Size matters: Management of stress responses and chronic stress in beaked whales and other marine mammals may require larger exclusion zones

2011 ◽  
Vol 63 (1-4) ◽  
pp. 5-9 ◽  
Author(s):  
Andrew J. Wright ◽  
Terrence Deak ◽  
E.C.M. Parsons
2021 ◽  
Vol 14 (1) ◽  
Author(s):  
Joëlle De Weerdt ◽  
Eric Angel Ramos ◽  
Etienne Pouplard ◽  
Marc Kochzius ◽  
Phillip Clapham

AbstractDocumenting marine mammal strandings provides important information needed to understand the occurrence and distribution patterns of species. Here, we report on strandings of cetaceans on the Pacific (n = 11) and Caribbean (n = 2) coasts of Nicaragua, documented opportunistically from 2014 to 2021. Strandings included three species of baleen whale (blue whale Balaenoptera musculus, Bryde’s whale Balaenoptera edeni, humpback whale Megaptera novaeangliae) and five species of toothed whale (dwarf sperm whale Kogia sima, Guiana dolphin Sotalia guianensis, pantropical spotted dolphin Stenella attenuata, spinner dolphin Stenella longirostris, Cuvier’s beaked whale Ziphius cavirostris). These are the first published accounts of blue whales, Bryde’s whales, dwarf sperm whales, and Cuvier’s beaked whales in Nicaraguan waters. Limited resources and the advanced decomposition of animals prevented necropsies in most cases, the identification of the causes of mortality in all cases, and the species identification of two dolphins. Information derived from these stranding events offers new insights into the occurrence of marine mammals on the Pacific and Caribbean coasts of Nicaragua and Central America.


2003 ◽  
Vol 285 (5) ◽  
pp. E1110-E1117 ◽  
Author(s):  
D. Zelena ◽  
Z. Mergl ◽  
A. Földes ◽  
K. J. Kovács ◽  
Z. Tóth ◽  
...  

The role of hypothalamic structures in the regulation of chronic stress responses was studied by lesioning the mediobasal hypothalamus or the paraventricular nucleus of hypothalamus (PVH). Rats were acutely (60 min) and/or repeatedly (for 7 days) restrained. In controls, a single restraint elevated the plasma adrenocorticotropin (ACTH), corticosterone, and prolactin levels. Repeated restraint produced all signs of chronic stress, including decreased body and thymus weights, increased adrenal weight, basal corticosterone levels, and proopiomelanocortin (POMC) mRNA expression in the anterior pituitary. Some adaptation to repeated restraint of the ACTH response, but not of other hormonal responses, was seen. Lesioning of the mediobasal hypothalamus abolished the hormonal response and POMC mRNA activation to acute and/or repeated restraint, suggesting that the hypothalamo-pituitary-adrenal axis activation during repeated restraint is centrally driven. PVH lesion inhibited the ACTH and corticosterone rise to the first restraint by ∼50%. In repeatedly restrained rats with PVH lesion, the ACTH response to the last restraint was reduced almost to basal control levels, and the elevation of POMC mRNA level was prevented. PVH seems to be important for the repeated restraint-induced ACTH and POMC mRNA stimulation, but it appears to partially mediate other restraint-induced hormonal changes.


2017 ◽  
Vol 57 (3) ◽  
pp. 401 ◽  
Author(s):  
C. Burnard ◽  
C. Ralph ◽  
P. Hynd ◽  
J. Hocking Edwards ◽  
A. Tilbrook

There is considerable interest in the potential for measuring cortisol in hair as a means of quantifying stress responses in human and non-human animals. This review updates the rapid advancement in our knowledge of hair cortisol, methods for its measurement, its relationship to acute and chronic stress, and its repeatability and heritability. The advantages of measuring cortisol in hair compared with other matrices such as blood, saliva and excreta and the current theories of the mechanisms of cortisol incorporation into the fibre are described. Hair cortisol as a measure of the physiological response to stress in a variety of species is presented, including correlations with other sample matrices, the relationship between hair cortisol and psychosocial stress and the repeatability and heritability of hair cortisol concentrations. Current standards for the quantification of hair cortisol are critically reviewed in detail for the first time and gaps in technical validation of these methods highlighted. The known effects of a variety of sources of hair cortisol variation are also reviewed, including hair sampling site, sex, age and adiposity. There is currently insufficient evidence to conclude that cortisol concentration in hair accurately reflects long-term blood cortisol concentrations. Similarly, there is a lack of information surrounding the mechanisms of cortisol incorporation into the hair. This review highlights several directions for future research to more fully validate the use of hair cortisol as an indicator of chronic stress.


2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Jérémy Cros ◽  
Lucie Bidlingmeyer ◽  
Robin Rosset ◽  
Kevin Seyssel ◽  
Camille Crézé ◽  
...  

