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Gunner RM, Wilson RP, Holton MD, Scott R, Arkwright A, Fahlman A, Ulrich M, Hopkins P, Duarte C, Eizaguirre C. Activity of loggerhead turtles during the U-shaped dive: insights using angular velocity metrics. ENDANGER SPECIES RES 2021. [DOI: 10.3354/esr01125] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
Understanding the behavioural ecology of endangered taxa can inform conservation strategies. The activity budgets of the loggerhead turtle Caretta caretta are still poorly understood because many tracking methods show only horizontal displacement and ignore dives and associated behaviours. However, time-depth recorders have enabled researchers to identify flat, U-shaped dives (or type 1a dives) and these are conventionally labelled as resting dives on the seabed because they involve no vertical displacement of the animal. Video- and acceleration-based studies have demonstrated this is not always true. Focusing on sea turtles nesting on the Cabo Verde archipelago, we describe a new metric derived from magnetometer data, absolute angular velocity, that integrates indices of angular rotation in the horizontal plane to infer activity. Using this metric, we evaluated the variation in putative resting behaviours during the bottom phase of type 1a dives for 5 individuals over 13 to 17 d at sea during a single inter-nesting interval (over 75 turtle d in total). We defined absolute resting within the bottom phase of type 1a dives as periods with no discernible acceleration or angular movement. Whilst absolute resting constituted a significant proportion of each turtle’s time budget for this 1a dive type, turtles allocated 16-38% of their bottom time to activity, with many dives being episodic, comprised of intermittent bouts of rest and rotational activity. This implies that previously considered resting behaviours are complex and need to be accounted for in energy budgets, particularly since energy budgets may impact conservation strategies.
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Affiliation(s)
- RM Gunner
- Swansea Lab for Animal Movement, Biosciences, College of Science, Swansea University, Swansea SA2 8PP, UK
| | - RP Wilson
- Swansea Lab for Animal Movement, Biosciences, College of Science, Swansea University, Swansea SA2 8PP, UK
| | - MD Holton
- Swansea Lab for Animal Movement, Biosciences, College of Science, Swansea University, Swansea SA2 8PP, UK
| | - R Scott
- GEOMAR Helmholtz Centre for Ocean Research, Kiel, Düsternbrooker Weg 20, 24105 Kiel, Germany
- Natural Environmental Research Council, Polaris House, North Star Avenue, Swindon SN2 1FL, UK
| | - A Arkwright
- Swansea Lab for Animal Movement, Biosciences, College of Science, Swansea University, Swansea SA2 8PP, UK
- L’Oceanogràfic, Ciutat de les Arts i de les Ciències, Carrer d’Eduardo Primo Yúfera, 1B, 46013 Valencia, Spain
| | - A Fahlman
- L’Oceanogràfic, Ciutat de les Arts i de les Ciències, Carrer d’Eduardo Primo Yúfera, 1B, 46013 Valencia, Spain
| | - M Ulrich
- Institutionen för fysik kemi och biologi (IFM), Linköping Universitet, Olaus Magnus väg, 583 30 Linköping, Sweden
| | - P Hopkins
- Swansea Lab for Animal Movement, Biosciences, College of Science, Swansea University, Swansea SA2 8PP, UK
| | - C Duarte
- Red Sea Research Centre, King Abdullah University of Science and Technology (KAUST), Thuwal 23955, Saudi Arabia
| | - C Eizaguirre
- School of Biological and Chemical Sciences, Queen Mary University of London, London E35SA, UK
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Loeb HS, Bredakis J, Gunner RM. Superiority of dobutamine over dopamine for augmentation of cardiac output in patients with chronic low output cardiac failure. Circulation 1977; 55:375-8. [PMID: 318933 DOI: 10.1161/01.cir.55.2.375] [Citation(s) in RCA: 175] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Dobutamine is a newly developed catecholamine reported to have minimal direct vascular effects relative to its inotropic activity and to have less chronotropic and arrhythmogenic properties than other catecholamines used in the treatment of low output states. In this study, the acute hemodynamic effects of dobutamine were compared to those of dopamine in 13 patients with chronic low output cardiac failure. At dosages adjusted to achieve similar increments in cardiac output, dobutamine reduced left ventricular filling pressure (LVEP) from 24 +/- 2 mm Hg (SEM) to 17+/- 2 mm Hg, while dopamine increased LVEP to 30 +/- 3 mm Hg and in six patients caused arterial O2 saturation to fall below 90%. This poor response to dopamine was probably the result of its vasoconstrictive effects and illustrates the potential advantages of using a cardioselective agent such as dobutamine when the desired goal of therapy is to improve ventricular function by direct inotropic stimulation.
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