Mortality of the Antillean manatee, Trichechus manatus manatus, in Ceará State, north-eastern Brazil

Author(s):  
Ana Carolina Oliveira de Meirelles

Manatee mortality in Ceará State (north-eastern Brazil) is analysed from twenty-five strandings between 1987 and 2002. The majority of the causes were related to the ‘dependent calf’ category (83.3%). Direct human-related causes were attributed to incidental catches in fishing gear (shrimp trawling and gill-nets) (12.5%) and direct capture (4.2%). Spatial distribution was not uniform, with the highest number of strandings on the east coast. The number of strandings has increased since 1999, and the seasonal distribution showed peaks in February, March and January, in that order. The stranding of manatee calves in Ceará State seems to be indirectly related to human activities that impact coastal nursing habitats.

2003 ◽  
Vol 46 (2) ◽  
pp. 271-280 ◽  
Author(s):  
Carla Simone Pavanelli ◽  
Érica Pellegrini Caramaschi

The temporal and spatial distribution of the ichthyofauna was assessed in two streams, Caracu and São Pedro, affluents of the Rio Paraná, from March 1991 through February 1992. Samples were taken along the streams, using sieves (three sites on the Caracu and two on the São Pedro), and gill nets (two sites on the São Pedro). A total of 6,664 specimens belonging to 71 species were captured. CPE was calculated for each fishing gear. The data for cumulative frequency indicated that only the mouths of streams did not reach an asymptote. Constancy analysis showed that occasional and accessory species predominated. The spectrum of spatial diversity indicated that diversity increased toward the mouth of streams and temporal diversity increased in the high water season. The results of correspondence analysis for sieved fishes and Sørensen similarity for netted ones showed that the sites located at the same position on the streams were more similar than between adjacent sites in the same stream.


Author(s):  
Maria Danise Alves ◽  
Paul Gerhard Kinas ◽  
Miriam Marmontel ◽  
João Carlos Gomes Borges ◽  
Alexandra Fernandes Costa ◽  
...  

We estimated the abundance of Antillean manatees (Trichechus manatus manatus) through a large-scale project conducted in 2010 in north-eastern Brazil and evaluated the efficacy of an aerial survey for conservation purposes. Two observers conducted the survey via flights that maintained an altitude of 150 m and an air speed of 140 km h−1, covering over 2590.2 km2of the coastline. Strip transects were flown in a zigzag pattern. A total of 67 manatees (on- and off-effort) were recorded in 55 sightings. Historical published records of occurrence were formally incorporated using a Bayesian approach. We estimated the manatee population for north-eastern Brazil in the form of a posterior distribution with a mean of 1104 individuals and a 95% posterior probability interval ranging from 485 to 2221 individuals, which indicates high uncertainty. More large-scale studies in the region are warranted to understand temporal trends, in addition to further studies in hotspot areas, with smaller spatial scales, to reduce the coefficient of variation and to allow the use of improved techniques for monitoring the manatees. A greater emphasis on species-specific characteristics and methods to enhance detection probability (e.g. dual observers) are also recommended. The conditions prevailing along the study area were not conducive to aerial surveillance; thus, the results are not a precise estimate of the manatee population. However, these highlight the importance of conservation efforts for the Antillean manatee, considered the most endangered aquatic mammal in Brazil.


Crustaceana ◽  
2013 ◽  
Vol 86 (2) ◽  
pp. 158-181 ◽  
Author(s):  
Raúl Cruz ◽  
Carlos A. Borda

Estimates of spiny lobster stocks (Panulirus argus Latreille, 1804) represent a fundamental input for population assessment models and are, therefore, indispensable for proper management. In this study we analysed methodologies employed in the Gulf of Batabanó (Cuba) and Providencia and Santa Catalina (Colombian Caribbean) to estimate abundance (N) and stock productivity. We found evidence that the relative abundance (CPUE) for trap-like jaulones and skin diving in natural shelters was likely to remain high despite the decline in abundance (hyperstability). In contrast, the proportionality between CPUE and N was satisfactory in artificial shelters (Cuban pesqueros). Stock productivity was greater for jaulones (22 288 kg/km2) than for pesqueros (1309 kg/km2) or natural shelters (15.25 kg/km2), reflecting differences in the productive capacity of each type of fishing gear. In natural shelters the exploitable biomass is under great fishing pressure and the reproductive stock is likely to decrease. Thus, the West zone of Providencia and Santa Catalina, characterized by high-density seagrass and mangrove, should be designated a marine protection area to prevent a lobster fishing collapse. The most effective measure to revert the lobster fishing collapse in Cuba would be to ban the use of jaulones and liftable pesqueros, thereby reducing fishing intensity.


