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Abstract

Measuring hormone metabolites from excreta is a powerful method to study hormone-behavior relationships. Currently, fecal corticosterone metabolite concentrations are used to estimate individual short-term stress responses. From the free-roaming, semitame flock of greylag geese (Anser anser), as many fecal samples as possible were collected over 3 h following a challenge (social density stress) or in a control situation. This time span corresponds to the gut passage time of geese. It was asked how many samples were necessary to determine differences in excreted corticosterone immunoreactive metabolites (CORTs) between control and social density stress and which parameters (means, maxima, range) reliably showed this difference. A large variation of CORT was found between consecutive samples. Still, means, maxima, and ranges of the samples in a fecal series consistently showed the response to a stressor both within and between individuals. Three samples sufficed if the maximum value of CORT was used, whereas four or more samples were necessary to work with the mean. It was concluded that by increasing the number of fecal samples collected, the course of CORT could be measured more precisely and an individual's acute stress response inferred more reliably.

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... One of us (I.S.) observed all agonistic interactions of the members of one focal family during morning feedings on two consecutive days, a control day, when food was distributed widely (~150 m 2 ), and a social density stress situation, in which the same amount of food was spread over approximately a quarter of that area (~40 m 2 ). Social density stress feeding has been shown to introduce a competitive feeding situation (Kotrschal et al., 1993) resulting in an increased excretion of immuno-reactive corticosterone metabolites (Scheiber et al., 2005b;D. Frigerio, unpubl.) ...
... Our endocrine data thus include the corticosterone situation during and short after the morning feedings. As geese defecate approximately every 20 min (Kotrschal et al., 2000;Scheiber et al., 2005b) and variation between individual samples tends to be high in geese, we attempted to collect short series of three fecal samples per individual on control days, and four samples on social density stress days, to counteract variability in excreted CORT over time to provide more reliable results (Scheiber et al., 2005b). This, however, was not always possible. ...
... Our endocrine data thus include the corticosterone situation during and short after the morning feedings. As geese defecate approximately every 20 min (Kotrschal et al., 2000;Scheiber et al., 2005b) and variation between individual samples tends to be high in geese, we attempted to collect short series of three fecal samples per individual on control days, and four samples on social density stress days, to counteract variability in excreted CORT over time to provide more reliable results (Scheiber et al., 2005b). This, however, was not always possible. ...
Article
Social interactions are among the most potent stressors. However, social allies may diminish stress, increase success in agonistic encounters and ease access to resources. We studied the role of social support as a major mechanism for individual stress management in families of free-ranging greylag geese (Anser anser). Greylag geese are long-term monogamous, live in a female-bonded social system, and fledged offspring stay with their parents until the next breeding season ('primary families'). Should parents then fail to fledge young, subadults might rejoin them in summer after molt is completed ('secondary families'). We have previously shown that primary greylag goose families reap benefits from active social support in agonistic encounters, and also excrete lower levels of immuno-reactive corticosterone metabolites (CORT, 'passive social support'). Here we investigated how far active and passive social support continues in secondary goose families. Although we found that active support in agonistic encounters was almost absent in secondary families, subadult male geese won an increased number of agonistic encounters due to the mere presence of their secondary family. Particularly adult and subadult females benefited from passive social support through decreased CORT, whereas males did not. Decrease in the hormonal stress response during challenging situations, induced by social allies, may help the females' long-term energy management, thereby improving the odds for successful future reproduction. We discuss whether joining a secondary family may be an alternative tactic for young geese towards optimizing their start into a complex social life.
... Every few years a few geese are carefully handraised to keep the flock accessible to humans. Both hand-raised and gooseraised flock members are habituated to the close presence of humans [91] and do not show avoidance behavior, elevated levels of immuno-reactive corticosterone metabolites [92] or significant heart rate changes when familiar humans approach [93]. Many studies pertaining to the social life of geese, in an attempt to decipher even subtle costs and benefits to sociality, have been performed with this flock, and we summarized those findings in a book recently [77]. ...
... families, x, xii, 30, 112, 113, 115, 116, 131, 139, 140, 141, 150, 154, 155, 156, 157, 159, 162, 163, 164 farmers, ix, 44, 45, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 64, 65, 69, 86 farms, vii, ix, 28, 44, 45, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 58, 59, 62, 68, 70 fecundity, vi, viii, xii, 189, 190, 200 female natal philopatry, 113 female relatedness, 113 female-biased philopatry, xi, 112,114,130,112,114,128 fertility,47,49,53,54,56,59,62,64,67,70 fertility rate,49,53,56 fidelity,139,207,216 flock dynamics,112 food,vii,x,8,14,16,17,21,23,24,26,30,74,84,114,130,146,175,190,197,199,200,201,224 food intake,146 forest ecosystem,86 forest formations,150,152,158,160,164 forest fragments,xi,150,164 France,18,33,45,46,48,63,166,191 fruits,viii,xii,190,192,201 G gazelle, 89 genotype,25,26,27,28,29,36,37,58,59,178,185,213 genus,viii,xiii,5,31,86,161,174,175,190,205,206,220,223 Germany,35,46,111,192 Giardia,viii,xiii,184,185,220,221,222,223,224,225,226 Giardia psittaci,220,224 giardiasis,vi,219,223,224,225 Giraffe,89,102 glucocorticoids,131,146 goose,vii,xi,112,115,116,117,118,120,128,136,138,139,140,141,144,146 granulomas,viii,2,20,21 grazing,59,70,80 greater white-fronted goose (Anser albifrons frontalis), 115 Greenland white-fronted goose (A. a. flavirostris), 115 greylag goose,vii,xi,112,117,140,141 Guinea,74,75,76,77,80,82,86,75,77 H habitat,xi,76,77,80,81,82,83,84,86,98,103,143,150,151,164,169 habitat occupation,xi,150,164 health,ix,41,44,46,47,48,50,51,54,56,57,59,64,66,67,70,91,92,176,177 health problems,50,51,177 heterogeneity,33,64,164 history,viii,x,xiii,73,98,99,103,106,118,119,135,137,141,190,199,206 hormones,70,131,146 human,vii,x,xii,5,73,80,82,83,84,86,87,92,93,94,96,97,101,102,106, ...
... families, x, xii, 30, 112, 113, 115, 116, 131, 139, 140, 141, 150, 154, 155, 156, 157, 159, 162, 163, 164 farmers, ix, 44, 45, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 64, 65, 69, 86 farms, vii, ix, 28, 44, 45, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 58, 59, 62, 68, 70 fecundity, vi, viii, xii, 189, 190, 200 female natal philopatry, 113 female relatedness, 113 female-biased philopatry, xi, 112,114,130,112,114,128 fertility,47,49,53,54,56,59,62,64,67,70 fertility rate,49,53,56 fidelity,139,207,216 flock dynamics,112 food,vii,x,8,14,16,17,21,23,24,26,30,74,84,114,130,146,175,190,197,199,200,201,224 food intake,146 forest ecosystem,86 forest formations,150,152,158,160,164 forest fragments,xi,150,164 France,18,33,45,46,48,63,166,191 fruits,viii,xii,190,192,201 G gazelle, 89 genotype,25,26,27,28,29,36,37,58,59,178,185,213 genus,viii,xiii,5,31,86,161,174,175,190,205,206,220,223 Germany,35,46,111,192 Giardia,viii,xiii,184,185,220,221,222,223,224,225,226 Giardia psittaci,220,224 giardiasis,vi,219,223,224,225 Giraffe,89,102 glucocorticoids,131,146 goose,vii,xi,112,115,116,117,118,120,128,136,138,139,140,141,144,146 granulomas,viii,2,20,21 grazing,59,70,80 greater white-fronted goose (Anser albifrons frontalis), 115 Greenland white-fronted goose (A. a. flavirostris), 115 greylag goose,vii,xi,112,117,140,141 Guinea,74,75,76,77,80,82,86,75,77 H habitat,xi,76,77,80,81,82,83,84,86,98,103,143,150,151,164,169 habitat occupation,xi,150,164 health,ix,41,44,46,47,48,50,51,54,56,57,59,64,66,67,70,91,92,176,177 health problems,50,51,177 heterogeneity,33,64,164 history,viii,x,xiii,73,98,99,103,106,118,119,135,137,141,190,199,206 hormones,70,131,146 human,vii,x,xii,5,73,80,82,83,84,86,87,92,93,94,96,97,101,102,106, ...
