scholarly journals The relationship between fish abundance and benthic community structure on artificial reefs in the Mid-Atlantic Bight, and the importance of sea whip corals Leptogorgia virgulata

PeerJ ◽  
2019 ◽  
Vol 7 ◽  
pp. e7277 ◽  
Author(s):  
Cara C. Schweitzer ◽  
Bradley G. Stevens

Autogenic engineers (i.e., biogenic structure) add to habitat complexity by altering the environment by their own physical structures. The presence of autogenic engineers is correlated with increases in species abundance and biodiversity. Biogenic structural communities off the coast of Delaware, Maryland, and Virginia (Delmarva) are comprised of multiple species including boring sponge Cliona celata, various hydroids (i.e., Tubularia sp., Obelia sp., Campanular sp.), northern stone coral Astrangia poculata, sea whips Leptogorgia virgulata, and blue mussels Mytilus edulis. Sea whips are soft corals that provide the majority of vertical height to benthic structure off the coast of the Delmarva peninsula. The mid-Atlantic bight is inhabited by several economically valuable fishes; however, data regarding habitat composition, habitat quality, and fish abundance are scarce. We collected quadrat and sea whip images from 12 artificial reef sites (i.e., shipwrecks) ranging from 10 to 24 m depth to determine proportional coverage of biogenic structures and to assess habitat health, respectively. Underwater video surveys were used to estimate fish abundances on the 12 study sites and determine if fish abundance was related to biogenic coverage and habitat health. Our results showed that higher fish abundance was significantly correlated with higher proportional sea whip coral coverage, but showed no significant relationship to other biogenic structure. Assessment of sea whip condition (as a damage index) showed that sea whip corals on artificial reefs off the Delmarva coast exhibited minor signs of degradation that did not differ significantly among study sites.

2017 ◽  
Vol 5 (1) ◽  
pp. 21
Author(s):  
Laurentius T. X. Lalamentik ◽  
Unstain N. W. J. Rembet ◽  
Adnan S. Wantasen

A comprehensive research effort was directed to increase the ecological role of Putus-Putus island coral reefs. This study was an implementation of artificial reef technology as fish colonization locality. The artificial reefs were made of 20x20x100 cm-concrete blocks placed in 6 levels and located at the depth of 8-10 m. Reef fish observations were done three times in two locations. Environmental parameters, such as temperature, salinity and visibility, were also measured. Environmental parameters (temperature, salinity a. Water temperature (29.65oC and 29.64oC) supported the coral growth as well. Salinity distribution  was not significantly different among the study sites.  This study also found 37 reef fish species belonging to 18 families. Number of species varied with observed time and localities. Total number of individuals increased with number of fish species. Mean number of individuals and species of reef fish in locality B were higher than those in locality A. Moreover, the reef fish colonization rate in the study site followed the model y = 4.3801e0.5249x with R2= 0.9297 in the strait and y = 5.0397e0.5493x  with R2= 0.9297 for the Bay. Keywords: Artificial reefs, reef fish. Abstrak Suatu upaya penelitian yang komprehensif diarahkan untuk peningkatan fungsi ekologi terumbu karang Pulau Putus-Putus. Penelitian ini berupa penerapan teknologi terumbu buatan sebagai tempat hunian ikan. Terumbu buatan terbuat dari balok cor beton berukuran 20x20x100 cm bersusun 6 dan ditempatkan pada kedalaman 8-10 m. Pengamatan ikan karang dilakukan 3 kali di 2 lokasi berbeda. Parameter lingkungan, seperti suhu, salinitas, dan kecerahan, juga diukur.    Hasil pengukuran yang diperoleh (29,65 oC dan 29,64 oC) termasuk suhu yang optimal untuk pertumbuhan karang. Dari hasil penelitian, ditemukan 37 spesies yang masuk dalam 18 famili ikan karang. Jumlah spesies yang ditemukan bervariasi pada setiap waktu dan lokasi pengamatan. Pengambilan spesies ikan karang dilakukan pada 2 lokasi dengan masing-masing lokasi dilakukan 3 kali pengambilan sampel. Berdasarkan hasil yang diperoleh (tabel 03) dapat dilihat bahwa jumlah individu bertambah seiring dengan banyaknya jumlah spesies ikan karang yang didapat. Rata-rata jumlah individu dan jumlah spesies ikan karang pada lokasi B lebih banyak. Laju hunian ikan karang di lokasi penelitian mengikuti model y = 4.3801e0.5249x dengan R2= 0,9297 untuk lokasi Selat dan y = 5.0397e0.5493x  dengan R2= 0,9297 untuk lokasi Teluk. Kata kunci : Terumbu buatan, ikan karang


