Parrotfish

Growth rates and longevities were estimated for five major fishery species of parrotfishes (“uhu”) at Oahu, Hawai’i. All species grew rapidly with von Bertalanffy growth formula k values ≥0.4·year−1. Longevities were found to range broadly among the three small species, 4 years in Calotomus carolinus and 6 and 11 years in Scarus psittacus and Chlorurus spilurus, and to 15–20 years in Scarus rubroviolaceus and Chlorurus perspicillatus for the two large species. Age reading and growth curves for the latter two large species were validated using bomb radiocarbon dating. Median ages at sexual maturity as females (AM50) and at sex change (from female to terminal phase male, AΔ50) were estimated using logistic models. Sexual maturation occurred at 1–2 years for the small species and at 3–3.5 years in the large species. AΔ50 estimates ranged from 2 to 4 years in the small species and were about 5 and 7 years in S. rubroviolaceus and C. perspicillatus, respectively. Estimated milestones poo...

Growth rates and longevities were estimated for five major fishery species of parrotfishes (“uhu”) at Oahu, Hawai’i. All species grew rapidly with von Bertalanffy growth formula k values ≥0.4·year−1. Longevities were found to range broadly among the three small species, 4 years in Calotomus carolinus and 6 and 11 years in Scarus psittacus and Chlorurus spilurus, and to 15–20 years in Scarus rubroviolaceus and Chlorurus perspicillatus for the two large species. Age reading and growth curves for the latter two large species were validated using bomb radiocarbon dating. Median ages at sexual maturity as females (AM50) and at sex change (from female to terminal phase male, AΔ50) were estimated using logistic models. Sexual maturation occurred at 1–2 years for the small species and at 3–3.5 years in the large species. AΔ50 estimates ranged from 2 to 4 years in the small species and were about 5 and 7 years in S. rubroviolaceus and C. perspicillatus, respectively. Estimated milestones poo...

En Haïti,  le secteur de la pêche constitue une activité socio-économique ayant une place importante dans l’économie nationale pour les populations côtières comme c’est le cas de la commune de Caracol, où la pêche maritime artisanale représente l’un des secteurs clés de l’économie locale. Toutefois, un phénomène majeur appelé : surpêche risque de détériorer les stocks de ressources halieutiques. Du coup, l’objectif de ce travail de recherche consiste à montrer dans quelle mesure la surpêche a des effets bioécologiques néfastes sur les poissons-perroquets et les concombres de mer, qui sont des espèces épuratrices pour le milieu marin. D’après les données biométriques collectées sur les scaridés et les holothuries de la baie de Caracol, la surpêche constitue une menace socio-écologique, pourvu que cela entraine: la capture d’espèces de taille immature à 88% chez les scaridés et 80% chez les holothuries ; la réduction du potentiel de reproduction des espèces ; un faible taux de biomasse inférieure à la moyenne (350g pour un holothurie et 270 à 300g pour un scaridé) ; la faible Capture Par Unité d’Effort (moins de 0.30 kg) ; l’utilisation des engins de pêche illégale (sennes et nasses de petites mailles) ; l’eutrophisation des récifs coralliens par les macroalgues, dû à la diminution des poissons-perroquets qui sont les ingénieurs de l’écosystème récifal. Toutes ces caractéristiques sont liées également à la précarité sociale et économique des pêcheurs qui sans en rendent compte menacent leur moyen de survie. En termes de perspectives et en se basant sur les principes de l’approche écosystémiques des pêches nous suggérons aux autorités et autres acteurs compétents du secteur de mettre en place un plan de gestion de la pêche afin de garantir une meilleure exploitation des ressources halieutiques de la Baie de Caracol.

Parrotfishes (f. Labridae) are a unique and ubiquitous group of herbivorous reef fishes. We compared the distribution and ecosystem function (grazing and erosion) of parrotfishes across 75 reefs in Arabia. Our results revealed marked regional differences in the abundance, and taxonomic and functional composition of parrotfishes between the Red Sea, Arabian Sea, and Arabian Gulf. High densities and diversity of parrotfishes, and high rates of grazing (210% year −1) and erosion (1.57 kg m −2 year −1) characterised Red Sea reefs. Despite Arabian Sea and Red Sea reefs having broadly comparable abundances of parrotfishes, estimates of grazing (150% year −1) and erosion (0.43 kg m −2 year −1) were markedly lower in the Arabian Sea. Parrotfishes were extremely rare within the southern Arabian Gulf, and as such rates of grazing and erosion were negligible. This regional variation in abundance and functional composition of parrotfishes appears to be related to local environmental conditions.

