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Rhodolith beds in the South-East Pacific

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Erasmo C Macaya at University of Concepción
Erasmo C Macaya
Rafael Riosmena-Rodriguez at Universidad Autónoma de Baja California Sur
Rafael Riosmena-Rodriguez
Roland R. Melzer
Roland R. Melzer
Roland R. Melzer
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Roland Meyer at Zoologische Staatssammlung München
Roland Meyer
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1 23
Marine Biodiversity
ISSN 1867-1616
Mar Biodiv
DOI 10.1007/s12526-014-0254-z
Rhodolith beds in the South-East Pacific
Erasmo C.Macaya, Rafael Riosmena-
Rodríguez, Roland R.Melzer, Roland
Meyer, Günter Försterra & Vreni
Häussermann
1 23
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OCEANARIUM
Rhodolith beds in the South-East Pacific
Erasmo C. Macaya &Rafael Riosmena-Rodríguez &
Roland R. Melzer &Roland Meyer &Günter Försterra &
Vreni Häussermann
Received: 4 April 2014 /Revised: 16 June 2014 / Accepted: 19 June 2014
#Senckenberg Gesellschaft für Naturforschung and Springer-Verlag Berlin Heidelberg 2014
Rhodolith or maërl are the most common terms used for free
living coralline red algae which live and produce sediments
(Nelson 2009). They are common in the North Atlantic,
Mediterranean, tropical West Atlantic, Gulf of California,
Southern Japan, Western Australia and New Zealand (Foster
2001). Rhodolith beds reach the deepest section of the eupho-
tic zone, their maximum is at approximately 286 m (Foster
2001). These beds provide habitat, refuge, settlement sites and
nursery ground for a variety of marine life, but also
information about past and present climate changes and
represent an important economic resource used as fertil-
izer in agriculture (Foster 2001). Climate change, ocean
acidification and fisheries have negative impacts on
rhodolith beds, resulting in calls for conservation
(Hall-Spencer et al. 2010).
In the Eastern Pacific, rhodolith beds are known from the
Gulf of California to Alaska and the Galapagos Islands, Costa
Rica, and Panama. The knowledge on coralline algae along
the Chilean coast is still scarce focusing on crustose and non
free-living forms (e.g. Vidal et al. 2003). Here we give the first
record of rhodolith beds in the South-East Pacific, based on
scientific expeditions to Guarello Island (Madre de Dios Ar-
chipelago, c. 50°S 75°W), Melinka and Amita Island
(Guaitecas, c. 43°S 73°W,), and Robinson Crusoe Island (Juan
Fernandez Archipelago, c. 33°S 78°W).
At three sites, Robinson Crusoe, Guarello and Amita, we
found areas of average downward slope on rocky ground
mixed with sediment spots. At depths from about 10–25 m
many of these spots were covered with rhodolith beds show-
ing a lumpy growth form in Robinson Crusoe (Fig. 1a)and
fruticose habit in Guarello and Amita (Fig. 1b, c). Plants were
approximately 5 cm in diameter and had one or two branches
per cm
2
in lumpy material and four to six branches per cm
2
in
fruticose material. In Melinka (Fig. 1d), rhodoliths with a
lumpy growth form were found at intertidal pools. These
records extend the distribution of rhodoliths and raises inter-
esting questions about their distribution, taxonomy, evolution
and ecology. Thus, rhodolith beds in the South-East Pacific
need to be analyzed in detail in the future and their role in
coastal processes evaluated.
This article is no. 106 from the Huinay Scientific Field Station
E. C. Macaya (*)
Universidad de Concepción, Concepción, Chile
e-mail: emacaya@oceanografia.udec.cl
R. Riosmena-Rodríguez
Universidad Autónoma de Baja California Sur, La Paz, Mexico
R. R. Melzer:R. Meyer
Zoologische Staatssammlung München, Munich, Germany
G. Försterra :V. Häussermann
Pontificia Universidad Católica de Valparaíso, Valparaíso, Chile
Mar Biodiv
DOI 10.1007/s12526-014-0254-z
Author's personal copy
Acknowledgments Funding provided by FONDECYT N° 11110437
to ECM and N° 1131039 to VH.
