Abundance Of Echinoderms Research Articles

Abundance of Echinoderms on the Coast of Tanjung Balak Island of Palaes Village in North Minahasa, Indonesia

Abundance of Echinoderms on the Coast of Tanjung Balak Island of Palaes Village in North Minahasa, Indonesia

Widespread Coral Bleaching and Mass Mortality of Reef-Building Corals in Southern Mexican Pacific Reefs Due to 2023 El Niño Warming

In May 2023, oceanic and atmospheric anomalies indicated El Niño conditions in the eastern Pacific, followed by coral bleaching in coral communities and reefs of Huatulco. We conducted surveys and sampled coral reef communities from late June to mid–August of 2023 to evaluate the intensity and extent of the changes associated with the warming event. From January of 2023, Huatulco experienced positive sea surface temperature (SST) anomalies; however, beginning in June, the high-temperature anomalies became extreme (>31 °C; ~2 °C above historical records). These high temperatures resulted in extensive coral bleaching in middle–late June and mortality from middle–late July (>50–93%). In addition, the area experienced significant reductions in echinoderm abundance and fish biomass. In 2023, severe bleaching affected coral systems in the Central Mexican Pacific, Gulf of Mexico, and Mexican Caribbean, making this the most devastating marine heatwave event, simultaneously impacting coral reefs across Mexico’s Pacific and Atlantic coasts.

Diversity and Abundance of Echinoderms in Pancuran Beach, Lembeh Island

Diversity and Abundance of Echinoderms in Pancuran Beach, Lembeh Island

Assessing benthic reef assemblages: A comparison between no-take artificial reefs and partially protected natural reefs

The marine protected area (MPA) of the Espiritu Santo Archipelago (ESA; Gulf of California), is exposed to a high level of anthropogenic disturbances, consequently, the local authorities have deployed artificial reefs (shipwrecks) in the ESA area to increase fishing refuges, breeding sites, and tourist attractions. To explore the potential contribution of these artificial reefs as a conservation tool, we compared their benthic community structures (i.e. diversity and live cover categories) to those of the natural reefs. Our results indicate a higher abundance of mollusks on the artificial reefs compared to the natural reefs; a higher echinoderm abundance on the natural reefs; and a very similar species richness of hexacorals between the natural and artificial reefs, with 10 and 9 species recorded respectively. The natural reefs hosted a four-fold higher live cover of hexacorals than the artificial reefs, while the artificial reefs had a higher number of octocoral species, 8 versus 5 on the natural reefs. In addition, the artificial reefs had a 4.6 fold higher octocoral cover than the natural reefs. Overall findings indicate that the benthic community assemblages significantly differ between the natural and artificial reefs, which may be related to their location, structural composition, material, and morphology. These results suggest that shipwrecks have the potential to enhance local reef diversity by increasing the cover and abundance of certain benthic-associated species. Although the shipwrecks do not function as surrogate habitats for the adjacent natural rocky reefs, as no-take areas they provide suitable refuges for several target species (e.g. black coral and mollusks).

Short-Term Response of Deep-Water Benthic Megafauna to Installation of a Pipeline Over a Depth Gradient on the Angolan Slope

Large structures are introduced into deep-water marine environments by several industrial activities, including hydrocarbon exploitation. Anthropogenic structures can alter ecosystem structure and functioning in many marine ecosystems but the responses on continental margins are poorly known. Here, we investigate the short-term response of benthic megafauna to the installation of a 56 km-long 30 cm diameter pipeline on the Angolan Margin (Block 31) from 700 to 1800 m water depth using remotely operated vehicle imagery. Clear depth-related patterns exist in the density, diversity and community structure of megafauna observed in 2013 prior to pipeline installation. These patterns are altered in a subsequent survey in 2014, three-months after pipeline installation. Significant increases in density, particularly in mid-slope regions are observed. Diversity is generally, but not consistently, enhanced, particularly in the shallower areas in 2014. Clear changes are noted in community structure between years. These changes are primarily caused by increases in the abundance of echinoderms, particularly the echinoid Phormosoma sp. indet. There was no evidence of colonisation of the pipeline in three months by visible fauna. The few large anemones observed attached to the pipe may be able to move as adults. The pipeline appeared to trap organic material and anthropogenic litter, and may enhance available food resources locally as well as providing hard substratum. These results indicate complex and ecosystem-dependent responses to structure installation and caution against simplistic approaches to environmental management.

