Long-term growth rates of four Mediterranean cold-water coral species maintained in aquaria

Abstract. Here we show the use of the 210Pb-226Ra excess method to determine the growth rate of two corals from the world's largest known cold-water coral reef, Røst Reef, north of the Arctic circle off Norway. Colonies of each of the two species that build the reef, Lophelia pertusa and Madrepora oculata, were collected alive at 350 m depth using a submersible. Pb and Ra isotopes were measured along the major growth axis of both specimens using low level alpha and gamma spectrometry and trace element compositions were studied. 210Pb and 226Ra differ in the way they are incorporated into coral skeletons. Hence, to assess growth rates, we considered the exponential decrease of initially incorporated 210Pb, as well as the increase in 210Pb from the decay of 226Ra and contamination with 210Pb associated with Mn-Fe coatings that we were unable to remove completely from the oldest parts of the skeletons. 226Ra activity was similar in both coral species, so, assuming constant uptake of 210Pb through time, we used the 210Pb-226Ra chronology to calculate growth rates. The 45.5 cm long branch of M. oculata was 31 yr with an average linear growth rate of 14.4 ± 1.1 mm yr−1 (2.6 polyps per year). Despite cleaning, a correction for Mn-Fe oxide contamination was required for the oldest part of the colony; this correction corroborated our radiocarbon date of 40 yr and a mean growth rate of 2 polyps yr−1. This rate is similar to the one obtained in aquarium experiments under optimal growth conditions. For the 80 cm-long L. pertusa colony, metal-oxide contamination remained in both the middle and basal part of the coral skeleton despite cleaning, inhibiting similar age and growth rate estimates. The youngest part of the colony was free of metal oxides and this 15 cm section had an estimated a growth rate of 8 mm yr−1, with high uncertainty (~1 polyp every two to three years). We are less certain of this 210Pb growth rate estimate which is within the lowermost ranges of previous growth rate estimates. We show that 210Pb-226Ra dating can be successfully applied to determine the age and growth rate of framework-forming cold-water corals if Mn-Fe oxide deposits can be removed. Where metal oxides can be removed, large M. oculata and L. pertusa skeletons provide archives for studies of intermediate water masses with an up to annual time resolution and spanning over many decades.

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Acclimation to ocean acidification during long‐term CO 2 exposure in the cold‐water coral L ophelia pertusa

Global Change Biology ◽

10.1111/j.1365-2486.2011.02583.x ◽

2011 ◽

Vol 18 (3) ◽

pp. 843-853 ◽

Cited By ~ 155

Author(s):

Armin U. Form ◽

Ulf Riebesell

Keyword(s):

Ocean Acidification ◽

Cold Water ◽

Water Coral

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Measuring Sound at a Cold-Water Coral Reef to Assess the Impact of COVID-19 on Noise Pollution

Frontiers in Marine Science ◽

10.3389/fmars.2021.674702 ◽

2021 ◽

Vol 8 ◽

Author(s):

Laurence H. De Clippele ◽

Denise Risch

Keyword(s):

