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The freshwater rockpools support high endemic biodiversity but are poorly studied habitats in the Western Ghats biodiversity hotspot. These freshwater rock pools are situated on outcrops at various elevations in the Western Ghats and are composed of different bedrocks such as laterite and basalt. We aimed to analyze the water quality, geographical position based differences in the water chemistry and the role of bedrock in determining the water chemistry of the rock pools. Our study showed a wide range of water quality variables such as pH, conductivity, and ionic contents that attributed to the natural variation. We observed a drastic variation in the anions and cations at low elevation pools. Rock type and precipitation are influencing the ionic concentration; for example, Calcium and Bromide could be attributed to the seasonal precipitation and geomorphology. This documentation of physicochemical properties of the Western Ghats rock pools can form a baseline for further detailed studies. HIGHLIGHTS The water quality across rock outcrops of Western Ghats is documented.; 80 different rockpools show high variation in the physicochemical composition.; Water quality of the rock outcrops is suitable for supporting aquatic life.; Rock type and precipitation influence the ionic concentration of water.;

The substitution of natural habitats with artificial structures, such as coastal defence structures, has significantly detrimental effects on the marine biological community. In this context, the application of ecological engineering to marine ecosystems presents an opportunity to mitigate these environmental impacts and enhance ecosystem services. There are proposals aimed at mimicking structures found in the natural environment to increase topographic complexity in artificial substrates, thereby promoting biodiversity and hindering the establishment of invasive species. The present study focuses on assessing change in the biological community of intertidal pools constructed on existing coastal defence structures and their influence on a halo (5 cm) of humidity created around the pools. Using an inexpensive method, the tidepools were created at the beginning of 2014 using a pneumatic hammer (DeWalt brand D25902K), imitating the tidepools of the adjacent natural substrate. The coastal defence structures (riprap) which were selected for the study host climax communities since they were built >8 years ago. After 7.5 years of the creation of this microhabitat, the value of species richness in the tidepool was 64.2% higher than in the control, Shannon diversity 41.54% and functional diversity 6.27%. The study of the effect on a halo (5 cm) of humidity produced around the pool shows that Shannon diversity is higher than in the control treatment, demonstrating that the microhabitat created mitigates the harsh environmental (high temperature and desiccation) conditions of the intertidal zone beyond the interior of the tidepool. The results showed that the species richness in the tidepools was bigger in the high intertidal than the low, therefore it is more beneficial to create this microhabitat in high intertidal zone. The created microhabitats serve as shelter and breeding sites for animal species that were not previously observed in the studied artificial structure, as detected for species such as Pisania striata, Ocenebra edwarasii , Stramonita haemastoma , Meralarhaphe neritoides , Siphonaria pectinata, Paracentrotus lividus and Spirorbis sp., thus contribute to reducing the fragmentation of their populations. In terms of "ecological succession", the current study demonstrated that typical species of a mature benthic biological community had colonised the created microhabitat 7.5 years later. These species included the Anthozoa Anemonia sulcata , Actinia equina and Exaiptasia diaphana or the endangered Mollusc Dendropoma lebeche. [ABSTRACT FROM AUTHOR]

Small and temporary freshwater rock pools, compared to lakes, ponds and rivers, have received a very little scientific attention in India. For the present limnological study, six rock pools in the river Chenab at Dhoomi, Akhnoor, were analysed seven times for water quality and fauna during 17-01-2011 to 26-01-2011 and have been described. Among various water parameters depth (6-11 cm), transparency (6-11 cm) and turbidity (1.4-6.88 NTU) recorded a decrease after high record on first observation. Salinity remained constant (0.1 ppt) on all the seven observations. Dissolved oxygen (DO) observed maximum (12.81 mg/l) record on 19-01-2011 and minimum (9.99 mg/l) on 26-01-2011. Chloride (Cl-) was minimum (2.73 mg/l) on 17-01-2011 and 18-01- 2011 and maximum (6.81 mg/l) on 24-01-2011. Conductivity (75.50 - 178.8 µS cm), total dissolved solids (TDS) (40.13 - 85.5 mg/l), Biological oxygen demand (BOD) (2.5 - 6.63 mg/l), pH (8.26 - 9.12), carbonate (CO3 -2) (2.31 - 22.84 mg/l), bicarbonate (HCO3 -) (29.83 - 71.29 mg/l), calcium (Ca+2) (9.45 - 29.50 mg/l), magnesium (Mg+2) (2.24 - 5.38 mg/l), total hardness (TH) (35.34 - 95.80 mg/l) and sodium (Na+) (0.44 - 1.05 mg/l) showed highest record on last observation. Potassium (K+) (0.60 - 1.70 mg/l) was minimum on 18-01-2011 and maximum on 24-01-2011. Nitrate (NO3-) (0.084-0.373 mg/l), phosphate (PO4-) (0.043 - 0.140 mg/l), silicate (SiO4 -4) (1.28 - 3.95 mg/l) and sulphate (SO4 -2) (4.89 - 7.84 mg/l) observed an irregular pulse. Fauna in these rock pools was represented by zooplankton (passive dispersers) belonging to Protozoa (27 species), Rotifera (3 species), gemmules of Porifera (2 species) and Turbellaria (1 species) only. Zooplanktonic maximum qualitative record was observed on 6th observation and quantitative on 7th observation. In the absence of any earlier study on freshwater rock pools in the Himalayan rivers, present work shall be of great help for future workers. [ABSTRACT FROM AUTHOR]