Community structure of echinoderms in seagrass ecosystem of Pandaratan Beach, Tapanuli Tengah Regency, North Sumatera

This study aimed to determine the community structure of echinoderms and how it related to seagrass cover and water chemical and physical parameters in Pandaratan Beach, Tapanuli Tengah Regency. The research was conducted from Maret to April 2018. Data analysis included community structure analysis and Principal Component Analysis (PCA). The result showed that there were seven species of echinoderms from four classes in Pandaratan Beach. The station I had the highest composition of echinoderms, while the lowest noted at station II. The highest abundance of 77 ind/m2 was found at the station I and the lowest of 44 ind/m2 was at station III. The highest diversity index was recorded at the station I, while the highest evenness and dominance index was at station II. Water quality of the waters was still in capacity to support the life of echinoderms. Based on PCA analysis, it was obtained that the abundance of echinoderms was positively correlated with seagrass cover, DO, depth, and phosphate.

Spatial distribution of echinoderms in littoral area of Ambon Island, Eastern Indonesia

Setyastuti A, Purbiantoro W, Hadiyanto. 2018. Spatial distribution of echinoderms in littoral area of Ambon Island, Eastern Indonesia. Biodiversitas 19: 1919-1925. Echinoderms samples were collected in Ambon Island as part of the marine resource inventories designed to study the biodiversity of Maluku Archipelago. The purpose of this works was to investigate the abundance and genus richness of echinoderms within the five sampling sites using single transect orthogonal to the coast consisted of 10-quadrat plot of 5x5m, the distance between plots was 10m at each site. Furthermore, this study also aimed to understand the relation of substrate type and community composition within those five sites. The substrate was classified into four types (sea-grass, macro-algae, sand, rocks and/or dead coral) noted by presence/absence mark at each plot. The differences in total abundance and genus richness among those sites were analyzed using an Analysis of Deviance following a Generalized Linear Models (GLMs) fitted by Poisson and log link. However, in term of genus composition, the data were visualized using a Principal Coordination Analysis (PCoA) plots calculated from Bray-Curtis dissimilarity based on the log (x+1) transformed abundance data. A total of 910 individuals of echinoderms belonging to 19 genera was successfully recorded. Total abundance of echinoderms was different significantly among sites (p<0.05). The most abundant echinoderms were collected from Tanjung Tiram, approximately 68.71 individuals/quadrat, which was almost 1.4 times than those in Liang and even 4 times than those in Suli. The genus composition between sites was significantly different (p<0.05). The composition of substrate types among sites was not significantly different (p>0.05), however the composition of substrates correlated significantly with the composition of echinoderms genus (p<0.05, rho=0.36). In conclusion, more complex the substrate variation in an area will affect the diversity and abundance of Echinoderms community therein.

Current status of the megabenthic community in coastal Fukushima Prefecture, Japan, in the wake of the Great East Japan Earthquake

We conducted fisheries-independent bottom-trawl surveys along the coast of Fukushima, Japan, from 2013 to 2017 to study the megabenthic community structure after the 2011 earthquake, tsunami, and nuclear disaster. Although we observed no substantial changes in biodiversity, total abundance and biomass fluctuated among years, primarily because of temporary increases in the abundance or biomass of small shrimp and squid, or variations in abundance or biomass of mid-sized fishes (i.e. puffers and flatfishes) and large elasmobranchs. Echinoderm abundance and biomass decreased in all areas. Crustacean abundance and biomass were extremely low in the central and southern offshore transects. Our results suggest that there has been no recognizable recovery in the megabenthic community, and megabenthic species off the coast of Fukushima might have been experiencing reproductive or recruitment failure. Further research is needed to reveal the causal factors behind changes in these megabenthic communities.

