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The behavior of fish around bait is poorly understood despite it being important for the fish catching process and estimating relative abundance. We used a fine-scale acoustic positioning system to quantify the movements of 26 red snapper (Lutjanus campechanus) around 120 bait deployments in 2019 at a natural reef site (∼37-m deep) in North Carolina, USA. There were 39 instances of tagged red snapper approaching bait during four baiting days, some of which approached due to apparent sensory cues (28%), while most approached incidentally (72%). Tagged red snapper approached bait from initial distances of 1 to 1147 m (median = 27 m; mean = 86 m), and took 0–77 min (mean = 22 min) to approach. Fish were more likely to approach bait if they were located close to, and down-current of, the bait at deployment. Our estimated effective fishing area of 2290 m2 (within which >50% of red snapper responded to bait) could be used along with video counts and other information to estimate densities of red snapper.

Acute morbidity and mortality of marlins (family Istiophoridae) in hook-and-line fisheries have been studied; however, there has been little or no investigation of the skeletal injuries incurred from terminal tackles that could lead to decreased rates of postrelease survival. The objective of this study was to evaluate skeletal injuries in recreationally angled Atlantic Blue Marlin Makaira nigricans from the 2019 Big Rock Blue Marlin Tournament in Morehead City, North Carolina. We examined heads of six Blue Marlin that were angled using artificial lures rigged with J-hooks and harvested for weigh-in. The head of each Blue Marlin was scanned using computed tomography (CT) and examined with gross dissection. The CT interpretation revealed that two Blue Marlin had minimally displaced fractures of the maxilla, one of which also had a fracture to the lachrymal bone. These radiographic lesions were associated with penetrating hook injuries. The CT images also revealed degenerative changes within the quadrate-articular joint in four Blue Marlin, which was associated with fish weight; the causes and consequences of these degenerative changes are unknown. Although the hooking-related jaw fractures likely result in acute pain, their impact on postrelease morbidity is unknown and the impact on postrelease mortality is suspected to be small.

Most demersal fishes are difficult to observe and track due to methodological and analytical constraints. We used an acoustic positioning system to elucidate the horizontal and vertical movements of 44 red snapper (Lutjanus campechanus) off North Carolina, USA, in 2019. Mean movement rate and distance off bottom varied by individual, with larger red snapper generally moving faster and spending more time farther off the bottom than smaller individuals. We used generalized additive mixed models that accounted for temporal autocorrelation in the data to show that mean hourly red snapper movement rate was lower during the day than at night and was negatively related to bottom water temperature. Moreover, red snapper spent more time off the bottom during the day than at night, and vertical movements were mostly related to bottom upwelling events that sporadically occurred in May–July. Our results and previous observations suggest that red snapper feed primarily on benthic organisms at night, and display diel vertical migration (i.e., thermotaxis) up to warmer waters (when present) during the day to aid digestive efficiency. Movement is a central organizing feature in ecology, and the sustainable management of fish will benefit from a better understanding of the timing and causes of fish movement.

In some fisheries, releases are a high percentage of total catch. Recent tagging data of marine fishes have revealed that recapture of the same individual multiple times occurs frequently. We investigated the magnitude of this phenomenon and its effect on survival using previously collected mark-recapture data of four reef-associated species. We used Cox proportional hazard regression models to examine whether survival varied with release number. For three of four species, survival was significantly higher after the second, third, and/or fourth release as compared to the first release, perhaps resulting from selection for robust individuals. Repetitive recapture implies that the estimated number of unique released fish is biased. Increased survival following later releases as compared to the initial release suggests that the number of dead discards may be similarly overestimated. We analysed the sensitivity of stock assessment results to reduced estimates of dead discards using two of our species that had recently been assessed. We found that reduced estimates of dead discards had a modest effect on assessment results but could nonetheless affect the perception of fishery status. Our findings highlight the need to revise current practices for estimating live and dead discards, either internal or external to stock assessment models.

Marine protected areas (MPAs) are increasingly used to rebuild fish populations. In 2009, eight MPAs were designated off the southeast United States with the goal of rebuilding populations of long-lived deep-water reef fishes. We tested whether reef fish within the largest of these MPAs, the Snowy Wreck Marine Protected Area (SWMPA), have increased in size and abundance relative to a nearby control area and compared to pre-closure. Hurdle models fitted through Bayesian inference on echosounder data collected in 2007–2009 and 2018–2020 yielded no evidence of an MPA effect. Comparisons of catch-per-unit-effort (CPUE) of all reef fishes yielded similar null results. However, CPUE of reef species with formal stock assessments increased 47% in the SWMPA and decreased 50% in the control area. We found significant increases in mean length of red porgy (Pagrus pagrus) inside the SWMPA but not in the control area. We also found community composition changes, including shifts away from groupers (Serranidae; Epinephelinae) and toward snappers (Lutjanidae) and tilefish (Malacanthidae) in both areas, though we did not detect an MPA effect with this analysis. Our equivocal results indicate that more time and stricter enforcement may be necessary before more biological effects of the SWMPA can be detected.