References
Foster MS (2001) Rhodoliths: between rocks and softplaces. J Phycol 37:
659–667
Hall-Spencer J, Kelly J, Maggs C (2010) Background document for maërl
beds. OSPAR Commission, London, p 36
Nelson WA (2009) Calcified macroalgae—critical to coastal eco-
systems and vulnerable to change: a review. Mar Freshw Res
60:787–801
Vidal R, Meneses I, Smith M (2003) Molecular genetic iden-
tification of crustose representatives of the order
Corallinales (Rhodophyta) in Chile. Mol Phylogenet Evol
28:404–419
Fig. 1 Rhodoliths from South-East Pacific. aRobinson Crusoe, (scale bar 1 cm). bGuarello, cAmita, dMelinka
Mar Biodiv
Author's personal copy
... The first characterization of the inter-and subtidal coastal habitats of Robinson Crusoe Island show the following patterns: a) the dominant substrate varies among the three marine parks, b) a high level of endemism in the different taxonomic groups, c) both 928 species richness and abundance show typical patterns of zonation, increasing from the high intertidal towards the subtidal, though the study sites lack characteristic mussel beds in the mid intertidal and large brown macroalgal belts in the low intertidal, d) algal species richness and abundance were high, both in the intertidal and subtidal zones; however in intertidal habitats the dominant functional groups were corticated (e.g., C. intermedius, C. pusilla, Gelidium, B. intricata), crustose and filamentous algae (e.g., C. firma, C. perpusilla, Polysiphonia sp., Pterosiphonia sp.), while in the subtidal zone corticated foliose algae (e.g., D. skottsbergii, P. fernandeziana) dominated the three study sites and the presence of rhodoliths beds in El Palillo (Macaya et al., 2014), e) herbivorous invertebrates, particularly gastropods, dominated the intertidal, while the subtidal was dominated by detritivores, with H. platei as the most abundant, f) the highest fish abundance was recorded in subtidal habitats at El Palillo, followed by El Arenal and finally Tierras Blancas, while fish were very scarce in the intertidal zones, g) invertivore fishes, consumers of benthic invertebrates, dominated Robinson Crusoe's coastal habitats, which suggests a negative relationship between fish abundance and benthic invertebrate abundance, and h) the composition of sessile communities, mobile invertebrates and fish were clearly distinctive in the three proposed marine parks in Robinson Crusoe. The patterns observed in this first study, integrating inter-and subtidal communities, allow us to propose hypotheses relative to the main factors structuring these coastal communities. ...
... The subtidal habitats of Robinson Crusoe, Easter Island and continental Chile are similar with regards to the dominance of brown and crustose algae (Palma & Ojeda, 2002;Gaymer et al., 2011;Ramírez et al., 2013). Species from the Order Dictyotales are the most abundant on both islands, but the sea floor of Robinson Crusoe differs from that of Easter Island in that it is made up of rocky reefs with high abundances of sessile invertebrates (e.g., Vermetida, Cnidaria) and rhodoliths beds (Macaya et al., 2014). On the other hand, around Easter Island the substrate is also primarily reefs but they are principally coral (Pocillopora sp. and Porites lobata; Gaymer et al., 2011;Wieters et al., 2014). ...
