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Little is known about microhabitat use by Caribbean parrotfishes soon after settlement from the plankton. We monitored the abundance and distribution of recently settled Sparisoma spp. (likely mostly S. viride with some S. aurofrenatum) on 6 × 6 m quadrats (n = 9) on the fringing reef front in Barbados (West Indies) every 15 d for 6 mo. Each quadrat was divided into 1 m2 cells to examine associations between substrate composition and recruit (Stegastes diencaeus and threespot damselfish S. planifrons. Whereas Sparisoma recruits overlapped with longfins and to a lesser extent with threespots, small juveniles overlapped only with threespots. Some of the microhabitat associations with recruits and small juveniles at the cell scale were also found across quadrats. We suggest that the reef front is an important habitat for recently settled Sparisoma in Barbados, where they rely on being cryptic and solitary within turf algae gardens defended by damselfishes to minimize predation. After some growth, they perform a microhabitat shift, perhaps due to increased damselfish aggression. Thus, the early post-settlement dynamics of Caribbean Sparisoma might be strongly influenced by substrate modification by algal-gardening damselfishes.

Studies of coral reef fish recruitment have focused more on factors influencing the return of larvae to reefs and the process of settlement than on factors affecting survival in the plank- ton, despite the well-documented importance of the larval environment for temperate marine spe- cies. We examined the ability of environmental factors to explain temporal patterns of recruitment in 8 taxa of coral reef fishes, distinguishing variables associated with settlement from those associated with the pelagic larval stage. At 10 d intervals over a 17 mo period, we collected newly settled fishes from settlement units in Barbados (West Indies). We collected concurrent data on 3 settlement- associated variables, lunar darkness, wind speed, and tidal amplitude, and 5 larval environment vari- ables, sea-surface temperature, cloud cover, salinity, chlorophyll a concentration, and normalized water-leaving radiance at 555 nm. The last 3 were associated with low-salinity intrusions originating in the Amazon. We used hierarchical partitioning and Mallow's C(p) model selection to identify important variables for each taxon. Temporal patterns of recruitment differed among taxa of which 6 showed significant environmental correlations. Significant settlement variables included lunar darkness and tidal amplitude. Significant larval environment variables were diverse and varied in magnitude and sign across taxa. The effects of larval variables were generally strong relative to settlement variables. The temporal scale of the strongest environmental predictor differed across taxa. Our study supports the views that planktonic factors affecting larval survival substantially influ- ence recruitment in coral reef fishes and that different species are affected differently by a common, temporally variable, planktonic environment.

We monitored the recruitment of 8 fish taxa at 10 d intervals for 1 yr on 5 fringing coral reefs along a 15 km stretch of the west coast of Barbados, using benthic standard monitoring units of recruitment of fishes (SMURFs). SMURFs are designed to sample taxa that settle onto coral rubble, including cryptic species, and to minimize post-settlement predation. We deployed SMURFs in reef habitat to separate meso-scale processes from the small-scale influences of benthic habitat. Recruit- ment of most taxa occurred year-round, but was highly variable, with on average more than 50% of recruits collected on only 14% of the sampling dates, indicating the importance of frequent sampling. Temporal patterns within taxa were concordant across reefs, indicating coast-wide synchronous set- tlement, but differed among taxa. Within reefs, 2 taxa settled more frequently on SMURFs sur- rounded by non-preferred substrate, 1 exhibited the opposite pattern, and the remaining 5 showed no substrate associations. Recruitment to individual SMURFs was seldom correlated among taxa. Among reefs, recruitment of 4 taxa was consistently lower on the central coast and higher at the north and south ends, consistent with a previously identified tidally induced flow regime that reduces onshore larval transport near the center of the west coast; the remaining taxa exhibited other spatial patterns, challenging the generality of the role of hydrodynamics. Overall, this study expands the tax- onomic range of recruitment studies, shows spatially coherent (over kilometers) but temporally vari- able (over tens of days) recruitment and reveals substantial diversity in patterns among concurrently settling taxa.

Marine reef fishes may spend a significant pro- portion of their daily activity budgets visiting cleaning sta- tions. Nevertheless, the roles of ectoparasites and of inter- actions with cleaners in shaping patterns of diel activity in these fishes have been largely ignored, possibly because the importance of cleaning for the hosts remains controversial. In diurnal species, a peak in ectoparasite infestation exists at dawn, suggesting that higher rates of cleaner-seeking dur- ing this time should be beneficial to hosts. In this study, we quantified the diel pattern of visitations to cleaners, as well as other major activities, in female yellowtail damselfish Microspathodon chrysurus on a Barbadian fringing reef. Females of this species leave their territories near dawn at 3 d intervals to spawn on male territories. On non-spawning days, cleaning peaked at dawn, when fish spent >20% of their time with cleaners, and declined thereafter, averaging over 11% of the time budget during the entire day. Supple- mental observations in Puerto Rico and the Virgin Islands also revealed dawn peaks in cleaner-seeking activity. Feed- ing and territory defense together occupied less than 3% of the time budget at dawn, and never seemed frequent enough to interfere with cleaning. On spawning days, 30% of females visited cleaners at male nests or while traveling back to their territories, and 24% visited cleaners on their own territories during revisitation trips before spawning was completed; nevertheless, they spent < 1 ⁄ as much time with cleaners as did non-spawning females. Reduced cleaner- seeking indicates that spawning competes with cleaner visitation in damselfish time budgets, producing a tradeoff between cleaning and reproduction. In the 30 min after spawning, females significantly increased their rate of inter- action with cleaners, compared with the same time on non- spawning days, and regained about 68% of the missed time with cleaners; feeding and aggression did not differ between spawning and non-spawning females. Compensatory post- spawning visiting of cleaners supports the hypothesis that cleaning at dawn is important, probably because of negative consequences of the dawn peak in parasite loads.

Reductions in fishing mortality within no-take coral reef marine reserves can produce gradients in the density and size of fishes across reserve boundaries. Such gradients may be affected by other factors, however, including differences in habitat quality between reserve and non-reserve areas and the movement of fish across reserve boundaries. To examine the effects of protection from fishing mortality and of habitat quality on an assemblage of exploited reef fishes, we measured the spatial patterns of fish density and size on fringing reefs near the boundary of the Barbados Marine Reserve (Barbados, West Indies) and statistically controlled for habitat correlates of fish density and size. Reserve sites supported a higher total density and size of fishes than non-reserve sites. Most species had a non-significantly higher mean density and size at reserve sites. The density and/or size of many species were correlated with the depth, rugosity, and/or substrate composition of sites. After statistically controlling for the effects of habitat correlates, the difference in total density between reserve and non-reserve sites remained significant, and the mean density and size of most species remained non-significantly higher at reserve sites. Neither the mobility of species nor their vulnerability to capture by Antillean fish traps was correlated with their relative difference in density or size between reserve and non-reserve sites. Spearfishing target species had a significantly higher relative difference in size between reserve and non-reserve sites than non-target species. Protection from fishing mortality and higher habitat quality appear to contribute to the increased density and size of fishes on study reefs in the Barbados Marine Reserve, and this difference is not compromised by emigration from the reserve.