Growth rates and longevities were estimated for five major fishery species of parrotfishes (" uhu ") at Oahu, Hawai'i. All species grew rapidly with von Bertalanffy growth formula k values ≥0.4·year −1. Longevities were found to range broadly among the three small species, 4 years in Calotomus carolinus and 6 and 11 years in Scarus psittacus and Chlorurus spilurus, and to 15–20 years in Scarus rubroviolaceus and Chlorurus perspicillatus for the two large species. Age reading and growth curves for the latter two large species were validated using bomb radiocarbon dating. Median ages at sexual maturity as females (A M50) and at sex change (from female to terminal phase male, A 50) were estimated using logistic models. Sexual maturation occurred at 1–2 years for the small species and at 3–3.5 years in the large species. A 50 estimates ranged from 2 to 4 years in the small species and were about 5 and 7 years in S. rubroviolaceus and C. perspicillatus, respectively. Estimated milestones poorly corresponded to the current minimum legal size for uhu in Hawai'i (12 in. or 30.5 cm fork length). Pooling these parrotfishes for management seems generally inappropriate, especially for the two large species. Age-based metrics are more informative than size-based metrics for these fishes.

The functional approach, using morphology and/or ecological traits, allows grouping of species that play similar roles in an ecosystem. Although species may have unique functions, some may overlap in key morphological traits, leading to similar functions (i.e. functional redundancy). To understand the functional roles of southwestern Atlantic labrids, we analyzed 21 species, focusing on morphological characteristics linked to habitat use, feeding habits and swimming ability, and further taking ontogeny into account by analyzing 3 size categories (small, medium and large) that vary in life history aspects. A comprehensive functional analysis using 11 functional traits defined according to 12 morphological measurements was performed to generate a consensus tree that segregated species into 9 functional groups. Body elongation was the most important characteristic separating parrotfishes from wrasses. Small size class was separated from medium and large size class wrasses and parrotfishes through eye size and eye positioning, respectively. Thalassoma noronhanum was grouped with invertivorous species, despite its classification as a planktivore in previous studies. This species, together with Xyrichtys splendens and Scarus zelindae, showed no size-related shifts in functional role with increasing size. Although recognized as members of different trophic guilds, different size classes of different labrid species may play similar functional roles. This suggests the need for taking size and species identity into account when measuring functional diversity and redundancy in reef ecosystems, key features for maintaining the health and robustness (i.e. resistance/resilience) of reef systems.

The parrotfish Sparisoma choati is described from the tropical eastern Atlantic Ocean. It is genetically unique and also differs from its congeners by coloration as follows: initial phase individuals and females greyish brown to greyish red, with chin and belly paler and reddish brown scales irregularly distributed along flanks resulting in a general mottled appearance ; terminal phase individuals with brownish red head and upper half of anterior two-thirds of body, ventral portion of central third of body bright yellow-green, posterior third of body dark greenish gray and dark spot on upper fifth of pectoral fin base. The new species is found in rocky reefs along the coast and oceanic islands off West Africa, from Cape Verde and Senegal south to the islands of São Tomé and Príncipe and Angola. Resumo O peixe-papagaio Sparisoma choati é descrito do Oceano Atlântico tropical oriental. Ele é geneticamente único e também difere de seus congêneres na coloração da seguinte forma: indivíduos em fase inicial e fêmeas marrom acinzentados a ver-melho acinzentados, com parte inferior da cabeça e ventre mais pálidos e escamas marrom avermelhadas irregularmente distribuídas ao logo dos flancos resultando num padrão geral de aparência de mosaico; indivíduos em fase terminal com cabeça e metade superior dos dois terços anteriores do corpo vermelho amarronzada, porção ventral do terço central do corpo verde-amarelo brilhante, terço posterior do corpo cinza esverdeado escuro e mancha escura no quinto superior da base da nadadeira peitoral. A nova espécie é encontrada em recifes rochosos ao longo da costa e ilhas oceânicas da África Ocidental, do Cabo Verde e Senegal às ilhas de São Tomé e Príncipe e Angola.

