Settlement preferences of fouling organisms in relation to settlement plate orientations (original) (raw)
Related papers
Journal of Experimental Marine Biology and Ecology, 1997
Larval settlement of macrofouling invertebrates is affected by the surface energy of the substratum. We followed the development of the fouling community on 10 substrata of differing surface energy to determine if initial effects on settlement manifest themselves over longer time spans as variation in community structure. We monitored two arrays of silanized glass rods for 3 days to assess settlement, then allowed them to remain immersed. After 30 days the coverage of five groups of fouling organisms-barnacles, tubeworms, Bugula neritina (L), encrusting bryozoans and hydrozoans-was quantified for each surface. Silanization treatments had a significant effect on the structure of the fouling community colonizing rods immersed on 26 June 1988. We observed no such effect for a second array immersed on 2 August 1988. The structure of the communities developing on the substrata immersed in June appeared to be unrelated to initial settlement patterns. The composition of the fouling community varied spatially for both experimental arrays. While surface energy may initially be important in determining the settlement of macrofouling organisms, its effects, over the long term, on development of fouling communities appear indirect at best, and are complicated by temporal variation.
Development in an estuarine fouling community: The influence of early colonists on later arrivals
Oecologia, 1980
Experiments were performed to determine if earlier colonists inhibited, enhanced, or were necessary for establishment of later colonists during development of an estuarine fouling community at Lewes, Delaware. We determined the significance of earlier stages on the successional process by functionally removing early colonizing species. Since settlement of sessile invertebrates onto our experimental test plates was seasonal, we were able to accomplish functional removal of early colonists by putting out clean test panels after these species had ceased settling. Comparisons between panels initially submerged at three different times in 1974 and 1975, and between panels put out at one-month intervals throughout the study (to describe seasonal settlement patterns) allowed us to determine interactions between adult populations of earlier colonists and colonizing individuals of later arriving species. The dominant sessile species in our system and their times of settlement were: a barnacle (Balanus improvisus)-April through June, a polychaete (Hydroides dianthus)-July and August, a tunicate (Molgula manhattensis)-June through October, a hydroid (Tubularia crocea)-July through October, and a mussel (Mytilus edulis)-November through April. All successional series eventually came to be dominated by M. edulis, and it persisted as the dominant for over a year. A variety of species interactions were observed. M. edulis inhibited colonization by all other dominants and B. improvisus partially inhibited settlement of M. manhattensis. The presence of adult M. manhanensis had no influence on summer settlement of T. crocea, but the hydroids enhanced settlement of tunicates in the fall. During both years of our study, larger settlements of mussels were noted on panels harboring tunicates and hydroids than on bare surfaces. H. dianthus, on the other hand, became established only on bare substrates, and colonization was almost totally inhibited by other dominants. Development in our fouling community did not conform to any single model of community development presented to date. Instead, components of several models were observed within our relatively simple (in terms of number of species) system. For example, facilitation (enhancement of later colonists by earlier ones) and inhibition (resistance of earlier colonists to invasion by later colonists) were both observed. However, we found no evidence earlier colonists were essential for establishment of the next developmental stage. In fact, inhibitory interactions appeared to be much more prevalent than facilitative interactions. The former
The Effects of Caging on the Colonization of Fouling Organisms in the Upper Bonny Estuary
2002
The effects of caging on the colonization and development of the fouling community in the upper Bonny estuary was studied. The experimental design was such that sets of wooden panels (20x20 cm) were screened with cages constructed with plastic netting while another set was left uncaged. Both sets of panels were submerged below low tide level and sampled fortnightly for seventy-four days. The species settling on the panels (as well as on the mesh of the cage) were identified and examined for percentage cover. Data obtained were subjected to Analyis of Variance or t-tests after arc-sine transformation. Faunal abundance was found to be significantly higher on the mesh of the cage than on the panels (p<0.001). Differences between the caged and uncaged panels were influenced by time as total cover was found to decline with time on the caged panels. Pennaria distichia, Styela sp. and Sabella sp. achieved significantly higher cover on the mesh of the cage than the panels (p<0.001). Some species that settled on the panels (Balanus sp., Membranipora membranacea, Serpula sp, Halichondria sp, Crassostrea gasar) were not found on the mesh of the cage, and both Balanus and M.