Chapter
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The conservation of the lion (Panthera leo), a dominant apex predator, indispensable ecological mainstay and popular wildlife symbol, is one of the most important issues in current conservation biology research and indeed is a relevant topic for other disciplines such as applied ecology, biogeography and political ecology. The conservation issues for the West African lion subspecies or variant (Panthera leo senegalensis or Panthera leo leo) are particularly important, because the ecology and status of this subspecies are less researched than those of the Southern, Eastern, Asiatic and even extinct North African lions. The West African lion is considered endangered and its changing populations, history, human relations and current prospects are little known beyond presence data. This chapter conducts a status assessment, based on a comprehensive literature review, of the conservation issues of the West African lion. A key issue is the lack of analysis of the human dimensions of lion presence in the increasingly human dominated landcover of West Africa, and lack of applications of relevant knowledge from studies of lions and other large carnivores in other contexts and the multidisciplinary theoretical analyses that could be applied to this issue. It is concluded that without an intensive effort to rectify the factors for the rarity or extirpation of the West African lion (extremely high human population growth and urbanization, desertification, decline of food sources, cattle herding, hunting and farming) and increased public acknowledgement of this comparatively neglected lion subspecies, the West African lion has a bleak future. A common, cross-border conservation policy among the West African nations will be required, not only for lions but for prey species and human landusers.
... This prompted the 170 individuals to feed tightly together. Condition (ii) represents a standard feeding situation, whereas condition (iv) was shown to be a competitive feeding situation (Kotrschal et al., 1993; Weiβ and Kotrschal, 2004), which modulates excretion of immuno-reactive corticosterone metabolites (Scheiber et al., 2005b). In both situations, behavioral observations started at the beginning of the morning feeding, i.e. from 0750 to 0820 h, and lasted until the focal goose left the feeding area. ...
... In geese, fecal samples represent an integrated, proportional record of the plasma glucocorticosterone and testosterone levels 30–180 min prior to defecation (Kotrschal et al., 1998; Kotrschal et al., 2000; Scheiber et al., 2005b). We collected fecal samples after (i) handling trials and following the social situations (ii) and (iv). ...
... Modulation of hormonal excretion in response to the challenging conditions (i) and (iv) was estimated as the difference between the slope of the regression line during challenge (k1) and that of the regression line in the appropriate matched control (k2) by dividing (k1) by (k2). We determined an individual's hormonal excretion using the " cumulative method " rather than calculating a mean as proposed by Scheiber et al. (2005b), because during challenges defecation is accelerated. As a result, a larger number of droppings per unit time are deposited, which may lead to an underestimate of hormonal levels. ...
Article
The concept of personality implies individual differences in behavior and physiology that show some degree of repeatability/consistency over time and across contexts. Most studies of animal personality, particularly studies of individuals' variation in physiological mechanisms, have been conducted on selected individuals in controlled conditions. We attempted to detect consistent behaviors as well as physiological patterns in greylag ganders (Anser anser) from a free-roaming flock living in semi-natural conditions. We tested 10 individuals repeatedly, in a handling trial, resembling tests for characterization of “temperaments” in captive animals. We recorded the behavior of the same 10 individuals during four situations in the socially intact flock: (1) a “low density feeding condition”, (2) a “high density feeding condition”, (3) a “low density post-feeding situation” and (4) while the geese rested. We collected fecal samples for determination of excreted immuno-reactive corticosterone (BM) and testosterone metabolites (TM) after handling trials, as well as the “low density feeding” and the “high density feeding” conditions. BM levels were very highly consistent over the repeats of handling trials, and the “low density feeding condition” and tended to be consistent over the first two repeats of the “high density feeding condition”. Also, BM responses tended to be consistent across contexts. Despite seasonal variation, there tended to be inter-test consistency of TM, which pointed to some individual differences in TM as well. Aggressiveness turned out to be a highly repeatable trait, which was consistent across social situations, and tended to correlate with an individual's resistance during handling trials. Also, “proximity to the female partner” and “sociability” – the average number of neighboring geese in a close distance while resting – were consistent. We conclude that aggressiveness, “affiliative tendencies” and levels of excreted corticosterone and testosterone metabolites may be crucial factors of personality in geese.
... Frigerio, unpubl. data; Scheiber et al., 2005), nor do they significantly change heart rates when familiar humans approach (Wascher, 2005). This indicates that human observers do not cause stress and, for example, probably will not negatively affect agonistic motivation even in the goose-raised geese.Table 1). ...
... One of us observed all agonistic interactions of the members of one focal family per day during morning feedings on two continuous days, a control day, when food was distributed widely (∼150 m 2 ), and a social density stress situation, in which the same amount of food was spread over approximately a quarter of that area (∼40 m 2 ). This situation has been shown to introduce a competitive feeding situation (Kotrschal et al., 1993; Scheiber et al., 2005 ; D. Frigerio, unpubl. data) and actually results in an increased excretion of immunoreactive corticosterone metabolites (Scheiber et al., 2005). ...
... This situation has been shown to introduce a competitive feeding situation (Kotrschal et al., 1993; Scheiber et al., 2005 ; D. Frigerio, unpubl. data) and actually results in an increased excretion of immunoreactive corticosterone metabolites (Scheiber et al., 2005). A family was observed for the entire time it spent in the feeding area, or for a maximum of one hour, whichever occurred first. ...
Article
In general, support by social allies may reduce stress, increase success in agonistic encounters and ease access to resources. Social support was mainly known from mammals, particularly primates, and has been studied in birds only recently. Basically two types are known: (i) 'active social support', which describes the participation of a social ally in agonistic encounters, and (ii) 'passive social support' in which the mere presence of a social ally reduces behavioural and physiological stress responses. In greylag geese (Anser anser) offspring stay with their parents for an entire year or even longer and therefore are a candidate avian model to study support by social allies. We investigated the effects of active and passive social support in ten families (ten males, ten females, 33 juveniles) in a free-roaming, semi-tame flock of greylag geese. Focal individuals were observed during three time periods: (i) re-establishment of the flock in the fall, (ii) stable winter flock, and (iii) disintegration of the flock and break-up of family bonds. We recorded all agonistic interactions of the members of one focal family during morning feedings for two consecutive days: a control day, in which food was distributed widely, and a social density stress situation, in which the same amount of food was spread over a much smaller area. In addition, we collected faeces of all individuals within this family for three hours from the beginning of the feeding situation for determining excreted corticosterone immuno-reactive metabolites by enzyme immuno assay. We found that the small families, i.e. pairs with one or two accompanying young, were involved in more agonistic interactions, mainly through the lack of active social support, as compared to large families in the same situation. Members of greylag goose families lost agonistic encounters significantly less often when actively supported. In addition, the excretion of corticosterone metabolites was significantly decreased in large families during a social density stress situation, probably as an effect of passive social support. Via such a socially induced decrease in hormonal stress response during challenging situations, an individual's long term energy management may benefit.
... Our second aim, therefore, was to establish the validity of one available EIA through a capture and restraint challenge performed on a flock of captive barnacle geese. This assay has been applied successfully in a variety of studies in greylag geese (Anser anser) [54][55][56][57]. ...
... Although in birds, renal and faecal matter are jointly excreted via the cloaca [50], the turn-over time of corticosterone in uric acid is faster than from faecal matter, suggesting that the first peak (11:00-11:15) reflects corticosterone metabolites from uric acid, and the second peak (12:30-12:45) might be a sign of corticosterone metabolites from faecal excretion. This is consistent with data found in other goose and sheldgoose species [56,65,66]. ...
... The main goal of this study was to describe the excretion pattern of basal CORTm over a complete polar day in barnacle goslings. As the detection of short steroid metabolite peaks requires frequent sampling [35,56], we opted to collect all samples, rather than at specific times points, a methodology that was suggested as the best option for describing a diel pattern [33]. This is a logistically difficult collection scheme, and so far samples have never been collected in this detailed manner over 24 hours outside the laboratory. ...
Article
Full-text available
Here we describe the excretion pattern of corticosterone metabolites collected from droppings in barnacle goslings (Branta leucopsis) raised under 24 hours of continuous natural light in the Arctic. In lower latitudes, circulating corticosterone peaks around waking and shows a nadir between midnight and 4:00, whereas the peak and nadir are time-delayed slightly when measuring corticosterone metabolites from droppings. Photoperiod, along with other environmental factors, helps to entrain an animal’s endogenous rhythm to that of the natural world. North of the Arctic Circle, photoperiod may not be a reliable cue as light is continuously absent during the winter and continuously present during the summer. Here, for the first time, we used droppings to describe a 24-hour excretion pattern of corticosterone metabolites (CORTm). By applying circular statistics for dependent data, we found a diel rhythmic pattern even under continuous natural light. We discuss potential alternative ‘Zeitgeber’ that may function even in the polar regions, focusing on melatonin. We propose a line of research to measure melatonin non-invasively from droppings. We also provide a validation of the adopted enzyme immunoassay (EIA) that was originally developed for greylag geese.
... Every few years a few geese are carefully handraised to keep the flock accessible to humans. Both hand-raised and gooseraised flock members are habituated to the close presence of humans [91] and do not show avoidance behavior, elevated levels of immuno-reactive corticosterone metabolites [92] or significant heart rate changes when familiar humans approach [93]. Many studies pertaining to the social life of geese, in an attempt to decipher even subtle costs and benefits to sociality, have been performed with this flock, and we summarized those findings in a book recently [77]. ...
