João P. Barreiros

Length–weight relationships for 21 coastal fish species of the Azores, north-eastern Atlantic

Abstract Length–weight relationships were estimated for 21 coastal fish species of the Azores, namely Abudefduf luridus, Bothus podas, Chromis limbata, Coris julis, Diplodus sargus, Echiichthys vipera, Gaidropsarus guttatus, Labrus bergylta, Mullus surmuletus, Phycis phycis, Pomatomus saltator, Sarda sarda, Scorpaena maderensis, Scorpaena notata, Seriola rivoliana, Serranus atricauda, Sparisoma cretense, Sphyraena viridensis, Synodus saurus, Thalassoma pavo and Trachinotus ovatus . Significant length–weight relationships were found for all species. Sexual dimorphism did not affect the length–weight relationships, except in the cases of S. cretense and C. julis . Length–length equations for converting size measurements (standard length (SL) and fork length (FL) to total length (TL)) are also presented for all fish species.

Reproductive biology of the dusky grouper Epinephelus marginatus (Lowe, 1834)

Este trabalho trata sobre a biologia reprodutiva da garoupa verdadeira, Epinephelus marginatus (Lowe, 1834) um peixe teleosteo pertencente a familia Serranidae, hermafrodita protoginico e caracteristico do litoral rochoso, que vive desde aguas rasas ate os 200 m de profundidade. As amostragens foram realizadas nas ilhas que compoem a Reserva Biologica Marinha do Arvoredo (SC) e ilhas costeiras proximas da regiao de Florianopolis entre marco de 1998 e maio de 2000. Dados de coletas de juvenis em pocas de mares foram utilizados visando relacionar a sua ocorrencia nestes ambientes com o periodo de pos-reproducao. Procedeu-se a analise histologica de 109 exemplares, a partir da qual foram descritas as alteracoes histologicas nas gonadas ao longo do seu ciclo sexual e foram estabelecidas as escalas de maturacao. Desta forma determinou-se um tamanho de primeira maturacao para as femeas (L50=470 mm; r2=0,99). O comportamento dos valores dos indices calculados (Indice Hepatossomatico (IHS) e Indice Gonadossomatico (IGS)) elucidou um periodo reprodutivo com maturacao das gonadas ao longo dos meses de primavera, vindo a desovar na estacao do verao, sendo nitida a recuperacao do figado (elevacao do IHS) no outono, pos reproducao. Calculou-se tambem a relacao peso comprimento P = 9 · 10-6 · CT 3,1149 (r2=0,998; n=246).

Diversity and seasonal changes in the ichthyofauna of rocky tidal pools from Praia Vermelha and São Roque, Santa Catarina

A survey of the tidal pool fish community was carried out between April 1998 and May 1999, at the beaches of Praia Vermelha (PV) and Sao Roque (SR), Santa Catarina, Brazil. The pool of PV was bigger and closer to the subtidal. Specimens were collected monthly at low tide, using quinaldine. In PV we collected 1287 fish belonging to 19 species and in SR 553 fish were caught corresponding to 11 species. In both pools, dominant species were Bathygobius soporator (Gobiidae), Abudefduf saxatilis (Pomacentridae), Parablennius pilicornis (Blenniidae), Gobiesox barbatulus (Gobiesocidae), Labrisomus nuchipinnis (Labrisomidae) and Epinephelus marginatus (Serranidae). Summer months had higher abundance and diversity values, and correspond to a recruitment season for both A. saxatilis and E. marginatus.

