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Development of Florida's marine Fisheries-Independent Monitoring (FIM) program began in 1985, and it initiated long-term monitoring in Tampa Bay in 1989 with the purpose of providing timely fishery-independent data and analyses to fishery managers for the conservation and protection of the species that support Florida's fisheries. Over time, the program expanded sampling in other Florida estuaries. Data from this monitoring program are integral to the assessment and management of numerous state and federally managed fishes, so long-term consistency is of paramount importance, but sampling design modifications have been necessary over time. This review presents three case studies in which the estuarine component of the FIM program was changed to address emerging data needs in management of Florida's fishery resources, while maintaining standardization and consistency with long-term surveys statewide. In the first case study, survey changes increased the amount of data on juvenile common snook, Centropomus undecimalis, on the Gulf of Mexico and Atlantic coasts and improved indices of abundance, survival estimates, and age-length keys for state management purposes. In the second case study, the FIM program improved estimates of abundance of juvenile reef fishes by initiating a complementary survey that expanded FIM sampling to new regions of the Florida Gulf coast and targeted a unique habitat (polyhaline seagrass beds along estuarine shoal habitats) not previously sampled in the standard longterm survey. In the third case study, the FIM program addressed a data limitation for regional management of spotted seatrout, Cynoscion nebulosus, by initiating seasonal sampling in western Florida. In each case study, the standard long-term survey design was modified to include sampling of new and unique areas and habitats, providing valuable data on estuarine fish assemblages that support analyses at the broader, ecosystem level. Survey amendments were designed to maintain standardization and consistency, all with limited additional funding. The success of these survey modifications was the result of several key factors: mission-focused programmatic goals, geographically dispersed laboratories, standardized protocols, ongoing critical analysis of the data, grant award success, and high-level data management. Although each case study originated with a survey expansion, all were followed by survey reductions or streamlining, so expansion and reduction scenarios are presented in this review. Regardless of these modifications, the mission of the FIM program remains the same: to provide timely data and analysis for the use of fishery managers, including state and federal partners. [ABSTRACT FROM AUTHOR]

In the southeastern USA and the Gulf of Mexico (GOM), Atlantic Tripletail Lobotes surinamensis are increasingly targeted by recreational anglers, indicating that stock status should be assessed. A critical need for such assessments is age-specific data; however, previous studies have drawn conflicting conclusions regarding the most appropriate structure for aging. Moreover, growth parameters and mortality rates for GOM Atlantic Tripletail are unknown. Therefore, the goals of this study were to (1) evaluate sagittal otoliths and first dorsal spines as aging structures; (2) model combined and sex-specific growth; and (3) estimate mortality rates for GOM Atlantic Tripletail. From 2012 to 2019, Atlantic Tripletail (N = 230, including a near-record-size specimen) were collected from the north-central GOM via hook and line and were aged using otoliths and first dorsal spines. Total length ranged from 212 to 940 mm, and age ranged from 0.07 to 5.27 years. Otoliths produced higher percent agreement (95.0%) and lower average percent error (3.0%) between readers compared to spines (82.9% and 6.5%, respectively). The von Bertalanffy growth parameters differed slightly between the otolith-based data (mean asymptotic length [L∞] = 762.42 mm, Brody growth rate coefficient [k] = 0.69 year-1, and hypothetical age at which length equals zero [t0] = -0.58 year) and spine-based data (L∞ = 718.83 mm, k = 0.79 year-1, and t0 = -0.56 year). For both otolith- and spine-based sex-specific data, the best-fitting version of the von Bertalanffy growth function permitted L∞ to vary by sex. Chapman-Robson estimates of instantaneous total mortality rate and total annual mortality rate were 1.15 and 68.66%, respectively. Based on empirical, life history-based methods, the instantaneous natural mortality rate was estimated at 0.75-0.97 and the instantaneous fishing mortality rate was estimated at 0.18-0.45, suggesting low levels of exploitation. These growth parameters and mortality estimates will provide information for future stock assessments, thereby ensuring sustainability of the GOM stock of Atlantic Tripletail. [ABSTRACT FROM AUTHOR]