... families, x, xii, 30, 112, 113, 115, 116, 131, 139, 140, 141, 150, 154, 155, 156, 157, 159, 162, 163, 164 farmers, ix, 44, 45, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 64, 65, 69, 86 farms, vii, ix, 28, 44, 45, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 58, 59, 62, 68, 70 fecundity, vi, viii, xii, 189, 190, 200 female natal philopatry, 113 female relatedness, 113 female-biased philopatry, xi, 112,114,130,112,114,128 fertility,47,49,53,54,56,59,62,64,67,70 fertility rate,49,53,56 fidelity,139,207,216 flock dynamics,112 food,vii,x,8,14,16,17,21,23,24,26,30,74,84,114,130,146,175,190,197,199,200,201,224 food intake,146 forest ecosystem,86 forest formations,150,152,158,160,164 forest fragments,xi,150,164 France,18,33,45,46,48,63,166,191 fruits,viii,xii,190,192,201 G gazelle, 89 genotype,25,26,27,28,29,36,37,58,59,178,185,213 genus,viii,xiii,5,31,86,161,174,175,190,205,206,220,223 Germany,35,46,111,192 Giardia,viii,xiii,184,185,220,221,222,223,224,225,226 Giardia psittaci,220,224 giardiasis,vi,219,223,224,225 Giraffe,89,102 glucocorticoids,131,146 goose,vii,xi,112,115,116,117,118,120,128,136,138,139,140,141,144,146 granulomas,viii,2,20,21 grazing,59,70,80 greater white-fronted goose (Anser albifrons frontalis), 115 Greenland white-fronted goose (A. a. flavirostris), 115 greylag goose,vii,xi,112,117,140,141 Guinea,74,75,76,77,80,82,86,75,77 H habitat,xi,76,77,80,81,82,83,84,86,98,103,143,150,151,164,169 habitat occupation,xi,150,164 health,ix,41,44,46,47,48,50,51,54,56,57,59,64,66,67,70,91,92,176,177 health problems,50,51,177 heterogeneity,33,64,164 history,viii,x,xiii,73,98,99,103,106,118,119,135,137,141,190,199,206 hormones,70,131,146 human,vii,x,xii,5,73,80,82,83,84,86,87,92,93,94,96,97,101,102,106, ...
... families, x, xii, 30, 112, 113, 115, 116, 131, 139, 140, 141, 150, 154, 155, 156, 157, 159, 162, 163, 164 farmers, ix, 44, 45, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 64, 65, 69, 86 farms, vii, ix, 28, 44, 45, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 58, 59, 62, 68, 70 fecundity, vi, viii, xii, 189, 190, 200 female natal philopatry, 113 female relatedness, 113 female-biased philopatry, xi, 112,114,130,112,114,128 fertility,47,49,53,54,56,59,62,64,67,70 fertility rate,49,53,56 fidelity,139,207,216 flock dynamics,112 food,vii,x,8,14,16,17,21,23,24,26,30,74,84,114,130,146,175,190,197,199,200,201,224 food intake,146 forest ecosystem,86 forest formations,150,152,158,160,164 forest fragments,xi,150,164 France,18,33,45,46,48,63,166,191 fruits,viii,xii,190,192,201 G gazelle, 89 genotype,25,26,27,28,29,36,37,58,59,178,185,213 genus,viii,xiii,5,31,86,161,174,175,190,205,206,220,223 Germany,35,46,111,192 Giardia,viii,xiii,184,185,220,221,222,223,224,225,226 Giardia psittaci,220,224 giardiasis,vi,219,223,224,225 Giraffe,89,102 glucocorticoids,131,146 goose,vii,xi,112,115,116,117,118,120,128,136,138,139,140,141,144,146 granulomas,viii,2,20,21 grazing,59,70,80 greater white-fronted goose (Anser albifrons frontalis), 115 Greenland white-fronted goose (A. a. flavirostris), 115 greylag goose,vii,xi,112,117,140,141 Guinea,74,75,76,77,80,82,86,75,77 H habitat,xi,76,77,80,81,82,83,84,86,98,103,143,150,151,164,169 habitat occupation,xi,150,164 health,ix,41,44,46,47,48,50,51,54,56,57,59,64,66,67,70,91,92,176,177 health problems,50,51,177 heterogeneity,33,64,164 history,viii,x,xiii,73,98,99,103,106,118,119,135,137,141,190,199,206 hormones,70,131,146 human,vii,x,xii,5,73,80,82,83,84,86,87,92,93,94,96,97,101,102,106, ...
Chapter
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Oropharyngeal trichomonosis is a disease that affects wild and domestic birds. Some studies carried out in wildlife recovery centers pointed it out as the main cause of entrance of birds of prey due to infectious diseases. It causes small nodules and ulcers in the crop and other locations of the upper digestive system of the animals. These small lesions can coalesce and form large granulomas, which can provoke the death of the animal by starvation. Trichomonas gallinae is considered the etiological agent of the disease, a flagellated protozoon that is frequently found in the oral cavity of columbiformes, which are considered the main reservoir of the parasite. However, in the last decade, a great progress in the molecular characterization of this and other protozoa has been reached, and the number of genetic variants and even new species within the trichomonads that inhabit the avian oropharynx has expanded. In this review, we outline the latest descriptions of these parasites and their host spectrum; more than 10 genetic variants or new species are included. Although trichomonosis has been described in several groups of birds, the higher impact is usually found on Accipitriformes, Falconiformes and Strigiformes due to their predation or scavenging habits. Psittaciformes and Passeriformes also show clinical signs of the disease, and recently, several epidemic episodes of trichomonosis in fringilids were described across Europe and North America. In addition, chicks of endangered species like the Bonelli´s Eagle are frequently affected by the parasite, as several studies carried out in Spain and nearby countries have proved. In this review, we outline the most important features of the disease, including the biological, diagnosis and treatment options. Additionally, we will describe the recent scientific advances in the pathology, epidemiology and control of the disease.
... Agonistic encounters are known to be among the most potent stressors, activating the sympathico-adrenergic system and the hypothalamic-pituitary-adrenocortical (HPA) axis (De Vries et al., 2003;Sapolsky, 1992;von Holst, 1998;Wascher et al., 2008Wascher et al., , 2009). However, support by social allies ('social support') can significantly buffer HPA activation in response to social stressors (Abbott et al., 2003;De Vries et al., 2003;Frigerio et al., 2003;Hennessy et al., 2009;Scheiber et al., 2005a;von Holst, 1998) and decrease heart rate (Uchino et al., 1996;Wascher et al., 2012aWascher et al., , 2012b. Although physiological stress responses are generally adaptive in the short-term, a chronic elevation of glucocorticoids may have primates and rodents, Ferland and Schrader, 2011;Grippo et al., 2007;Hennessy, 1997;Pournajafi-Nazarloo et al., 2011;Smith et al., 2011) and birds (Banerjee and Adkins-Regan, 2011;Jones and Williams, 1992;Remage-Healey et al., 2003). ...
... The flock is subject to natural selection, especially by predation, and natural levels of parasite infection, as the geese are usually not treated against disease (Wascher et al., 2012a(Wascher et al., , 2012b. Approximately one third of all individuals is hand-raised (Hemetsberger et al., 2010), and all geese are well habituated to close human presence: they neither show avoidance when approached to a distance of 1.5 m, nor elevated levels of immuno-reactive corticosterone metabolites or significant heart rate changes (Frigerio et al., 2003;Scheiber et al., 2005a;Wascher et al., 2011). During the time of this study, the flock consisted of approximately 140 geese, which were all individually marked with coloured leg bands. ...
... The samples were frozen at −20 • C within 2 h of sampling, stored and subsequently sent to the Department for Behavioural Biology, University of Vienna for laboratory analyses. Samples were assayed with an enzyme immunoassay (5␤, 3␣, 11␤-diol glucocorticoid metabolite assay), which has been previously validated for geese (Frigerio et al., 2004;Möstl et al., 2005;Scheiber et al., 2005a). Intra-and interassay coefficients of variation were determined from homogenised pool samples (<15% and <25%, respectively). ...
Article
The presence of a social partner may significantly contribute to coping with stressful events, whereas dyadic separation generally increases glucocorticoid levels and, thereby, might also affect immune function and health. To study the covariation between social factors, immuno-reactive corticosterone metabolites, haematology and parasite product excretion patterns in a free-living, long-term monogamous bird, we separated pair mates in Greylag geese (Anser anser). We isolated the males of eight pairs for 48 hours to examine behavioural, adrenocortical, haematological and parasitological responses to mate removal in the female partners, and to social isolation in the males. Females showed no elevated levels of corticosterone metabolites in their droppings, but their haematocrit decreased during mate removal, whereas leucocyte number and heterophil/lymphocyte (H/L) ratio remained unchanged. In contrast, the socially isolated males excreted significantly elevated levels of corticosterone metabolites compared to baseline and showed a decrease in haematocrit as well as elevated leucocyte number and H/L ratio. In both sexes, the excretion of coccidian oocysts increased within 48 hours of the start of the separation, remained high one week after separation, and returned to baseline four weeks later. Described effects were generally more pronounced in males than in females. Our results suggest relatively swift potential health effects of mate loss and social isolation in an unfamiliar confinement in free-living geese.