An Effective Mesocosm Design for Studying the Settlement and Recruitment of Fouling Organisms
Marine Technology Society Journal, 2017
Mesocosms are a powerful tool in the scientific community. They bridge the gap between laboratory and field studies by creating a contained test apparatus that allows for greater control over test organisms while still exposing them to natural environmental variations. A new mesocosm was designed to monitor the in-situ settlement patterns of barnacles. This paper focuses on testing the efficacy of the mesocosm to manage potential problems such as biofouling, corrosion, and poor water quality. The mesocosm consisted of a PVC cube, where four of the six sides had windows covered with 100-μm plankton mesh. Every 2 days, the cube was rotated so that one of the mesh sides was held out of the water, preventing biofouling from clogging the mesh. Biofouling on the outside of the mesocosm significantly correlated to the days of immersion in the marine environment; the longer a side was immersed, the greater the biofouling coverage (p < 0.05, R2 > 0.50). Therefore, the design successful...
Does primary colonization or community structure determine the succession of fouling communities
Journal of Experimental Marine Biology and Ecology, 2010
Predicting the relevance of initial colonization and subsequent species interactions for succession in marine sessile communities is difficult because the effects of both factors depend on highly variable environmental processes (e.g. currents, topography, upwelling and others). Depending on the successional stage at which a new species arrives, it can either rapidly colonize in large numbers or its colonization success might be suppressed by resident species. In order to assess the roles of (i) initial colonization and (ii) subsequent species interactions on community development, we examined the succession of fouling assemblages that established on artificial substrata during two different seasonal periods, i.e. austral winter/spring and spring/ summer. At 16 weeks of age communities that were initiated in different seasons varied significantly in composition and diversity. During each period (winter/spring and spring/summer), multispecies fouling consortia of different ages (hereafter termed "old" and "young") were reciprocally transplanted between two neighbouring study sites and their succession was documented. After 8 weeks of transplantation communities of different ages maintained their differences in diversity even in the face of environmental change. However, during winter/spring the spreading of the dominant species P. chilensis caused more rapid convergence between all communities at both sites. During the spring/summer period, the high initial abundances of the weak competitor Bugula neritina led to the maintenance of differences between resident and transplanted assemblages within each site. Later colonizers, including the dominant competitor P. chilensis, however, could recruit onto B. neritina and started to spread in the communities. These results suggest that the early and intermediate succession of fouling communities in highly productive marine environments such as the Humboldt Current System is driven by the temporal and spatial variability of propagule supply, while the long-term stability of these communities depends on the identity of colonizers and their competitiveness.
Do artificial substrates favor nonindigenous fouling species over native species?
Journal of Experimental Marine Biology and Ecology, 2007
Exotic species are prominent constituents of fouling communities. If exotic fouling organisms colonize or compete better on a wider range of substrate types than native species, this may partially account for their high abundance in estuaries and bays. We used four artificial and four naturally occurring substrate types to compare initial settlement and percent cover of native and exotic fouling species through six months of community development. Both the identity of common taxa and the total number of species colonizing artificial versus natural substrate types were similar. Despite the similarities in species richness, relative abundance patterns between natural and artificial substrate types varied, particularly as the communities developed. Native species were initially in equal abundance on natural and artificial substrate types. Initially, the two most common exotic species, the colonial tunicates, Botrylloides violaceus Ritter and Forsyth and Botryllus schlosseri (Pallas), were also in similar, but low, abundance on artificial and natural substrates. As the communities developed, there was little change in abundance of exotic or native species on natural substrates. However, on artificial substrates the exotic tunicates increased dramatically and native species declined in abundance. Artificial surfaces may provide a novel context for competitive interactions giving exotic species a more "level playing field" in an environment for which they otherwise might not be as well adapted compared to long-resident native species. Additions of artificial substrates to nearshore environments may disproportionately favor exotic species by increasing local sources of exotic propagules to colonize all types of substrates.
