Characterization of the mesophotic reef fish community in south Florida,USA

The southeastern coast of Florida, USA supports a substantial recreational fishery, yet little is known of the coral reef ecosystem or fisheries resources past 50 m depth. Fish assemblages associated with low‐relief substrate and three vessel reefs between 50 and 120 m depth off southeast Florida were surveyed by remotely operated vehicles providing the first characterization of the mesophotic fish assemblages in the region. Two distinct assemblages were observed on low‐relief substrate and high‐relief vessel reefs. A total of 560 fishes of 42 species was recorded on 27 dives on low‐relief substrate, and 50 152 fishes of 65 species were recorded on 24 dives on three vessel reefs. Small planktivorous Anthiinae fishes and several economically valuable species were common on vessel reefs but rare on low‐relief substrate. Fish assemblages on vessel reefs more closely resembled those found at similar depths in high‐relief natural areas off east‐central Florida and the Gulf of Mexico than those associated with adjacent low‐relief habitat or nearby coral reef tracts. From a fisheries perspective, these results provide limited support to the hypothesis that in deep‐water regions with limited relief, vessel reefs may provide an opportunity to increase fish diversity and abundance by creating high‐relief habitat without compromising adjacent fish assemblages.     

Carboxymethylcellulase activity in the digestive tracts of fish

The digestive tracts of 138 marine, freshwater and farmed fish representing 42 species were assayed for cellulase activity using viscometry. Activity was exhibited by the majority of fish but the level of activity was variable within and between species and was not located in any particular region of the gut. The majority of omnivorous and piscivorous fish demonstrated nil or slight activity, whereas most'invertivores' † exhibited moderate and high activity levels. This suggests that cellulase activity in fish is the direct result of the ingestion of invertebrates containing cellulase and/or a cellulolytic microflora.     

Empirical Assessment of Fish Introductions in a Subtropical Wetland: An Evaluation of Contrasting Views

We summarized data from eight quantitative fish surveys conducted in southern Florida to evaluate the distribution and relative abundance of introduced fishes across a variety of habitats. These surveys encompassed marsh and canal habitats throughout most of the Everglades region, including the mangrove fringe of Florida Bay. Two studies provided systematically collected density information over a 20-year period, and documented the first local appearance of four introduced fishes based on their repeated absence in prior surveys. Those species displayed a pattern of rapid population growth followed by decline, then persistence at lower densities. Estuarine areas in the southern Everglades, characterized by natural tidal creeks surrounded by mangrove-dominated marshes, and canals held the largest introduced-fish populations. Introduced fishes were also common, at times exceeding 50% of the fish community, in solution holes that serve as dry-season refuges in short-hydroperiod rockland habitats of the eastern Everglades. Wet prairies and alligator ponds distant from canals generally held few individuals of introduced fishes. These patterns suggest that the introduced fishes in southern Florida at present may not be well-adapted to persist in freshwater marshes of the Everglades, possibly because of an interaction of periodic cold-temperature stress and hydrologic fluctuation. Our analyses indicated low densities of these fishes in central or northern Everglades wet-prairie communities, and, in the absence of experimental data, little evidence of biotic effects in this spatially extensive habitat. There is no guarantee that this condition will be maintained, especially under the cumulative effects of future invasions or environmental change.     

Latitudinal variation in spongivorous fishes and the effectiveness of sponge chemical defenses

It has been proposed that predation pressure declines with increasing latitude and a positive correlation exists between predation intensity and the investment into chemical defenses. However, little direct evidence supports the idea that tropical species are better defended chemically than their temperate counterparts. Temperate reefs of the South Atlantic Bight (SAB) off Georgia, USA, provide a unique opportunity to study tropical sponges in a temperate environment. We documented sponge species richness and abundance, sponge predator density, and examined the ability of eight sponge species to chemically deter predation by fishes on two reefs in the SAB. We used rarefaction analysis and ANOVA to compare our results for sponge species richness and density, respectively, with similar published studies conducted on reefs of the sub-tropical Atlantic (i.e., Florida Keys). These analyses were combined with similar statistical comparisons for spongivorous fish species richness and density. Results showed that sponge species richness was lower, but sponge density was higher, on the temperate SAB reefs than on the subtropical reefs. Both spongivorous fish diversity and density were lower on the SAB reefs. The greater abundance of sponges and lower density of predators on SAB reefs suggest a lower frequency of predation on sponges on SAB reefs. Of the eight sponge species assayed from the SAB reefs, five possessed chemical extracts that were significantly less deterrent to fish predators than their tropical/subtropical conspecifics. When the results were combined across all sponge species, the chemical deterrence of fish predators was significantly lower for extracts obtained from the temperate sponge community as compared to the tropical/subtropical assemblage. These results support the more general hypothesis that a lower density and diversity of sponge predators occurs at high as compared to low latitudes in the western Atlantic and may contribute to decreased investment in chemical defenses.     

