scholarly journals Differential influence of Slc7a11 expression and body condition on pheomelanin‐based pigmentation in two Eurasian nuthatch Sitta europaea populations with different predation risk

2020 ◽  
Vol 51 (5) ◽  
Author(s):  
Ismael Galván ◽  
Juan José Sanz
Keyword(s):  
Predation Risk ◽  
Body Condition ◽  
Sitta Europaea

scholarly journals Glucocorticoids, state-dependent reproductive investment and success in the face of danger in a long-lived bird

2020 ◽  
Author(s):  
Kristina Noreikienė ◽  
Kim Jaatinen ◽  
Benjamin B. Steele ◽  
Markus Öst
Keyword(s):  
Predation Risk ◽  
Telomere Length ◽  
Clutch Size ◽  
Body Condition ◽  
Nest Predation ◽  
Hatching Success ◽  
Reproductive Investment ◽  
Trade Off ◽  
Relative Telomere Length ◽  
Future Reproduction

AbstractGlucocorticoid hormones may mediate trade-offs between current and future reproduction. However, understanding their role is complicated by predation risk, which simultaneously affects the value of the current reproductive investment and elevates glucocorticoid levels. Here, we shed light on these issues in long-lived female Eiders (Somateria mollissima) by investigating how current reproductive investment (clutch size) and hatching success relate to faecal glucocorticoid metabolite [fGCM] level and residual reproductive value (minimum years of breeding experience, body condition, relative telomere length) under spatially variable predation risk. Our results showed a positive relationship between colony-specific predation risk and mean colony-specific fGCM levels. Clutch size and female fGCM were negatively correlated only under high nest predation and in females in good body condition, previously shown to have a longer life expectancy. We also found that younger females with longer telomeres had smaller clutches. The drop in hatching success with increasing fGCM levels was least pronounced under high nest predation risk, suggesting that elevated fGCM levels may allow females to ensure some reproductive success under such conditions. Hatching success was positively associated with female body condition, with relative telomere length, particularly in younger females, and with female minimum age, particularly under low predation risk, showing the utility of these metrics as indicators of individual quality. In line with a trade-off between current and future reproduction, our results show that high potential for future breeding prospects and increased predation risk shift the balance toward investment in future reproduction, with glucocorticoids playing a role in the resolution of this trade-off.

Food supplementation and predation risk in harsh climate: interactive effects on abundance and body condition of tit species

Oikos ◽  
2016 ◽  
Vol 126 (6) ◽  
pp. 863-873 ◽  
Author(s):  
Chiara Morosinotto ◽  
Alexandre Villers ◽  
Rauno Varjonen ◽  
Erkki Korpimäki
Keyword(s):  
Predation Risk ◽  
Body Condition ◽  
Interactive Effects ◽  
Food Supplementation ◽  
Harsh Climate

Does body condition affect fecundity in a cyclic population of snowshoe hares?

1999 ◽  
Vol 77 (1) ◽  
pp. 1-6 ◽  
Author(s):  
Karen E Hodges ◽  
Carol I Stefan ◽  
Elizabeth A Gillis
Keyword(s):  
Predation Risk ◽  
Body Condition ◽  
Age Structure ◽  
Lepus Americanus ◽  
Decline Phase ◽  
Skeletal Size ◽  
Nutritional Deficit ◽  
Snowshoe Hares ◽  
Cyclic Changes ◽  
Cyclic Fluctuation

Snowshoe hares (Lepus americanus) undergo a 10-year cycle in abundance, with cyclic changes in reproduction occurring 3 years prior to numeric changes. Reproduction may be associated with body condition, which might change with nutrition or predation pressure. We describe hare body condition (as a mass - skeletal size relationship) through a cycle in the southern Yukon from 1989 to 1996, test the effects of food and predation risk on body condition, and examine whether changes in body condition are related to cyclic reproductive changes. Hare body condition was lowest during the decline phase but rapidly improved during the low phase. Although yearling hares were in poorer condition than adults, changes in age structure cannot explain the cyclic fluctuation in condition. Food addition and predator reduction both resulted in better body condition. Body condition did not affect reproduction. The highest natality occurred when hares were in intermediate condition, while the lowest natality occurred when hares were in the best condition. Although changes in food and predation risk affect hare body condition, we found no relationship between body condition and cyclic reproductive changes. Rather, during times of nutritional deficit, female hares may maintain mass during gestation and lactation, but at a proximate cost to their offspring. Thus, inferences based on indices of condition incorporating body mass may be misleading.

scholarly journals Body condition and pregnancy in northern Yellowstone elk: Evidence for predation risk effects?

