Incidental capture and mortality of sea turtles in the industrial double‐rig‐bottom trawl fishery in south‐eastern Brazil

2019 ◽  
Vol 30 (2) ◽  
pp. 351-363
Author(s):  
Alicia Bertoloto Tagliolatto ◽  
Bruno Giffoni ◽  
Suzana Guimarães ◽  
Matthew H. Godfrey ◽  
Cassiano Monteiro‐Neto
Author(s):  
Ryan Knotek ◽  
Jeff Kneebone ◽  
James Sulikowski ◽  
Tobey Curtis ◽  
Joseph Jurek ◽  
...  

Abstract Thorny skate (Amblyraja radiata) remain one of the most overfished species in the Gulf of Maine (GOM) despite being designated as a prohibited (zero-possession, mandatory release) species by the New England Fishery Management Council in 2003. To better understand the extent to which discard mortality (DM) occurring after incidental capture in the GOM groundfish bottom trawl fishery may be impeding recovery, 75 individuals (55–94 cm total length, TL) were tagged with pop-up satellite archival transmitting (PSAT) tags and monitored for up to 28 days following capture under representative commercial trawl fishing practices. Data recovered from 61 PSAT-tagged skate were analysed with a longitudinal survival analysis to estimate DM and identify influential capture-related variables. DM rate was a function of TL, with larger skates (>70 cm; DM = 16.5%) experiencing lower mortality than smaller conspecifics (55–70 cm; DM = 24.5%). From our results, we estimate annual thorny skate DM in the GOM groundfish bottom trawl fishery to be 79.2 ± 0.2 mt, which accounts for <1% of the existing stock biomass in the GOM (8400 mt). This study confirms that thorny skate are relatively resilient to bottom trawl fishing practices in the GOM, and suggests that other sources of mortality may be impeding population recovery.


2015 ◽  
Vol 8 ◽  
Author(s):  
Ana Paula Madeira Di Beneditto ◽  
Jailson Fulgencio De Moura ◽  
Salvatore Siciliano

Studies of the feeding habits of sea turtles are important in identifying their feeding grounds and preferred prey, thus helping with management decisions regarding habitat protection. The present study describes, for the first time, the feeding habits of the sea turtlesCaretta carettaandLepidochelys olivaceain Rio de Janeiro State, south-eastern Brazil (22°06′S–22°55′S). The stomach contents of fiveC. carettaand fiveL. olivacearecovered between 2009 and 2010 were analysed to identify the prey species. A common feeding pattern was noted for both species, with bottom-dwelling prey (fish, crustaceans, molluscs and echinoderms), common in shallow environments, constituting the main food items. All fish and brachyuran crustacean species identified in the stomach contents were by-catch in small-scale shrimp fisheries that operate along the study area. The coastal waters of Rio de Janeiro State represent a new feeding ground forL. olivacea, expanding its preferential habitat during the non-reproductive period. The results provide strong evidence for the likelihood that sea turtles are interacting with fisheries due to an overlapping between feeding and fishery grounds. An evaluation of carcasses washed up on beaches is needed for a better understanding of the effects on the population dynamics of sea turtles.


2008 ◽  
Vol 158 (2) ◽  
pp. 306-308
Author(s):  
MARCELO DA COSTA SOUZA ◽  
MARLI PIRES MORIM

Oryx ◽  
2014 ◽  
Vol 49 (1) ◽  
pp. 60-63 ◽  
Author(s):  
Guilherme Braga Ferreira ◽  
Marcelo Juliano Rabelo Oliveira ◽  
Rogério Cunha de Paula ◽  
Flávio Henrique Guimarães Rodrigues ◽  
Érica Daniele Cunha Carmo

AbstractThe bush dog Speothos venaticus, a rare Near Threatened South American canid that lives in packs, was thought to be extinct in Minas Gerais state, south-eastern Brazil, until recently. Here, we report four recent records of the species in Minas Gerais, the first in the state since the description of the species in 1842. All records are from the Cerrado ecosystem in the north and north-west of the state; two are from animals found dead, one from footprints and another from a camera trap. Three of the records were inside or close (< 10 km) to strict protected areas, in a region recognized as the Protected Areas Mosaic Sertão Veredas–Peruaçu, where we expect any new records of the bush dog to be found. We discuss the low probability of detecting the bush dog and the main regional threats to the species, and emphasize the need to protect large and interconnected natural areas and keep them free of domestic dogs to avoid the extinction of the bush dog in Minas Gerais.


Author(s):  
M.R. Denadai ◽  
F.B. Santos ◽  
E. Bessa ◽  
L.P. Bernardes ◽  
A. Turra

This study describes the spatio-temporal distribution, population biology, and diet of the puffer fish Lagocephalus laevigatus in Caraguatatuba Bay, south-eastern Brazil. Monthly samples were taken between August 2003 and October 2004 by trawls in two areas, south and north, at depths of 1 to 4 m. The fish were measured and their sex and reproductive stage determined. The abundance of this species was compared between areas and among months, and the items in the diet were identified and quantified. Lagocephalus laevigatus was rare in Caraguatatuba Bay, where only 199 small individuals (4.8 to 15.4 cm) were obtained in the entire study period, suggesting that this species uses the estuary as a nursery. None of the specimens of L. laevigatus captured in Caraguatatuba Bay were sexually mature. Higher densities of L. laevigatus in the bay were recorded in the south area and between October and December 2003, i.e. in the spring, suggesting that spawning may occur from late winter to spring (August through to November). The diet items consumed by L. laevigatus in Caraguatatuba Bay were, as expected from the current literature, crustaceans, mainly amphipods, and fish. However, the most-consumed item was the sea whip Leptogorgia setacea (Cnidaria). This feeding habit may be related to the presence of toxins (tetrodotoxin and saxitoxin) that are frequently found in the skin and viscera of L. laevigatus, which may be sequestered from the sea whip, which possibility still needs to be specifically evaluated.


Author(s):  
Ana Paula Madeira Di Beneditto ◽  
Salvatore Siciliano

Along the central coast of Rio de Janeiro State (22°25′S–23°00′S), south-eastern Brazil, the marine tucuxi dolphin (Sotalia guianensis) feeds on neritic prey that are distributed through the water column and are abundant all year round. The most frequently found species were the teleost fish Trichiurus lepturus, Cynoscion guatucupa, Isopisthus parvipinnis and Porichthys porossisimus. Fish species were more important than cephalopod species in the diet of the marine tucuxi. Back calculations of prey sizes indicated that they feed mainly on young specimens. The present study provided additional information on the feeding habits of the marine tucuxi dolphin.


Sign in / Sign up

Export Citation Format

Share Document