The response of stream fish to local and reach‐scale variation in the occurrence of a benthic aquatic macrophyte

1. The aquatic macrophyte Podostemum ceratophyllum has been shown to increase stream productivity, abundance and biomass of benthic invertebrates, and local occurrences of some stream fishes. However, experimental evidence that fishes preferentially associate with Podostemum is lacking, and the value of Podostemum as a predictor of stream fish assemblage composition has not been studied. 2. We conducted two short‐term (2 week), small‐scale (36 m²) experimental manipulations of Podostemum cover in the Conasauga River (Georgia and Tennessee, U.S.), and found higher abundances of benthic insectivorous fishes in patches with augmented (>80%) compared to reduced (7%) Podostemum cover. In an observational study, we quantified associations among percent cover of Podostemum, fish species richness, land cover, shoal length and base‐flow turbidity at 20 randomly selected shoals from a 39‐km reach that spanned a gradient of decreasing forest land cover. 3. Richness of all fish species and of lotic fishes peaked in the centre of the study reach, and richness was weakly correlated with predictor variables. Occupancy models for individual species also indicated that longitudinal position was a strong covariate for 13 of 19 species examined, with little support that Podostemum cover influenced occupancy. 4. Local associations may reflect choices by benthic fishes to utilise Podostemum, whereas downstream decline in fish species richness and Podostemum cover may reflect altered capacity of the system to support native species.     

Subtroprical wetland fish assemblages and changing salinity regimes: Implications for everglades restoration

During the 1960s, water management practices resulted in the conversion of the wetlands that fringe northeastern Florida Bay (USA) from freshwater/oligohaline herbaceous marshes to dwarf red mangrove forests. Coincident with this conversion were several ecological changes to Florida Bay’s fauna, including reductions in the abundances of top trophic-level consumers: piscivorous fishes, alligators, crocodiles, and wading birds. Because these taxa rely on a common forage base of small demersal fishes, food stress has been implicated as playing a role in their respective declines. In the present study, we monitored the demersal fishes seasonally at six sites over an 8-year time period. During monitoring, extremely high rainfall conditions occurred over a 3.5-year period leading to salinity regimes that can be viewed as “windows” to the area’s natural past and future restored states. In this paper, we: (1) examine the changes in fish communities over the 8-year study period and relate them to measured changes in salinity; (2) make comparisons among marine, brackish and freshwater demersal fish communities in terms of species composition, density, and biomass; and (3) discuss several implications of our findings in light of the intended and unintended water management changes that are planned or underway as part of Everglades restoration. Results suggest the reduction in freshwater flow to Florida Bay over the last several decades has reduced demersal fish populations, and thus prey availability for apex consumers in the coastal wetlands compared to the pre-drainage inferred standard. Furthermore, greater discharge of freshwater toward Florida Bay may result in the re-establishment of pre-1960s fauna, including a more robust demersal-fish community that should prompt increases in populations of several important predatory species.     

Associations between fish assemblages and environmental factors in nearshore habitats of a subtropical estuary

Salinity and inlet distance were the most consistent indicators of species groupings among the 40 most abundant fish species in the Indian River Lagoon (IRL), Florida. In contrast to findings of other studies conducted on small juveniles and forage fishes in the IRL, this study suggested that distributions of the more mobile organisms are influenced more by physical conditions than by biological interactions. Consequently, environmentally-corrected single-species models will be more effective in assessing changes in stock abundance and habitat preferences of mobile species in the IRL. Because of the fluctuations in physical conditions in the IRL and other estuaries, it may be inappropriate to use biologically based methods that rely solely on species interactions to assess fish stocks in those systems.     