Indian parrotfish Chlorurus capistratoides live in abundance in the Indo-Pacific region. Indian parrotfish is one of seven new species found in Indonesian waters, one of 34 species of economically important parrotfish caught in the waters of Spermonde, South Sulawesi. This study aims to examine the sex ratio, gonad maturity stage, and the size at first maturity of Indian parrotfish. This research was carried out in 2014 and 2019, using samples of Indian parrotfish from the waters of the Spermonde Islands, landed by fishermen in Rajawali Makassar Fisheries Port, Makassar city. Indian parrotfish sex ratio was not balanced between male and female fish. This imbalance was covered up by the synchrony of maturity stages of the female and male. This synchrony could increase the success of the fertilization process. This synchrony explains why the population of Indian parrotfish was always there, even unbalanced in sex ratio, and because males can produce enough sperm to fertilize the eggs produced by several females. The relatively same reproduction parameters in 2014 and 2019 indicated that the reproductive parameters of Indian parrotfish had not been affected by different environmental factors of the two different years that differ in 5 years.

Dozens of marine fih species are known to form spawning aggregations, a behaviour that often increases the species vulnerability to fiheries. Therefore, it is widely recommended for aggregation sites to be considered a conservation priority, and implementation of management measures on those sites is essential. Here, we report for the fist time the reproductive behaviour of the marbled grouper Dermatolepis inermis, observed at a lower mesophotic coral ecosystem of Fernando de Noronha, an oceanic tropical archipelago in the southwestern Atlantic. The event was characterised by an aggregation of six adult fih, displaying courtship behaviour and reproductive colouration. We also recorded an aggregation of about 20 dog snappers Lutjanus jocu at the same site, but no reproductive behaviour was observed. Finally, another aggregation was observed in the island’s upper mesophotic reefs, with 25 terminal phase individuals of the Brazilian endemic parrotfih Sparisoma amplum. Our report reinforces the biological importance of mesophotic coral ecosystems, and highlights the urgent need of governmental policies for studying, monitoring, and protecting those reefs.

Fishing pressure affects the behavior of reef fish, especially of fishery-targeted species. In this context, it is critical to understand if fish behavior is preserved in no-take areas (NTAs), which are considered the best instrument for the recovery of fish stocks. Comparing the flight initiation distances (FIDs) of fish inhabiting multiple-use areas (MUAs), where fishing is allowed (including spearfishing), and NTAs is a useful approach to test whether NTAs can be effective as fish refuges. Here, we compared whether the FIDs of two target (Sparisoma axillare and Scarus trispinosus ) and one non-target (Halichoeres poeyi ) labrids are greater in the MUAs than in the NTAs. We also investigated whether group size (GS) and body size (BS) exert any effect on the FID. We sampled four MUAs and four NTAs in the Abrolhos Bank (Brazil). We found that only for the targeted species FID was shorter inside the NTAs and that the BS had a positive effect on the FID of all species. The GS and BS o...

Tropical upwelling regions appear unsuitable
for coral reef development yet the growth of true coral
reefs in these areas is well documented. Upwelling
causes highly variable water temperature, including
temperatures near and below scleractinian coral mortality
thresholds. Upwelling also raises vital plant nutrient
concentrations, increasing water column productivity and
possibly altering competitive relationships between
corals and faster growing benthic algae. This study
investigated the response of epilithic algal communities
to seasonal upwelling on coral reefs in the Gulf of
Panamá, Panamanian Pacific. A factorial caging
experiment in 2003 investigated the response of coral
reef algal communities to the factors season
(upwelling/nonupwelling), caging (reduced
herbivory/ambient herbivory) and nutrients (nutrient
enrichment/ambient nutrient). Over both three month
seasonal trials the factors caging and nutrients were
nonsignificant, but the caging treatment developed a
higher mean ash-free biomass (AFB) in the upwelling
season. Overall the season factor was significant (p <
0.0002), indicating that production was greater in the
upwelling versus the nonupwelling season (mean AFB of
2.1 mg/cm2 and 1.2 mg/cm2, respectively). The
seasonal effect was not apparent on uncaged plates
exposed to ambient levels of herbivore grazing indicating
that under normal upwelling and nonupwelling
conditions herbivores are able to control the increased
algal production. Thus, it appears that herbivores play a
critical role in controlling biomass increases in coral reef
algae exposed to upwelling conditions and may limit the
ability of algae to compete with coral even in suboptimal
coral reef environments.