... All individuals are marked with coloured leg rings and are habituated to the close presence of humans. They show neither increased excreted immunoreactive corticosterone metabolites in the faeces nor modifications of the heart rate when approached by familiar humans (Scheiber et al. 2005;Wascher et al. 2011). Social behaviour and individual life history have been monitored since 1973. ...
... steroid hormones) is well-documented (Nelson 1995;Hirschenhauser et al. 2013). In Greylag Geese, results from longterm research showed significant differences in both hormonal patterns and heart rates within the sexes depending on breeding and reproductive success (Kotrschal et al. 1998(Kotrschal et al. , 2000Hirschenhauser et al. 1999a, b;Hirschenhauser et al. 2000;Frigerio et al. 2004;Scheiber et al. 2005;Wascher et al. 2008Wascher et al. , 2012. In addition to hormonal patterns, effects of age and bonding duration may influence the behavioural coordination (Fowler 1995). ...
Article
Reproductive success in monogamous species is generally affected by both behavioural and hormonal fine-tuning between pair partners. Vigilance, defence and brooding of offspring are among the main parental investments, and often the sexes adopt different roles. In the present study, we investigate how sex differences in parental behaviour and family proximity in the socially monogamous Greylag Goose (Anser anser) affect gosling survival. During the reproductive season in spring 2013, we recorded the behaviour of 18 pairs with offspring and gosling survival in a semi-tame, long-term monitored, and individually marked flock of Greylag Geese in Grünau, Austria. We found that behavioural role differentiation between the parents varied with developmental phase, and thus with gosling age. Especially during the first 10 days after hatching, females were foraging more frequently than males, which were more vigilant and aggressive towards other flock members. Such differences between the sexes levelled out 20 to 30 days after hatching. In general, females stayed in closer proximity to their offspring than males. Gosling survival was high when the parents were relatively aggressive and emphasized vigilance rather than foraging behaviour. Hence, we show a direct link between pair partners’ quality of parental investment and gosling survival. Electronic supplementary material The online version of this article (10.1007/s10336-019-01638-x) contains supplementary material, which is available to authorized users.
... (c) Immuno-reactive corticosterone metabolites (CORTm) When goslings where 3, 9, 12, 17 and 22 days old, we collected a minimum of three dropping samples [33] of all individuals in their respective feeding areas over a 3 h period to determine baseline corticosterone metabolites. To determine the acute physiological stress response, we collected droppings for 3 h [33] immediately after the stress tests (see electronic supplementary material methods for details). ...
... (c) Immuno-reactive corticosterone metabolites (CORTm) When goslings where 3, 9, 12, 17 and 22 days old, we collected a minimum of three dropping samples [33] of all individuals in their respective feeding areas over a 3 h period to determine baseline corticosterone metabolites. To determine the acute physiological stress response, we collected droppings for 3 h [33] immediately after the stress tests (see electronic supplementary material methods for details). All droppings were frozen within 1 h, and later on analysed using an enzyme immuno assay (EIA, see electronic supplementary material methods for details). ...
Article
Full-text available
Natural populations are persistently exposed to environmental pollution, which may adversely impact animal physiology and behaviour and even compromise survival. Responding appropriately to any stressor ultimately might tip the scales for survival, as mistimed behaviour and inadequate physiological responses may be detrimental. Yet effects of legacy contamination on immediate physiological and behavioural stress coping abilities during acute stress are virtually unknown. Here, we assessed these effects in barnacle goslings (Branta leucopsis) at a historical coal mine site in the Arctic. For three weeks we led human-imprinted goslings, collected from nests in unpolluted areas, to feed in an abandoned coal mining area, where they were exposed to trace metals. As control we led their siblings to feed on clean grounds. After submitting both groups to three well-established stress tests (group isolation, individual isolation, on-back restraint), control goslings behaved calmer and excreted lower levels of corticosterone metabolites. Thus, legacy contamination may decisively change stress physiology and behaviour in long-lived vertebrates exposed at a young age.
... Hormone levels can be measured in several ways. In some cases, noninvasive sampling procedures such as corticoid determination in the faeces of birds offer the advantage that samples can be collected without stressing the birds (Möstl and Palme, 2002;Scheiber et al., 2005;Legagneux et al., 2011). ...
Article
Feather production is realised by gathering feathers from geese right as they start their natural moulting. The adequate gathering time coincides with the time of moulting. There is still scarce information as to whether or not gathering causes distress and pain to geese. A series of experiments was carried out by our research group to determine the effect of gathering on plasma corticosterone level in growing geese. In the present experiment, the reactions of five groups (two gathered and three not gathered groups) of 9-week-old Babat Hungarian Upgraded geese were compared regarding gathering. Blood samples were taken right before, during and 5 min, 1 and 3 h after gathering into heparinised tubes from all groups. The plasma concentration of corticosterone was determined by radioimmunoassay (RIA). The results show that the plasma concentration of corticosterone is high in the first sample of all groups but is significantly lower at subsequent blood samplings compared to the first samples, especially in gathered geese. Compared to the first sampling, we observed higher corticosterone levels in samples collected 1 and 3 h after gathering. This was true only for groups which were not gathered, especially for the group which was not given any antistress material. From these results it can be concluded that the handling of geese causes an elevation in plasma corticosterone level and that feather gathering does not result in a higher corticosterone level than the handling or catching of the bird. Therefore, it can be concluded that feather gathering - especially when it is done adequately in time - does not cause more distress than the handling or catching of the bird.
... There was considerable variability between individual samples (Fig. 4). This indicates that relying on individual samples could yield false results as shown for other species (Scheiber, Kralj & Kortrschal, 2005). Single samples may not be representative of the overall condition that necessitated our grouping of multiple samples from each individual. ...
Article
Fecal glucocorticoid metabolite (FGM) analysis provides a non-invasive method for studying the physiological response of wildlife to a variety of stressors and is a ground-breaking monitoring technique in wildlife management and conservation. The conservation benefits of successful wildlife translocation restocking efforts are significant but understandably stressful for the animals being captured, removed from familiar habitat, held in captivity in many cases and subsequently released into an unfamiliar environment. It is imperative that we identify non-invasive methods for evaluating stress in translocated animals, especially in endangered species. Twenty Grevy's zebra Equus grevyi were translocated to Meru National Park as part of a Kenya Wildlife Service re-population initiative. FGMs were monitored from the time of capture, during captivity and post-release as an indicator of the stress of translocation and acclimation to the new environment. FGMs from representative non-translocated zebra were used as a further control. When held in pens at Meru Park 3–4 and 5–6 weeks after capture, the zebra had higher FGMs (25.1±1.2 and 23.4±1.3 ng g−1) than either at the time of capture (14.6±2.1 ng g−1) or non-translocated controls (16.2±1.2 ng g−1). This suggests that the stress of captivity elevated FGMs. FGM concentrations returned to pre-capture concentrations c. 11–18 weeks after the zebra were released into Meru Park. The return of FGM concentrations to baseline suggests successful acclimation to the new environment. This study supports the use of FGM analysis as an assessment technique in wildlife management projects involving the movement of endangered large mammals with application for monitoring stress in a wide array of conservation projects involving translocation, reintroduction and rehabilitation.
... During social density stress, geese are fed with the same amount of food spread over about one quarter of the regular feeding area. This is perceived stressful by the geese and results in increased excretion of faecal immuno-reactive corticosterone metabolites (Scheiber et al., 2005a). To investigate stress responses to a predator, geese were exposed to a leashed dog for 4 minutes. ...
Article
Full-text available
Animals are hand-raised in a variety of contexts, including experimental research. This has been criticized frequently as producing animals with species-untypical behaviour. Here we compare life histories of 330 hand-raised and 631 gooseraised Greylag geese from a free-flying flock to determine whether hand-raising affected life history, reproductive variables and behaviour. We found little differences in life histories (e.g. male age, age at pair bond) or reproductive variables (e.g. number of eggs, egg weight, number of young hatched and fledged) of hand-raised and goose-raised geese. However, hand-raised females had lower life expectancies than goose-raised ones, mainly due to predation during breeding. Hand-raised geese were stressed significantly less during social, handling and predator stress, were attacked less by conspecifics and were less vigilant than goose-raised geese. We conclude that hand-raising resulted in geese with species-typical life histories but reduced stress responses. This makes hand-raised geese cooperative partners for research, but also more vulnerable when exposed to predators. Keywords: hand-raising; greylag goose; Anser anser ; life-history; reproductive success; stress
... The concentration of CMs varies between individual droppings excreted within a short time by the same individual (Baltic et al. 2005) because of pulsative excretion (Klasing 2005) or other factors. In accordance with Scheiber et al. (2005), we pooled and homogenized the 5-15 droppings of each dropping sample before lyophilization, extraction and analysis (Thiel et al. 2005b) to obtain an overall value of the concentration of CMs representative of a longer time span of several hours. This is in contrast to plasma samples, in which the concentration of corticosterone is measured at the time point of blood sampling. ...