We describe four species of Ochthebius subgenus Cobalius (Coleoptera, Hydraenidae) from coastal rockpools of the western Palaearctic Region: O. anzar sp. nov. (south Morocco, plus a possible specimen from Lanzarote, Canary Islands), O. cortomaltese sp. nov. (Malta), O. evae sp. nov. (Atlantic coast of Morocco and Mediterranean coast of south Spain), and O. gorgadensis sp. nov. (Ilha de Santiago, Cabo Verde). A molecular phylogeny of all described species of Cobalius recovered three clades: (1) O. serratus Rosenhauer, 1864 as sister to the newly defined O. algicola group, including most of the Macaronesian species of Cobalius (O. algicola Wollaston, 1871 from Madeira, O. freyi d'Orchymont, 1941 from Azores, O. lanthanus Ribera and Foster 2018 from Gran Canaria and Lanzarote, and O. balfourbrownei Jäch, 1989 and O. gorgadensis sp. nov. from Cabo Verde); (2) O. anzar sp. nov. as sister to the species of the newly defined O. biltoni group (O. biltoni Jäch and Delgado, 2017 from Sicily, plus O. evae sp. nov. and O. cortomaltese sp. nov.); and (3) the newly defined O. lejolisii group, including O. lejolisii Mulsant and Rey, 1861 (Atlantic coast from south Morocco to the British Islands) plus O. subinteger Mulsant and Rey, 1861 (western Mediterranean), O. adriaticus Reitter, 1886 and its subspecies, O. celatus Jäch, 1989 and O. asper Sahlberg, 1900 stat. rev., previously considered a synonym of O. subinteger (all from the Central and Eastern Mediterranean). We note the strong intrapopulational morphological variation and the contrasting lack of consistent diagnostic characters between populations, despite the deep genetic divergence between lineages found within some species. We also discuss the widespread evolutionary convergence in beetles living in coastal habitats, sometimes in different genera or even families. [ABSTRACT FROM AUTHOR]

Abstract The diversity and structure of epiphytic macrofaunal assemblages on the introduced invasive brown macroalga Sargassum muticum and native fucoids (Bifurcaria bifurcata, Cystoseira humilis, Cystoseira tamariscifolia and Sargassum vulgare) were compared over a 1-year period in intertidal rockpools on the Atlantic coast of Morocco. In comparison with the epiphytic fauna associated to other macroalgae from European shores, we found that the associated epiphytic macrofauna was moderately diverse (H'<3 bit) and was mainly dominated by gastropods and crustaceans. The most abundant taxa were the isopod Dynamene bidentata and the gastropods Steromphala umbilicalis and Steromphala pennanti. The epiphytic macrofauna community structure differed slightly between the invader and the natives along the year. There was significant temporal variation in the total number of individuals of epiphytic macrofauna per thallus dry weight for the associated epifauna with the highest abundance found on C. tamariscifolia in the spring. The composition of the epiphytic macrofauna on each macroalga species was fairly constant over time. Overall, our results demonstrated that the mobile epiphytic macrofauna on this rocky area showed low macroalgal specificity. They also revealed that the invader S. muticum supports similar epiphytic macrofaunal communities as the native brown macroalgae and provides an additional appropriate habitat for a generalist associated epiphytic macrofauna. [ABSTRACT FROM AUTHOR]

