Feeding ecology of monkfish Lophius gastrophysus in the south-western Atlantic Ocean

Author(s):  
M.F.M. Valentim ◽  
E.P. Caramaschi ◽  
M. Vianna

The diet of the monkfish Lophius gastrophysus is described based on the analysis of stomach contents, for the south-western Atlantic from samples landed in the fishing port of Niteroi, Rio de Janeiro state, Brazil, from April 2004 to March 2006. Feeding intensity, measured as the presence or absence of contents in stomachs, and differences in the items' composition were analysed by sex, size-class and season. High feeding intensity predominated for females >32 cm and for males <31 cm. There was no seasonal pattern in the occurrence of full or empty stomachs. The most important category in the diet was fish with 25 identified species. Dactylopterus volitans showed the highest alimentary index value, mainly because of the feeding of juvenile monkfish. The second most important category was Mollusca, represented mainly by squid. No relationships between predator- and prey-lengths and weights were observed; but there was a tendency to consume light and small prey independently of the size of the monkfish.

Author(s):  
Ana C. T. Bonecker ◽  
Cristina De O. Dias ◽  
Marcia S. De Castro ◽  
Pedro F. De Carvalho ◽  
Adriana V. Araujo ◽  
...  

A study was conducted over eight consecutive days in February 2010 in which daily variations in the vertical distributions of heterotrophic bacteria, mesozooplankton and ichthyoplankton at 1–1200 m in the South-western Atlantic Ocean were investigated. Diurnal and nocturnal samples were collected at an oceanographic station at four regional depths: Tropical Water (TW) (1 m), South Atlantic Central Water (SACW) (250 m), Antarctic Intermediate Water (AAIW) (800 m) and Upper Circumpolar Deep Water (UCDW) (1200 m). Bacterial, mesozooplankton and larval fish densities significantly differed between sample depths but not between sampling tow times. In total, 154 zooplankton species and 18 larval fish species were identified. The highest number of taxa was obtained from the night-time TW trawls. This depth zone had the highest densities of mesozooplankton, larval fish and bacterioplankton (auto and heterotrophic), associated with the highest temperature and salinity and the lowest inorganic nutrient concentrations. Two sample groups were identified based on their mesozooplankton and larval fish compositions: night-time TW and other water masses (daytime TW, SACW, AAIW and UCDW). Thirty-two indicator species were detected in night-time TW. The copepod Nullosetigera impar was, to the best of our knowledge, identified for the first time on the Brazilian coast. Our results showed significant variability in the abundance and vertical distribution of mesozooplankton, bacterioplankton and larval fish along the water column in an oceanic area. We have provided new data and insights on the composition and vertical distribution of mesozooplankton, larval fish and bacterioplankton in deep waters in the South-western Atlantic Ocean.


Zootaxa ◽  
2004 ◽  
Vol 630 (1) ◽  
pp. 1 ◽  
Author(s):  
CARLOS D. PÉREZ ◽  
MAURICIO O. ZAMPONI

The present study deals with six new records of octocoral species (two alcyoniid soft corals and four primnoid gorgonians) for the south western Atlantic Ocean. These new records, mainly for the gorgonians, improves the knowledge of their present distribution. The species Thouarella koellikeri and Dasystenella acanthina have their known distribution widened, showing in the first case a continuous bioceanic distribution (south east Pacific south west Atlantic). The species of the genus Primnoella, P. biserialis and P. compressa, widen their distributional range tending to a geographical continuity along the south eastern coasts of the American continent, avoiding the zoogeographic barrier constituted by the R o de la Plata.


2020 ◽  
Vol 96 (3) ◽  
pp. 601-616
Author(s):  
Federico Mas ◽  
Rodrigo Forselledo ◽  
Andrés Domingo ◽  
Oscar Pin ◽  
Pablo Troncoso ◽  
...  

2019 ◽  
Vol 99 (5) ◽  
pp. 1231-1236
Author(s):  
Giovanna Corrêa e Figueiredo ◽  
Samara Cazzoli y Goya ◽  
Marcos César de Oliveira Santos

AbstractUrbanization and intense vessel traffic in coastal areas are obstacles for right whales when selecting breeding and calving grounds. Human activities might be the main cause for the recently observed drop in right whale sightings along the south-eastern coast of Brazil. Information concerning the biology and the activities that can potentially affect the presence of individuals along the coast are essential for management purposes, as well as for the recovery of the species stocks after a period of whaling pressure. This study correlated the occurrence of right whales in the northern limit of the breeding ground in the South-western Atlantic Ocean with local geomorphology, degree of urbanization and oceanographic features to better identify suitable areas for use by these whales. The study area was divided into 14 sub-areas based on local coastal geomorphology and discharge of large rivers. The following five ranking criteria were applied to each sub-area: presence of whaling stations and whaling activity in the past; presence and activity of ports; protection from swell, coastal slope and composition of the bottom substrate. The sub-areas that offered conditions conducive to the presence of right whales received higher scores. The proposed criteria were validated by overlapping the ranking scores with the records of right whales sighted in each sub-area. In south-eastern Brazil, protected areas with sandy bottom and gentle slope were associated with more sightings of female-calf pairs. The criteria can be used as a primary diagnostic indicating suitable sub-areas for right whales in poorly known breeding grounds.


2016 ◽  
Vol 89 (3) ◽  
pp. 1873-1879 ◽  
Author(s):  
C. L. S. Sampaio ◽  
J. Santander-neto ◽  
T. L. A. Costa

2020 ◽  
Vol 15 (1) ◽  
Author(s):  
Koshal Kumar ◽  
Anita Rawat Rana ◽  
Chandra Bhanu Kotnala

In this paper the feeding index (FI), Gastro somatic index (GaSI) and Food Prevalence Index (FPI) of freshwater prawn Macrobrachium assamense peninsulare were evaluated to assess the quantity and quality of food preferred by it in the Rawasan stream. A total of 401 prawns were collected during a span of two years from five selected sites in the Rawasan stream of Garhwal in Central Himalaya, India from August 2013 to July 2015. Collected prawns were in the size range of 20-75 mm in males and 24-65 mm in females in total length. The stomach contents of 10 collected specimens were examined monthly and observed that 35% of the stomach was full or semifull and 15% stomach were empty. The highest Gastro somatic value was obtained 2.95±0.80 during June in the male and 3.25±0.44 during May in the female. After that, it gradually decreased in both the sexes and is repeated in cyclic patterns each year. More or less a similar trend was reported in the feeding index value during the study which indicates a significant relationship between feeding intensity and Gastro somatic index. The highest Food Prevalence Index (FPI) was seen as fragments of animal matter in both sexes, which was (88.48) in male and (58.26) in female prawns and the lowest FPI value was sand and debris (7.9 and 5.7) in male and female prawn respectively. The main food items were the fragment of plants as well as animals, diatoms, algae, and sand. Overall, the results show that this prawn is selectively abstemious.


2018 ◽  
Vol 92 (4) ◽  
pp. 1082-1089 ◽  
Author(s):  
Y. V. Niella ◽  
L. A. G. Duarte ◽  
V. R. Bandeira ◽  
O. Crespo ◽  
D. Beare ◽  
...  

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