2017 ◽  
Vol 68 (10) ◽  
pp. 1955 ◽  
Author(s):  
James A. Smith ◽  
William K. Cornwell ◽  
Michael B. Lowry ◽  
Iain M. Suthers

Artificial reefs are a widely used tool aimed at fishery enhancement, and measuring the scale at which fish assemblages associate with these artificial habitat patches can aid reef design and spatial arrangement. The present study used rapidly deployed underwater video (drop cameras) to determine the magnitude and spatial scale of associations between a fish assemblage and a coastal artificial reef. Count data from drop cameras were combined with distance and bathymetry information to create a suite of explanatory generalised linear mixed models (GLMMs). The GLMMs showed that artificial reefs can influence surrounding fish abundance, but that the magnitude and scale is species specific. Three of the eight taxonomic groups examined showed a positive association with the artificial reef (with model fit poor for the remaining groups); and depth and bottom cover were also influential variables. The spatial scales of these associations with the artificial reef were small, and it was generally the presence of reef (i.e. a reef bottom type) that explained more variation in fish abundance than did distance to reef. The schooling baitfish yellowtail scad was an exception, and had elevated abundance >50m from the artificial reef. Further distribution modelling of artificial reefs will benefit species-specific design and management of artificial reefs.


2018 ◽  
Author(s):  
James Florisson ◽  
James Tweedley ◽  
Tim Walker ◽  
Jennifer A. Chaplin

There has been a marked increase in the number of artificial reefs being deployed around the world, many of which are designed to increase catches of recreationally-targeted fish species. As artificial reef deployments should be accompanied by clear and measurable goals and thus subsequent environmental impact monitoring and performance evaluation, there is a need to develop cost-effective monitoring programs. This study provides proof of concept for a citizen science approach to monitoring the fish faunas of artificial reefs (Reef Vision). Recreational fishers were recruited to collect video samples using Baited Remote Underwater Video systems and submit the resultant footage for analysis and interpretation by professional scientists. Reef Vision volunteers were able to collect enough data of sufficient quality to monitor the Bunbury and Dunsborough artificial reefs in Geographe Bay, south-western Australia. Data were extracted from the footage and used in robust univariate and multivariate analyses, which determined that a soak time of 45 min was sufficient to capture ≥ 95% of the number of species, abundance, diversity and composition of the fish fauna. The potential for these data to detect differences in the characteristics of the fish fauna between reefs and seasons was also investigated and confirmed. With the continuing deployment of artificial reefs around the world, the use of similar cost-effective citizen science monitoring approaches can help determine the effectiveness of these structures in achieving their aims and goals and provide valuable data for researchers, managers and decision makers. Projects such as Reef Vision can also benefit volunteers and communities by enhancing social values, creating ownership over research projects and fostering stewardship of aquatic resources.


1988 ◽  
Vol 1 (21) ◽  
pp. 23
Author(s):  
Toru Sawaragi ◽  
Ichiro Deguchi ◽  
San-Kil Park

A wave overtopping rate from a sea dike of various toe depths is formulated based on a weir model in an unidirectional flow. To evaluated the wave overtopping rate from a seadike on an artificial reef by the weir model, a numerical procedure for predicting wave transformations including the effect of forced wave breaking on the reef is constructed. After confirming the applicability of the model through experiments with regular and irregular waves, the effect of artificial reef on wave overtopping is discussed. So-called individual wave analysis method is shown to he applicable to the wave overtopping caused by irregular waves.


Author(s):  
Alistair Becker ◽  
Michael B Lowry ◽  
D Stewart Fielder ◽  
Matthew D Taylor

Fisheries enhancement initiatives including marine stocking and artificial reef deployments are becoming increasingly common in many parts of the world. Combining the two by releasing hatchery reared fish onto artificial reefs is used in sea-ranching operations but is an approach rarely adopted for recreational fisheries. Yellowtail kingfish (Seriola lalandi) form a valuable recreational fishery in Australia and in 2018 a pilot stocking program was initiated to enhance this fishery. Fish were released onto estuarine artificial reefs in Botany Bay to evaluate if estuarine artificial reefs are suitable release habitat for juvenile yellowtail kingfish and to monitor their dispersal patterns using acoustic telemetry and a tag-recapture program. Both approaches showed similar patterns, indicating juvenile yellowtail kingfish rapidly dispersed from the release location and can travel at least 60 km during their first weeks in the wild. Twenty percent of the acoustically tagged fish entered nearby estuaries to the north and south and tagged fish were also recaptured in these estuaries, indicating that the estuaries provide habitat for juveniles. There was little interaction between stocked fish and two large coastal artificial reefs positioned near Botany Bay. Stocked yellowtail kingfish will likely disperse rapidly from release locations which is consistent with their pelagic life history. While this may present challenges to fisheries managers, increasing release numbers to maintain stocking densities over a broader area may provide a solution. Future releases of fish on coastal natural and artificial reefs are an important next step in refining stocking practices for this species and will help further identify key juvenile habitats.