Riqueza y distribución de equinodermos en los arrecifes rocosos de Punta Amapala y Los Cóbanos, El Salvador

Richness and distribution of Echinoderms in rocky reefs at Punta Amapala and Los Cobanos, El Salvador. In El Salvador, taxonomic and distribution studies of echinoderms are scarce, and most of them are from Los Cóbanos. This research aims to explore the richness and abundance of echinoderms associated with shallow rocky reefs of El Salvador, as well as their relationship between distribution and abiotic variables. Sampling was carried out in Los Cóbanos and Punta Amapala, on the Pacific coast of El Salvador; between February and April 2016, with three-hour workdays during low tide. The sampling techniques used were wandering dive and three transects of 30m in length. The relationship between species and abiotic variables (temperature, salinity, coast distance and roughness) was identified with canonical correspondence analysis. We report seven species in five orders. The temperature and coast distance are strongly related to the distribution of organisms. Holothuria (Halodeima) kerfersteini and Echinometra vanbrunti are related to high temperature and greater distance from the coast; however, Ophiocoma aethiops, O. alexandri and Ophiothrix rudis are conditioned by low temperature and shorter coast distance. Rev. Biol. Trop. 65(Suppl. 1): S92-S100. Epub 2017 November 01.

Diversity of Echinoderms in Balekambang Beach, Malang District, East Java

Echinoderms is a component of biodiversity in the coral reefs. Echinoderms play an important role in ecosystem of coral reefs especially in food web, generally as predators and detritivors. This report aims to understand composition and density relative of fauna echinoderms on the Balekambang beach. The Transect line method were used and data retrieval was conducted at three stations. The result showed that echinoderms found in Balekambang beach consists of 7 species that are included in three classes, they were <em>Phyllachantus imperialis</em>, <em>Tripneustes gratilla</em>, <em>Diadema setosum</em>, <em>Clypeaster</em> <em>reticulatus</em> (Class Echinoidea), <em>Archaster typicus</em> (Class Asteroidea), <em>Ophiotrix fragilis</em> and <em>Macrophiothrix belii</em> (Class Ophiuroidea). The highest abundance of echinoderms on the station where located in the mangrove area which was dominated by <em>Archaster typicus</em>. The diversity of echinoderms on Balekambang beach were moderate category. The observations of chemical and physics parameters of the aquatic environment and the substrate obtained quite optimal for life of Echinoderms

Abundance and size patterns of echinoderms in coastal soft-bottoms at Deception Island (South Shetland Islands, Antarctica)

Deception Island is an active volcano in Antarctic waters under high sedimentation regimes, which may affect the abundance and structure of soft-bottom assemblages. During the summer of 2012–2013, a survey of the shallow water soft-bottom assemblages of Deception Island was carried out to examine patterns of abundance and size structure of the three dominant echinoderms (Ophionotus victoriae, Sterechinus neumayeri and Odontaster validus) at 8 locations encompassing a gradient in proximity from the open ocean, including two depths (5 vs. 15m) per location. Abundance patterns of the three species varied with depth; organisms were typically more abundant at 15 relative to 5m depth. Our results partially supported the hypothesis that echinoderms from locations adjacent to the open ocean present larger abundances. Body sizes varied significantly among locations and depths for the three species and some places presented a density-size pattern. High sedimentation rates, combined with low ice-related disturbance, may be the reason behind the large abundances of echinoderms found in this waters.