Utilization by fishes of shallow,seagrass-covered banks in Florida Bay: 2. Diel and tidal patterns

Synopsis Diel and tidal patterns in the occurrence of water column fishes were examined on four shallow banks in Florida Bay, using continuous 72h gillnet sets. Patterns in capture rates were presumed to indicate movement of fishes on and off the seagrass-covered banks. Species that were nocturnally active on the banks included Arius felis, Mugil gyrans, Opisthonema oglinum, Harengula jaguana, Elops saurus, Lutjanus griseus, and Bairdiella chrysoura. Diurnal species included Eucinostomus gula, Lagodon rhomboides and Mugil cephalus. Strongylura notata and Mugil curema showed no consistent patterns. At the two sites with significant tidal fluctuation in water level, different activity patterns on the bank relative to tidal stage were evident for several species. At extreme low tides, water column fishes apparently left the banks to avoid stranding. Cycles of fish utilization of the bank habitat are proposed to be related to both availability of prey (diel patterns) and water level (tidal patterns). These cycles in turn influence activity patterns of predators foraging on these fishes.     

Climate extremes drive changes in functional community structure

The response of communities to climate extremes can be quite variable. Much of this variation has been attributed to differences in community‐specific functional trait diversity, as well as community composition. Yet, few if any studies have explicitly tested the response of the functional trait structure of communities following climate extremes (CEs). Recently in South Florida, two independent, but sequential potential CEs took place, a 2010 cold front, followed by a 2011 drought, both of which had profound impacts on a subtropical estuarine fish community. These CEs provided an opportunity to test whether the structure of South Florida fish communities following each extreme was a result of species‐specific differences in functional traits. From historical temperature (1927–2012) and freshwater inflows records into the estuary (1955–2012), we determined that the cold front was a statistically extreme disturbance, while the drought was not, but rather a decadal rare disturbance. The two disturbances predictably affected different parts of functional community structure and thus different component species. The cold front virtually eliminated tropical species, including large‐bodied snook, mojarra species, nonnative cichlids, and striped mullet, while having little affect on temperate fishes. Likewise, the drought severely impacted freshwater fishes including Florida gar, bowfin, and two centrarchids, with little effect on euryhaline species. Our findings illustrate the ability of this approach to predict and detect both the filtering effects of different types of disturbances and the implications of the resulting changes in community structure. Further, we highlight the value of this approach to developing predictive frameworks for better understanding community responses to global change.     

Utilization by fishes of shallow,seagrass-covered banks in Florida Bay: 1. Species composition and spatial heterogeneity

Synopsis Species composition and relative capture rates of water column fishes occurring on the shallow (<1 m), seagrass-covered mudbanks of Florida Bay were assessed using small-mesh gillnets. The fauna was largely temperate, with few tropical representatives, and was similar to the fish community in adjacent basins. There was a high variability in the catch across the Bay, reflecting heterogeneity in both the physical environment and various aspects of the seagrass canopy. The Gulf site, in the northwestern section of the Bay, had the highest species richness and highest capture rates of individual species, relative to other sites. Higher densities of potential prey, greater available foraging area, and organically rich, fine sediments are probably influential in the greater fish utilization of this bank. The greater exchange of western Florida Bay with open Atlantic or Gulf waters is proposed as a secondary factor influencing species richness; the probability of non-resident species occasionally appearing on western banks is greater than in isolated interior sections of the Bay.     

Effects of Introduced Groundwater on Water Chemistry and Fish Assemblages in Central Florida Lakes

We assessed effects of groundwater pumping to elevate lake levels on lake water chemistry and fish population metrics at seven Florida lakes. Following groundwater pumping, lake level fluctuation was reduced and lake water samples increased in mean pH, total alkalinity, total phosphorus, chloride and Secchi depth compared to historical means, indicating a close resemblance to the chemistry of aquifer water in the region. Fish community metrics from the augmented lakes were compared to 36 non-augmented lakes in Florida. The mean values for catch per unit effort, species richness and biomass of harvestable fishes, determined by electrofishing, were lower in augmented lakes compared to non-augmented lakes. Canonical correspondence analysis (CCA) indicated a high probability of a low abundance of individual species in augmented lakes compared to a majority of non-augmented lakes. The augmented lake with the lowest pumping rate exhibited less of a shift in limnological variables from historical values, and had fish population characteristics more closely resembling those of non-augmented lakes. Thus, reduced volumes of groundwater introduction could lower impacts to limnological and fish population characteristics. Augmentation allows for lakes to be utilized for recreational activities, and without augmentation some lakes in central Florida would likely go dry due to groundwater withdrawals for water supply. Therefore, allowing more natural water level fluctuations and possible reductions in total pumpage are recommended to reduce impacts to limnological and fish population characteristics, while still allowing sufficient groundwater pumping to preserve lake habitats.     

