Increased ocean temperatures are causing mass bleaching of anemones and corals in the tropics wor... more Increased ocean temperatures are causing mass bleaching of anemones and corals in the tropics worldwide. While such heat-induced loss of algal symbionts (zooxanthellae) directly affects anemones and corals physiologically, this damage may also cascade on to other animal symbionts. Metabolic rate is an integrative physiological trait shown to relate to various aspects of organismal performance, behaviour and locomotor capacity, and also shows plasticity during exposure to acute and chronic stressors. As climate warming is expected to affect the physiology, behaviour and life-history of animals, including ectotherms such as fish, we measured if residing in bleached versus unbleached sea anemones (<i>Heteractis magnifica</i>) affected the standard (i.e. baseline) metabolic rate and behaviour (activity) of juvenile orange-fin anemonefish (<i>Amphiprion chrysopterus</i>)<i>.</i> Metabolic rate was estimated from rates of oxygen uptake (Ṁ<sub>O<...
Increased ocean temperatures are causing mass bleaching of anemones and corals in the tropics wor... more Increased ocean temperatures are causing mass bleaching of anemones and corals in the tropics worldwide. While such heat-induced loss of algal symbionts (zooxanthellae) directly affects anemones and corals physiologically, this damage may also cascade on to other animal symbionts. Metabolic rate is an integrative physiological trait shown to relate to various aspects of organismal performance, behaviour and locomotor capacity, and also shows plasticity during exposure to acute and chronic stressors. As climate warming is expected to affect the physiology, behaviour and life-history of animals, including ectotherms such as fish, we measured if residing in bleached versus unbleached sea anemones (<i>Heteractis magnifica</i>) affected the standard (i.e. baseline) metabolic rate and behaviour (activity) of juvenile orange-fin anemonefish (<i>Amphiprion chrysopterus</i>)<i>.</i> Metabolic rate was estimated from rates of oxygen uptake (Ṁ<sub>O<sub>2</sub></sub>) and the standard metabolic rate (Ṁ<sub>O<sub>2.min</sub></sub>) of anemonefish from bleached anemones was significantly higher by 8.2% compared with that of fish residing in unbleached anemones, possibly due to increased stress levels. Activity levels did not differ between fish from bleached and unbleached anemones. As Ṁ<sub>O<sub>2.min</sub></sub> reflects the minimum cost of living, the increased metabolic demands provide a likely explanation for the negative impacts of bleaching on important anemonefish life-history and fitness traits observed previously (e.g. reduced spawning frequency and lower fecundity).
This study summarises six years of spatio-temporal patterns of the discarded demersal community f... more This study summarises six years of spatio-temporal patterns of the discarded demersal community fauna recorded by onboard scientific observer program for both artisanal and industrial crustacean fisheries between 2014 and 2019, from mesophotic to aphotic depths (96 to 650 m) along the southern Humboldt Current System (28–38°S). In this period, one cold and two warm climatic events were observed during the austral summer 2014, 2015–2016 (ENSO Godzilla), and 2016–2017 (coastal ENSO), respectively. Satellite information showed that Chlorophyll-a concentration varied seasonally and latitudinally, associated with upwelling centres, while equatorial wind stress decreased southward of 36°S. Discards were composed of 108 species, dominated by finfish and molluscs. The Chilean hake Merluccius gayi was dominant and ubiquitous (occurrence, 95% of 9104 hauls), being the most vulnerable species of the bycatch. Three assemblages were identified: assemblage 1 (~200 m deep), dominated by flounders ...