Variation in the macrofaunal community over large temporal and spatial scales in the southern Yellow Sea

To detect large, temporal- and spatial-scale variations in the macrofaunal community in the southern Yellow Sea, data collected along the western, middle and eastern regions of the southern Yellow Sea from 1958 to 2014 were organized and analyzed. Statistical methods such as cluster analysis, non-metric multidimensional scaling ordination (nMDS), permutational multivariate analysis of variance (PERMANOVA), redundancy analysis (RDA) and canonical correspondence analysis (CCA) were applied. The abundance of polychaetes increased in the western region but decreased in the eastern region from 1958 to 2014, whereas the abundance of echinoderms showed an opposite trend. For the entire macrofaunal community, Margalef's richness (d), the Shannon-Wiener index (H′) and Pielou's evenness (J′) were significantly lower in the eastern region when compared with the other two regions. No significant temporal differences were found for d and H′, but there were significantly lower values of J′ in 2014. Considerable variation in the macrofaunal community structure over the past several decades and among the geographical regions at the species, genus and family levels were observed. The species, genera and families that contributed to the temporal variation in each region were also identified. The most conspicuous pattern was the increase in the species Ophiura sarsii vadicola in the eastern region. In the western region, five polychaetes (Ninoe palmata, Notomastus latericeus, Paralacydonia paradoxa, Paraprionospio pinnata and Sternaspis scutata) increased consistently from 1958 to 2014. The dominance curves showed that both the species diversity and the dominance patterns were relatively stable in the western and middle regions. Environmental parameters such as depth, temperature and salinity could only partially explain the observed biological variation in the southern Yellow Sea. Anthropogenic activities such as demersal fishing and other unmeasured environmental variables may be more responsible for the long-term changes in the macrofaunal community.

Evidence for a trophic cascade on rocky reefs following sea star mass mortality in British Columbia.

Echinoderm population collapses, driven by disease outbreaks and climatic events, may be important drivers of population dynamics, ecological shifts and biodiversity. The northeast Pacific recently experienced a mass mortality of sea stars. In Howe Sound, British Columbia, the sunflower star Pycnopodia helianthoides—a previously abundant predator of bottom-dwelling invertebrates—began to show signs of a wasting syndrome in early September 2013, and dense aggregations disappeared from many sites in a matter of weeks. Here, we assess changes in subtidal community composition by comparing the abundance of fish, invertebrates and macroalgae at 20 sites in Howe Sound before and after the 2013 sea star mortality to evaluate evidence for a trophic cascade. We observed changes in the abundance of several species after the sea star mortality, most notably a four-fold increase in the number of green sea urchins, Strongylocentrotus droebachiensis, and a significant decline in kelp cover, which are together consistent with a trophic cascade. Qualitative data on the abundance of sunflower stars and green urchins from a citizen science database show that the patterns of echinoderm abundance detected at our study sites reflected wider local trends. The trophic cascade evident at the scale of Howe Sound was observed at half of the study sites. It remains unclear whether the urchin response was triggered directly, via a reduction in urchin mortality, or indirectly, via a shift in urchin distribution into areas previously occupied by the predatory sea stars. Understanding the ecological implications of sudden and extreme population declines may further elucidate the role of echinoderms in temperate seas, and provide insight into the resilience of marine ecosystems to biological disturbances.

Comunidades de equinodermos en la región de Tunantal, Golfo de Cariaco, Venezuela

