RESUMO

This article reviews the literature involving benthic invertebrates that are cited in association with hull fouling, reporting the species that occur on the Brazilian coast and evaluating the importance of this vector for the introduction of nonindigenous and cryptogenic invertebrates in Brazil. It discusses some of the strategies that were used by the species that allowed for their overseas transport and made it easier to cross natural barriers that otherwise would have been obstacles to their dispersion. The compiled data list 343 species (65% nonindigenous and 35% cryptogenic), mainly from the northwestern Atlantic Ocean. The traveling fauna, composed mostly of cosmopolitan species (70.3%), is primarily euryhaline and marine stenohaline, with sessile and sedentary habits. After delineating the shipborne species' ecological profiles and traveling strategies and evaluating their overlapping vectors, we concluded that hull vessels were the main vector of introduction to the Brazilian coast for 89.8% of the compiled species.

Assuntos

RESUMO

Long-term monitoring program of organisms is the most recommended for understanding changing processes on reefs. The video transect method presents advantages for that. Specialists state that it is important to make sure that the recorded coverage is always the same between campaigns, so that differences in results may be entirely attributed to environmental changes. This study aimed to test the capability of implementing this requirement through tracking simulation and its validity for monitoring the benthic communities of reefs using the video transect method. Ten transects 20 m long were established in Todos os Santos Bay coral reefs. Subsequent to the first transect capture, a second diver repeated the same track, simulating two different monitoring campaigns. Data were transformed and a matrix of similarity was generated using Bray-Curtis' Index. ANOSIM analysis was performed to test the similarity of the ten transects and its repetitions. The result, R = 0.08 (P = 0.928), shows that reef monitoring using video transect, the way it is described in the literature, is appropriate, but it is important to consider some premises discussed in this work.

Assuntos

RESUMO

This study aimed to collect information on the diversity of corals and calcified hydroids of the Manuel Luiz Marine State Park (state of Maranhão, Northeast Brazil) to aid in the development of a management plan for the park. A total of 21 cnidarian species were identified, of which 16 were corals and calcified hydroids. The bathymetric and geographic distribution of each of these species was extended. This area has a rich coral fauna in relation to other parts of Brazil and is comparable in diversity to the Abrolhos Islands (Bahia State) - an unexpected result considering the region's proximity to the Amazon River Basin. Most of the specimens of corals and calcified hydroids observed were bleached.

O objetivo deste estudo foi obter informação sobre a diversidade dos corais e dos hidróides calcários do Parque Estadual Marinho do Parcel do Manuel Luiz (Estado do Maranhão, Nordeste do Brasil) para dar subsídios no desenvolvimento do plano de manejo do parque. Um total de 21 espécies de cnidários foi identificado, dos quais 16 eram corais e hidróides calcários. A distribuição batimétrica e geográfica de cada uma das espécies foram ampliadas. Esta área tem uma fauna coralínea rica com relação a outras partes do Brasil e é comparável em diversidade ao Arquipélago de Abrolhos (Estado de Bahia), um resultado inesperado considerando a proximidade da região à Bacia do Rio Amazonas. A maioria dos espécimes dos corais e dos hidróides calcários observados estava branqueada.

Assuntos

RESUMO

The skeletal variability of the coral Favia gravida, a species endemic to Brazil, was quantitatively described including populations from three locations: Tamandaré (state of Pernambuco), Abrolhos (state of Bahia), and Santa Cruz (state of Espírito Santo). Ten colonies were collected from each population and fourteen morphological characters were measured from ten corallites per colony. The results of univariate (among 14 skeletal characters, 7 showed p < 0.05) analysis provide evidence to suggest that F. gravida has considerable morphological plasticity, which may explain its ability to adapt to different ecological conditions. The species also displays polymorphism within and between colonies of each population. Intercolony variation within populations was relevant for most of the variables measured. Canonical discriminant analysis (r = 0.8648) showed that the population farthest offshore (Abrolhos) was distinct from the other two (Tamandaré and Santa Cruz), which have been affected by terrigenous sediments carried from the coast. Specimens from Santa Cruz displayed the highest degree of meandrinization.

A variação do esqueleto do coral Favia gravida, uma espécie endêmica do Brasil, foi descrita quantativamente a partir de populações de três localidades, incluindo Tamandaré (Estado de Pernambuco), Abrolhos (Estado da Bahia) e Santa Cruz (Estado do Espírito Santo). Dez colônias foram coletadas de cada população e quatorze caracteres morfológicos foram medidos de dez coralitos por colônia. Os resultados da análise univariada (dentre os 14 caracteres esqueléticos, sete apresentaram p < 0,05) fornecem evidências que sugerem que F. gravida tem uma plasticidade morfológica considerável, o que pode explicar sua habilidade para se adaptar às condições ecológicas diferentes. A espécie demonstra, também, polimorfismo dentro e entre as colônias de cada população. A variação intercolonial dentro de populações foi, também, marcante para a maioria das variáveis medidas. A análise discriminante canônica (r = 0,8648) mostrou que a população mais distante da costa (Abrolhos) foi distinta das outras duas (Tamandaré e Santa Cruz), as quais estão sendo afetadas por sedimentos terrígenos provenientes da costa. Os espécimes de Santa Cruz demonstraram o mais alto grau de meandrinização.

Assuntos