Effects of tourism-related provisioning on the trophic signatures and movement patterns of an apex predator, the Caribbean reef shark

2011 ◽  
Vol 144 (2) ◽  
pp. 859-865 ◽  
Author(s):  
Aleksandra Maljković ◽  
Isabelle M. Côté
2017 ◽  
Vol 67 (3-4) ◽  
pp. 191-208 ◽  
Author(s):  
Marcella P. Uchoa ◽  
Craig P. O’Connell ◽  
Thomas J. Goreau

Healthy coral reefs are biologically diverse and provide vital ecosystem services. However, decreasing water quality and global warming are key contributors to coral reef decline, which poses substantial environmental threats. In response to this degradation, an innovative coral reef restoration technology, called Biorock, utilizes weak direct current electric fields to cause limestone deposition on conductive materials, inevitably inducing prolific coral reef growth. Although expediting coral growth, research on how the associated electric fields may impact the behavioural patterns of teleosts and/or organisms (i.e. elasmobranchs) possessing electroreception capabilities is lacking. Therefore, we studied the behavioural responses of two shark species, the bull shark (Carcharhinus leucas) and the Caribbean reef shark (Carcharhinus perezi) and multiple teleost species towards weak direct current electric fields in Bimini, Bahamas. Generalized linear mixed model analyses based on 90 trials illustrate that both the feeding and avoidance behaviors of C. leucas and C. perezi were significantly associated with treatment type, with the weak experimental electrode treatments resulting in the greatest quantity of avoidances and fewest feedings for both species. However, data analyses illustrate that teleost feeding behavior was not observably impacted by experimental treatments. Although the Biorock technology exhibits promise in coral reef restoration, the findings from this study illustrate a need for future large-scale studies assessing shark behavioral patterns around these devices, since the deterrence of apex predators may impact ecosystem balance.


2021 ◽  
Vol 6 (9) ◽  
pp. 2662-2664
Author(s):  
Austin J. Gallagher ◽  
Oliver N. Shipley ◽  
Bo Reese ◽  
Vijender Singh

Author(s):  
Edward J. Brooks ◽  
John W. Mandelman ◽  
Katherine A. Sloman ◽  
Stephanie Liss ◽  
Andy J. Danylchuk ◽  
...  

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Oliver N. Shipley ◽  
Cheng-Shiuan Lee ◽  
Nicholas S. Fisher ◽  
James K. Sternlicht ◽  
Sami Kattan ◽  
...  

AbstractOver the last century anthropogenic activities have rapidly increased the influx of metals and metalloids entering the marine environment, which can bioaccumulate and biomagnify in marine top consumers. This may elicit sublethal effects on target organisms, having broad implications for human seafood consumers. We provide the first assessment of metal (Cd, Pb, Cr, Mn, Co, Cu, Zn, As, Ag, and THg) and metalloid (As) concentrations in the muscle tissue of coastal sharks from The Bahamas. A total of 36 individual sharks from six species were evaluated, spanning two regions/study areas, with a focus on the Caribbean reef shark (Carcharhinus perezi), and to a lesser extent the tiger shark (Galeocerdo cuvier). This is due their high relative abundance and ecological significance throughout coastal Bahamian and regional ecosystems. Caribbean reef sharks exhibited some of the highest metal concentrations compared to five other species, and peaks in the concentrations of Pb, Cr, Cu were observed as individuals reached sexual maturity. Observations were attributed to foraging on larger, more piscivorous prey, high longevity, as well a potential slowing rate of growth. We observed correlations between some metals, which are challenging to interpret but may be attributed to trophic level and ambient metal conditions. Our results provide the first account of metal concentrations in Bahamian sharks, suggesting individuals exhibit high concentrations which may potentially cause sublethal effects. Finally, these findings underscore the potential toxicity of shark meat and have significant implications for human consumers.


Author(s):  
KI Flowers ◽  
EA Babcock ◽  
YP Papastamatiou ◽  
ME Bond ◽  
N Lamb ◽  
...  

1992 ◽  
Vol 6 ◽  
pp. 43-43
Author(s):  
Ann F. Budd ◽  
Thomas A. Stemann ◽  
Kenneth G. Johnson

Study of the stratigraphic ranges of reef coral species in scattered sequences (Dominican Republic, Bahamas, Costa Rica, Jamaica, and Florida) suggests that a major episode of faunal turnover occurred in the Caribbean region between early Pliocene and mid Pleistocene time. In a data set composed of all reef corals except the families Mussidae and Oculinidae and the genera Cladocora and Madracis, approximately 90% of the Mio-Pliocene fauna, composed of as many as 65–70 species, became extinct during this time interval. Ten of 27 genera became extinct. Despite the high numbers of extinctions, the total number of species in the Caribbean reef coral fauna dropped only slightly over the time interval, due to similar numbers of originations and extinctions in the fauna. With one possible exception, new species arose in surviving genera, and no new genera formed.Although similar numbers of species became extinct within early Pliocene, late Pliocene, and early Pleistocene time units, shallow water communities experienced higher numbers of extinctions during the late Miocene and early Pliocene. Deeper water communities experienced higher numbers of extinctions during the late Pliocene and early Pleistocene. Species surviving the turnover episode occur in deeper water communities and belong predominantly to the family Agariciidae. Nearshore grass flat communities contain the highest number of early extinctions. No difference in extinction patterns could be detected between taxa which reproduce primarily by fragmentation and those that reproduce primarily by larval recruitment. Although originations appear evenly distributed among community types, a large number occur in Florida along the northern margin of faunal distribution.The increased extinctions in shallow water communities and increased originations in the north suggest that turnover occurred primarily in response to change in abiotic factors such as temperature and siltation, and not in response to species-area effects associated with sea level change.


1973 ◽  
Vol 145 (1) ◽  
pp. 140-149 ◽  
Author(s):  
JOHN T. LEHMAN ◽  
JAMES W. PORTER

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