As coastal human populations increase and offshore fishery regulations become more stringent in the northern Gulf of Mexico, nearshore fisheries may be subjected to increased exploitation. Spanish MackerelScomberomorus maculatusand Florida PompanoTrachinotus carolinusare two nearshore, coastal migratory pelagic species vulnerable to undergoing changes in fishing pressure; however, information is incomplete in regards to understanding their current distributions and movement patterns, both of which are important for effective fishery management. We used a 2-year (2011–2012) gill-net and seine survey to assess surf zone distributions of Spanish Mackerel and Florida Pompano in the northern Gulf of Mexico (Horn Island, Mississippi, to Pensacola, Florida). Unbiased catch-per-unit-effort estimates (by the delta method) were greatest in Alabama and during spring months. Lowest catches occurred during the warm summer months. Overall, subadult–adult Spanish Mackerel presence could be predicted (using a delta-lognormal general linear model) by geographic area, beach habitat, and depth. Florida Pompano presence could be predicted by month and beach habitat. For both species, the abundance could not be predicted by any of the examined variables. Juvenile Florida Pompano presence, contrastingly, could be predicted by month and salinity, and abundance by month and water temperature. Both species had spatiotemporal variability in distribution and catch rates, but beach habitat appeared to be a better predictor for subadults and adults of both species, whereas month and salinity were better predictors for juvenile Florida Pompano catches. Greater catches generally corresponded with proposed migration patterns but also suggest that individuals, at least temporarily, leave the surf zone during the day in the warm summer months. Furthermore, although legal-sized individuals of both species can co-occur in the surf zone in the northern Gulf of Mexico, the increase in Spanish Mackerel presence with depth suggests that Spanish Mackerel fisheries could potentially move further offshore to avoid user conflict with Florida Pompano fisheries. Received March 16, 2016; accepted August 1, 2016 Published online October 14, 2016 [ABSTRACT FROM AUTHOR]

In the Baltic Sea, species diversity is relatively low and the introduction of new predator species can have large direct and indirect impacts on native species - both prey and potential competitors. The alien round goby Neogobius melanostomus Pallas, 1811 was introduced to the Baltic Sea in the early 1990s and is now well-established. We examined the feeding habits of male round gobies from the Åland Islands, Finland, where round gobies were first recorded in 2011. Specifically, we tested whether small round gobies (≤165 mm TL) showed size and/or species preferences (using Manly's selectivity index) for two abundant bivalve prey items, the blue mussel Mytilus trossulus Gould, 1850 and the Baltic clam Macoma balthica Linnaeus, 1758. When offered two sizes of clams, small round gobies did not show a prey preference. When offered two sizes of mussels, round gobies selected for small mussels (6 - 9 mm) and against large (10 - 13 mm) mussels. When offered both bivalve species and sizes simultaneously (four prey options), round gobies selected for small blue mussels and against large clams. Combined, these results suggest that small round gobies will selectively feed on the preferred prey if available and if not, their feeding will reflect the availability of various prey items in the environment. In addition, round gobies consumed small (= 38 mm TL) individuals of the native flounder Platichthys flesus Linnaeus, 1758. Round goby and flounder have the potential to overlap in habitat use and previous literature has suggested a diet overlap between the two; however, this is the first evidence of direct predation on flounder by round gobies. [ABSTRACT FROM AUTHOR]

Presumably an individual’s risk of predation is reduced by group membership and this ‘safety in numbers’ concept has been readily applied to investigations of schooling prey; however, foraging in groups may also be beneficial. We tested the hypothesis that, when feeding in groups, foraging of a coastal fish (Florida Pompano, Trachinotus carolinus) on a benthic prey source would be facilitated (i.e. fish feeding in groups will consume more prey items). Although this question has been addressed for other fish species, it has not been previously addressed for Florida Pompano, a fish known to exhibit schooling behavior and that is used for aquaculture, where understanding the feeding ecology is important for healthy and efficient grow-out. In this experiment, juvenile Florida Pompano were offered a fixed number of coquina clams (Donax spp.) for one hour either in a group or as individuals. The following day they were tested in the opposite configuration. Fish in groups achieved greater consumption (average of 26 clams consumed by the entire group) than the individuals comprising the group (average of 14 clams consumed [sum of clams consumed by all individuals of the group]). Fish in groups also had fewer unsuccessful foraging attempts (2.75 compared to 4.75 hr-1) and tended to have a shorter latency until the first feeding activity. Our results suggest fish in groups were more comfortable feeding and more successful in their feeding attempts. Interestingly, the consumption benefit of group foraging was not shared by all – not all fish within a group consumed equal numbers of clams. Taken together, the results support our hypothesis that foraging in a group provides facilitation, but the short-term benefits are not equally shared by all individuals. [ABSTRACT FROM AUTHOR]