We describe a new species ofMicragasmaJ. Sahlberg, 1900 (Coleoptera, Hydraenidae), which is here treated as a subgenus ofOchthebiusLeach, 1815. The new species,O. (Micragasma)minoicussp. n., was found at the margins of a coastal rockpool in the island of Crete. The species differs from the other two known species ofMicragasmain both external and genital characters, but shares with them the presence of small setiferous tubercles on the surface of the head, pronotum and elytra, and a strong medial gibbosity on the head. In some characters, such as the structure and shape of the aedeagus,O. (M.) minoicussp. n. is similar to other species of the genusOchthebius, in particular of the subgenusCobaliusRey, 1886, typical of coastal rockpools. http://zoobank.org/urn:lsid:zoobank.org:act:BCEAE1EE-7C5E-4017-A753-559738221502 [ABSTRACT FROM PUBLISHER]

Nutrient enrichment of coastal waters can enhance the invasibility and regrowth of non-native species. The invasive alga Caulerpa cylindracea has two distinct phases: a well-studied fast-growing summer phase, and a winter latent phase. To investigate the effects of nutrient enrichment on the regrowth of the seaweed after the winter resting-phase, a manipulative experiment was carried out in intertidal rockpools in the North-western Mediterranean. Nutrients were supplied under different temporal regimes: press (constant release from January to May), winter pulse (January to March) and spring pulse (March to May). Independently from the temporal characteristics of their addition, nutrients accelerated the re-growth of C. cylindracea after the winter die-back, resulting in increased percentage covers at the peak of the growing season. Nutrient addition did not influence the number and length of fronds and the biomass. Native components of the algal community did not respond to nutrient additions. Our results show that nutrient supply can favour the spread of C. cylindracea even when occurring at a time of the year at which the seaweed is not actively growing. [ABSTRACT FROM AUTHOR]

The goal of this study was to provide the first scientific data of the intertidal ichthyofauna community of Peniche. In order to have an accurate assessment, anesthetics were used, since this method is more effective than visual census. Therefore, the ideal concentration of clove oil to be used as anesthetics for local rock pool fish was tested. Through laboratory experiments with some of the most common species in the area, the concentration 30 mg.L-1was considered ideal. A total of 4 rockpools were sampled between May and July 2012, in two different locations (2 in Praia da Gamboa and 2 in Portinho da Areia Norte), in Peniche (West of Portugal). A total of 508 fishes belonging to 17 different species were registered. Fish abundance, occurrence frequencies and sizes were registered and compared for the two beaches and for the respective tide pools. The most abundant species was Gobius n.sp. while the most frequent was Gobius paganellus. These two species represent 59.1% of all captured species. Praia da Gamboa was the location with the highest abundance of individuals while Portinho da Areia Norte was the location where larger individuals were collected. It was observed that the size of rockpools affects abundance and density of individuals. Substrate, number and type of shelters also affect density, abundance and the mean size of individuals. Considering the studies focusing on intertidal ichthyofauna worldwide are relatively scarce, and being this ecosystem absolutely crucial both for biological but also socio-economic reasons worldwide, a better understanding of this unique ecosystem is mandatory, so it is possible to understand it, in order to preserve it.

Spatial and temporal patterns of abundance and distribution of sea urchins ( Paracentrotus lividus ) from intertidal rockpools of the north Portuguese coast were examined in relation to physical (surface, altitude, depth, topographic complexity and exposure) and biological (substrate cover by dominant organisms) habitat traits. The methodology was based on a multi-factorial design where the total number and the abundance of urchins in each of six size classes were sampled over a range of spatial scales, from 10s of cm to kms, and a temporal scale of five months. The results highlighted three main features of the studied system: (1) the largest proportion of variability of sea urchins occurred at the smallest scale examined; (2) urchins from different size classes showed different patterns of abundance in relation to habitat traits; (3) variables normally invoked as potential drivers of distribution of urchins at a range of scales, such as hydrodynamics and shore height, were relatively less important than other abiotic (i.e. pool area, pool mean depth calculated over five replicate measures and sand cover) and biological (i.e. space occupancy by the reef-forming polychaete Sabellaria alveolata and mussels vs. availability of bare rock) variables to provide a considerable contribution to the variability of sea urchins. Intertidal populations of sea urchins are abundant on many rocky shores, where they are socially and economically important as food resource and ecologically key as habitat modelers. This study provides new clues on relatively unstudied populations, with relevant implications for possible management decisions, including the implementation of protection schemes able to preserve the main recruitment, settlement and development areas of P. lividus . [ABSTRACT FROM AUTHOR]