Survey of Zoonotic Trematode Metacercariae in Fish from Water systems of Geum-gang (River) in Republic of Korea

The infection status of zoonotic trematode metacercariae (ZTM) was surveyed in freshwater fishes from the water systems of Geum-gang (River) in the Republic of Korea (Korea). A total of 1,161 freshwater fishes from 6 local sites of Geum-gang were examined with the artificial digestion method for 4 years (2012–2015). Clonorchis sinensis metacercariae were detected in 122 (37.2%) out of 328 fishes in the positive fish species from 4 surveyed areas, and their mean intensity was 43 per fish infected. Metagonimus spp. metacercariae were found in 432 (51.7%) out of 835 fishes in the positive fish species from all 6 surveyed areas, and their mean intensity was 30 per fish infected. Centrocestus armatus metacercariae were detected in 285 (75.0%) out of 380 fishes in the positive fish species from 6 surveyed areas, and their mean intensity was 2,100 per fish infected. Echinostoma spp. metacercariae were found in 56 (19.7%) out of 284 fishes in the positive fish species from 5 surveyed areas, and their mean intensity was 10 per fish infected. Clinostomum complanatum metacercariae were detected in 98 (57.3%) out of 171 fishes in the positive fish species from only 2 surveyed areas, and their mean intensity was 11 per fish infected. Conclusively, the endemicity of ZTM is not so high in fishes from water systems of Geum-gang in Korea although it is more or less different by fish species, surveyed areas and ZTM species.     

Community structure of fishes attracted to shallow water fish aggregation devices off South Carolina,U.S.A.

Synopsis Twenty-two fish aggregation devices were deployed in 14 m of water off South Carolina. Species composition and abundance were determined by diver visual census on eight occasions from May through November, 1985. A total of 21 families and 36 species of fishes was observed at 121 stations. Pelagic fishes dominated the fauna with a 99.3% relative abundance, and Decapterus punctatus accounted for 97.6% of the individuals. Caranx crysos, Diplectrum formosum, Decapterus punctatus, Centropristis striata and Monacanthus hispidus were the most frequent species. Total fish abundance, number of species and abundance of four of the six most common species were significantly affected by season. Hurricane activity may have caused a significant drop in pelagic fish abundance at the FADs in July. No significant correlations among species abundances were found after removal of season and FAD type effects. Spatial zonation and seasonal occurrence patterns suggest some competition among pelagic fishes. Several factors that regulate FAD faunal abundance and composition are hypothesized, including: juvenile fish availability, availability of shelter, availability of adequate food resources, interspecific and intraspecific competition, severe sea conditions, and sporadic intrusions of large predatory fishes. It is hypothesized that the abundances of benthic and pelagic FAD fishes are correlated and that there is a direct or indirect energetic link between shallow water pelagic and benthic fish assemblages near FADs.     

Habitat enhancement and native fish conservation: can enhancement of channel complexity promote the coexistence of native and introduced fishes?

Native fishes worldwide have declined as a consequence of habitat loss and degradation and introduction of non-native species. In response to these declines, river restoration projects have been initiated to enhance habitat and remove introduced fishes; however, non-native fish removal is not always logistically feasible or socially acceptable. Consequently, managers often seek to enhance degraded habitat in such a way that native fishes can coexist with introduced species. We quantified dynamics of fish communities to three newly constructed side channels in the Provo River, Utah, USA, to determine if and how they promoted coexistence between native fishes (nine species) and non-native brown trout (Salmo trutta L.). Native and introduced fishes responded differently in each side channel as a function of the unique characteristics and histories of side channels. Beaver activity in two of the three side channels caused habitat differentiation or channel isolation that facilitated the establishment of native species. The third side channel had greater connectivity to and similar habitat as the main channel of the Provo River, resulting in a similar fish community to main channel habitats (i.e. dominated by brown trout with only a few native fish species). These results demonstrate the importance of understanding habitat preferences for each species in a community to guide habitat enhancement projects and the need to create refuge habitats for native fishes.     