External attachment of electronic tags has been increasingly used in fish studies. Many researchers have used ad hoc attachment methods and provided little or no validation for the assumption that tagging itself does not bias animal behaviour or survival. The authors compared six previously published methods for externally attaching acoustic transmitters to fish in a tank holding experiment with black sea bass Centropristis striata (L.). They tracked tag retention, fish growth and external trauma (as a measure of fish welfare) for 60 days. For each of these metrics, the results showed a wide range of responses among tagging treatments. A simple attachment method using a spaghetti tag passed through the dorsal musculature of the fish and tied to the end cap of the transmitter emerged as the preferred option based on high retention, no impact on growth and relatively low detriment to fish welfare. Future field studies using external electronic tagging should consider tag-related effects that could compromise results when selecting a method for tag attachment.

Estimates of animal abundance are widely used to support conservation and resource management. For populations in open systems, abundance estimates from tagging data can be highly uncertain or biased. Here, we develop a novel approach to estimate abundance of an open population by pairing two models, each utilizing distinct tagging data. Using data from telemetry tags, we infer movement rates to and from the study site with a Markovian model allowing for an environmental effect. Then, using data from conventional passive tags, we apply a Lincoln–Petersen abundance estimator modified to account for mortality and movement. After developing the model within a Bayesian framework, we demonstrate its application to data on gray triggerfish (Balistes capriscus) tagged in the Atlantic Ocean off North Carolina, USA. For this open population, we estimate site abundance to be ∼1000 fish (∼2000 fish·km–2) and additionally find evidence for an effect of hurricanes on movement. The general approach may be useful for fisheries, wildlife, and other ecological studies utilizing multiple tag types, particularly for estimating abundance of an open population.

Funding for this work was provided by the NOAA Saltonstall-Kennedy Program (#NA17NMF4270204). Fate assignment is crucial to the results of survival studies, particularly those that utilize acoustic tagging. Most current methodologies are at least partially subjective; thus, having a means of objectively assigning fates would improve the precision, accuracy, and utility of such studies. We released 57 acoustically tagged fish belonging to six deepwater grouper species off North Carolina, USA, via surface release and recompressed release with descender devices. We applied a three‐state hidden Markov model (HMM) in a novel way: to distinguish movement patterns between fish that were alive and fish that were dead (and might have been eaten by predators). We assigned fates using two approaches that differed in their reliance on HMMs. When HMMs were the predominant source of fate assignment, we estimated survival of 40 deepwater groupers released with descender devices at the continental shelf break (66–120‐m depth) to be 0.46 (95% CI = 0.33–0.65). When a combination of HMMs and prior information was utilized, we estimated survival of the same 40 groupers to be 0.61 (95% CI = 0.47–0.80). Both estimates represented a substantial improvement over the survival of surface‐released groupers (n = 9; survival ~0.0). Furthermore, HMMs estimated zero survival for an additional five descended groupers at a wreck site in 240‐m depth, although one analysis using prior information suggested that survival was possible in that depth. These estimates were aided by the objectivity of HMMs, and we recommend that future survival studies involving acoustic tagging employ similar methodologies. The improved survival of groupers after descending is an important finding for management, as this taxon contains several species of impaired stock status or fishery status. Postprint

Selecting a target journal is a universal decision faced by authors of scientific papers. Components of the decision, including expected turnaround time, journal acceptance rate, and journal impact factor, vary in terms of accessibility. In this study, I collated recent turnaround times and impact factors for 82 journals that publish papers in the field of fisheries sciences. In addition, I gathered acceptance rates for the same journals when possible. Findings indicated clear among-journal differences in turnaround time, with median times-to-publication ranging from 79 to 323 days. There was no clear correlation between turnaround time and acceptance rate nor between turnaround time and impact factor; however, acceptance rate and impact factor were negatively correlated. I found no field-wide differences in turnaround time since the beginning of the COVID-19 pandemic, though some individual journals took significantly longer or significantly shorter to publish during the pandemic. Depending on their priorities, authors choosing a target journal should use the results of this study as guidance toward a more informed decision.