2017 ◽  
Vol 98 (7) ◽  
pp. 1619-1644 ◽  
Author(s):  
Alexandre Dias Pimenta ◽  
Bruno Garcia Andrade ◽  
Ricardo Silva Absalão

A taxonomic revision of the Nystiellidae from Brazil, including samples from the Rio Grande Rise, South Atlantic, was performed based on shell morphology. Five genera and 17 species were recognized. For the richest genus,Eccliseogyra, the three species previously recorded from Brazil were revised:E. brasiliensisandE. maracatu, previously known only from their respective type series, were re-examined. Newly available material ofE. maracatuexpanded the known geographic range of this species to off south-east Brazil.Eccliseogyra nitidais now recorded from north-eastern to south-eastern Brazil, as well as from the Rio Grande Rise. Three species ofEccliseogyraare newly recorded from the South Atlantic:E. monnioti, previously known from the north-eastern Atlantic, occurs off eastern Brazil and on the Rio Grande Rise; its protoconch is described for the first time, confirming its family allocation.Eccliseogyra pyrrhiasoccurs off eastern Brazil and on the Rio Grande Rise, andE. folinioff eastern Brazil. The genusIphitusis newly recorded from the South Atlantic.Iphitus robertsiwas found off northern Brazil, although the shells show some differences from the type material, with less-pronounced spiral keels. Additional new finds showed thatIphitus cancellatusranges from eastern Brazil to the Rio Grande Rise, and Iphitusnotiossp. nov. is restricted to the Rio Grande Rise.Narrimania, previously recorded from Brazil based on dubious records, is confirmed, including the only two living species described for the genus:N. azelotes, previously only known from the type locality in Florida, andN. concinna, previously known from the Mediterranean. A third species,Narrimania raquelaesp. nov. is described from eastern Brazil, diagnosed by its numerous and thinner cancellate sculpture. To the three species ofOpaliopsispreviously known from Brazil, a fourth species,O. arnaldoisp. nov., is added from eastern Brazil, and diagnosed by its very thin spiral sculpture, absence of a varix, and thinner microscopic parallel axial striae.Papuliscala nordestina, originally described from north-east Brazil, is recorded off eastern Brazil and synonymized withP. elongata, a species previously known only from the North Atlantic.


2001 ◽  
Vol 61 (4) ◽  
pp. 541-546 ◽  
Author(s):  
V. da BATISTA ◽  
N. N. FABRÉ

The displacement pattern of the serra, Scomberomorus brasiliensis, in North-eastern Brazil was analyzed from landing data recorded from the fleet fishing serra. Serra fishery has two seasons: from September to February (demersal species plus serra), and from March to August (almost only large amounts of serra). S. brasiliensis relative abundance increases similarly along the coast from March, but decreases first on the West coast from June. Records indicate that serra is near the coast at least until September/October in Eastern grounds. From October to March (strongest spawning season) there is no record of shoals on the coast. We concluded that the Maranhão coast is just a part of the migration circuit of S. brasiliensis that may exceed 300 nautical miles.


2015 ◽  
Vol 8 ◽  
Author(s):  
Fabilene Gomes Paim ◽  
Maria Cecília Guerrazzi ◽  
Michela Borges

In this study, we present descriptions, illustrations, comments, and bathymetric and geographic distributions of the brittle star species related to the estuary region of Camamu Bay, located in the State of Bahia, Brazil. The brittle star fauna lives on biological substrates, sand bottoms, mud and rubble in the Camamu Bay and comprises 12 species divided into five families. Almost all of them are common in the tropical and subtropical fauna of the regions of shallow water.Ophiophragmus filograneusis reported for the first time in Bahia, and nine other species are recorded for the first time in Camamu Bay:Amphipholis januarii, Amphipholis squamata, Ophiophragmus filograneus, Ophiostigma isocanthum,Ophioderma cinerea, Ophioderma januarii, Ophiactis lymani, Ophiactis savignyi andOphiocoma echinata.The results suggest that the ophiuroid assemblages are strongly affected by marine currents as well as by different kinds of bottom substrate.


Sign in / Sign up

Export Citation Format

Share Document