Echinoderms are relevant in the structure of marine benthic assemblages, both due their diversity and their ecological niche. However, studies related with occurrence, abundance and patterns of distribution of echinoderms in Venezuela are still scarce. In the present study we describe the echinoderms in shallow-waters habitats (corals patches, Thalassia beds, sandy bottom, rocky subtidal shore, and mouth of river) at Tunantal bay, Golfo de Cariaco, Venezuela, an area that face threats related with the increase of urban development. Samples were performed during September - October 2010 and February - April 2011, using quantitative (1 m2 plots) and qualitative diving observations. Measurements include density, number of species, evenness, Shannon diversity and similarities between habitats based on Bray-Curtis and Sorensen Indexes. Differences in the structure of echinoderm assemblages were detected between habitats. The overall number of echinoderm species in the area was estimated in 40 ± 3.02. Coral patches and rocky shores showed more species and abundance, evenness and Shannon diversity than others habitats. Although the former habitats are similar in evenness and Shannon diversity, differences in the structure of the assemblages were detected. In coral habitats Echinometra viridis, Ophiactis savignyi and Ophiothrix angulata were the dominants species of the assemblages, meanwhile in rocky shores E. lucunter and Ophiocoma echinata were dominants in abundance followed by Ophionereis reticulata. Other habitats of the bay (Thalassia beds, sandy bottom and mouth of river) showed very low diversity and abundance of echinoderms, in some cases only occasional occurrence. Substrate heterogeneity is proposed as the main driving factor of the diversity and structure of the echinoderms assemblages in the bay. Moreover coral patches and rocky shores offer a substratum to dominant species (E. viridis, E. lucunter and O. echinata), but habitat differences in terms of substratum, depth and wave stress could explain the differences in the echinoderm assemblage. The overall echinoderm diversity is promoted by the differences of habitats in the bay and the changes of species composition between habitats.

ABUNDANCE AND DIVERSITY OF ECHINODERM IN PARI ISLAND, SERIBU ISLANDS

<p>Pari Island is one of the island in the Seribu Islands region. Abundance of echinoderms in Pari Island waters has been observed since 1969. In this research, data of echinoderms was collected on March 2011 applying quadratic transect method 1 x 1 m2, as well as freely collection methods using snorkel and scuba equipment. Thirteen individuals of echinoderms were collected during the study, one species (Archaster typicus) was found by quadratic transect method and 12 species of echinoderms by freely collection methods. The density of starfish Archaster typicus at the sites was between 2.1 to 4.3 individual/m2.</p><p>Keywords: Echinodermata, distribution, abundance, density, Pari Island, Seribu Islands</p>

ABUNDANCE AND DIVERSITY OF ECHINODERM IN PARI ISLAND, SERIBU ISLANDS

Pari Island is one of the island in the Seribu Islands region. Abundance of echinoderms in Pari Island waters has been observed since 1969. In this research, data of echinoderms was collected on March 2011 applying quadratic transect method 1 x 1 m2, as well as freely collection methods using snorkel and scuba equipment. Thirteen individuals of echinoderms were collected during the study, one species (Archaster typicus) was found by quadratic transect method and 12 species of echinoderms by freely collection methods. The density of starfish Archaster typicus at the sites was between 2.1 to 4.3 individual/m2.Keywords: Echinodermata, distribution, abundance, density, Pari Island, Seribu Islands

Seasonal variability of copepods and cladocerans in Bahía de los Ángeles (Gulf of California) and importance of Acartia clausi as food for whale sharks

Bahía de los Ángeles is located on the Baja Californian coast of the Gulf of California, adjacent to Ballenas Channel. The bay receives a dynamic tidal influence from the channel but is protected by numerous islands. It is a highly productive bay that harbors a high diversity of species, some of them protected such as the whale shark (Rhincodon typus). This study describes the seasonal variability of major zooplankton taxa and copepod and cladoceran species between May 2003 and October 2004. Copepods were dominant during winter and spring (83–99% of the zooplankton abundance), experiencing a dramatic decrease in autumn 2003 (37–66%) and summer 2004 (25–45%). Cladocerans were the second most abundant group, represented by Pseudevadne tergestina and Penilia avirostris. The former species occurred year-round with low abundance in winter, whereas the latter occurred only in summer and autumn. Other holozooplankton taxa contributed with less than 15% of the abundance in most of the samples, while merozooplankton contributed less than 8%, though in October of 2003 and 2004 there was a remarkable abundance of echinoderms and other larvae contrasting with their shortage in other seasons. In winter 2004, temperate-subtropical copepod species dominated, such as Calanus pacificus and Acartia tonsa. The high abundance of copepods during spring obeyed to Acartia clausi (median = 28,034 ind m–3); however, the maximal zooplankton abundance (40,468 ind m–3, 99.5% copepods) came from a sample collected south of Punta Arena, where two whale sharks were observed foraging. The shift in species composition during summer coincides with the predominance of easterly winds described in the literature inducing a reversed circulation and a probable transport of tropical species into the bay during summer and autumn (Centropages furcatus, Subeucalanus subcrassus, Acrocalanus longicornis, Temora discaudata, and Corycaeus amazonicus).