Abstract Background The mechanisms by which chronic stress increases the risk of non-communicable diseases remain poorly understood. On one hand, chronic stress may increase systemic vascular resistance (SVR) and blood pressure, which may lead to blood vessels injury and altered myocardial perfusion. On the other hand, chronic stress may promote the overconsumption of sugar-containing foods and favor obesity. There is indeed evidence that sweet foods are preferentially consumed to alleviate stress responses. The effects of nutritive and non-nutritive sweeteners (NNS) on hemodynamic stress responses remain however largely unknown. Objective/design This study aimed at comparing the effects of sucrose-containing and NNS-containing drinks, as compared to unsweetened water, on hemodynamic responses to acute stress in twelve healthy female subjects. Acute stress responses were elicited by a 30-min mental stress (5-min Stroop’s test alternated with 5-min mental arithmetic) and a 3-min cold pressure test (CPT), each preceded by a resting baseline period. Hemodynamic stress responses were investigated by the repeated measurement of mean arterial pressure and the continuous monitoring of cardiac output by thoracic electrical bioimpedance measurement. SVR was selected as a primary outcome because it is a sensitive measure of hemodynamic responses to acute stress procedures. Results With all three drinks, SVR were not changed with mental stress (P = 0.437), but were increased with CPT (P = 0.045). Both mental stress and CPT increased mean arterial pressure and heart rate (all P < 0.001). Cardiac output increased with mental stress (P < 0.001) and remained unchanged with CPT (P = 0.252). No significant differences in hemodynamic responses were observed between water, sucrose and NNS (stress × condition, all P > 0.05). Conclusions These results demonstrate that sucrose and NNS do not alter hemodynamic responses to two different standardized acute stress protocols.


2012 ◽  
Vol 1469 ◽  
pp. 54-62 ◽  
Author(s):  
Reji Babygirija ◽  
Sazu Yoshimoto ◽  
Irena Gribovskaja-Rupp ◽  
Mehmet Bülbül ◽  
Kirk Ludwig ◽  
...  

2005 ◽  
Vol 35 (3) ◽  
pp. 541-556 ◽  
Author(s):  
Eric Mellina ◽  
Scott G Hinch ◽  
Edward M Donaldson ◽  
Greg Pearson

The impacts associated with streamside clear-cut logging (e.g., increased temperatures and sedimentation, loss of habitat complexity) are potentially stressful to stream-dwelling fish. We examined stream habitat and rainbow trout physiological stress responses to clear-cut logging in north-central British Columbia using 15 streams divided into three categories: old growth (reference), recently logged (clear-cut to both banks 1–9 years prior to the study), and second growth (clear-cut 25–28 years prior to the study). We used plasma cortisol and chloride concentrations as indicators of acute stress, and interrenal nuclear diameters, impairment of the plasma cortisol response, and trout condition and length-at-age estimates as indicators of chronic stress. No statistically significant acute or chronic stress responses to streamside logging were found, despite increases in summertime stream temperatures (daily maxima and diurnal fluctuations) and a reduction in the average overall availability of pool habitat. Our observed stress responses were approximately an order of magnitude lower than what has previously been reported in the literature for a variety of different stressors, and trout interrenal nuclear diameters responses to the onset of winter were approximately five times greater than those to logging. The overall consistency of our results suggests that the impacts of streamside clear-cut logging are not acutely or chronically stressful to rainbow trout in our study area.


2020 ◽  
Vol 17 (36) ◽  
pp. 346-356
Author(s):  
Daria I BEREZINA ◽  
Lyubov L FOMINA

Carp (Cyprinidae) is one of the dominating and most valuable fish species in fish farming. Under conditions of high-intensity cultivation, fish are systematically exposed to extreme factors that cause stress reactions, accompanied by changes in the functional state of the defense of the body systems and exert impact, primarily, on hematological parameters. The hemostatic system is one such defense systems, which counteracts bleeding through a coagulation mechanism. Hemocoagulation follows the same pattern in all vertebrates, from jawless fish to mammals, and represents an ancient adaptation of animals to stressful conditions, often associated with blood loss in nature. This research aimed to study the effect of hormone-induced stress on plasma (secondary) hemostasis in fish. Given the data fragmentation and differences in methodology and conditions, the lack of standardization in studying hemostasis in fish, especially in critical conditions, this problem remains not fully disclosed in global science. The article presents the results of studying carp (Cyprinus carpio) coagulogram parameters under the influence of acute and chronic stress responses, simulated by injections of synthetic cortisol analogs (dexamethasone for short-term stress, and betamethasone for chronic stress) during 21 days. The dynamics of these indicators were analyzed in comparison to intact fish. It has been established that by accelerating the activated partial thromboplastin time, prothrombin time, and increasing the amount of fibrinogen in the blood of fish, blood coagulation processes were clearly accelerated in all groups of animals tested by the last day of the experiment. The dynamics of other parameters, such as the content of soluble fibrin monomer complexes or antithrombin III content, indicated the simultaneous development of hypercoagulation processes in some groups. Assumptions have been made to explain the pattern of changes observed not only in treated fish but also in control animals.


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