Article
Montane and alpine habitats in Europe remained relatively undisturbed until the beginning of the last century. Today, outdoor recreation activities are a major economic factor in alpine regions. Many tourism areas coincide with winter habitats of shy and endangered species. The Western Capercaillie Tetrao urogallus has suffered from rapid population declines during recent decades over much of its range. In central Europe, many Capercaillie are exposed to intensive human recreation activities in their habitats, which may contribute to this decline. However, little is known about their susceptibility to human recreation activities. This study assessed whether human recreation in winter evokes physiological stress responses in several populations of Capercaillie. During two winters, we sampled 1130 Capercaillie droppings in Germany and Switzerland of populations at various distances from winter recreation activities and measured concentrations of faecal corticosterone metabolites. Capercaillie in relatively dense and homogeneous mountain forests dominated by Norway Spruce Picea abies showed markedly increased stress hormone levels closer to locations with winter recreation activity. However, this physiological response to human recreation was not detectable in forests dominated by various pine species and a heterogeneous structure. Capercaillie may be particularly sensitive to recreation because any factor affecting their fine-tuned physiological and behavioural adaptations to survive under harsh winter conditions may lead to harmful fitness costs.
... As urinary glucocorticoid excretion is faster than faecal excretion in birds (Möstl et al., 2005), but urine and faeces are excreted together, two peaks of corticosterone metabolites are observed in excreta: an earlier peak representing urinary excretion, and a later peak representing faecal excretion (Möstl et al., 2005; Rettenbacher et al. 2004). This point is not as important for the measurement of baseline concentrations, but the pattern of excretion must be considered if using faecal samples to measure an acute stress response (see Scheiber et al., 2005). Additionally, the type of food consumed and the digestive physiology of the studied birds must be considered when comparing faecal hormone concentrations between species, or temporally within species in which diet may change (Klasing, 2005). ...
Article
Full-text available
Physiological measurements of both stress and sex hormones are often used to estimate the consequences of natural or human-induced change in ecological studies of various animals. Different methods of hormone measurement exist, potentially explaining variation in results across studies; methods should be cross-validated to ensure that they correlate. We directly compared faecal and plasma hormone measurements for the first time in a wild free-living species, the Adelie penguin (Pygoscelis adeliae). Blood and faecal samples were simultaneously collected from individual penguins for comparison and assayed for testosterone and corticosterone (or their metabolites). Sex differences and variability within each measure, and correlation of values across measures were compared. For both hormones, plasma samples showed greater variation than faecal samples. Males had higher mean corticosterone concentrations than females, but the difference was only statistically significant in faecal samples. Plasma testosterone, but not faecal testosterone, was significantly higher in males than females. Correlation between sample types was poor overall, and weaker in females than in males, perhaps because measures from plasma represent hormones that are both free and bound to globulins, whereas measures from faeces represent only the free portion. Faecal samples also represent a cumulative measure of hormones over time, as opposed to a plasma ‘snapshot’ concentration. Our data indicate that faecal sampling appears more suitable for assessing baseline hormone concentrations, whilst plasma sampling may best define immediate responses to environmental events. Consequently, future studies should ensure that they select the most appropriate matrix and method of hormone measurement to answer their research questions.
... The flock is supplemented with pellets and grain twice daily at 0800 and 1500 hours during the winter months and at 1700 hours during the summer months. Both hand-raised and goose-raised flock members are habituated to the close presence of humans and they neither show avoidance if approached up to 1 m distance nor excrete elevated levels of corticosterone metabolites following such situations (Scheiber et al. 2005a) or significantly change HR when familiar humans approach (C.A.F. Wascher, unpublished data). ...
Article
As in most social groups, agonistic interactions of various intensities are common in a goose flock. This may cause social stress, modulating heart rate (HR), which may serve as a measure of energetic investment and also of individual emotional involvement. We investigated HR responses to social encounters in 24 free-living greylag geese in an intact social environment. We recorded 1602 social interactions of various intensities in which the focal individual either attacked another member of the flock or was attacked itself. We analysed five HR parameters (mean HR, maximum HR, HR increase, duration until maximum, time until the baseline value was reached again). Generally, HR scaled positively with increasing intensity of agonistic interactions as well as with increasing duration. Individuals showed higher HRs when attacking than when being attacked. In addition, focal individuals responded with a greater HR increase when confronted with an opponent winning a higher percentage of interactions than itself. Repeated agonistic interactions against a specific opponent were related to greater HR responses than single events and focal individuals responded more strongly to male opponents than to females. Our results indicate a differential HR response depending on the intensity and duration of an interaction as well as the identity of the opponent. This differential physiological investment may reflect differences in emotional involvement depending on the social context of a particular agonistic interaction.
... In geese, faecal samples are an integrated, proportional record of plasma glucocorticosterone and testosterone levels 30–180 min before defecation (Scheiber et al. 2005b). We collected faecal samples after handling and after feeding. ...
Article
Full-text available
Personality means suites of correlated behavioural traits, also referred to as "behavioural syndromes" or "personality dimensions". Across animal taxa similar combinations of traits seem to prevail, which may have proximate foundation in common neuroendocrine mechanisms. Hitherto, these have been rarely studied in intact social settings. We investigated personalities of greylag goose males from a free-roaming flock that shows complex social relationships. In connection with our longitudinal study on the consistency of behavioural and physiological responses to multiple challenges, we asked whether and how single, personality-related behavioural traits correlate with each other to form personality dimension(s). We tested whether these dimensions were related to physiological characteristics that previously showed limited plasticity (heart rate (HR), baseline and stress-induced excreted immuno-reactive corticosterone (BM), and testosterone metabolites levels) and, furthermore, to age, body measures, and dominance rank. Principal-components analysis based on behavioural variables revealed two factors: 51.1% of variability was explained by "aggressiveness" and a further 19.1% by "sociability". "Aggressiveness" comprised correlated measures of aggression, subordinance, boldness, vigilance, and proximity to the mate. This "aggressiveness" positively correlated with stress-induced BM levels, the HR increase during aggressive interactions, and with dominance rank, which may suggest proximate and functional contingencies of this personality dimension.
... Such validation experiments have been used in captive birds to infer the time lag required to detect a sharp increase in CORT measured in droppings (see for example [16] in starlings Sturnus vulgaris, [46] in mourning doves Zenaida macroura, [47] in the Northern spotted owl Strix occidentalis caurina, [25,26] in two goose species, see also [44] for a review). Injection of ACTH increased levels of CORT in droppings after $1 h in the upland goose Chloephaga picta [25] and after $2 h in the greylag goose Anser anser [21,26,40] which is consistent with our results in the greater snow goose. In sharp contrast with these results, we found that CORT levels in droppings started to increase as early as 6–10 min after capture in wild greater snow geese and was considerably elevated 40 minTable 1) and the time elapsed after capture. ...
Article
Full-text available
Baseline glucocorticoid (CORT) levels in plasma are increasingly used as physiological indices of the relative condition or health of individuals and populations. The major limitation is that CORT production is stimulated by the stress associated with capture and handling. Measuring fecal CORT is one way to solve this problem because elevation of fecal CORT usually does not occur before 1–12 h after a stressful event in captive animals. However, the effect of capture and handling on fecal CORT levels has seldom been investigated in the wild. In a first experiment, we validated that fecal CORT levels starts to increase in droppings (a mixture of fecal and urinary material) about 1–2 h following injection of CORT-release hormone (ACTH) in captive greater snow geese (Chen caerulescens atlantica). In a second experiment, we investigated whether dropping and plasma CORT were related and if the capture affected fecal CORT levels in wild birds. Baseline CORT was obtained by bleeding individuals within 4 min after capture. No relationship was found between baseline and CORT in droppings shortly after capture (<4 min). In addition, CORT levels in droppings increased linearly with time after capture and was already elevated by a factor two 40 min after capture. The different turnover time of CORT between urine and feces could explain such results. We conclude that droppings cannot provide an index of basal CORT levels in snow geese captured in the wild. Such a result contrast with previous studies conducted on habituated, captive animals. We thus recommend that use of droppings as a non-invasive technique to measure baseline CORT be restricted to non-manipulated individuals in the wild.
... To standardize daytime, droppings were always taken in the mornings between 9:00 and 11:00 a.m. We aimed at collecting three droppings from three different days per individual per week to cover within-individual variation (Scheiber et al., 2005). Sample sizes vary (Table 1) as we did not always succeed in collecting sufficient samples within the preset time window from all individuals, which was particularly difficult during incubation when collection was limited to breeding pauses and both, geese and ganders were usually more sensitive to the presence of an observing person. ...