Asian aquarium fishes in a Neotropical biodiversity hotspot: impeding establishment, spread and impacts

We provide evidence of reproductive activities of nine Asian freshwater fish species belonging to three families in Atlantic Forest creeks located in the Paraíba do Sul River basin, southeastern Brazil, an area rich in endemic and endangered fish fauna. These non-native fishes were introduced into the natural systems by both accidental and intentional releases from ornamental fish farms in the region. Adults of all species were found reproducing during virtually all year round and showed fractionated spawning. Imature individuals (young-of-the-year and juveniles) were also frequent in the five sites. Most of the total sex ratios were close to 1:1. The frequent releases, warm water temperature, marginal vegetation providing food, protection and spawning sites, and the low richness of native fishes in these creeks can facilitate the establishment process of all species. The creeks can also act as dispersing agents of non-native fishes after flash floods, leading to biotic homogenization or differentiation in the local fish community, competition with native fishes, and parasite dissemination. Given the flourishing aquaculture activity in the area, it is expected that these and other non-native species cause extensive modifications in the regional ichthyofauna.     

The activity of pro- and antioxidant systems in the liver of freshwater fishes during different seasons

The content of lipid peroxidation products--diene conjugates, lipid hydroperoxides, thiobarbituric acid reactive substances (TBARS), vitamins A, E and carotenoids and the activity of antioxidant enzymes--superoxide dismutase, glutathione peroxidase and catalase in the liver of freshwater fishes of different species (silver carp, grass carp and common carp) in different seasons have been studied. It was established the activity of antioxidant defence system in the liver of fish depends significantly on the season and fish species. In particular, the content of lipid peroxidation products in the liver of freshwater fishes at the beginning of winter and spring was significantly higher compared to their content at the beginning of summer and autumn. The superoxide dismutase and glutathione peroxidase activities in the liver of these fish species at the beginning of winter and spring were significantly lower than at the beginning of summer and autumn while the seasonal changes of catalase activity in the liver of fish are expressed insignificantly. The content of vitamins E, A1, A2 and carotenoids in the liver of fishes of different species at the beginning of winter and spring was significantly lower than at the beginning of summer and autumn. The content of lipid peroxidation products and vitamins E, A1 and A2 in the liver of common carp is significantly lower than in the liver of silver carp and grass carp and species differences in antioxidant enzymes activity are insignificant.     

Landscape-scale survey of non-native fishes near ornamental aquaculture facilities in Florida,USA

The Tampa Bay region of Florida exhibits the highest concentration of ornamental aquaculture facilities in the USA. Because of the diversity of aquaculture products (~800 species and varieties) and extensive production history (began in the 1930s and 1940s), this region could be a hotspot for escaped ornamental fish. We evaluated the scope of ornamental fish invasions in this region by examining (1) escape vectors and (2) the distribution of escaped fish. We investigated potential pathways of fish escape including theft/vandalism, fish transport, bird carry-off, and through effluent discharge. Fish were sampled at the effluent discharge and continued into the surrounding environment. The dominant escape vector was through farm effluents; there was no evidence that theft/vandalism, fish transport, or bird carry-off contributed to fish escape. Most captured fish were natives, especially the ubiquitous Eastern Mosquitofish (Gambusia holbrooki). Ornamental species and varieties were also captured, especially cichlids and poeciliids such as the Green Swordtail (Xiphophorus hellerii) and Southern Platyfish (Xiphophorus maculatus). Ornamental fish were often found in the immediate vicinity of fish farms but were rarely captured in the surrounding environment. Catch per unit effort and ornamental fish diversity declined when moving away from the aquaculture facility effluent and was reduced at sites with a detention pond. The observed fish distribution might be due to relatively cold water in sub-tropical Florida, predatory fish in the environment, and additional factors related to the physical or biological habitat. Ultimately, few ornamental fishes have established in this region despite a long period of extensive culture.     