2011 ◽  
Vol 21 (1) ◽  
pp. 3-8 ◽  
Author(s):  
P. J. White ◽  
Robert A. Garrott ◽  
Kenneth L. Hamlin ◽  
Rachel C. Cook ◽  
John G. Cook ◽  
...  
Keyword(s):  
Predation Risk ◽  
Body Condition ◽  
Risk Effects

Habitat deterioration affects antipredatory behavior, body condition, and parasite load of female Psammodromus algirus lizards

2007 ◽  
Vol 85 (6) ◽  
pp. 743-751 ◽  
Author(s):  
Luisa Amo ◽  
Pilar López ◽  
José Martín
Keyword(s):  
Predation Risk ◽  
Body Condition ◽  
Relative Abundance ◽  
Microhabitat Use ◽  
Health State ◽  
Habitat Deterioration ◽  
Antipredatory Behavior ◽  
Risk Of Predation ◽  
Psammodromus Algirus

Deforestation may increase predation risk for prey because it may make prey more conspicuous and limit the number of refuges suitable to avoid predators. Therefore, prey may need to increase the magnitude of escape responses. However, excessive antipredatory effort might lead to a loss of body mass and a decrease in defense against parasites, with important consequences for short- and long-term fitness. We analyzed whether Psammodromus algirus (L., 1758) lizards that inhabit patches with different levels of deterioration of the vegetation within the same oak forest differed in relative abundance numbers, microhabitat use, antipredatory strategies, and health state. Results showed lizards selected similar microhabitats regardless of the level of deterioration of the vegetation and relative abundance of lizards was similar in both areas. However, habitat deterioration seemed to increase predation risk, at least for females, because they were detected at longer distances in deteriorated areas. Females seemed to adjust their antipredatory behavior accordingly to high risk of predation by increasing approach distances allowed to predators. The costs associated with frequent antipredatory displays might explain why females in deteriorated habitats had lower body condition and greater blood parasite loads than females in natural areas. This loss of body condition and increased parasitemia might have deleterious consequences for female fitness and therefore affect the maintenance of lizard populations in the long-term.

scholarly journals Effect of predation risk and ectoparasitic louse flies on physiological stress condition of the red-tailed tropicbird (Phaethon rubricauda) from Rapa Nui and Salas & Gómez islands

PeerJ ◽  
2020 ◽  
Vol 8 ◽  
pp. e9088
Author(s):  
Nicolas Luna ◽  
Andrea I. Varela ◽  
Guillermo Luna-Jorquera ◽  
Katherina Brokordt
Keyword(s):  
Predation Risk ◽  
Body Condition ◽  
Physiological Stress ◽  
The Body ◽  
Rapa Nui ◽  
Stress Indicators ◽  
Stress Indicator ◽  
Introduced Predators ◽  
Significant Difference ◽  
Phaethon Rubricauda

Background Introduced predators at seabird colonies and parasites may have lethal and/or sub-lethal consequences for bird populations. We assessed the potential sub-lethal negative effects of these stressors in a native seabird listed as vulnerable in its south-eastern pacific distribution. This study was conducted in two red-tailed tropicbird (Phaethon rubricauda) colonies, one located in Rapa Nui Island, which is threatened by the presence of introduced predators, and the other located in Salas & Gómez Island, which has no introduced predators, but birds are infested by ectoparasitic louse flies. Methods The effects on physiological stress traits of both, predation risk on different nest types (protected and exposed) on Rapa Nui, and different levels of louse flies’ parasitic loads on Salas & Gómez were studied. Three variables were analyzed: the heterophil/lymphocyte (H/L) ratio, the transcriptional levels of mRNA HSP70 in blood, and the body condition. These stress indicators and leukocyte counts were compared between colonies. Results No significant differences were found in any stress indicator between different nest types within Rapa Nui, showing that the effect of predator’s presence was the same for adults nesting in both, protected and exposed nests. No significant correlation was found between louse flies’ parasitic loads and any stress indicators in the birds of Salas & Gómez. Also, there was no difference in any stress indicator between islands. However, a significant opposite trend between islands was found in the eosinophil, lymphocyte, and monocyte counts when related to body condition. Conclusions We found a lack of significant differentiation in all the stress level indicators assessed within and between islands. The presence of louse flies in Salas & Gómez vs. the absence of this parasite at Rapa Nui may be the cause for the significant difference in the trend of eosinophil, lymphocyte and monocyte counts between the islands. However, further studies are necessary to elucidate the reason for this difference and to better investigate the lethal effects of introduced predators on the Rapa Nui colony to evaluate appropriate conservation measures for this native seabird.

scholarly journals Maternal body condition influences magnitude of anti-predator response in offspring

2014 ◽  
Vol 281 (1794) ◽  
pp. 20141806 ◽  
Author(s):  
Amanda M. Bennett ◽  
Dennis L. Murray
Keyword(s):  
Predation Risk ◽  
Body Condition ◽  
Effect Size ◽  
Maternal Influence ◽  
Maternal Condition ◽  
Morphological Effect ◽  
Leopard Frogs ◽  
Maternal Provisioning ◽  
Northern Leopard Frogs ◽  
The Relationship

Organisms exhibit plasticity in response to their environment, but there is large variation even within populations in the expression and magnitude of response. Maternal influence alters offspring survival through size advantages in growth and development. However, the relationship between maternal influence and variation in plasticity in response to predation risk is unknown. We hypothesized that variation in the magnitude of plastic responses between families is at least partly due to maternal provisioning and examined the relationship between maternal condition, egg provisioning and magnitude of plastic response to perceived predation risk (by dragonfly larvae: Aeshna spp.) in northern leopard frogs ( Lithobates pipiens ). Females in better body condition tended to lay more (clutch size) larger (egg diameter) eggs. Tadpoles responded to predation risk by increasing relative tail depth (morphology) and decreasing activity (behaviour). We found a positive relationship between morphological effect size and maternal condition, but no relationship between behavioural effect size and maternal condition. These novel findings suggest that limitations imposed by maternal condition can constrain phenotypic variation, ultimately influencing the capacity of populations to respond to environmental change.