Article
Full-text available
For successfully raising offspring, long-term monogamous pair partners need to be behaviorally and hormonally coordinated. In the monogamous, biparental greylag geese (Anser anser) a dyadic pairbond-specific measure, 'within-pair testosterone compatibility' (TC) indicated how closely synchronized are seasonal androgen levels, which co-varied with reproductive output. Males, in particular, were assumed to respond to their females' hormonal and fecundity phases. We now present experiments with biparental domestic geese (Anser domesticus) kept as pairs to ask whether TC occurs also in these generally polygynous animals. We further ask how different conditions of mate choice affect TC and whether established TC is maintained during a polygynous flock situation. We measured androgen metabolites (AM) non-invasively from individual droppings. In females, AM was related with gonadal activity as it increased after GnRH but not ACTH challenge. Females with preferred partners had higher maximum AM during egg laying and higher rates of initiating incubation than randomly paired females. Domestic ganders had seasonal AM patterns typical for polygynous males. Within-pair TC ranged from almost perfectly positive to non-correlated in domestic geese but mate choice did not explain TC variation. TC of previous pairs was generally reduced in the flock situation, probably confounded by factors of the social environment, i.e. mating opportunity and availability of multiple partners. On top of the underlying reproductive physiology our results suggest two episodic components of TC: a female androgen responsiveness to the preferred partner at least during egg formation, and the male's facultative potential to respond to her readiness to breed.
... The free-living flock of greylag geese in Grünau (Austria) is a well suited system for studying behavioural and physiological changes after challenges, because these geese are approachable and habituated to human presence [42] but are living in the full complexity of their social system. In 1973, a non-migratory flock of greylag geese was established in the valley of the river Alm in Upper Austria by the late Konrad Lorenz [20]. ...
Article
Stress responses involve autonomic, endocrine and behavioural changes. Each of these responses has been studied thoroughly in avian species, but hardly in an integrative way, in free-living birds. This is necessary to reveal the temporal dynamics of the stress response. Towards that goal, we recorded heart rate (HR) and behaviour in free-ranging male greylag geese (Anser anser) simultaneously over 2h. The geese were subjected to (a) unmanipulated control condition, (b) capture, handling and injection of ACTH, and (c) capture, handling and injection of a saline solution (SHAM). Fecal samples for the non-invasive determination of immuno-reactive glucocorticoid metabolite (BM) concentrations were collected for 7h thereafter. The SHAM control caused a significant BM increase, a transient increase in HR, an initial increase of preening behaviour and a delay in feeding. ACTH treatment, relative to SHAM, produced significantly higher BM concentrations, and activation of "displacement behaviours" such as wing flapping, body shaking and preening. Also, feeding activity as well as resting was postponed and/or lower for a longer period of time after ACTH than after SHAM. ACTH injection had a greater effect than SHAM injection on HR increase in the first hour, but particularly on HR decline in the second hour following the injection. Hence, glucocorticoids had time- and dose-dependent stimulatory and suppressive effects on cardiovascular activity and behaviour. HR dynamics after ACTH actually matched with behavioural dynamics: both were first enhanced and later suppressed, which is in alignment with adaptive stress management involving the fight-flight response and recovery from stress, respectively.
... Both hand-raised and goose-raised flock members are habituated to the close presence of humans. Geese do not show avoidance behaviour if approached up to 1 m distance, nor do they excrete elevated levels of immunoreactive corticosterone metabolites (Scheiber et al. 2005b ...
Article
It is known from primates that alliance partners may support each other's interests in competition with others, for example, through repeated agonistic attacks against a particular individual. We examined serial aggressive interactions between greylag goose families and other flock members. We found that repeated attacks towards the same individual were common and that up to five serial attacks by family members followed an initial attack. Family size did not affect the frequency of such serial attacks. Juvenile geese evidently benefited most from active social support through serial attacks. About 60% of the juveniles' lost primary interactions were subsequently reversed by another family member. This may be one of the reasons why juveniles rank higher in the social hierarchy than would be expected from their age and size alone. Losses in serial attacks predominantly occurred against other, presumably higher-ranking, family geese and ganders. We propose three major functions/consequences of serial attacks. Analogous to primates, serial attacks in greylag geese may serve to reinforce a losing experience of an opponent defeated in a preceding attack. On the side of the winning family, serial attacks may reinforce the experience of winning. Both winning and losing experiences are linked with physiological consequences in higher vertebrates, affecting the future social performance of winners or losers. Finally, serial attacks may signal the agonistic potential of a family to other flock members. This is supported by heart rate data, which indicate that greylags are competent to interpret third-party relationships.
... As the excretion of faeces or droppings may also vary with time of day, the two effects may either reinforce each other or cancel each other out. Further, at least in birds, it has been shown that hormone metabolite levels vary from dropping to dropping, suggesting that hormone metabolite levels should be based on several droppings (Klasing 2005;Scheiber, Kralj & Kotrschal 2005). ...
Article
1. Methods to measure metabolites of steroid hormones from faeces have become very popular in wildlife conservation and ecology, because they allow gathering physiological data without the necessity to capture the animals. However, this advantage comes at costs that are particularly relevant when studying free-living animals in their natural environments. Previous methodological reviews have stressed the importance of validations to prove that real metabolites of the hormone in question are measured, but the research community has largely ignored further caveats relating to sex, diet, metabolic rate and individual differences in hormone metabolite formation.
... To avoid the effect of diurnal variation, individual droppings were collected after the morning food provisioning until noon (Hirschenhauser et al. 2005). We aimed at collecting up to 3 droppings per individual per week to cover within-individual variation (Scheiber, Kralj, and Kotrschal 2005). ...
Article
Full-text available
In long-term monogamous birds reproductive success varies considerably among pairs. Determinants of reproductive success may be individual as well as pair-specific parameters, including the degree of compatibility and coordination among pair partners. However, little is known about the consistency of partner compatibility with regards to social contexts and life-history changes. In the long-term monogamous, biparental greylag geese, reproductive success was previously found to correlate positively with the degree of hormonal compatibility within pairs. In the present study, we analyzed the degree of within-pair testosterone covariation (TC) in relation to individual and pair-specific life history and social instability. We found that greylag goose pairs facing active social challenge had lower degrees of TC than those in unchallenged pair-bonds, whereas the permanent attachment of a third individual to an existing pair or the number of previous partners did not correspond with changed TC. Furthermore, TC decreased with increasing pair-bond duration and increased with female age but was not related with age of the male partner or other life-history parameters. Hence, our data suggest that hormonal partner compatibility in greylag geese is not a stable trait, but rather reflects a pair's status quo, which may be particularly affected by the stability of the social environment. Copyright 2009, Oxford University Press.
... The flock is supplemented with pellets and grain twice daily at 0800 and 1500 hours during the winter months and at 0800 and 1700 hours during the summer months. Both hand-raised and goose-raised flock members are habituated to the close presence of humans and they do not show avoidance, changes in agonistic behavior [29], elevated levels of corticosterone metabolites [30] or HR change when familiar humans approach to within 1 m [2]. ...
Article
Full-text available
Social stressors are known to be among the most potent stressors in group-living animals. This is not only manifested in individual physiology (heart rate, glucocorticoids), but also in how individuals behave directly after a conflict. Certain 'stress-related behaviors' such as autopreening, body shaking, scratching and vigilance have been suggested to indicate an individual's emotional state. Such behaviors may also alleviate stress, but the behavioral context and physiological basis of those behaviors is still poorly understood. We recorded beat-to-beat heart rates (HR) of 22 greylag geese in response to agonistic encounters using fully implanted sensor-transmitter packages. Additionally, for 143 major events we analyzed the behavior shown by our focal animals in the first two minutes after an interaction. Our results show that the HR during encounters and characteristics of the interaction predicted the frequency and duration of behaviors shown after a conflict. To our knowledge this is the first study to quantify the physiological and behavioral responses to single agonistic encounters and to link this to post conflict behavior. Our results demonstrate that 'stress-related behaviors' are flexibly modulated by the characteristics of the preceding aggressive interaction and reflect the individual's emotional strain, which is linked to autonomic arousal. We found no support for the stress-alleviating hypothesis, but we propose that stress-related behaviors may play a role in communication with other group members, particularly with pair-partners.
... At the time of the study the flock consisted of approximately 150 individuals, marked with colored leg bands for identification. Geese are habituated to the close presence of humans and do not show avoidance if approached up to 1 m distance, nor do they excrete elevated levels of corticosterone metabolites following such situations (Scheiber, Kralj, & Kotrschal, 2005). ...
Article
Full-text available
Adequate short-term responses to stressors are of great importance for the health and well-being of individuals and factors modulating the physiological stress response (e.g., controllability, suddenness, familiarity) of a stimulus are well described under laboratory conditions. In the present study we aimed at investigating the stress response in greylag geese (Anser anser) in the field, confronting individuals with naturally occurring stressors. We measured beat-to-beat heart rate (HR) via fully implanted transmitters during three different experimental challenges: (1) catching and holding, (2) confrontation with a model predator, and (3) approach by different humans. We compared this to a control period and HR during agonistic encounters, a naturally occurring stressor. All three experimental situations evoked a HR increase. Highest HR responses were elicited by catching and holding the animals. In the third experiment, HR responses were greatest when the geese were approached by a human stranger (i.e., somebody the geese have never seen before). Hence, geese discriminated between different kinds of stressors and adjusted their physiological response depending on the type of stressor. Our results show that geese were able to discriminate between individual humans. In line with a number of lab studies, we suggest that particularly the controllability of certain situation determines the intensity of the HR response, also in a natural setting in the field.