International audience; Phylogeographic studies inform about routes of pathogen dissemination and are instrumental for improving import/export controls. Genomes of seventeen isolates of the bacterial wilt and potato brown rot pathogen Ralstonia solanacearum race 3 biovar 2 (R3bv2), a select agent in the USA, were thus analyzed to get insight into the phylogeography of this pathogen. Thirteen of fourteen isolates from Europe, Africa, and Asia were found to belong to a single clonal lineage while isolates from South America were genetically diverse and carried ancestral alleles at the analyzed genomic loci consistent with a South American origin of R3bv2. The R3bv2 isolates share a core repertoire of thirty-one type III-secreted effector genes representing excellent candidates to be targeted with resistance genes in breeding programs to develop durable disease resistance. Towards this goal, 27 R3bv2 effectors were tested in eggplant, tomato, pepper, tobacco, and lettuce for induction of a hypersensitive-like response indicative of recognition by cognate resistance receptors. Fifteen effectors, eight of them core effectors, triggered a response in one or more plant species. These genotypes may harbor resistance genes that could be identified and mapped, cloned and expressed in tomato or potato, for which sources of genetic resistance to R3bv2 are extremely limited.

Summary The apparent lack of durability of many resistance (R) genes highlights the need for the constant identification of new genetic sources of resistance for the breeding of new disease-resistant crop cultivars. To this end, we screened a collection of accessions of eggplant and close relatives for resistance against Pseudomonas syringae pv. tomato (Pto) and Xanthomonas euvesicatoria (Xeu), foliar plant pathogens of many solanaceous crops. Both pathogens caused substantial disease on most genotypes of eggplant and its relatives. Promisingly, however, some of the genotypes were fully or partially resistant to either of the pathogens, suggesting the presence of effective resistance determinants in these genotypes. Segregation of resistance to the growth of Xeu following infiltration in F2 progeny from a cross of a resistant and susceptible genotype suggests that resistance to Xeu is inherited as a multigenic trait. With regard to Pto, a mutant strain lacking all 28 functional type III secreted effectors, and a Pseudomonas fluorescens strain expressing a P. syringae type III secretion system (T3SS), both elicit a strong cell death response on most eggplant lines. Several genotypes thus appear to harbour a mechanism for the direct recognition of a component of the T3SS. Therefore, eggplant and its close relatives are promising resources to unravel novel aspects of plant immunity and to identify new candidate R genes that could be employed in other Solanaceae in which Xeu and Pto cause agriculturally relevant diseases.

We estimated condition-specific survival rates of gray triggerfish (Balistes capriscus) using a tag-recapture approach and extrapolated these values to produce an overall discard survival estimate for the US South Atlantic recreational hook-and-line fishery. Tag return rates of fish tagged at the seafloor using SCUBA served as a reference for return rates of fish tagged at the surface. We examined the validity of gross necropsy as a proxy for survival by identifying likely causes of discard mortality. Best-condition surface-released fish (no external trauma) had an estimated mean proportional survival of 0.39 (95% confidence interval 0.28, 0.55). For gray triggerfish exhibiting visible trauma, estimated survival was 0.24 (0.10, 0.60). Floating fish had a survival rate of zero. The necropsy-based estimate of gray triggerfish lacking organ displacement closely matched the tag-based estimate of survival. Mean estimated discard survival across all depths for North Carolina was 0.35 (0.10, 0.59) and for Florida was 0.34 (0.08, 0.59). These results have implications for gray triggerfish management because our estimate of discard survival is substantially lower than previously assumed and for future discard survival research given our findings with gross necropsies.

The majority of bacterial foliar plant pathogens must invade the apoplast of host plants through points of ingress, such as stomata or wounds, to replicate to high population density and cause disease. How pathogens navigate plant surfaces to locate invasion sites remains poorly understood. Many bacteria use chemical-directed regulation of flagellar rotation, a process known as chemotaxis, to move towards favorable environmental conditions. Chemotactic sensing of the plant surface is a potential mechanism through which foliar plant pathogens home in on wounds or stomata, but chemotactic systems in foliar plant pathogens are not well characterized. Comparative genomics of the plant pathogen Pseudomonas syringae pathovar tomato (Pto) implicated annotated chemotaxis genes in the recent adaptations of one Pto lineage. We therefore characterized the chemosensory system of Pto. The Pto genome contains two primary chemotaxis gene clusters, che1 and che2. The che2 cluster is flanked by flagellar biosynthesis genes and similar to the canonical chemotaxis gene clusters of other bacteria based on sequence and synteny. Disruption of the primary phosphorelay kinase gene of the che2 cluster, cheA2, eliminated all swimming and surface motility at 21oC but not 28oC for Pto. The che1 cluster is located next to Type IV pili biosynthesis genes but disruption of cheA1 has no observable effect on twitching motility for Pto. Disruption of cheA2 also alters in planta fitness of the pathogen with strains lacking functional cheA2 being less fit in host plants but more fit in a non-host interaction.