Initial assessment of coastal benthic communities in the Marine Parks at Robinson Crusoe Island
Article
Full-text available
  • Oct 2014
The National Biodiversity Strategy developed in Chile aims to protect 10% of the surface area of the most relevant marine ecosystems. The waters around the Juan Fernández Archipelago were not protected until 2014, when a Multiple Use Marine Protected Area was created in the 12 nautical miles around the archipelago, which includes five marine parks in sites of high conservation value. Three of these parks are located around Robinson Crusoe Island. This study aims to define a baseline for monitoring the impact of the marine protected area and provides ecological information to improve the understanding of coastal marine ecosystems around Robinson Crusoe Island. In addition to a characterization of bathymetry and habitats, intertidal and subtidal communities were sampled using transects and quadrats within the marine parks. We quantified species richness and abundances, which were later organized into functional groups for algae and trophic groups for mobile organisms. Although species richness did not vary between sites nor among the habitats sampled, we observed important differences in species abundance and composition as well as in functional and trophic groups both between sites and habitats. Among our results, we highlight: a) the dominance of endemic algae in intertidal and subtidal (mainly corticated and corticated foliose) habitats, b) high abundances of macroinvertebrate herbivores in intertidal habitats and detrivores in subtidal habitats, c) dominance of invertivorous fish in the subtidal, which are the primary predators of mobile benthic organisms. This characterization includes both the inter and subtidal coastal communities of the Juan Fernández Archipelago. Evaluación inicial de las comunidades costeras de los Parques Marinos en la Isla Robinson Crusoe
View
... In contrast, Robinson Crusoe is part of a group of three isolated volcanic islands known as the Juan Fernández Archipelago (33°S), 650 km off the coast of mainland Chile . The habitat of the subtidal temperate rocky reef that surrounds the island of 47.9 km 2 in area is dominated by a community of turfing and leathery macroalgae (e.g., Padina fernandeziana, Colpomenia sinuosa and Dictyota kunthii) and a high cover of vermetid worms (Serpulorbis sp.), which comprise more than 90% of benthic cover interspersed with rhodolith beds (Ramírez et al. 2013;Macaya et al. 2015). The fish community derives from both the Indo-Pacific Region and South Eastern Pacific continent and is composed of 41 species with 70% endemism (Friedlander et al. 2016;Cowman et al. 2017). ...
Endemic species dominate reef fish interaction networks on two isolated oceanic islands
Article
Full-text available
  • Aug 2021
  • CORAL REEFS
Ecological interactions are found across ecosystems, facilitating comparison among systems with distinct species composition. The balance of positive and agonistic interactions among species may be sensitive to variation in the diversity and abundance of species in a community. We studied marine interaction networks among reef fishes on two oceanic islands characterized by high rates of endemism and restricted population connectivity: Rapa Nui (Easter Island) and Robinson Crusoe Island (Juan Fernandez Archipelago). Specifically, we examined whether the type and strength of behavioral interactions varied between these two isolated fish assemblages, how the relative proportions of agonistic and positive interactions compare, and which are the most important interacting species in each system. Combining detailed interaction records using standardized remote underwater video and visual censuses, we observed: (a) Rapa Nui contains 50% more fish species but half the fish densities than Robinson Crusoe, (b) despite these differences, the total number of interactions and proportion of all potentially interacting species were similar between the two oceanic islands; (c) the species that occupied the greatest proportion of all potential interactions in each community were endemic to their respective islands; (d) the relative frequency of positive and agonistic interactions varied, with more agonistic interactions in the more speciose reef system (Rapa Nui) and more positive interactions where fish densities were higher (Robinson Crusoe); and lastly (e) the relative abundance of each species predicted the interaction strength and the number of interactions across all reef fish species. It is of particular importance to understand the role of endemic species and processes affecting reef fish ecological networks on oceanic islands given the multiple anthropogenic threats to these isolated and vulnerable ecosystems.
View
... Foster (2001) argued that rhodolith beds may be one of earth's "big four" seaweeddominated communities together with kelp forests, seagrass meadows, and nongeniculate coralline algae-dominated tropical reefs. Internationally recognized as unique ecosystems, new rhodolith beds continue to be discovered (Foster 2001;Konar et al. 2006;Teichert et al. 2012;Macaya et al. 2015). The three-dimensional structure of rhodolith beds creates microhabitats for diverse invertebrates and algae, including rare and unusual species, as well as serving as nursery grounds for some commercial species of fish (?) (e.g., Hernández-Kantún et al. 2010;Kamenos et al. 2004a, b;Neill et al. 2015;Peña and Bárbara 2008b;Steller et al. 2003;Teichert 2014). ...