... Such validation experiments have been used in captive birds to infer the time lag required to detect a sharp increase in CORT measured in droppings (see for example [16] in starlings Sturnus vulgaris, [46] in mourning doves Zenaida macroura, [47] in the Northern spotted owl Strix occidentalis caurina, [25,26] in two goose species, see also [44] for a review). Injection of ACTH increased levels of CORT in droppings after $1 h in the upland goose Chloephaga picta [25] and after $2 h in the greylag goose Anser anser [21,26,40] which is consistent with our results in the greater snow goose. In sharp contrast with these results, we found that CORT levels in droppings started to increase as early as 6–10 min after capture in wild greater snow geese and was considerably elevated 40 minTable 1) and the time elapsed after capture. ...
Article
Baseline glucocorticoid (CORT) levels in plasma are increasingly used as physiological indices of the relative condition or health of individuals and populations. The major limitation is that CORT production is stimulated by the stress associated with capture and handling. Measuring fecal CORT is one way to solve this problem because elevation of fecal CORT usually does not occur before 1-12h after a stressful event in captive animals. However, the effect of capture and handling on fecal CORT levels has seldom been investigated in the wild. In a first experiment, we validated that fecal CORT levels starts to increase in droppings (a mixture of fecal and urinary material) about 1-2h following injection of CORT-release hormone (ACTH) in captive greater snow geese (Chen caerulescens atlantica). In a second experiment, we investigated whether dropping and plasma CORT were related and if the capture affected fecal CORT levels in wild birds. Baseline CORT was obtained by bleeding individuals within 4 min after capture. No relationship was found between baseline and CORT in droppings shortly after capture (<4 min). In addition, CORT levels in droppings increased linearly with time after capture and was already elevated by a factor two 40 min after capture. The different turnover time of CORT between urine and feces could explain such results. We conclude that droppings cannot provide an index of basal CORT levels in snow geese captured in the wild. Such a result contrast with previous studies conducted on habituated, captive animals. We thus recommend that use of droppings as a non-invasive technique to measure baseline CORT be restricted to non-manipulated individuals in the wild.
... There was considerable variability between individual samples (Fig. 4). This indicates that relying on individual samples could yield false results as shown for other species (Scheiber, Kralj & Kortrschal, 2005). Single samples may not be representative of the overall condition that necessitated our grouping of multiple samples from each individual. ...
Article
Fecal glucocorticoid metabolite (FGM) analysis provides a non-invasive method for studying the physiological response of wildlife to a variety of stressors and is a ground-breaking monitoring technique in wildlife management and conservation. The conservation benefits of successful wildlife translocation restocking efforts are significant but understandably stressful for the animals being captured, removed from familiar habitat, held in captivity in many cases and subsequently released into an unfamiliar environment. It is imperative that we identify non-invasive methods for evaluating stress in translocated animals, especially in endangered species. Twenty Grevy's zebra Equus grevyi were translocated to Meru National Park as part of a Kenya Wildlife Service re-population initiative. FGMs were monitored from the time of capture, during captivity and post-release as an indicator of the stress of translocation and acclimation to the new environment. FGMs from representative non-translocated zebra were used as a further control. When held in pens at Meru Park 3–4 and 5–6 weeks after capture, the zebra had higher FGMs (25.1±1.2 and 23.4±1.3 ng g−1) than either at the time of capture (14.6±2.1 ng g−1) or non-translocated controls (16.2±1.2 ng g−1). This suggests that the stress of captivity elevated FGMs. FGM concentrations returned to pre-capture concentrations c. 11–18 weeks after the zebra were released into Meru Park. The return of FGM concentrations to baseline suggests successful acclimation to the new environment. This study supports the use of FGM analysis as an assessment technique in wildlife management projects involving the movement of endangered large mammals with application for monitoring stress in a wide array of conservation projects involving translocation, reintroduction and rehabilitation.
... At the research station, the flock is supplemented with pellets and grain twice daily at 0800 and 1500 hours during the winter months and at 1700 hours during the summer months. if approached up to a distance of 1 m nor excrete elevated levels of corticosterone metabolites following such situations (Scheiber et al., 2005) or significantly change heart rate when familiar humans approach (Wascher et al., 2011). New Year's Eve celebrations and fireworks are held in several nearby villages, including Grünau im Almtal and directly at the Almsee, where the geese roost at night. ...
Article
Anthropogenic disturbances are a major concern for the welfare and conservation of wildlife. We recorded heart rate and body temperature of 20 free-living greylag geese in response to a major regularly re-occurring anthropogenic disturbance-New Year's Eve fireworks. Heart rate and body temperature were significantly higher in the first and second hour of the new year, compared with the same hour on the 31st of December, the average during December and the average during January. Heart rate and body temperature was not significantly affected by sex or age. From 0200 to 0300 onwards, 1st of January heart rates did not significantly differ from the other periods; however, body temperatures were significantly increased until 0300-0400. From 0400 to 0500, heart rate was not affected by any of the investigated factors, whereas body temperature was significantly increased on the 1st of January compared with the 31st of December and the December average but not compared with the January average. To conclude, our results show that New Year's Eve fireworks cause a substantial physiological response, indicative of a stress response in greylag geese, which is costly in terms of energy expenditure.
... Hirschenhauser et al. 12 provide an overview of noninvasive hormone research in greylag geese (Anser anser), probably the bird species for which the most extensive data regarding noninvasive hormone research are available so far. Finally, Scheiber et al. 13 explore how many samples from an individual are necessary to measure an acute stress response in greylag geese. Although the focus of all these contributions was on birds, most of the issues and problems discussed apply equally well to mammals and other vertebrates. ...
... However, it is not likely that this loss of data in the control and mate present condition remarkably affected the results. Scheiber et al. (2005b) determined in greylag geese that three samples were sufficient to consistently assess differences in CM between a control condition and after a social density stress, when CM maxima were used for analysis. Four or more samples were required when working with the mean. ...
Research
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book chapter, on an experiment with Great tits of lines selected for fast and slow exploratory behaviour
... These variables create discrepancies between circulating glucocorticoids and FGM that are not attributable to stressors. For example, FGM concentration in feces can vary considerably with individual diet (Dantzer, McAdam, Palme, Boutin, & Boonstra, 2011) and gut transport time (Scheiber, Kralj, & Kotrschal, 2005), even among fecal samples collected relatively close together in time. To control for the confounding effect of diet and gut transport time on FGM levels, we only included individuals we were able to sample at least three times over the sampling period. ...
Preprint
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Glucocorticoid production is often indicative of internal state that underpins movement and resulting habitat selection. Habitat selection is adaptive behaviour, but habitats where animals exhibit atypical glucocorticoid production are often associated with low fitness. Discrepancies between poor fitness outcomes and purported adaptive behaviour have contributed to a lack of consensus about the ecological and evolutionary implications of glucocorticoid production. We aim to demonstrate the adaptive ecological and evolutionary roles of glucocorticoids by integrating stress physiology with habitat selection theory. First, we show how habitat selection theory can benefit from a mechanistic understanding of the relationships between stressors, internal state, and habitat selection. We show that glucocorticoids drive everything from short-term locomotion to large-scale movements. In turn, these movements produce familiar patterns of adaptive habitat selection like habitat specialization and migration. Populations arrive at these evolutionarily stable habitat selection strategies by responding to stressors like predation and food availability. To quantify responses to stressors, we show how to parameterize glucocorticoid data in habitat selection models. Modelling the ecological and evolutionary patterns that make habitat selection adaptive also help clarify relationships between glucocorticoids, stress, and fitness. Our approach delivers a practical framework for testing existing hypotheses about habitat selection and stress physiology. Our framework can also be applied to new questions that integrate both, with the potential to understand adaptations of populations to their environments, and implications of stressors and habitat selection for ecosystem functioning.
... Glucocorticoid measures can be a useful marker of physiological state, especially when assessed noninvasively (Schwarzenberger, 2007), but need to be interpreted correctly. Increases in concentrations are associated with acute (Scheiber et al., 2005;Viljoen et al., 2008;Voellmy et al., 2014) and chronic (Gobush et al., 2008;Blickley et al., 2012;Parry-Jones et al., 2016) stress, but also can occur in animals coping appropriately with day-to-day challenges, including positive stimuli such as pleasure, excitement and arousal (Ralph and Tilbrook, 2016). They may also reflect normal physiological states; e.g. during the estrous cycle (Fanson et al., 2014) and pregnancy (Kersey et al., 2011;Marciniak et al., 2011). ...