A total of 15 species of ostracods of 7 genera and 3 families of the suborder Podocopa Sars have been recorded in rockpools of the Kandalaksha Bay in the White Sea. Among them, Potamocypris pallida Alm is a new species for the fauna of Russia. Data on species composition and the dominant complex and ecological features of ostracods which inhabit waters of rockpools are presented. [ABSTRACT FROM AUTHOR]

Abstract: Increasing levels of eutrophication in coastal waters and recognition of natural variation in supply of nutrients, through for example variations in upwelling intensity, have led to an increasing demand to understand the role of bottom up forcing in coastal communities. Rocky intertidal habitats are highly disturbed and are composed of a patchy mosaic of assemblages in different successional stages. The role of consumer control of algae in such habitats is well recognised but the way consumer control interacts with variation in resource supply is still debated. We examined, using a factorial manipulative experiment, the way top down control by molluscan grazers interacts with nutrient supply to determine the community composition and productivity of early successional communities in intertidal rockpools. The experiment was run over a six-month period, through the summer months, when nutrients were potentially limiting. Rockpools were cleared of biota and nutrient supply enhanced using slow release fertiliser, while the level of molluscan grazing was reduced through regular removals. Macroalgal colonisation was rapid. Positive effects of nutrient enrichment on macroalgal cover were generally lower than the negative effects of grazer control, although at the peak of algal cover, nutrient effects were apparent irrespective of grazer treatment. There were distinct differences in the identity of dominant species among nutrient treatments with green Ulva spp. dominating under enhanced nutrient conditions and red Ceramium spp. dominating under ambient conditions. These differences contributed to a mismatch between effect estimates based on cover and those based on direct measures of productivity. The use of percentage cover as a surrogate of biomass in intertidal studies is discussed. The results indicate that in a disturbed environment enhanced nutrient supply can stimulate macroalgal blooms despite strong top down control by intertidal grazers. [Copyright &y& Elsevier]

Low-intertidal fish communities, including Enneapterygius rufopileus (Tripterygiidae), were studied in rockpools in Sydney, Australia to consider the role of physical factors and food availability in their distribution and abundance. The rockpool fish community in Sydney was speciose (23 species), of which 35% of individuals were E. rufopileus. Fish abundance and 13 physical and biological parameters were measured in twenty-two rockpools spread among 4 sites. Abundance of E. rufopileus was best predicted by the number of rock overhangs, algal cover (Zonaria sp. and Hormosira banksii), and the encrusting ascidian cunjevoi (Pyura sp.). Experimental increase or decrease in available shelter (mainly boulders and macroalgae) in rockpools did not significantly affect the abundance of fishes, however some pools consistently supported more fishes in total, despite repeated defaunation, indicating that underlying deterministic processes may have a significant effect on rockpool fish communities. The diet of Enneapterygius rufopileus included unidentified crustacean remains, harpacticoid copepods, and gastropods. Gastropod abundance was greater in the diets of larger fish, which also consumed more food overall. Total weight of food was not dependent on E. rufopileus density in pools or the densities of all fish species in pools. Therefore, the study does not support the hypothesis that resources were limiting for this fish species in rockpools. [ABSTRACT FROM AUTHOR]

We examined the spatial distributions of the microparasites on two species of Daphnia in rockpools in four areas along the coast of the Gulf of Bothnia, central Sweden. We found five taxa of parasites, of which the microsporidian Larssonia sp. occurred in all the four subareas studied, and in 44% of the pools. Other parasites, such as a microsporidian intestinal parasite of the Glugoides type and the nematode Echinura uncinata, were much less common. Larssonia had a large impact on reproduction in both Daphnia species, although D.␣longispina seemed to be somewhat less affected than D.␣pulex. We used a spatial autocorrelation method (correlogram using Moran's coefficient) to analyse the spatial distribution of the two Daphnia species and the most abundant parasite species Larssonia sp. All three species showed positive spatial autocorrelations over small distances, indicating an aggregated distribution. This suggests that colonization-extinction dynamics may be important in both host species as well as in the parasite. Larssonia showed no relation to environmental factors, while the distributions of the two Daphnia species were significantly related to the water volume of the pools. D. pulex was more often found in small pools, while D. longispina more often inhabited larger pools. Our study suggests that microparasites in rockpools have substantial effects on Daphnia demography and through this they may influence population dynamics and local extinctions. [ABSTRACT FROM AUTHOR]