Aim The mutualistic relationship between anemones and anemonefishes is one of the most iconic exa... more Aim The mutualistic relationship between anemones and anemonefishes is one of the most iconic examples of symbiosis. However, while anemonefishes have been extensively studied in terms of genetic connectivity, such information is lacking entirely for host sea anemones. Here, we provide the first information on the broad-scale population structure and phylogeographic patterns of three species of host sea anemone, Heteractis magnifica, Stichodactyla mertensii, and Entacmaea quadricolor. We evaluate if there is concordance in genetic structure across several distinct biogeographic areas within the Indo-Pacific region and to what extent the observed patterns may concur with those found for anemonefishes. Location Indo-Pacific, including the Red Sea. Taxon Heteractis magnifica, Stichodactyla mertensii, and Entacmaea quadricolor Methods Microsatellite markers and a combination of statistical methods includingBayesian clustering, Isolation by Distance (IBD), Analysis of Molecular Variance (AMOVA), and Principal Components Analysis (PCA) were used to determine population structure. The congruence among distance matrices method (CADM) was used to assess similarity in spatial genetic patterns among species. Results Significant population structure was identified in the three host anemone species. Each species is likely composed of at least two genetic clusters corresponding to two biogeographic regions, the Red Sea and the rest of the Indo-Pacific. Two of the three anemone species seem to be experiencing admixture where the two main clusters overlap (the Maldives). IBD analyses in the Red Sea revealed differences in gene flow among species, suggesting more limited dispersal potential for E. quadricolorthan forS. mertensiiand H. magnifica. Clonality is documented in S. mertensii for the first time. Main conclusions This research documents the genetic population structure for three ecologically important host sea anemones across the Indo-Pacific and provides valuable insights regarding their biogeography and evolution. Speci [...]
Group‐living animals commonly display differences in behaviour, physiology and endocrine profiles... more Group‐living animals commonly display differences in behaviour, physiology and endocrine profiles between conspecifics within the group, which are tightly linked to reproduction. Teleosts exhibit a variety of social systems, where social status, as well as sex, has been linked to different androgen and oestrogen profiles. Levels of gonadal androgen and oestrogen were investigated as a function of sex and position in a social hierarchy in free‐living individuals of the skunk anemonefish Amphiprion akallopisos, a protandrous pomacentrid fish with a size‐based dominance hierarchical social system. Plasma levels of 11‐ketotestosterone (11‐KT), testosterone (T) and 17β‐oestradiol (E2), as well as conversion ratios from T, were measured by ELISA from 111 individuals along a linear hierarchy from 38 social groups in the wild. Blood plasma levels of 11‐KT and E2 showed sex differences, being higher in males and females respectively as expected based on their role as the major androgen and o...
Increased ocean temperatures are causing mass bleaching of anemones and corals in the tropics wor... more Increased ocean temperatures are causing mass bleaching of anemones and corals in the tropics worldwide. While such heat-induced loss of algal symbionts (zooxanthellae) directly affects anemones and corals physiologically, this damage may also cascade on to other animal symbionts. Metabolic rate is an integrative physiological trait shown to relate to various aspects of organismal performance, behaviour and locomotor capacity, and also shows plasticity during exposure to acute and chronic stressors. As climate warming is expected to affect the physiology, behaviour and life-history of animals, including ectotherms such as fish, we measured if residing in bleached versus unbleached sea anemones (<i>Heteractis magnifica</i>) affected the standard (i.e. baseline) metabolic rate and behaviour (activity) of juvenile orange-fin anemonefish (<i>Amphiprion chrysopterus</i>)<i>.</i> Metabolic rate was estimated from rates of oxygen uptake (Ṁ<sub>O<...
Increased ocean temperatures are causing mass bleaching of anemones and corals in the tropics wor... more Increased ocean temperatures are causing mass bleaching of anemones and corals in the tropics worldwide. While such heat-induced loss of algal symbionts (zooxanthellae) directly affects anemones and corals physiologically, this damage may also cascade on to other animal symbionts. Metabolic rate is an integrative physiological trait shown to relate to various aspects of organismal performance, behaviour and locomotor capacity, and also shows plasticity during exposure to acute and chronic stressors. As climate warming is expected to affect the physiology, behaviour and life-history of animals, including ectotherms such as fish, we measured if residing in bleached versus unbleached sea anemones (<i>Heteractis magnifica</i>) affected the standard (i.e. baseline) metabolic rate and behaviour (activity) of juvenile orange-fin anemonefish (<i>Amphiprion chrysopterus</i>)<i>.</i> Metabolic rate was estimated from rates of oxygen uptake (Ṁ<sub>O<sub>2</sub></sub>) and the standard metabolic rate (Ṁ<sub>O<sub>2.min</sub></sub>) of anemonefish from bleached anemones was significantly higher by 8.2% compared with that of fish residing in unbleached anemones, possibly due to increased stress levels. Activity levels did not differ between fish from bleached and unbleached anemones. As Ṁ<sub>O<sub>2.min</sub></sub> reflects the minimum cost of living, the increased metabolic demands provide a likely explanation for the negative impacts of bleaching on important anemonefish life-history and fitness traits observed previously (e.g. reduced spawning frequency and lower fecundity).