Macroalgae
Chapter
Full-text available
  • May 2019
Macroalgae in mesophotic coral ecosystems are generally understudied compared to corals and fishes yet may be more abundant than coral-dominated reefs given their lower depth limits (> 200 m) and ability to grow over soft and hard bottom habitats. These assemblages are abundant and diverse globally, with changing species composition with increasing depth. Ubiquitous macroalgal assemblages include the red algal rhodolith beds and nongeniculate and Peyssonneliales assemblages; green algal Halimeda beds, meadows, and bioherms and Caulerpa spp. beds; and brown algal Lobophora spp. or Distromium spp. beds, Sargassum spp., and kelps. The use of molecular techniques is elucidating macroalgal diversity and rates of endemism, and molecular data and phylogenetic analyses often show strong cryptic diversity or pseudodiversity when compared with morphoanatomical analyses. Mesophotic macroalgae are important as habitat and may serve as seedbanks or refugia for ecosystem resilience following environmental stress. Invasive algal blooms may be deleterious, particularly with the removal of native herbivores or increasing nutrients. Geomorphologically, calcified species such as rhodoliths and Halimeda spp. are significant global producers of calcium carbonate. Abiotic factors influencing the abundance and distribution of mesophotic macroalgae include temperature, water clarity, nutrients, and currents. In general, threats include rhodolith mining, oil spills, sedimentation, ocean acidification, invasive species, bottom trawling, and eutrophication. The impacts of global warming at mesophotic depths are unknown. Future studies should focus on collections for molecular analyses to evaluate population-level dynamics and connectivity between shallow and mesophotic depths and in situ manipulations to determine competitive interactions and ecophysiological processes in these low-light environments.
View
... Foster (2001) argued that rhodolith beds may be one of earth's "big four" seaweeddominated communities together with kelp forests, seagrass meadows, and nongeniculate coralline algae-dominated tropical reefs. Internationally recognized as unique ecosystems, new rhodolith beds continue to be discovered (Foster 2001;Konar et al. 2006;Teichert et al. 2012;Macaya et al. 2015). The three-dimensional structure of rhodolith beds creates microhabitats for diverse invertebrates and algae, including rare and unusual species, as well as serving as nursery grounds for some commercial species of fish (?) (e.g., Hernández-Kantún et al. 2010;Kamenos et al. 2004a, b;Neill et al. 2015;Peña and Bárbara 2008b;Steller et al. 2003;Teichert 2014). ...
Rhodophyta
Chapter
  • Sep 2017
Rhodophyta, or red algae, comprises a monophyletic lineage within Archaeplastida that includes glaucophyte algae and green algae plus land plants. Rhodophyta has a long fossil history with evidence of Bangia-like species in ca. 1.2 billion-year-old deposits. Red algal morphology varies from unicellular, filamentous, to multicellular thalloid forms, some of which are sources of economically important products such as agar and carrageenan. These species live primarily in marine environments from the intertidal zone to deep waters. Freshwater (e.g., Batrachospermum) and terrestrial lineages also occur. One of the major innovations in the Rhodophyta is a triphasic life cycle that includes one haploid and two diploid phases with the carposporophyte borne on female gametophytes. Red algae are also well known for their contribution to algal evolution with ecologically important chlorophyll-c containing lineages such as diatoms, dinoflagellates, haptophytes, and phaeophytes all containing a red algal-derived plastid of serial endosymbiotic origin. Analysis of red algal nuclear genomes shows that they have relatively small gene inventories of 6,000–10,000 genes when compared to other free-living eukaryotes. This is likely explained by a phase of massive genome reduction that occurred in the red algal ancestor living in a highly specialized environment. Key traits that have been lost in all red algae include flagella and basal body components, light-sensing phytochromes, and the glycosylphosphatidylinositol (GPI)-anchor biosynthesis and macroautophagy pathways. Research into the biology and evolution of red algae is accelerating and will provide exciting insights into the diversification of this unique group of photosynthetic eukaryotes.
View
... Many typical tropical coastal habitats often associated with high biological diversity such as mangroves, seagrass beds and coral reefs are absent, and the coast is dominated by volcanic rock, rhodolith (maerl) pebble and sand substrates. Coralline algal rhodolith beds, which form the only substantial biogenic three-dimensional habitat in shallow waters, are known to support a diverse infaunal community (Macaya et al., 2015;Neill et al., 2015;Torrano-Silva et al., 2015) as well as being important in carbon cycling (Nelson, 2009;Cavalcanti et al., 2014). ...