Biofouling, 2003
Protection against biofouling is essential for efficient operation of boats and ships. Restrictions on the use of traditional, toxic antifouling coatings call for new less toxic methods. Future antifouling strategies will likely be based on more specific action against dominant foulers and will require more detailed information about spatial and temporal differences in fouling communities on artificial substrates. In this study, the recruitment and succession of fouling organisms was examined on artificial (PMMA) panels exposed to natural flow speeds on the Skagerrak coast (Sweden). The recruitment of foulers on static panels was then compared to fouling allowed to develop on boat hulls in surveys of new nontoxic coatings. The temporal and spatial variation in recruitment was examined on a monthly interval within the boating season, from May-September. Furthermore, the succession of the fouling community was examined during the same interval. A total of 12 sessile invertebrate species was recorded on the static panels with dominant foulers being the barnacle Balanus improvisus (July-September) and the mussel Mytilus edulis (June-August). The mean abundance during peak settlement on panels after 1 month's deployment was 370+134 individuals dm 72 for B. improvisus and 340+415 individuals dm 72 for M. edulis. The succession of foulers on the panels led to a dominance of M. edulis (maximum of 7470+2830 individuals dm 72 ) over B. improvisus (maximum of 2295+680 individuals dm 72 ). This was in contrast to the fouling development on boat hulls, examined after 4 months exposure in 3 successive years, where B. improvisus was the dominant species (mean abundance 222+104 and maximum 713+527 individuals dm 72 ). Some boats were covered to an extent of almost 100% by B. improvisus with only a few M. edulis (mean abundance 20+16). The biomass of fouling on boat hulls varied from average dry weights of 1.3+1 to 13+5 g dm 72 . These results show that extrapolation from static panels (common in evaluation of antifouling performance) to fouling on boat hulls may be problematic.
Journal of Experimental Marine Biology and Ecology, 1997
During late winter/early spring (1992-1993) a series of 12 tapered channels were placed subtidally in a Long Island, New York (USA) estuary to examine total fouling community development. Rather than relying upon flow-dependent correlations among spatially segregated sites, these channels directly accelerated or decelerated the existing tidal currents 50% (ambient flow speeds ranged from < 2 to > 50 cm/s). In response to experimentally manipulated water flows over five months, the arborescent hydroid Obelia longissima Pallas (1766) accumulated onto Tygon tubing in direct proportion to mean free-stream flow speed, whereas barnacle (Balanus ebumeus Gould) initial settlement and cumulative recruitment along plywood ceilings increased threefold and five-fold, respectively, with a long-term doubling of water speed. These positive flow-dependent results directly contrast those from previous experiments in the same channel apparatus which failed to document any flow enhancement on the growth of suspension-feeding bivalves. 01997 Elsevier Science B.V.
Fouling in natural flows: Cylinders and panels as collectors of particles and barnacle larvae
Journal of Experimental Marine Biology and Ecology, 2007
Fouling of cylinders and panels by particulates and barnacles was studied off of a floating dock system in an estuarine area with semidiurnal tides. On a 5 min scale, over a 14 h interval, Acoustic Doppler Velocimetry (ADV) showed time-dependent variation in speed of mean flow but not in direction. On a 1 s scale, relevant to larval responses, ADV data revealed complex velocity structure. Six settlement experiments, each consisting of 5 blocks of six treatments were conducted. In each treatment there were five cylinders with outer diameters of 0.8, 1.5, 6.5, 11.6 and 31.7 cm and a 30 cm wide by 0.7 cm thick panel. Treatments were varied systematically within blocks and mounted so that 50 cm of each cylinder and panel was exposed. When barnacle fouling occupied 1 to 10% of the space on a 1.5 cm diameter cylinder, experiments were scored for particulate and barnacle fouling. Particulate fouling followed the expectations of deposition of long sticky mucus strands. Some larger diameter cylinders were more efficient collectors of barnacles than smaller diameter cylinders, but the relationship between number of barnacles and cylinder size was variable. The 30 cm wide panels collected barnacles as effectively as 6.5 cm diameter cylinders. In general, cylinders facing perpendicular and oblique downstream to bulk flow, collected the largest numbers of barnacles. Patterns of fouling reflect delivery of particles and larvae as well as their interactions with complex flow and surface geometry. Rocking of the floating docks may explain deviations of settlement from expectations based on mean flows.