLC with K-RAS mutation (n=6), the response rates were 42.9% (95% confidence interval [CI], 9.9, 81.6), 33.3% (95% CI, 0.8, 90.6) and 16.7% (95% [0.4, 64.1]), respectively. Confirmed PR was seen in the single case of ovarian cancer with B-RAF mutation enrolled and also in one of 4 melanoma subjects with a confirmed B-RAF V600 mutation, who had not responded to B-RAF and/or MEK inhibitor(s). One unconfirmed PR was found in two NSCLC subjects with a B-RAF mutation. Conclusions: BGB-283 was generally well-tolerated during the Phase 1B stage of the study. Antitumor activity was not only observed in subjects with B-RAF V600-mutated solid tumors including melanoma, PTC, and ovarian cancer, but also in subjects with K-RAS-mutated NSCLC. When added to the efficacy data in the Phase IA portion of this study, with objective responses noted in these tumor subtypes as well as in K-RAS-mutated endometrial carcinoma, BGB-283 demonstrated a desirable risk-benefit profile for further efficacy and safety investigation. Citation Format: Jayesh Desai, Hui Gan, Catherine Barrow, Michael B. Jameson, Ben Solomon, Victoria Atkinson, Andrew Haydon, Michael Millward, Stephen Begbie, Michael Brown, Benjamin Markman, William Patterson, Andrew Hill, Lisa Horvath, Adnan Nagrial, Gary Richardson, Christopher Jackson, Michael Friedlander, David Gibbs, Phillip Parente, Jason Yang, Lai Wang, Yunxin Chen, Lusong Luo. A Phase IB study of RAF dimer inhibitor BGB-283 in patients with B-RAF or K-RAS/N-RAS mutated solid tumors [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr CT002. doi:10.1158/1538-7445.AM2017-CT002

Identifying and protecting shark nurseries is a common management strategy used to help rebuild overfished stocks, yet we know little about connectivity between juvenile and adult populations. By analysing trace metals incorporated into vertebral cartilage, it may be possible to infer natal origin based on nursery-specific chemical signatures. To assess the efficacy of this approach, we collected juvenile blacktip sharks (Carcharhinus limbatus; n = 93) from four regions in the Gulf of Mexico in 2012 and 2013 and analysed their vertebral centra with laser ablation–inductively coupled plasma–mass spectrometry. We observed significant regional differences in six element:Ca ratios in both 2012 and 2013. Multi-element chemical signatures were significantly different among regions and between year-classes. Year-class-specific linear discriminant function analysis yielded regional classification accuracies of 81% for 2012 and 85% for 2013, although samples were not obtained from all four regions in 2012. Combining year-classes resulted in an overall classification accuracy of 84%, thus demonstrating the usefulness of this approach. These results are encouraging yet highlight a need for more research to better evaluate the efficacy of vertebral chemistry to study elasmobranch population connectivity.

Otolith chemical signatures were used to estimate the number of likely nursery sources that contributed recruits to a suite of red snapper (Lutjanus campechanus) year-classes sampled in 2012 in US Atlantic Ocean waters from southern Florida (28°N) to North Carolina (34°N). Otoliths from subadult and adult fish (n=139; ages 2–5 years) were cored and their chemical constituents analysed for δ13C, δ18O, as well as the elemental ratios of Ba:Ca, Mg:Ca, Mn:Ca and Sr:Ca. Results from multiple linear regression analyses indicated that there was significant latitudinal variation for δ13C, Ba:Ca, Mg:Ca and Mn:Ca. Therefore, these variables were used to parameterise Markov Chain Monte Carlo (MCMC) models computed to estimate the most likely number of nursery sources to each age class. Results from MCMC models indicated that between two and seven nursery sources were equally plausible among the four age classes examined, but the likely number of nursery sources declined for fish aged 4 and 5 years because of apparent mixing between more northern and more southern signatures. Overall, there is evidence to reject the null hypothesis that a single nursery source contributed recruits among the age classes examined, but increased sample size from a broader geographic range may be required to refine estimates of the likely number of nursery sources.