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Recent studies have improved our understanding of nearshore marine ecosystems surrounding Ascension Island (central Atlantic Ocean), but little is known about Ascension's benthic environment beyond its shallow coastal waters. Here, we report the first detailed physical and biological examination of the seabed surrounding Ascension Island at 100–1000 m depth. Multibeam swath data were used to map fine scale bathymetry and derive seabed slope and rugosity indices for the entire area. Water temperature and salinity profiles were obtained from five Conductivity, Temperature, Depth (CTD) deployments, revealing a spatially consistent thermocline at 80 m depth. A camera lander (Shelf Underwater Camera System; SUCS) provided nearly 400 images from 21 sites (100 m transects) at depths of 110–1020 m, showing high variability in the structure of benthic habitats and biological communities. These surveys revealed a total of 95 faunal morphotypes (mean richness >14 per site), complemented by 213 voucher specimens constituting 60 morphotypes collected from seven targeted Agassiz trawl (AGT) deployments. While total faunal density (maximum >300 m−2 at 480 m depth) increased with rugosity, characteristic shifts in multivariate assemblage structure were driven by depth and substratum type. Shallow assemblages (~100 m) were dominated by black coral (Antipatharia sp.) on rocky substrata, cup corals (Caryophyllia sp.) and sea urchins (Cidaris sp.) were abundant on fine sediment at intermediate depths (250–500 m), and shrimps (Nematocarcinus spp.) were common at greater depths (>500 m). Other ubiquitous taxa included serpulid and sabellid polychaetes and brittle stars (Ophiocantha sp.). Cold-water corals (Lophelia cf. pertusa), indicative of Vulnerable Marine Ecosystems (VMEs) and representing substantial benthic carbon accumulation, occurred in particularly dense aggregations at <350 m but were encountered as deep as 1020 m. In addition to enhancing marine biodiversity records at this locality, this study provides critical baseline data to support the future management of Ascension's marine environment.
View
... Foster (2001) argued that rhodolith beds may be one of earth's "big four" seaweeddominated communities together with kelp forests, seagrass meadows, and nongeniculate coralline algae-dominated tropical reefs. Internationally recognized as unique ecosystems, new rhodolith beds continue to be discovered (Foster 2001;Konar et al. 2006;Teichert et al. 2012;Macaya et al. 2015). The three-dimensional structure of rhodolith beds creates microhabitats for diverse invertebrates and algae, including rare and unusual species, as well as serving as nursery grounds for some commercial species of fish (?) (e.g., Hernández-Kantún et al. 2010;Kamenos et al. 2004a, b;Neill et al. 2015;Peña and Bárbara 2008b;Steller et al. 2003;Teichert 2014). ...
Rhodophyta
Chapter
  • Jul 2016
Rhodophyta, or red algae, comprises a monophyletic lineage within Archaeplastida that includes glaucophyte algae and green algae plus land plants. Rhodophyta has a long fossil history with evidence of Bangia-like species in ca. 1.2 billion-year-old deposits. Red algal morphology varies from unicellular, filamentous, to multicellular thalloid forms, some of which are sources of economically important products such as agar and carrageenan. These species live primarily in marine environments from the intertidal zone to deep waters. Freshwater (e.g., Batrachospermum) and terrestrial lineages also occur. One of the major innovations in the Rhodophyta is a triphasic life cycle that includes one haploid and two diploid phases with the carposporophyte borne on female gametophytes. Red algae are also well known for their contribution to algal evolution with ecologically important chlorophyll-c containing lineages such as diatoms, dinoflagellates, haptophytes, and phaeophytes all containing a red algal-derived plastid of serial endosymbiotic origin. Analysis of red algal nuclear genomes shows that they have relatively small gene inventories of 6,000–10,000 genes when compared to other free-living eukaryotes. This is likely explained by a phase of massive genome reduction that occurred in the red algal ancestor living in a highly specialized environment. Key traits that have been lost in all red algae include flagella and basal body components, light-sensing phytochromes, and the glycosylphosphatidylinositol (GPI)-anchor biosynthesis and macroautophagy pathways. Research into the biology and evolution of red algae is accelerating and will provide exciting insights into the diversification of this unique group of photosynthetic eukaryotes.