Coral Reef ◽

Coral Reefs ◽

Sea Level ◽

Cold Water ◽

Noise Pollution ◽

Ecosystem Functions ◽

Noise Levels ◽

Level Height ◽

Water Coral

This study compares the noise levels at the cold-water coral Tisler reef, before and after the closure of the border between Norway and Sweden, which occurred as a direct result of the COVID-19 pandemic. The Tisler reef is a marine protected area located under a ferry “highway” that connects Norway and Sweden. Cold-water coral reefs are recognised as being important hotspots of both biodiversity and biomass, they function as breeding and nursing grounds for commercially important fish and are essential in providing ecosystem functions. Whilst studies have shown that fishery, ocean warming, and acidification threaten them, the effects of noise pollution on cold-water coral reefs remains unstudied. To study the severity of noise pollution at the Tisler reef, a long-term acoustic recorder was deployed from 29 January 2020 until 26 May 2020. From 15 March COVID-19 lockdown measures stopped passenger vessel traffic between Norway and Sweden. This study found that the overall noise levels were significantly lower after border closure, due to reduced ferry traffic, wind speeds, and sea level height. When comparing the median hourly noise levels of before vs. after border closure, this study measured a significant reduction in the 63–125 Hz 1/3 octave band noise levels of 8.94 ± 0.88 (MAD) dB during the day (07:00:00–19:59:59) and 1.94 ± 0.11 (MAD) dB during the night (20:00:00–06:59:59). Since there was no ferry traffic during the night, the drop in noise levels at night was likely driven by seasonal changes, i.e., the reduction in wind speed and sea level height when transitioning from winter to spring. Taking into account this seasonal effect, it can be deduced that the COVID-19 border closure reduced the noise levels in the 63–125 Hz 1/3 octave bands at the Tisler reef by 7.0 ± 0.99 (MAD) dB during the day. While the contribution of, and changes in biological, weather-related and geophysical sound sources remain to be assessed in more detail, understanding the extent of anthropogenic noise pollution at the Tisler cold-water coral reef is critical to guide effective management to ensure the long-term health and conservation of its ecosystem functions.

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Global‐scale genetic structure of a cosmopolitan cold‐water coral species

Aquatic Conservation Marine and Freshwater Ecosystems ◽

10.1002/aqc.3421 ◽

2020 ◽

Author(s):

Anna Maria Addamo ◽

Karen J. Miller ◽

Vreni Häussermann ◽

Marco Taviani ◽

Annie Machordom

Keyword(s):

Genetic Structure ◽

Coral Species ◽

Cold Water ◽

Global Scale ◽

Water Coral

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High thermal tolerance of two Mediterranean cold-water coral species maintained in aquaria

Coral Reefs ◽

10.1007/s00338-013-1011-7 ◽

2013 ◽

Vol 32 (3) ◽

pp. 749-754 ◽

Cited By ~ 27

Author(s):

M. S. Naumann ◽

C. Orejas ◽

C. Ferrier-Pagès

Keyword(s):

Thermal Tolerance ◽

Coral Species ◽

Cold Water ◽

Water Coral

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In situ growth and bioerosion rates of Lophelia pertusa in a Norwegian fjord and open shelf cold-water coral habitat

PeerJ ◽

10.7717/peerj.7586 ◽

2019 ◽

Vol 7 ◽

pp. e7586 ◽

Cited By ~ 4

Author(s):

Janina V. Büscher ◽

Max Wisshak ◽

Armin U. Form ◽

Jürgen Titschack ◽

Kerstin Nachtigall ◽

...

Keyword(s):