The influence of predation risk on foraging behaviour of brushtail possums in Australian woodlands

2005 ◽  
Vol 32 (2) ◽  
pp. 121 ◽  
Author(s):  
Karolyne N. Pickett ◽  
David S. Hik ◽  
Alan E. Newsome ◽  
Roger P. Pech
Keyword(s):  
Reproductive Success ◽  
Predation Risk ◽  
Body Condition ◽  
Foraging Behaviour ◽  
Red Fox ◽  
Conservation Strategies ◽  
Habitat Types ◽  
Lethal Effects ◽  
Giving Up Density ◽  
Cypress Pine

The potential effects of predation risk on common brushtail possums were investigated in south-eastern Australian woodlands. Patterns of habitat use, foraging costs using giving-up density (GUD) experiments, and indices of body condition and reproductive success were examined at eight sites in two habitat types (eucalypt- or cypress-pine–dominated stands), within three areas of different red fox abundance (high, moderate and low fox density). In cypress-pine–dominated stands, possums travelled further on the ground, visited more feeding stations and had lower GUDs at feeders where foxes were removed than did possums in high-fox-density sites. In contrast, there was no effect of fox removal on the behaviour of possums in eucalypt-dominated stands. Fox removal also had no effect on indices of body condition and reproduction. Minor effects of microhabitat were detected with trackplot and GUD experiments, but, overall, the results suggest that habitat at the stand-level was more important. The non-lethal effects of foxes in different habitats may need to be taken into account when developing conservation strategies for native marsupials.

scholarly journals Parental Investment Under Predation Threat in Incubating Common Eiders (Somateria mollissima): A Hormonal Perspective

2021 ◽  
Vol 9 ◽  
Author(s):  
Bertille Mohring ◽  
Frédéric Angelier ◽  
Kim Jaatinen ◽  
Charline Parenteau ◽  
Markus Öst
Keyword(s):  
Predation Risk ◽  
Body Condition ◽  
Parental Investment ◽  
Nest Predation ◽  
Hatching Success ◽  
Reproductive Investment ◽  
Somateria Mollissima ◽  
Common Eiders ◽  
Adaptation Hypothesis ◽  
The Impact

Predation risk affects the costs and benefits of prey life-history decisions. Predation threat is often higher during reproduction, especially in conspicuous colonial breeders. Therefore, predation risk may increase the survival cost of breeding, and reduce parental investment. The impact of predation risk on avian parental investment decisions may be hormonally mediated by prolactin and corticosterone, making them ideal tools for studying the trade-offs involved. Prolactin is thought to promote parental care and commitment in birds. Corticosterone is involved in allostasis and may either mediate reduced parental investment (corticosterone-fitness hypothesis), or promote parental investment through a reallocation of resources (corticosterone-adaptation hypothesis). Here, we used these hormonal proxies of incubation commitment to examine the impact of predation risk on reproduction in common eiders (Somateria mollissima) breeding in the Baltic Sea. This eider population is subject to high but spatially and temporally variable predation pressure on adults (mainly by the white-tailed eagle Haliaeetus albicilla and introduced mammalian predators) and nests (by the adult predators and exclusive egg predators such as hooded crows Corvus cornix). We investigated baseline hormonal levels and hatching success as a function of individual quality attributes (breeding experience, female and duckling body condition), reproductive investment (clutch weight), and predation risk. We expected individuals nesting in riskier environments (i.e., on islands where predation on adults or nests is higher, or in less concealed nests) to reduce their parental investment in incubation, reflected in lower baseline prolactin levels and either higher (corticosterone-fitness hypothesis) or lower (corticosterone-adaptation hypothesis) baseline corticosterone levels. Contrary to our predictions, prolactin levels showed a positive correlation with nest predation risk. The unexpected positive relationship could result from the selective disappearance of low-quality females (presumably having low prolactin levels) from risky sites. Supporting this notion, female body condition and hatching success were positively correlated with predation risk on females, and baseline prolactin concentrations were positively correlated with duckling body condition, a proxy of maternal quality. In line with the corticosterone-adaptation hypothesis, baseline corticosterone levels increased with reproductive investment, and were negatively associated with nest predation risk. Hatching success was lower on islands where nest predation risk was higher, consistent with the idea of reduced reproductive investment under increased threat. Long-term individual-based studies are now needed to distinguish selection processes occurring at the population scale from individually plastic parental investment in relation to individual quality and variable predation risk.

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