View
... En general, las plataformas verticales se caracterizaron por la mayor abundancia de especies sésiles como moluscos vermétidos y algas (Tabla 17), sin embargo, individuos juveniles de la langosta Jasus frontalis ocurrieron en grietas de estas plataformas. Los sustratos rocosos albergaron una mayor abundancia de peces e invertebrados móviles (e.g., el erizo C. rodgersii y la estrella P. calcarata) mientras que los intersticios arenosos fueron dominados por el pepino de mar H. platei y algas crustosas libres denominadas "rodolitos" (verMacaya et al. 2014; Tabla 17). El área de El Palillo se caracteriza además por la alta abundancia de algas corticales foliosas, entre las que destacan D.De los tres sitios de AAVC estudiados, El Palillo exhibe la mayor riqueza de especies endémicas del Archipiélago Juan Fernández (y del conjunto biogeográfico Juan Fernández/Desventuradas) que es un área sin protección (28 especies; dos de ellas sólo estuvieron presentes en El Palillo; Tabla 18).En El Palillo no se observan colonias de lobos marinosTabla 17. ...
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Hard Bottom Macrobenthos of Chilean Patagonia: Emphasis on Conservation of Sublitoral Invertebrate and Algal Forests
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The region of the fjords, channels, and islands of Chilean Patagonia (41° 42'S 73° 02'W; 56° 29'S 68° 44'W) has one of the most rugged coasts and is one of the least studied marine systems worldwide. Over the last two decades, we have collected samples (diving down to 35 m) at more than 500 stations, taken underwater photographs, recorded videos from remotely operated vehicles and carried out a comprehensive literature review on benthic (hard bottom) macroinvertebrates and macroalgae. Based on this research, we propose a subdivision of Chilean Patagonia into three biogeographical provinces and 13 ecoregions. The inventory developed indicates the occurrence of rich and extensive sublittoral associations formed by 13 bioengineering species, conforming 11 types of submarine invertebrates, and two types of macroalgal forests. According to the national inventory of wildlife species by conservation status, six of the invertebrate species thriving in Patagonia belong to one of the categories of threatened species. The main local threats to these habitat-forming species are aquaculture, infrastructure and industrialization projects, fishing, and invertebrate harvesting, as well as threats from climate change and volcanic activities. Finally, we identify knowledge gaps and provide recommendations for the protection and conservation of the biodiversity and ecosystem services provided by these species’ associations.
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Eastern Pacific
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Full-text available
  • Oct 2017
In the Eastern Pacific (EP) the only region where rhodolith beds have been well studied in terms of taxonomy, ecology, distribution and conservation status is the Gulf of California. Outside this region the knowledge of rhodolith-forming species is attributed to the initial separate floristic surveys of Dawson and Lemoine, performed more than 50 years ago. After a detailed review of the published literature and information produced during our expeditions throughout the EP, a total of 36 rhodolith-forming species have been recorded from the Aleutian Islands in Alaska to Guarello Island in Chile. Despite the research efforts developed at present, more species remain to be discovered in the EP, particularly in the Tropical Pacific of Mexico and the Pacific coast of Baja California where we found undescribed species of Sporolithon and Lithothamnion. Therefore, we contend that further studies are needed in order to better catalogue the wide rhodolith-forming species diversity that is extremely relevant for the marine realm of the EP.
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Calcified macroalgae are distributed in marine habitats from polar to tropical latitudes and from intertidal shores to the deepest reaches of the euphotic zone. These algae play critical ecological roles including being key to a range of invertebrate recruitment processes, functioning as autogenic ecosystem engineers through provision of three-dimensional habitat structure, as well as contributing critical structural strength in coral reef ecosystems. Calcified macroalgae contribute significantly to the deposition of carbonates in coastal environments. These organisms are vulnerable to human-induced changes resulting from land and coastal development, such as altered patterns of sedimentation, nutrient enrichment through sewage and agricultural run-off, and are affected by coastal dredging and aquaculture. The consequences of increasing sea surface temperatures and fundamental changes in the carbon chemistry of seawater due to CO2 emissions from anthropogenic activities will have serious impacts on calcifying macroalgae. It is not yet understood how interactions between a range of variables acting at local and global scales will influence the viability of calcifying macroalgae and associated ecosystems. Research is urgently needed on all aspects of the taxonomy, biology and functional ecology of calcifying macroalgae. Without an understanding of the species present, measurement of change and understanding species-specific responses will not be possible.