Coral Reef ◽

Growth Rates ◽

Environmental Changes ◽

Cold Water ◽

Lophelia Pertusa ◽

Reef Growth ◽

Dead Coral ◽

Open Shelf ◽

Water Coral

Coral reef resilience depends on the balance between carbonate precipitation, leading to reef growth, and carbonate degradation, for example, through bioerosion. Changes in environmental conditions are likely to affect the two processes differently, thereby shifting the balance between reef growth and degradation. In cold-water corals estimates of accretion-erosion processes in their natural habitat are scarce and solely live coral growth rates were studied with regard to future environmental changes in the laboratory so far, limiting our ability to assess the potential of cold-water coral reef ecosystems to cope with environmental changes. In the present study, growth rates of the two predominant colour morphotypes of live Lophelia pertusa as well as bioerosion rates of dead coral framework were assessed in different environmental settings in Norwegian cold-water coral reefs in a 1-year in situ experiment. Net growth (in weight gain and linear extension) of live L. pertusa was in the lower range of previous estimates and did not significantly differ between inshore (fjord) and offshore (open shelf) habitats. However, slightly higher net growth rates were obtained inshore. Bioerosion rates were significantly higher on-reef in the fjord compared to off-reef deployments in- and offshore. Besides, on-reef coral fragments yielded a broader range of individual growth and bioerosion rates, indicating higher turnover in live reef structures than off-reef with regard to accretion–bioerosion processes. Moreover, if the higher variation in growth rates represents a greater variance in (genetic) adaptations to natural environmental variability in the fjord, inshore reefs could possibly benefit under future ocean change compared to offshore reefs. Although not significantly different due to high variances between replicates, growth rates of orange branches were consistently higher at all sites, while mortality was statistically significantly lower, potentially indicating higher stress-resistance than the less pigmented white phenotype. Comparing the here measured rates of net accretion of live corals (regardless of colour morphotype) with net erosion of dead coral framework gives a first estimate of the dimensions of both processes in natural cold-water coral habitats, indicating that calcium carbonate loss through bioerosion amounts to one fifth to one sixth of the production rates by coral calcification (disregarding accretion processes of other organisms and proportion of live and dead coral framework in a reef). With regard to likely accelerating bioerosion and diminishing growth rates of corals under ocean acidification, the balance of reef accretion and degradation may be shifted towards higher biogenic dissolution in the future.

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Long term monitoring of cold-water coral growth shows response to episodic meteorological events in the NW Mediterranean

Deep Sea Research Part I Oceanographic Research Papers ◽

10.1016/j.dsr.2020.103255 ◽

2020 ◽

Vol 160 ◽

pp. 103255

Author(s):

L. Chapron ◽

N. Le Bris ◽

X. Durrieu de Madron ◽

E. Peru ◽

P.E. Galand ◽

...

Keyword(s):

Cold Water ◽

Coral Growth ◽

Nw Mediterranean ◽

Long Term Monitoring ◽

Term Monitoring ◽

Water Coral

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Microhabitat and shrimp abundance within a Norwegian cold-water coral ecosystem

Biogeosciences ◽

10.5194/bg-10-5779-2013 ◽

2013 ◽

Vol 10 (9) ◽

pp. 5779-5791 ◽

Cited By ~ 17

Author(s):

A. Purser ◽

J. Ontrup ◽

T. Schoening ◽

L. Thomsen ◽

R. Tong ◽

...

Keyword(s):

Coral Species ◽

Cold Water ◽

Image Data ◽

Distribution Patterns ◽

Lophelia Pertusa ◽

Primnoa Resedaeformis ◽

Order Of Magnitude ◽

Paragorgia Arborea ◽

Shrimp Abundance ◽

Water Coral

Abstract. Cold-water coral (CWC) reefs are heterogeneous ecosystems comprising numerous microhabitats. A typical European CWC reef provides various biogenic microhabitats (within, on and surrounding colonies of coral species such as Lophelia pertusa, Paragorgia arborea and Primnoa resedaeformis, or formed by their remains after death). These microhabitats may be surrounded and intermixed with non-biogenic microhabitats (soft sediment, hard ground, gravel/pebbles, steep walls). To date, studies of distribution of sessile fauna across CWC reefs have been more numerous than those investigating mobile fauna distribution. In this study we quantified shrimp densities associated with key CWC microhabitat categories at the Røst Reef, Norway, by analysing image data collected by towed video sled in June 2007. We also investigated shrimp distribution patterns on the local scale (<40 cm) and how these may vary with microhabitat. Shrimp abundances at the Røst Reef were on average an order of magnitude greater in biogenic reef microhabitats than in non-biogenic microhabitats. Greatest shrimp densities were observed in association with live Paragorgia arborea microhabitat (43 shrimp m−2, SD = 35.5), live Primnoa resedaeformis microhabitat (41.6 shrimp m−2, SD = 26.1) and live Lophelia pertusa microhabitat (24.4 shrimp m−2, SD = 18.6). In non-biogenic microhabitat, shrimp densities were <2 shrimp m−2. CWC reef microhabitats appear to support greater shrimp densities than the surrounding non-biogenic microhabitats at the Røst Reef, at least at the time of survey.

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