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1.
Ecology ; 104(3): e3966, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36571283

RESUMO

The TimeFISH database provides the first public time-series dataset on reef fish assemblages in the southwestern Atlantic (SWA), comprising 15 years of data (2007-2022) based on standardized Underwater Visual Censuses (UVCs). The rocky reefs covered by our dataset are influenced by pronounced seasonal cycles of ocean temperatures with warm tropical waters from the Brazil Current in the summer (~27°C) and colder waters from the La Plata River Plume discharge and upwelling from the South Atlantic Central Water in the winter (~18°C). These oceanographic conditions characterize this area as the southernmost tropical-subtropical climatic transition zone in the Atlantic Ocean. As a result, reef fish assemblages are comprised of both tropical and subtropical species. All records included in TimeFISH were collected using UVCs, a nondestructive method that allows the estimation of fish species richness, abundance, and body size distributions. UVCs were performed through 40 m2 belt transects by scuba diving in nine locations along the southern Brazilian coast (25-29°S). Four of these locations lie within the boundaries of the no-entry Arvoredo Marine Biological Reserve, where fishing and recreational activities are forbidden, and the remaining locations are unprotected from these activities. During each belt transect, a diver swam at a constant depth above and parallel to the reef, identifying fish species, counting the number of individuals, and estimating the total body length (Lt in cm) of all detected individuals. All fish individuals in the water column (up to 2 m above the substratum) and at the bottom were targeted. In total, 202,965 individuals belonging to 163 reef fish species and 53 families were recorded across 1857 UVCs. All survey campaigns were funded by either public or mixed capital (private-public) sources, including seven grants from the Brazilian federal and Santa Catarina state governments. Part of the data has already been used in multiple MS.c. and Ph.D. theses and scientific articles. TimeFISH represents an important contribution for future studies aiming to examine temporal and spatial variations of reef fish assemblages in transition zones. No copyright restrictions apply to the use of this data set, other than citing this publication.


Assuntos
Clima Tropical , Água , Animais , Estações do Ano , Tamanho Corporal , Brasil , Peixes , Recifes de Corais , Biodiversidade , Ecossistema
2.
Science ; 375(6578): 336-340, 2022 01 21.
Artigo em Inglês | MEDLINE | ID: mdl-35050678

RESUMO

The global decline of coral reefs has led to calls for strategies that reconcile biodiversity conservation and fisheries benefits. Still, considerable gaps in our understanding of the spatial ecology of ecosystem services remain. We combined spatial information on larval dispersal networks and estimates of human pressure to test the importance of connectivity for ecosystem service provision. We found that reefs receiving larvae from highly connected dispersal corridors were associated with high fish species richness. Generally, larval "sinks" contained twice as much fish biomass as "sources" and exhibited greater resilience to human pressure when protected. Despite their potential to support biodiversity persistence and sustainable fisheries, up to 70% of important dispersal corridors, sinks, and source reefs remain unprotected, emphasizing the need for increased protection of networks of well-connected reefs.


Assuntos
Biodiversidade , Conservação dos Recursos Naturais , Recifes de Corais , Pesqueiros , Peixes , Distribuição Animal , Animais , Teorema de Bayes , Biomassa , Ecossistema , Humanos , Modelos Estatísticos
3.
Glob Chang Biol ; 26(2): 557-567, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31697006

RESUMO

Rapid intensification of environmental disturbances has sparked widespread decline and compositional shifts in foundation species in ecosystems worldwide. Now, an emergent challenge is to understand the consequences of shifts and losses in such habitat-forming species for associated communities and ecosystem processes. Recently, consecutive coral bleaching events shifted the morphological makeup of habitat-forming coral assemblages on the Great Barrier Reef (GBR). Considering the disparity of coral morphological growth forms in shelter provision for reef fishes, we investigated how shifts in the morphological structure of coral assemblages affect the abundance of juvenile and adult reef fishes. We used a temporal dataset from shallow reefs in the northern GBR to estimate coral convexity (a fine-scale quantitative morphological trait) and two widely used coral habitat descriptors (coral cover and reef rugosity) for disentangling the effects of coral morphology on reef fish assemblages. Changes in coral convexity, rather than live coral cover or reef rugosity, disproportionately affected juvenile reef fishes when compared to adults, and explained more than 20% of juvenile decline. The magnitude of this effect varied by fish body size with juveniles of small-bodied species showing higher vulnerability to changes in coral morphology. Our findings suggest that continued large-scale shifts in the relative abundance of morphological groups within coral assemblages are likely to affect population replenishment and dynamics of future reef fish communities. The different responses of juvenile and adult fishes according to habitat descriptors indicate that focusing on coarse-scale metrics alone may mask fine-scale ecological responses that are key to understand ecosystem functioning and resilience. Nonetheless, quantifying coral morphological traits may contribute to forecasting the structure of reef fish communities on novel reef ecosystems shaped by climate change.


Assuntos
Antozoários , Animais , Mudança Climática , Recifes de Corais , Ecossistema , Peixes
4.
J Insect Physiol ; 57(6): 801-8, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21420973

RESUMO

The fate of vicilins ingested by Callosobruchus maculatus and the physiological importance of these proteins in larvae and adults have been recently investigated. Vicilins have been demonstrated to be absorbed through the midgut epithelium, circulate in their trimeric form in the haemolymph and are deposited in the fat body. In fat body cells of both sexes, vicilins are partially hydrolyzed and the fragments are eventually deposited in the eggs. Tracking the fate of FITC-labelled vicilins in adult males revealed that the labelled vicilin fragments were also detected in oöcytes and eggs, when the males copulated with non-labelled females. Based on the results presented here, we propose that following absorption, vicilins accumulate in the fat body, where they are partially degraded. These peptides are retained throughout the development of the males and are eventually sequestered by the gonads and passed to the female gonads during copulation. It is possible that accumulation in the eggs is a defensive strategy against pathogen attack, as these peptides are known to have antimicrobial activity. The contribution of vicilin-derived peptides from seminal fluids may be an investment that helps to increase the offspring survival. This study provides additional insights into the possible contributions of males to female fecundity following copulation in C. maculatus.


Assuntos
Besouros/fisiologia , Fabaceae/parasitologia , Oócitos/metabolismo , Peptídeos/metabolismo , Proteínas de Armazenamento de Sementes/metabolismo , Sementes/metabolismo , Espermatozoides/metabolismo , Animais , Copulação , Fabaceae/química , Fabaceae/metabolismo , Corpo Adiposo/metabolismo , Feminino , Hemolinfa/metabolismo , Masculino , Peptídeos/química , Sementes/química , Sementes/parasitologia
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