This study summarises six years of spatio-temporal patterns of the discarded demersal community f... more This study summarises six years of spatio-temporal patterns of the discarded demersal community fauna recorded by onboard scientific observer program for both artisanal and industrial crustacean fisheries between 2014 and 2019, from mesophotic to aphotic depths (96 to 650 m) along the southern Humboldt Current System (28–38°S). In this period, one cold and two warm climatic events were observed during the austral summer 2014, 2015–2016 (ENSO Godzilla), and 2016–2017 (coastal ENSO), respectively. Satellite information showed that Chlorophyll-a concentration varied seasonally and latitudinally, associated with upwelling centres, while equatorial wind stress decreased southward of 36°S. Discards were composed of 108 species, dominated by finfish and molluscs. The Chilean hake Merluccius gayi was dominant and ubiquitous (occurrence, 95% of 9104 hauls), being the most vulnerable species of the bycatch. Three assemblages were identified: assemblage 1 (~200 m deep), dominated by flounders ...
Aim The mutualistic relationship between anemones and anemonefishes is one of the most iconic exa... more Aim The mutualistic relationship between anemones and anemonefishes is one of the most iconic examples of symbiosis. However, while anemonefishes have been extensively studied in terms of genetic connectivity, such information is lacking entirely for host sea anemones. Here, we provide the first information on the broad-scale population structure and phylogeographic patterns of three species of host sea anemone, Heteractis magnifica, Stichodactyla mertensii, and Entacmaea quadricolor. We evaluate if there is concordance in genetic structure across several distinct biogeographic areas within the Indo-Pacific region and to what extent the observed patterns may concur with those found for anemonefishes. Location Indo-Pacific, including the Red Sea. Taxon Heteractis magnifica, Stichodactyla mertensii, and Entacmaea quadricolor Methods Microsatellite markers and a combination of statistical methods includingBayesian clustering, Isolation by Distance (IBD), Analysis of Molecular Variance (AMOVA), and Principal Components Analysis (PCA) were used to determine population structure. The congruence among distance matrices method (CADM) was used to assess similarity in spatial genetic patterns among species. Results Significant population structure was identified in the three host anemone species. Each species is likely composed of at least two genetic clusters corresponding to two biogeographic regions, the Red Sea and the rest of the Indo-Pacific. Two of the three anemone species seem to be experiencing admixture where the two main clusters overlap (the Maldives). IBD analyses in the Red Sea revealed differences in gene flow among species, suggesting more limited dispersal potential for E. quadricolorthan forS. mertensiiand H. magnifica. Clonality is documented in S. mertensii for the first time. Main conclusions This research documents the genetic population structure for three ecologically important host sea anemones across the Indo-Pacific and provides valuable insights regarding their biogeography and evolution. Speci [...]
Group‐living animals commonly display differences in behaviour, physiology and endocrine profiles... more Group‐living animals commonly display differences in behaviour, physiology and endocrine profiles between conspecifics within the group, which are tightly linked to reproduction. Teleosts exhibit a variety of social systems, where social status, as well as sex, has been linked to different androgen and oestrogen profiles. Levels of gonadal androgen and oestrogen were investigated as a function of sex and position in a social hierarchy in free‐living individuals of the skunk anemonefish Amphiprion akallopisos, a protandrous pomacentrid fish with a size‐based dominance hierarchical social system. Plasma levels of 11‐ketotestosterone (11‐KT), testosterone (T) and 17β‐oestradiol (E2), as well as conversion ratios from T, were measured by ELISA from 111 individuals along a linear hierarchy from 38 social groups in the wild. Blood plasma levels of 11‐KT and E2 showed sex differences, being higher in males and females respectively as expected based on their role as the major androgen and o...
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Papers by Ricardo Beldade