Spatial patterns of fish communities along two estuarine gradients in southern Florida

In tropical and subtropical estuaries, gradients of primary productivity and salinity are generally invoked to explain patterns in community structure and standing crops of fishes. We documented spatial and temporal patterns in fish community structure and standing crops along salinity and nutrient gradients in two subtropical drainages of Everglades National Park, USA. The Shark River drains into the Gulf of Mexico and experiences diurnal tides carrying relatively nutrient enriched waters, while Taylor River is more hydrologically isolated by the oligohaline Florida Bay and experiences no discernable lunar tides. We hypothesized that the more nutrient enriched system would support higher standing crops of fishes in its mangrove zone. We collected 50 species of fish from January 2000 to April 2004 at six sampling sites spanning fresh to brackish salinities in both the Shark and Taylor River drainages. Contrary to expectations, we observed lower standing crops and density of fishes in the more nutrient rich tidal mangrove forest of the Shark River than in the less nutrient rich mangrove habitats bordering the Taylor River. Tidal mangrove habitats in the Shark River were dominated by salt-tolerant fish and displayed lower species richness than mangrove communities in the Taylor River, which included more freshwater taxa and yielded relatively higher richness. These differences were maintained even after controlling for salinity at the time of sampling. Small-scale topographic relief differs between these two systems, possibly created by tidal action in the Shark River. We propose that this difference in topography limits movement of fishes from upstream marshes into the fringing mangrove forest in the Shark River system, but not the Taylor River system. Understanding the influence of habitat structure, including connectivity, on aquatic communities is important to anticipate effects of construction and operational alternatives associated with restoration of the Everglades ecosystem.     

Bitten down to size: Fish predation determines growth form of the Caribbean coral reef sponge Mycale laevis

Interactions between organisms add complexity to ecosystem function, particularly on coral reefs. The Caribbean orange icing sponge Mycale laevis is semi-cryptic, often growing under coral colonies or between coral branches. This association is reportedly a mutualism, with the sponge deterring boring sponges from invading the coral skeleton and the coral providing an expanding surface for sponge growth. But is there an alternative explanation for the proximity of sponge and coral? We examined the importance of fish predation on the growth of the sponge. While the semi-cryptic growth form of M. laevis predominates on reefs off the Florida Keys and the Bahamas Islands, M. laevis grows with a non-cryptic, erect morphology off Bocas del Toro, Panama. Surveys revealed that sponge-eating fishes were rare or absent at Bocas del Toro compared to sites in the Florida Keys. Because past studies were inconsistent about the palatability of M. laevis to fish predators, we conducted feeding experiments with sponges from all three sites. Crude organic extracts of M. laevis from all three sites were palatable to generalist fish predators in aquarium assays, and field feeding assays and caging experiments conducted in the Florida Keys confirmed that spongivorous fishes readily ate exposed fragments of M. laevis. Our results suggest that M. laevis is restricted to its semi-cryptic growth form by spongivorous predators, with corals providing a physical refuge from predation. This alternative explanation supports the broader hypothesis that Caribbean reef sponges can be categorized on the basis of chemical defense into defended, palatable, and preferred species, the last of which are restricted to refugia.     

Movements and Site Fidelity of two Juvenile Fish Species Using Surf Zone Nursery Habitats Along The Southeastern North Carolina Coast

We examined the extent of movements of juvenile Florida pompano, Trachinotus carolinus, and gulf kingfish, Menticirrhus littoralis, along an open ocean beach. Fishes were collected by seine at three sites along Masonboro Island and Carolina Beach, NC between 7 June and 7 July 1995. All specimens 40 mm standard length (SL) were tagged with coded wire tags and released at the capture sites. Between 7 July and 9 August and on 15–16 September Masonboro Island and northern Carolina Beach were surveyed for tagged fish. A controlled tag mortality/retention study was conducted for both species. Overall, 1569 Florida pompano (40–135 mm SL) were tagged. Sixty-one (3.9%) of these were recaptured, and only eight moved away from the original tagging sites. The largest movements by two Florida pompano were 2.1 and 10.5 km. Many fish remained at their original tagging sites for 21–27 days. Of 488 gulf kingfish (36–158 mm SL) tagged, 16 (3.3%) were recaptured. Gulf kingfish also exhibited little movement away from tagging sites during the study, with individuals remaining at original tagging sites up to 21 days. Stock size estimates for Florida pompano ranged from 3354 to 4670 among the tagging sites, with densities ranging from 1.9 to 2.6 fish m^–2. The remarkable site fidelity exhibited by these two species suggests that resources were not limiting or that predation pressure was not high enough to cause large scale movements during the study. This implies that local disturbances could impact behavior or survival of juvenile fishes in the surf zone.