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Sarasota, FL, United States

Correa L.,University of Alaska Fairbanks | Castellini J.M.,University of Alaska Fairbanks | Wells R.S.,Sarasota Dolphin Research Program | O'Hara T.,University of Alaska Fairbanks
Environmental Toxicology and Chemistry | Year: 2013

Total mercury and selenium concentrations ([THg], [Se]) in serum, plasma, whole blood, and packed cells were examined in a resident population of free-ranging bottlenose dolphins (Tursiops truncatus) from Sarasota Bay, Florida, USA. The authors determined how these elements partition in blood and assess compartment-specific associations. Determining the distribution of Se and THg can provide physiologic insight into potential association of Hg with selenol-containing biomolecules (e.g., antioxidants) in blood compartments. Concentrations of THg were ranked serum Source

Tyson R.B.,Duke University | Tyson R.B.,Sarasota Dolphin Research Program | Friedlaender A.S.,Duke University | Friedlaender A.S.,Oregon State University | Nowacek D.P.,Duke University
Animal Behaviour | Year: 2016

Optimal foraging theory (OFT) suggests that air-breathing diving animals should minimize costs associated with feeding under water (e.g. travel time, oxygen loss) while simultaneously maximizing benefits gained from doing so (e.g. foraging time, energy gain). Humpback whales, Megaptera novaeangliae, foraging along the Western Antarctic Peninsula appear to forage according to OFT, but the direct costs and benefits in terms of their behaviours (e.g. allocation of time) have not been examined. We compared the foraging behaviour of humpback whales in this region inferred from multisensor high-resolution recording tags to their behaviour predicted by OFT time allocation models assuming the following currencies were being maximized: (1) the proportion of time spent foraging, (2) the net rate of energetic gain and/or (3) the ratio of energy gained to energy expended (i.e. efficiency). Model predictions for all three currencies were similar, suggesting any of these OFT models were suitable for comparison with the observed data. However, agreement between observed and optimal behaviours varied widely depending on the physiological and behavioural values used to derive optimal predictions, highlighting the need for an improved understanding of cetacean physiology. Despite this, many of the theoretical OFT predictions were supported: shallow dives (i.e. <100 m), which were short and executed most frequently, yielded the highest proportions of foraging time, and the greatest net rates of energy gain and were the most efficient. In addition, dive and foraging times increased in duration rapidly with increasing maximum dive depths to approximately 100 m and then at lower rates with deeper dives. Our findings offer a thorough examination of the applicability of time allocation OFT models to the behaviours of a large, air-breathing, diving predator and provide insights into the foraging ecology and physiology of humpback whales in the Western Antarctic Peninsula. © 2016 The Association for the Study of Animal Behaviour. Source

Adimey N.M.,U.S. Fish and Wildlife Service | Hudak C.A.,Right Whale Research Program | Powell J.R.,National Oceanic and Atmospheric Administration | Bassos-Hull K.,Sarasota Dolphin Research Program | And 4 more authors.
Marine Pollution Bulletin | Year: 2014

Documenting the extent of fishery gear interactions is critical to wildlife conservation efforts, especially for reducing entanglements and ingestion. This study summarizes fishery gear interactions involving common bottlenose dolphins (Tursiops truncatus truncatus), Florida manatees (Trichechus manatus latirostris) and sea turtles: loggerhead (Caretta caretta), green turtle (Chelonia mydas), leatherback (Dermochelys coriacea), hawksbill (Eretmochelys imbricata), Kemp's ridley (Lepidochelys kempii), and olive ridley (Lepidochelys olivacea) stranding in Florida waters during 1997-2009. Fishery gear interactions for all species combined were 75.3% hook and line, 18.2% trap pot gear, 4.8% fishing nets, and 1.7% in multiple gears. Total reported fishery gear cases increased over time for dolphins (p<. 0.05), manatees (p<. 0.01), loggerheads (p<. 0.05) and green sea turtles (p<. 0.05). The proportion of net interaction strandings relative to total strandings for loggerhead sea turtles increased (p<. 0.05). Additionally, life stage and sex patterns were examined, fishery gear interaction hotspots were identified and generalized linear regression modeling was conducted. © 2014. Source

DeClue A.E.,University of Missouri | Yu D.-H.,Chonnam National University | Prochnow S.,University of Missouri | Axiak-Bechtel S.,University of Missouri | And 7 more authors.
Veterinary Journal | Year: 2014

Opioids alter immune and apoptotic pathways in several species. They are commonly used in companion animals affected with infectious and/or inflammatory disease, but the immunomodulatory and apoptotic effects of these drugs in dogs are relatively unknown. The aim of the present study was to evaluate the effects of morphine, buprenorphine and fentanyl on canine phagocyte function, oxidative burst capacity, leukocyte cytokine production, and lymphocyte apoptosis. Blood from six healthy adult dogs was incubated in the presence or absence of morphine (200 ng/mL), buprenorphine (10 ng/mL) or fentanyl (10 ng/mL) for 3 h (phagocytic function; cytokine production) or 8 h (apoptosis). Neutrophil phagocytosis of opsonized Escherichia coli, respiratory burst capacity after stimulation with opsonized E. coli or phorbol 12-myristate 13-acetate (PMA), and Annexin V-FITC staining of apoptotic lymphocytes were evaluated using flow cytometry. Leukocyte production of tumor necrosis factor (TNF)-α, interleukin (IL)-6 and IL-10 was assessed after incubation with lipopolysaccharide (LPS), lipoteichoic acid (LTA) or peptidoglycan.Morphine promoted a more intense respiratory burst. Morphine, buprenorphine and fentanyl all promoted LPS- or LTA-induced TNF-α and IL-10 production. However, the opioids tested did not alter TNF-α:IL-10 ratios. Morphine, buprenorphine and fentanyl all inhibited neutrophil apoptosis, an effect that was not concentration dependent in nature. These data indicate that opioids alter immune and apoptotic pathways in dogs. The possible effects of opioids on immune and cellular responses should be considered when designing studies and interpreting outcomes of studies involving administration of opioids in dogs. © 2014. Source

Janik V.M.,University of St. Andrews | King S.L.,University of St. Andrews | Sayigh L.S.,Woods Hole Oceanographic Institution | Wells R.S.,Sarasota Dolphin Research Program
Marine Mammal Science | Year: 2013

Bottlenose dolphins (Tursiops truncatus) have individually distinctive signature whistles. Each individual dolphin develops its own unique frequency modulation pattern and uses it to broadcast its identity. However, underwater sound localization is challenging, and researchers have had difficulties identifying signature whistles. The traditional method to identify them involved isolating individuals. In this context, the signature whistle is the most commonly produced whistle type of an animal. However, most studies on wild dolphins cannot isolate animals. We present a novel method, SIGnature IDentification (SIGID), that can identify signature whistles in recordings of groups of dolphins recorded via a single hydrophone. We found that signature whistles tend to be delivered in bouts with whistles of the same type occurring within 1-10 s of each other. Nonsignature whistles occur with longer or shorter interwhistle intervals, and this distinction can be used to identify signature whistles in a recording. We tested this method on recordings from wild and captive bottlenose dolphins and show thresholds needed to identify signature whistles reliably. SIGID will facilitate the study of signature whistle use in the wild, signature whistle diversity between different populations, and potentially allow signature whistles to be used in mark-recapture studies. © 2012 by the Society for Marine Mammalogy. Source

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