Seasonal Changes in a Sandy Beach Fish Assemblage at Canto Grande, Santa Catarina, South Brazil

Abstract A shallow-water fish assemblage, over a soft, sandy bottom, at Canto Grande, Santa Catarina, Brazil, was sampled with a beach seine. Sampling was undertaken at 3 h intervals over 24 h on a bimonthly basis between April 1996 and February 1997. There was a seasonal variation in the number of species, density of fishes and biomass with the highest values in February (38 species, 257.6 fish 1000 m−2, 2286.4 g 1000 m−2). A total of 67 species, belonging to 56 genera and 33 families were collected and the assemblage was dominated by seven species belonging to three families: Atherinella brasiliensis (Atherinidae); Brevoortia pectinata, Harengula clupeola and Sardinella brasiliensis (Clupeidae); Anchoviella lepidontostole, Cetengraulis edentulus and Lycengraulis grossidens (Engraulidae). Species diversity (H′) and equitability (J′) were medium to high throughout the year due to the low dominance. The largest change in the assemblage structure occurred between winter months (July and August) and the other seasons. None of the dominant species can be classified as a resident. Main predators were Pomatomus saltator (winter) and Trichiurus lepturus (summer). Most of the species observed were either juvenile fish or small pelagic and strongly gregarious species.

Lethal lesions and amputation caused by plastic debris and fishing gear on the loggerhead turtle Caretta caretta (Linnaeus, 1758). Three case reports from Terceira Island, Azores (NE Atlantic).

In this note we report and discuss three cases involving two serious injuries and one death on three specimens of the loggerhead turtle Caretta caretta, found in Terceira Island, Azores (NE Atlantic). Plastic debris and lost/discarded fishing gear caused these accidents. In fact, these types of marine litter are known to cause several accidents all over the world involving many taxa. However, we think that this issue has probably a much wider impact and detected cases such as those reported here are but just a small sample of the whole unknown dimension of this serious marine pollution problem.

Space–Time Distribution of the Ichthyofauna from Saco da Fazenda Estuary, Itajaí, Santa Catarina, Brazil

Abstract From July 2003 to June 2004, the physiographic characteristics of the ichthyofauna of the estuary of Saco da Fazenda were studied in four defined areas representative of the estuary. A total of 4502 individuals were captured, with 42 species, 35 genera, and 21 families. Engraulidae were the most abundant fish, and Cetengraulis edentulus dominated the captures. The species of occasional occurrence prevailed in the samplings and were represented mainly by juvenile individuals. The highest abundances occurred during the months of summer and autumn, in contrast with high biomasses in the spring and autumn; area IV contributed the largest captures. The richness indexes, diversity, and equitability presented similar flotation patterns, with high values in spring and summer. The Jaccard index revealed a greater similarity in the composition of the ichthyofauna in areas II and IV, while the lowest happened between I and IV, which is probably due to the different sizes of these areas. This paper clearly shows the relevance of this estuary, albeit strongly impacted, for recruitment of small fish mainly during summer and autumn months.

Cleaning activity among Labridae in the Azores: the rainbow wrasse Coris julis and the Azorean blue wrasse Centrolabrus caeruleus

Cleaning interactions among the rainbow wrasse Coris julis and the azorean blue wrasse Centrolabrus caeruleus are presented with photographic registers, as well as the first record of the latter cleaning conspecifics from Azorean shallow rocky reefs.

Rocky reef fish community structure in two Azorean islands (Portugal) central North Atlantic

The community structure of shallow rocky reef fish fauna of the Azores Archipelago is described from underwater visual censuses carried out at eight areas (Terceira and Corvo Islands). A total of 52 fish species from 26 different families was observed, and the ten most abundant fish corresponded to 82.7% of all fish. Trophic categories are given for observed species with comments on distribution and densities along sampled depth strata. Mean densities along sampled strata were tested for significant differences. Sparidae, Labridae and Carangidae were the most speciose families being Diplodus sargus, Pagellus acarne, Coris julis, Thalassoma pavo and Tripterygion delaisi the most abundant species that consequently also accounted for the highest densities.