Mesoscale effects of aquaculture installations on benthic and epibenthic communities in four Scottish sea lochs

The broad-scale effects of salmon farming on benthic and epibenthic macrofaunal communities of four Scottish sea lochs (Kishorn, Duich, Hourn and Nevis) with different aquaculture loadings were investigated based on the first benthic surveys to be undertaken in these lochs. Significant variation in the benthic communities was identified between lochs, mainly related to differences in the abundance of echinoderms and polychaetes (the dominant components of the benthic communities). Variance partitioning using partial redundancy analysis suggested that approximately 9.6% of this variation could be related to aquaculture activity in the lochs (as expressed through “production” and previously modelled “impact” levels), as compared to 20.6% attributable to measured environmental factors. Epibenthic communities were dominated by echinoderms and arthropods and there was no significant between-loch variation in epibenthic community composition. No significant differences were apparent in the benthic or epibenthic community assemblages between samples taken within 2000 m of a fish farm and those taken beyond this distance. In general, our results support previous studies suggesting a spatially limited impact of salmon culture installations on the benthos, although impacts on the aquatic food web on a wide spatial scale cannot be ruled out and the link between benthic community variation and aquaculture variables identified through variance partitioning requires further investigation.

Abundance, spatial distribution and habitat relationships of echinoderms in the Cabo Verde Archipelago (eastern Atlantic)

The analysis of spatial variability in distribution and abundance of echinoderms may help in identifying the range of processes that can explain the observed patterns of this important component of benthic communities. The distribution and abundance of the echinoderm assemblage inhabiting the shallow rocky reefs at the Cabo Verde archipelago (where few studies other than descriptive ones have been performed until now) was quantified at three spatial scales (among islands, between locations within islands, and among replicates), at two depth strata, and related to fine-scale variation of habitat structure. Total echinoderm abundance and the abundance of the sea urchins Diadema antillarum and Eucidaris tribuloides, and the holothurian Euapta lappa were heterogeneous at the largest considered scale. Most species and habitat descriptors exhibited spatial variability at finer scales. There were significant relationships between habitat architecture and depth and both assemblage parameters and species abundances. Although the effects of habitat structure were species-specific, the probability of occurrence of Asteroidea, Ophiuroidea and Holothuroidea species was higher in heterogeneous habitats. Meanwhile Echinoidea and Holothuroidea species showed higher correlations to complex habitats. The observed spatial patterns are inferred to reflect behavioural responses to fine-scale microhabitat complexity, as well as broad-scale oceanic variables and recruitment dynamics.

Diversidad y abundancia de equinodermos en la laguna arrecifal del Parque Nacional Cahuita, Caribe de Costa Rica

Diversity and abundance of echinoderms from the reef lagoon at Cahuita National Park, Caribbean from Costa Rica. A total of 15 species of echinoderms (one asteroid, seven ophiuroids, five echinoids and two holothurians) were recorded at the Cahuita National Park reef lagoon, between September and October 2003, using a 1 m2 quadrant. The sites with coral substrate and algae were the most diverse, while those with seagrass and sand were the least. Ophiuroids were the most abundant group with 170 individuals, asteroids were the least abundant. Adding other studies and reports of echinoderms to this study, a total of 23 species have been found at Cahuita National Park, which is the most diverse area on the Caribbean of Costa Rica. We report nine new echinoderm records for Costa Rica’s Caribbean. Rev. Biol. Trop. 53(Suppl. 3): 285-290. Epub 2006 Jan 30.