Effects of the cleaner fish Labroides dimidiatus on grazing fishes and coral reef benthos

Territorial and roving grazing fishes farm, and feed on, algae, sediment, or detritus, thus exerting different influences on benthic community structure, and are common clients of cleaner fish. Whether cleaners affect grazing-fish diversity and abundance, and indirectly the benthos, was tested using reefs maintained free of the bluestreak cleaner wrasse Labroides dimidiatus for 8.5 yr (removals) compared with controls. We quantified fish abundance per grazing functional group, foraging rates of roving grazers, cleaning rates of roving grazers by L. dimidiatus, reef benthos composition, and fouling material on settlement tiles. Abundances of ‘intensive’ and ‘extensive’ territorial farmers, non-farmers, parrotfishes and Acanthurus spp. were lower on removal than control reefs, but this was not the case for ‘indeterminate’ farmers and Ctenochaetus striatus. Foraging rates of Acanthurus spp. and C. striatus were unaffected by cleaner presence or cleaning duration. This suggests some robustness of the grazers’ foraging behaviour to loss of cleaners. Acanthurus spp. foraged predominantly on sediment and detritus, whereas C. striatus and parrotfishes grazed over algal turfs. Nevertheless, benthic community structure and amount of organic and inorganic material that accumulated over 3.5 mo on tiles were not affected by cleaner presence. Thus, despite greater abundances of many roving grazers, and consequently higher grazing rates being linked to the presence of cleaners, the benthos was not detectably affected by cleaners. This reveals that the positive effect of cleaners on fish abundance is not associated with a subsequent change in the benthos as predicted. Rather, it suggests a resilience of benthic community structure to cleaner-fish loss, possibly related to multiple antagonistic effects of different grazer functional groups. However, losing cleaners remains a problem for reefs, as the lack of cleaning has adverse consequences for fish physiology and populations.

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Shift in polar benthic community structure in a fast retreating glacial area of Marian Cove, West Antarctica

Scientific Reports ◽

10.1038/s41598-020-80636-z ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Hanna Bae ◽

In-Young Ahn ◽

Jinsoon Park ◽

Sung Joon Song ◽

Junsung Noh ◽

...

Keyword(s):

Community Structure ◽

Benthic Community ◽

Adaptive Strategy ◽

Ecological Impacts ◽

Glacier Retreat ◽

Benthic Diatoms ◽

Subtidal Zone ◽

Benthic Community Structure ◽

Community Shift ◽

Global Issue

AbstractGlacier retreat is a major long-standing global issue; however, the ecological impacts of such retreats on marine organisms remain unanswered. Here, we examined changes to the polar benthic community structure of “diatoms” under current global warming in a recently retreated glacial area of Marian Cove, Antarctica. The environments and spatiotemporal assemblages of benthic diatoms surveyed in 2018–2019 significantly varied between the intertidal (tidal height of 2.5 m) and subtidal zone (10 and 30 m). A distinct floral distribution along the cove (~ 4.5 km) was characterized by the adaptive strategy of species present, with chain-forming species predominating near the glacier. The predominant chain-forming diatoms, such as Fragilaria striatula and Paralia sp., are widely distributed in the innermost cove over years, indicating sensitive responses of benthic species to the fast-evolving polar environment. The site-specific and substrate-dependent distributions of certain indicator species (e.g., F. striatula, Navicula glaciei, Cocconeis cf. pinnata) generally reflected such shifts in the benthic community. Our review revealed that the inner glacier region reflected trophic association, featured with higher diversity, abundance, and biomass of benthic diatoms and macrofauna. Overall, the polar benthic community shift observed along the cove generally represented changing environmental conditions, (in)directly linked to ice-melting due to the recent glacier retreat.

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Do installed stream logjams change benthic community structure?

Limnologica ◽

10.1016/j.limno.2014.09.002 ◽

2014 ◽

Vol 49 ◽

pp. 68-72 ◽

Cited By ~ 2

Author(s):

Todd Wellnitz ◽

Se Yeon Kim ◽

Eric Merten

Keyword(s):

Community Structure ◽

Benthic Community ◽

Benthic Community Structure

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An evaluation of benthic community structure in and around the Sackville Spur closed area (Northwest Atlantic) in relation to the protection of vulnerable marine ecosystems

ICES Journal of Marine Science ◽

10.1093/icesjms/fss004 ◽

2012 ◽

Vol 69 (2) ◽

pp. 213-222 ◽

Cited By ~ 12

Author(s):

Christopher R. S. Barrio Froján ◽

Kevin G. MacIsaac ◽

Andrew K. McMillan ◽

María del Mar Sacau Cuadrado ◽

Philip A. Large ◽

...

Keyword(s):

Community Structure ◽

Benthic Community ◽

Evaluation Process ◽

Marine Ecosystems ◽

Benthic Community Structure ◽

Sponge Spicule ◽

Northwest Atlantic ◽

Depth Limit ◽

Closed Area ◽

Macrofaunal Community

Abstract Barrio Froján, C. R. S., MacIsaac, K. G., McMillan, A. K., del Mar Sacau Cuadrado, M., Large, P. A., Kenny, A. J., Kenchington, E., and de Cárdenas González, E. 2012. An evaluation of benthic community structure in and around the Sackville Spur closed area (Northwest Atlantic) in relation to the protection of vulnerable marine ecosystems. – ICES Journal of Marine Science, 69: 213–222. The benthic macrofaunal community structure is investigated within and around a closed area at Sackville Spur in the Northwest Atlantic to ascertain whether continued exclusion of bottom fishing can be justified. This and other similar closed areas have been introduced by the Northwest Atlantic Fisheries Organisation (NAFO) to protect areas of likely occurrence of taxa that are indicative of vulnerable marine ecosystems (VMEs) from the damaging effects of bottom-contact fishing gear. Results reveal subtle yet significant differences in macrofaunal assemblage composition and community structure between inside and outside the closed area, between above and below the 1200-m depth contour (i.e. the historical depth limit of fishing), and between areas where dense sponge spicule mats are either present or absent. Differences were observed in many assemblage metrics; however, the most revealing was the greater abundance, biomass, diversity, and number of VME indicative taxa inside the closed area than outside. Overall community composition is also significantly different between treatments. Depth, sediment temperature, and the proportion of clay within sediments are important in shaping the faunal assemblage. The importance of the effects of fishing is discussed, although it is not possible to ascertain if fishing is the direct cause behind observed differences in the macrofaunal assemblage. A continued closure of the area is recommended, as well as options for streamlining the evaluation process of other closed areas.