Spanish MackerelScomberomorus maculatussupport important commercial and recreational fisheries in the Gulf of Mexico (GOM). Although federally managed because of interstate migrations, harvest, essential fish habitat consideration, and management are largely state issues. Contrary to the accepted paradigm of a well-mixed stock from the GOM to the Atlantic, Spanish Mackerel have been suggested to exhibit reduced movement, and hence mixing, which could lead to areas of localized depletion within the larger stock. We addressed how local abundance patterns responded to changes in harvest pressure, evaluated migration patterns via examining temporal trends in abundance, and determined whether the spatial abundance patterns resembled habitat specialization or generalization. Abundance trends of Spanish Mackerel in Alabama have remained relatively constant from 2001 to 2011 despite a significant increase in commercial harvesting. Seasonal patterns of catch rates coincided with the proposed annual migration. We also observed adult Spanish Mackerel in low salinities (0–10‰) at the mouth of Mobile River during the fall when river discharge is relatively low. This extends the known range of estuarine habitat use by adult Spanish Mackerel. Because Mobile Bay includes various habitat types differing from surf zone and coastal ocean habitats typically inhabited by Spanish Mackerel, capturing Spanish Mackerel near the mouth of Mobile River provides evidence for a habitat generalist strategy. Based on a relatively constant abundance index and year-class strength, the stock seems to be relatively stable even after a drastic increase in commercial harvests in Alabama and heavy exploitation of age-1–3 Spanish Mackerel. The resilience of catch rate trends to changes in local harvest pressure as well as evidence of synchrony among areas in terms of migration suggest the Alabama fishery is influenced by population dynamics of a larger population. Received July 3, 2014; accepted January 12, 2015 [ABSTRACT FROM AUTHOR]

Sedimentation and burial affect a variety of habitats worldwide, especially within coastal marine systems. In the Mediterranean, seagrasses like Cymodocea nodosa are commonly subjected to sedimentation and, although the response of C. nodosa has been documented, few studies have included macrofaunal responses. We used a manipulative field experiment to examine the effects of a single small-scale, pulse burial event on benthic invertebrate macrofauna. Burial did not affect the total abundance, richness, or diversity of higher taxa nor the live abundance or diversity after 5 days. However, live higher taxa richness decreased by day 3. After 5 days, such decrease reversed and partial recovery seemed to occur. Almost 2 months later, three of the buried plots remained with some additional sedimentation, but the other three had lost their sediment. We compared faunal metrics of buried plots between days 5 and 54 and found greater diversity on day 54, providing evidence that macrofaunal recovery apparent 5 days after burial seemed to persist. Although we likely underestimated the effects and can only be conservative with our conclusions, taken together our results suggest small-scale, pulse burial events can have some negative effects on the C. nodosa-associated benthic macrofaunal community, but the community can recover within a few weeks. [ABSTRACT FROM AUTHOR]

As coral reef ecosystems decline in health worldwide, reef-associated fishes are being impacted by changes to their coral reef habitats. While previous studies have shown coral reef structure to affect the demography of reef fishes, changes in reef conditions may also impact the behavior of reef fishes as they cope with altered habitats. In this study, we examined spatial patterns of intraspecific behavioral variation in the bicolor damselfish ( Stegastes partitus) across the fringing reefs of Curaçao (Caribbean Sea), and explored how this behavioral variation associated with physical and social conditions on the reef. Principal components analysis (PCA) condensed physical parameters of the reef into principal component 1 (PC1), comprising depth, coral cover (%), rugosity, and average hole size (cm2), and principal component 2 (PC2), which represented the number of holes. PC1, but not PC2, increased spatially across the reef as the habitat transitioned from coral rubble in the shallows to live coral on the reef slope. This transition in reef structure was paralleled by changes in social conditions including decreases in bicolor damselfish density in habitats with higher PC1 values. The behavior of bicolor damselfish also varied spatially with greater aggression and more frequent shelter use in habitats with lower PC1 values. Path analysis revealed robust associations between this behavioral variation and physical habitat conditions of the reef, indicating that physical - rather than social - habitat variation is the primary determinant of these spatial patterns of intraspecific behavioral variation. Taken as a whole, this coupling between physical reef structure and behavior suggests that reef fish may show altered behaviors on coral reefs degraded by anthropogenic impacts. [ABSTRACT FROM AUTHOR]