Seasonality of Ichthyofauna Bycatch in Shrimp Trawls from Different Depth Strata in the Southern Brazilian Coast

ABSTRACT Rodrigues-Filho, J.L.; Branco, J.O.; Monteiro, H.S.; Verani, J.R., and Barreiros, J.P., 2015. Seasonality of ichthyofauna bycatch in shrimp trawls from different depth strata in the southern Brazilian coast. Changes in the species composition and ecological descriptors of fish assemblages in terms of abiotic factors such as depth, temperature, salinity, and granulometry were analyzed. Monthly trawls, from October 2003 to September 2004 (30 minutes each) were analyzed in two areas covering an important shrimp fishing site of the Brazilian coast. Results using bifactorial analysis of variance revealed a seasonal variation of environmental variables (p < 0.05), and granulometry analyses showed that the composition of the fishing grounds was similar—mostly sand. A total of 12,613 fish were collected: 7880 in area I and 4733 in area II. The highest values of capture in numerical abundance (catch per unit effort) occurred during winter. Fifty taxa were caught in area I, and 53 taxa were caught in area II. Both values are considered high when compared to previous studies conducted in nearby areas. Sciaenidae was the most speciose family in all samples and in both areas were dominant in number of species (37 species in area I and 42 species in area II). Cynoscion striatus was the most abundant and dominant species in both areas. Estimates of ecological descriptors, such as richness, diversity, and evenness, showed that the ichthyofauna structure was strongly influenced by climatic factors, and all values were more pronounced during fall and winter. The permutational multivariate analysis of variance demonstrated that ichthyofauna species composition differs among seasons. The Students t test applied a posteriori showed that the community composition differed (significantly) in the following comparisons: spring vs. fall (p < 0.05) and winter vs. summer (p < 0.05). According to similarity percentage analysis, changes in the community structure were mainly correlated with species classified as abundant, which occurred unevenly during the different periods. Our results show that the fish community is influenced by seasonal variations such as salinity and temperature but not by depth or sand grain sizes. RESUMO As alterações na composição específica e nos descritores ecológicos das assembleias de peixes em função dos fatores abióticos, tais como profundidade, temperatura, salinidade e granulometria, foram analisadas no presente trabalho. Arrastos mensais de trinta minutos de duração foram realizados em duas áreas com diferentes profundidades em um importante ponto de pesca camaroeira do litoral sul brasileiro. Paralelamente, registrou—se os valores de temperatura e salinidade da água, bem como foi amostrado o tipo de substrato dos fundos de pesca. A aplicação do teste t de Student demonstrou variação sazonal dessas variáveis ambientais no estudo (p < 0,05) e a análise granulométrica demonstrou que a composição dos fundos de pesca foi bastante similar, sendo composta principalmente por areia. No total foram capturados 12.613 exemplares, sendo 7.880 na área I e 4.733 na área II. Os maiores valores de captura (CPUE) ocorreram no inverno. Foram capturados 50 táxons na área I e 53 na área II, um alto valor quando comparado com estudos pretéritos em localidades próximas. A família dos sciaenideos foi a mais representativa nas coletas, predominando em ambas as áreas espécies incidentais (37 na área I e 42 na área II). Cynoscion striatus foi a espécie mais abundante e predominante em ambas as áreas. As estimativas dos descritores ecológicos, tais como a riqueza, a diversidade e equitabilidade, evidenciaram que a estrutura da ictiofauna foi fortemente influenciada pelo fator tempo e que os valores mais acentuados ocorreram no outono e inverno. A aplicação da PERMANOVA demonstrou que a composição especifica da ictiofauna diferiu entre as estações. O teste t de Student a posteriori demonstrou que a composição da comunidade na primavera diferiu do outono e inverno (p < 0,05) e que o inverno diferiu do verão. De acordo com a análise de similaridade, as alterações na estrutura das comunidades foram causadas, sobretudo, por espécies classificadas como abundantes e que ocorreram de forma desigual entre os períodos. Nossos resultados demonstraram que a comunidade ictiica foi influenciada por variações sazonais da temperatura e salinidade e não por diferenças de profundidade e granulométrica entre as áreas.

Historic and recent occurrences of pinnipeds in the Archipelago of the Azores

No abstract available