Percorrer por autor "Anderson, A. B."
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- Extinction risk of the endemic soft coral Phyllogorgia dilatata (Esper, 1806) in a remote island of the Brazilian coastPublication . Anderson, A. B.; Gouvêa, Lidiane; Assis, Jorge; Serrao, Ester A.; Pinheiro, H. T.; Vilar, C.; Francini-Filho, R. B.; Horta, P. A.; Bernardino, A. F.; Cordeiro, C. A. M. M.; Gomes, L. E. O.; Joyeux, J.-C.; Ferreira, C. E. L.The Brazilian endemic octocoral Phyllogorgia dilatata (elephant ear sea fan) plays a crucial ecological role in the marine ecosystems of the Brazilian coast. Our work investigates the local extinction of P. dilatata on Trindade Island, a remote oceanic island in the Southwestern Atlantic, and assesses the potential impacts of climate change on its distribution. Field surveys conducted over two years (2016-2019) revealed no live individuals of P. dilatata, with only dead peduncles remaining, marking the first observed local extinction of this species. Species distribution models (SDMs) incorporating current and historical climate data were used to estimate the species' habitat suitability and project future distribution under different climate scenarios. Results indicate that P. dilatata currently inhabits approximately 93,090 km2 of suitable area, primarily within tropical ecoregions, but faces significant habitat loss under future climate projections. By 2090-2100, models predict a 63.38 % loss of habitat under the high-emission RCP 8.5 scenario, with severe impacts on tropical regions, including Trindade Island. Environmental variables such as temperature, oxygen concentration, and salinity were identified as key drivers of the species' distribution, while non-climatic factors like seawater velocity, were also significant. The extinction on Trindade Island is attributed to a combination of historical isolation, climate change, and local anthropogenic stressors, including pollution and overfishing. The current investigation highlights the urgent need for conservation efforts, including the establishment of marine protected areas and restoration programs, to protect this vulnerable species and similar marine organisms again climate change.
- Global warming assessment suggests the endemic Brazilian kelp beds to be an endangered ecosystemPublication . Anderson, A. B.; Assis, Jorge; Batista, M. B.; Serrao, Ester; Guabiroba, H. C.; Delfino, S. D. T.; Pinheiro, H. T.; Pimentel, C. R.; Gomes, L. E. O.; Vilar, C. C.; Bernardino, A. F.; Horta, P.; Ghisolfi, R. D.; Joyeux, J.- C.Kelps are canopy-forming brown seaweed sustaining critical ecosystem services in coastal habitats, including shelter, nursery grounds, and providing food resources to a myriad of associated species. This study modeled the fundamental niche of Laminaria abyssalis along the Brazilian continental margin, an endemic species of the South Atlantic, to anticipate potential distributional range shifts under two contrasting scenarios of future environmental changes (RCP2.6 and RCP8.5). The model for fundamental niche predictions considering the "present scenario" has shown a wider potential area than the realized niche (i.e., the area where the species actually occurs) along the Brazilian coast. In both future scenarios, the models have shown niche erosion on the northern portion of the Brazilian coast and niche gains towards the south. In both scenarios, L. abyssalis populations tend to shift to deeper regions of the reef. The restricted range of occurrence (33,000 km2), intense anthropic activities along these beds (e.g., trawling fisheries, oil/gas mining, or removal for agricultural purposes) acting synergically with global warming, may drive this ecosystem to collapse faster than kelp species' ability to adapt. We propose to classify L. abyssalis as Endangered - (EN) under IUCN criteria, and highlight that long-term monitoring of kelp beds is an urgent need to develop effective conservation initiatives to protect such rare and invaluable ecosystem.
- Offshore wind farms threaten the endangered Brazilian kelp lLminaria abyssalis: a call for urgent nature-positive actionPublication . Anderson, A. B.; Opsahl-Sorteberg, H. G.; Gomes, L. E. O.; Horta, P.; Chapman, A. S.; Serrao, Ester A.; Joyeux, J-C.Constructions of offshore wind farms over 15,000 km2 are planned on the continental shelf - home to the indigenous critically endangered kelp Laminaria abyssalis and are currently under technical evaluation by the Brazilian environmental authorities (the Brazilian Institute of Environment and Renewable Natural Resources, IBAMA). Construction, maintenance and routine activity near the facilities are expected to intensify the anthropogenic pressure on the kelp’s restricted habitat (33,000 km2 ). Monitoring conducted since 2022 by the global RESTORESEAS project has highlighted the danger of a major reduction in the effective niche of L. abyssalis, raising concerns about its possible functional extinction. Immediate remapping of kelp beds combined with marine forest restoration strategies are essential to prevent irreversible loss and secure current biodiversity to face future climate changes.
- When descriptive ecology meets physiology: a study in a South Atlantic rhodolith bedPublication . Carvalho, V. F.; Silva, João; Kerr, R.; Anderson, A. B.; Bastos, E. O.; Cabral, D.; Gouvea, L. P.; Peres, L.; Martins, C. D. L.; Silveira-Andrade, V. M.; Sissini, M. N.; Horta, P. H.This study presents two years of characterization of a warm temperate rhodolith bed in order to analyse how certain environmental changes influence the community ecology. The biomass of rhodoliths and associated species were analysed during this period and in situ experiments were conducted to evaluate the primary production, calcification and respiration of the dominant species of rhodoliths and epiphytes. The highest total biomass of rhodoliths occurred during austral winter. Lithothamnion crispatum was the most abundant rhodolith species in austral summer. Epiphytic macroalgae occurred only in January 2015, with Padina gymnospora being the most abundant. Considering associated fauna, the biomass of Mollusca increased from February 2015 to February 2016. Population densities of key reef fish species inside and around the rhodolith beds showed significant variations in time. The densities of grouper (carnivores/piscivores) increased in time, especially from 2015 to 2016. On the other hand, grunts (macroinvertebrate feeders) had a modest decrease over time (from 2014 to 2016). Other parameters such as primary production and calcification of L. crispatum were higher under enhanced irradiance, yet decreased in the presence of P. gymnospora. Community structure and physiological responses can be explained by the interaction of abiotic and biotic factors, which are driven by environmental changes over time. Biomass changes can indicate that herbivores play a role in limiting the growth of epiphytes, and this is beneficial to the rhodoliths because it decreases competition for environmental resources with fleshy algae.