<em>Abstract</em>.—Multiple coastal development activities coupled with unsustainable management have caused environmental degradation in the Santa Marta region of Colombia. To mitigate this impact, Ecopetrol entered into alliances with private and government institutions to initiate an integrative artificial reef project in Pozos Colorados Bay. To develop the project’s framework, it was necessary to (1) establish context and objectives, (2) design plans and reef construction, (3) strengthen a target social population, and (4) conduct pre- and postdeployment ecological assessments. The achievement of each objective was met with delays and constraints, mainly due to administrative issues and legal requirements. Nevertheless, interventions and interactions among representatives of the 10 institutions involved in the project, as well as the strong commitment of fishers from three organizations in all stages of the process, were indicators of project’s success. Together, these actions and contributions resulted in the deployment of the first six artificial reefs in a 137-ha area. Moreover, recorded changes in biological assemblages before and after reef deployment (richness: 3–37 species; abundance: 30.3–1,615.7 individuals), along with the presence of commercial, ecological, and endangered important species, support the concept of habitat enhancement procedures used here as a strategy for biodiversity conservation with potential for ecotourism activities. The utilization of this technology should be conducted in compliance with concerted schemes for coastal resource management and precautionary principles, directed towards the conformation of discrete marine reserves as future models of sustainable production in sensitive areas.


Author(s):  
E. Charbonnel ◽  
F. Carnus ◽  
S. Ruitton ◽  
L. Le Direac’h ◽  
J.-G. Harmelin ◽  
...  

2019 ◽  
Vol 65 (3) ◽  
pp. 191-200 ◽  
Author(s):  
Yu Wang ◽  
Jinsheng Sun ◽  
Enjun Fang ◽  
Biao Guo ◽  
Yuanyuan Dai ◽  
...  

Artificial reefs have significantly altered ecological and environmental conditions compared with natural reefs, but how these changes affect sediment bacteria structure and function is unknown. Here, we compared the structure and function of the sediment bacterial community in the artificial reef area, the future artificial reef area, and the control area in Bohai Bay by 16S rRNA genes sequencing. Our results indicated that bacteria communities in the sediment were both taxonomically and functionally different between the reef area and control area. In the artificial reef area, the α-diversity was significantly lower, whereas the β-diversity was significantly higher. Functional genes related to chemo-heterotrophy, nitrate reduction, hydrocarbon degradation, and the human pathogens and human gut were more abundant, whereas genes related to the metabolism of sulfur compounds were less abundant in the artificial reef than in the control area. The differences in bacterial communities were primarily determined by depth in the artificial reef area, and by total organic carbon in the future reef area and control area. This study provides the first overview of molecular ecology to assess the impacts of artificial reefs on the bacteria community.


Oryx ◽  
2012 ◽  
Vol 46 (4) ◽  
pp. 501-507 ◽  
Author(s):  
Nur Fadli ◽  
Stuart J. Campbell ◽  
Kathryn Ferguson ◽  
Jude Keyse ◽  
Edi Rudi ◽  
...  

AbstractWe describe the successful creation of new reef habitat on Pulau Weh, Indonesia. Coral cover on artificial reef modules increased from a mean of 24±SE 2.4% 1 year after the initial attachment of Acropora spp. coral fragments to 64±SE 4.8% after 3 years. The artificial reef modules were also rapidly colonized by coral recruits. Recruit densities were 53±SE 3.2 m−2 on modules that had been submerged for only 1 year, nearly twice as high as recruit densities on natural reef substratum (31±2.8 m−2). Consequently, the original Acropora assemblage had increased to include at least 23 coral taxa, including 10 additional Acropora species. The artificial reefs also supported at least 29 reef fish species, from 11 families. Unfortunately, this initial success in habitat creation was abruptly halted by a rapid rise in sea temperature in May 2010 that killed almost all corals on the artificial reefs and on nearby natural reefs. Notwithstanding the general view that reef rehabilitation is yet to deliver ecological and conservation benefits at meaningful scales, other benefits of this project included raising the awareness of reef conservation in the local community, promotion of tourism on Pulau Weh and job creation. We conclude, therefore, that habitat creation has a legitimate role as part of an integrated marine conservation strategy.


Sign in / Sign up

Export Citation Format

Share Document