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Hydrologic disturbance and nutrient effects on benthic community structure in midwestern US streams: a covariance structure analysis

Journal of the North American Benthological Society ◽

10.1899/0887-3593(2004)023<0309:hdaneo>2.0.co;2 ◽

2004 ◽

Vol 23 (2) ◽

pp. 309-326 ◽

Cited By ~ 49

Author(s):

C. M. Riseng ◽

M. J. Wiley ◽

R. J. Stevenson

Keyword(s):

Community Structure ◽

Structure Analysis ◽

Benthic Community ◽

Covariance Structure ◽

Covariance Structure Analysis ◽

Benthic Community Structure ◽

Hydrologic Disturbance ◽

Nutrient Effects

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Changes in benthic community structure following construction of a harbour impoundment scheme

Netherlands Journal of Aquatic Ecology ◽

10.1007/bf02084243 ◽

1995 ◽

Vol 29 (3-4) ◽

pp. 449-457 ◽

Cited By ~ 2

Author(s):

J. A. Smith ◽

G. E. Millward ◽

N. H. Babbedge ◽

M. J. Attrill ◽

M. B. Jones

Keyword(s):

Community Structure ◽

Benthic Community ◽

Benthic Community Structure

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Characteristics of Benthos communities in Laoting area of Hebei Province

E3S Web of Conferences ◽

10.1051/e3sconf/202020602024 ◽

2020 ◽

Vol 206 ◽

pp. 02024

Author(s):

Li Guanglou ◽

Cao Hongmei ◽

Ye wei

Keyword(s):

Community Structure ◽

Benthic Community ◽

Dominant Species ◽

Diversity Index ◽

Hebei Province ◽

Benthic Community Structure ◽

Number Of Species ◽

Evenness Index ◽

Sea Area ◽

Richness Index

According to a survey of benthos in the Laoting sea area of Hebei Province on May 24th 2019, a total of 40 benthos species were obtained, of which mollusks have the largest number, followed by annelids and arthropods. The dominant species are Sternaspis sculata and Ringicula doliaris. The number of species obtained in this survey is much lower than the historical average. The diversity index is significantly lower than that in the April 2008 survey, and the evenness index and richness index have declined slightly, indicating that the benthic community structure in this sea area tends to be simplistic, stability tends to deteriorate.

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Slow Community Development Enhances Abiotic Limitation of Benthic Community Structure in a High Arctic Kelp Bed

Frontiers in Marine Science ◽

10.3389/fmars.2021.592295 ◽

2021 ◽

Vol 8 ◽

Author(s):

Christina Bonsell ◽

Kenneth H. Dunton

Keyword(s):

Community Structure ◽

Community Development ◽

Benthic Community ◽

Beaufort Sea ◽

High Arctic ◽

Coralline Algae ◽

Physical Factors ◽

Crustose Coralline Algae ◽

Benthic Community Structure ◽

Kelp Bed

We examined the patterns of propagule recruitment to assess the timescale and trajectory of succession and the possible roles of physical factors in controlling benthic community structure in a shallow High Arctic kelp bed in the Beaufort Sea, Alaska. Spatial differences in established epilithic assemblages were evaluated against static habitat attributes (depth, distance from river inputs) and environmental factors (temperature, salinity, current speed, underwater light) collected continuously over 2–6 years. Our measurements revealed that bottom waters remained below freezing (mean winter temperatures ∼−1.8°C) and saline (33–36) with negligible light levels for 8–9 months. In contrast, the summer open water period was characterized by variable salinities (22–36), higher temperatures (up to 8–9°C) and measurable irradiance (1–8 mol photons m–2 day–1). An inshore, near-river site experienced strong, acute, springtime drops in salinity to nearly 0 in some years. The epilithic community was dominated by foliose red algae (47–79%), prostrate kelps (2–19%), and crustose coralline algae (0–19%). Strong spatial distinctions among sites included a positive correlation between cover by crustose coralline algae and distance to river inputs, but we found no significant relationships between multi-year means of physical factors and functional groups. Low rates of colonization and the very slow growth rates of recruits are the main factors that contribute to prolonged community development, which augments the influence of low-frequency physical events over local community structure. Mortality during early succession largely determines crustose coralline algal and invertebrate prevalence in the established community, while kelp seem to be recruitment-limited. On scales > 1 m, community structure varies with bathymetry and exposure to freshwater intrusion, which regulate frequency of primary and physiological disturbance. Colonization rates (means of 3.3–69.9 ind. 100 cm–1 year–1 site–1) were much lower than studies in other Arctic kelp habitats, and likely reflect the nature of a truly High Arctic environment. Our results suggest that community development in the nearshore Beaufort Sea occurs over decades, and is affected by combinations of recruitment limitation, primary disturbance, and abiotic stressors. While seasonality exerts strong influence on Arctic systems, static habitat characteristics largely determine benthic ecosystem structure by integrating seasonal and interannual variability over timescales longer than most ecological studies.

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