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Background document on maerl beds
Book
Full-text available
  • Jan 2010
This Background Document on maërl beds has been developed by OSPAR following the inclusion of this habitat on the OSPAR List of threatened and/or declining species and habitats (OSPAR agreement 2008-6). The document provides a compilation of the reviews and assessments that have been prepared concerning this habitat since the agreement to include it in the OSPAR List in 2004. The original evaluation used to justify the inclusion of maërl beds in the OSPAR List is followed by an assessment of the most recent information on its status (distribution, extent, condition) and key threats prepared during 2009-2010. Chapter 7 provides recommendations for the actions and measures that could be taken to improve the conservation status of the habitat. In agreeing to the publication of this document, Contracting Parties have indicated the need to further review these proposals. Publication of this background document does not, therefore, imply any formal endorsement of these proposals by the OSPAR Commission. On the basis of the further review of these proposals, OSPAR will continue its work to ensure the protection of maërl beds, where necessary in cooperation with other competent organisations. This background document may be updated to reflect further developments or further information on the status of the habitat which becomes available.
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Rhodoliths: Between Rocks and Soft Places
Article
  • Oct 2001
  • J PHYCOL
Rhodoliths (maërl) are widely distributed in the worlds' oceans and have an excellent fossil record. Individuals are slow growing, may be long lived (>100 years), and are resilient to a variety of environmental disturbances. Their external morphology and internal growth bands are potential archives of environmental variation at scales of within years to tens of years. At high densities, these free-living non-geniculate coralline algae form rhodolith beds, communities of high diversity that can be severely impacted by resource extraction.
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Molecular genetic identification of crustose representatives of the order Corallinales (Rhodophyta) in Chile
Article
  • Oct 2003
Knowledge on species of the order Corallinales along the coast of Chile is still scarce despite a number of studies and records of other divisions of seaweeds made since the early 20th century. This lack of information is more dramatic among crustose representatives of the order, thus depriving biogeographic studies of a thorough analysis and resulting in inadequately representative accounts of biodiversity. The currently changing taxonomy of the group makes it difficult to identify and differentiate among taxa based on morphological and developmental characters. Therefore, the use of molecular tools has been adopted in this study in order to facilitate identification and comparison of crustose corallines collected at the rocky intertidal between 27 degrees and 48 degrees S along the Pacific temperate coast of South America. A sequence 600bp (in length) from the SSU-rDNA gene was used to identify five taxa to the genus level: Lithophyllum, Spongites, Mesophyllum, Synarthrophyton, and Leptophytum. In all cases, the genus distinction based on morphological characters coincide with designations based on variation in the ribosomal DNA gene sequence. Spongites is the most frequently occurring genus and is found in all localities sampled while the others appear occasionally. Taxa recognition at species level must be examined with caution considering that morphological variability is not well understood in Chile because the SSU-rDNA region sequence does not always stand alone as an unambiguous means of identifying all coralline species. In such cases, more rapidly evolving markers are needed. For example, sequences from the ITS (rDNA) region often provide greater resolution among closely related species and genera. However, the methodology presented here remains a useful tool for species-level identification.
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Chile e-mail: emacaya@oceanografia.udec.cl R. Riosmena-Rodríguez Universidad Autónoma de Baja California Sur Rhodoliths: between rocks and soft places
  • Jan 2001
  • 659-667
  • E C Macaya Paz
  • R R Mexico
  • Melzer
E. C. Macaya (*) Universidad de Concepción, Concepción, Chile e-mail: emacaya@oceanografia.udec.cl R. Riosmena-Rodríguez Universidad Autónoma de Baja California Sur, La Paz, Mexico R. R. Melzer : R. Meyer Zoologische Staatssammlung München, Munich, Germany G. Försterra : V. Häussermann Pontificia Universidad Católica de Valparaíso, Valparaíso, Chile Mar Biodiv DOI 10.1007/s12526-014-0254-z References Foster MS (2001) Rhodoliths: between rocks and soft places. J Phycol 37: 659–667
1 Rhodoliths from South-East Pacific. a Robinson Crusoe, (scale bar 1 cm). b Guarello
  • Fig
Fig. 1 Rhodoliths from South-East Pacific. a Robinson Crusoe, (scale bar 1 cm). b Guarello, c Amita, d Melinka