Article
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Additional measures of well-being would be beneficial to the management of a variety of species in human care, including elephants. Immunoglobulin A (IgA) is an immune protein associated with pathogen defense, which has been demonstrated to decrease during times of stress, and increase in response to positive stimuli. This paper describes the development and validation of an enzyme immunoassay (EIA) for the quantification of Asian elephant (Elephas maximus) IgA in feces, saliva, urine, and serum. Samples were collected weekly from four females for 6 months to assess IgA and glucocorticoid (GC) concentrations, establish relationships between these two biomarkers, and determine variability in IgA within and between individuals, and across sample types. IgA was quantified in all four sample types, although urinary concentrations were low and sometimes undetectable in individual samples. Concentrations were highly variable within and between individuals, with fecal, salivary and serum IgA, and fecal, salivary and urinary GCs all differing significantly across individuals. Contrary to previous findings, IgA and GC were generally not correlated. Serum IgA was less variable within individuals, with the exception of one female that experienced a brief illness during the study. However, marked inter-individual differences were still apparent. When data from all individuals were combined, fecal IgA was significantly predicted by salivary and urinary IgA; however, this relationship did not hold when individuals were analyzed separately. Analysis of a fifth female that exhibited a more severe systemic illness demonstrated clear increases in fecal IgA and GC, suggesting these may also be useful health biomarkers. Further investigation is needed to determine what sample type is most reflective of biological state in elephants, and how IgA concentrations are associated with health and positive and negative welfare states. Based on observed variability, a longitudinal approach likely will be necessary to use IgA as a measure of well-being.
... We did not collect samples from the 3 juvenile geese, as they were not banded at that time and samples could not be individually assigned, as well as from 1 adult goose that only defecated into the pond. We attempted to collect a minimum of 2 samples per individual within 3 h after feeding, as CORT concentrations in individual samples are highly variable in geese (Scheiber et al., 2005a). This, however, was not always possible (range 1-3 and mean ± SD 1.67 ± 0.724). ...
Article
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Chronic stress—or, more appropriately, “allostatic overload”—may be physiologically harmful and can cause death in the most severe cases. Animals in captivity are thought to be particularly vulnerable to allostatic overload due to artificial housing and group makeup. Here we attempted to determine if captive greylag geese (Anser anser), housed lifelong in captivity, showed elevated levels of immunoreactive corticosterone metabolites (CORT) and ectoparasites in dropping samples as well as some hematological parameters (hematocrit, packed cell volume, total white blood cell count [TWBC], and heterophil:lymphocyte ratio [H:L]). All of these have been measured as indicators of chronic stress. Furthermore, we correlated the various stress parameters within individuals. Captive geese showed elevated values of CORT and ectoparasites relative to a wild population sampled in the vicinity of the area where the captive flock is held. The elevated levels, however, were by no means at a pathological level and fall well into the range of other published values in wild greylag geese. We found no correlations between any of the variables measured from droppings with any of the ones collected from blood. Among the blood parameters, only the H:L negatively correlated with TWBC. We examine the problem of inferring allostatic overload when measuring only 1 stress parameter, as there is no consistency between various measurements taken. We discuss the different aspects of each of the parameters measured and the extensive individual variation in response to stress as well as the timing at which different systems respond to a stressor and what is actually measured at the time of data collection. We conclude that measuring only 1 stress parameter often is insufficient to evaluate the well-being of both wild and captively housed animals and that collecting behavioral data on stress might be a suitable addition. © 2015 American Society of Animal Science. All rights reserved.
... There was considerable variability between individual samples (Fig. 4). This indicates that relying on individual samples could yield false results as shown for other species (Scheiber, Kralj & Kortrschal, 2005). Single samples may not be representative of the overall condition that necessitated our grouping of multiple samples from each individual. ...
... We did not collect samples from the 3 juvenile geese, as they were not banded at that time and samples could not be individually assigned, as well as from 1 adult goose that only defecated into the pond. We attempted to collect a minimum of 2 samples per individual within 3 h after feeding, as CORT concentrations in individual samples are highly variable in geese (Scheiber et al., 2005a). This, however, was not always possible (range 1-3 and mean ± SD 1.67 ± 0.724). ...
Article
Full-text available
Chronic stress-or, more appropriately, "allostatic overload"-may be physiologically harmful and can cause death in the most severe cases. Animals in captivity are thought to be particularly vulnerable to allostatic overload due to artificial housing and group makeup. Here we attempted to determine if captive greylag geese (), housed lifelong in captivity, showed elevated levels of immunoreactive corticosterone metabolites (CORT) and ectoparasites in dropping samples as well as some hematological parameters (hematocrit, packed cell volume, total white blood cell count [TWBC], and heterophil:lymphocyte ratio [H:L]). All of these have been measured as indicators of chronic stress. Furthermore, we correlated the various stress parameters within individuals. Captive geese showed elevated values of CORT and ectoparasites relative to a wild population sampled in the vicinity of the area where the captive flock is held. The elevated levels, however, were by no means at a pathological level and fall well into the range of other published values in wild greylag geese. We found no correlations between any of the variables measured from droppings with any of the ones collected from blood. Among the blood parameters, only the H:L negatively correlated with TWBC. We examine the problem of inferring allostatic overload when measuring only 1 stress parameter, as there is no consistency between various measurements taken. We discuss the different aspects of each of the parameters measured and the extensive individual variation in response to stress as well as the timing at which different systems respond to a stressor and what is actually measured at the time of data collection. We conclude that measuring only 1 stress parameter often is insufficient to evaluate the well-being of both wild and captively housed animals and that collecting behavioral data on stress might be a suitable addition.
... As capture and handling of the animals is omitted, stress measurements from scats are unaffected by the observer and thus reflect the actual stress level of the animal more accurately (Kotrschal et al. 1998). Moreover, glucocorticoid metabolites in scats are pooled over a certain period, determined by gut passage time and dynamics of excretion (Scheiber et al. 2005). Thus, hormone concentrations in scats represent an assessment of chronic stress. ...
Article
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Human disturbance is thought to be a major source of stress for animals but breeding status, social interactions and food availability are also potential sources. Long-lasting stress may adversely affect the fitness of animals and for that reason the evaluation of stressors is important for conservation of threatened species. The aim of our study was therefore to assess which factors cause stress in wolves (Canis lupus). We evaluated the stress levels of wolves from six packs by measuring the concentration of glucocorticoid metabolites in 59 faecal samples with a Cortisol enzyme-immunoassay. During the breeding season, stress hormone concentration was higher than during the rest of the year, with two peaks around mating and begin of denning, respectively. Multiple regressions ranked by AIC showed that breeding had the highest impact on the wolves' stress levels, followed by human activity, pack size, and prey density. We conclude that human activity is only one of several factors contributing to stress in wolves and that intraspecific competition during breeding is likely to cause elevated levels of glucocorticoids.
... Methods similar to those used for quantifying cortisol in mammals have been developed to assay this hormone or its metabolites in the plasma and feces of birds Rettenbacher and Palme, 2009). As in mammals, levels of corticosterone and its metabolites in bird plasma and feces reflect events occurring over the short term, within a few hours to a day prior to collection of the specimen (Romero and Reed, 2005;Scheiber et al., 2005). Corticosterone concentration in feathers has the potential to reflect life events over longer term intervals (weeks to months), in correlation with the duration of feather growth, and recently Bortolotti et al. (2008Bortolotti et al. ( , 2009) reported such measurements. ...
... Increased ECM concentrations were reported in response to a wide variety of stressors in several avian species. Stressors include weather conditions (Frigerio et al. 2004) and group density (Scheiber et al. 2005) for greylag geese (Anser anser), breeding in the California spotted owl, (Tempel and Gutierrez 2004), and separation of pair-housed roosters in the domestic chicken . However, none of these studies demonstrate a quantifiable relationship between the stressor and response. ...
Article
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Cook, N. J. 2012. Review: Minimally invasive sampling media and the measurement of corticosteroids as biomarkers of stress in animals. Can. J. Anim. Sci. 92: 227�259. The measurement of corticosteroid hormones is commonly used as a biomarker of an animal’s response to stress. The difficulties in obtaining blood samples and the recognition of the stressor effect of blood sampling are primary drivers for the use of minimally invasive sample media. In mammals these include saliva, feces, urine, hair, and milk. In birds, samples include excreta, feathers, egg yolk and albumin. In fish, corticosteroids have been measured in excreta and swim-water. Each of these sample media incorporate corticosteroids in accordance with the processes by which they are formed, and this in turn dictates the periods of adrenocortical activity that each sample type represents. Cortisol in saliva represents a time-frame of minutes, whereas the production of feces may be hours to days depending on the species. The longest time-integrations are for hair and feathers which could be over a period of many weeks. The sample media also determines the structural changes that may occur via processes of conjugation to glucuronides and sulfides, metabolic conversion via enzymatic action, and bacterial breakdown. Structural changes determine the optimum methodologies used to measure corticosteroid hormones. In most sample media, measurement of a specific corticosteroid is a requirement depending on the species, e.g., cortisol in most mammals, or corticosterone in birds. However, in samples involving products of excretion, methodologies that measure a broad range of structurally related compounds are probably optimal. The utility of minimally invasive sample media as biomarkers of stress responses depends on the degree to which the corticosteroid content of the sample represents adrenocortical activity. Commonly, this involves comparisons between corticosteroid concentrations in blood plasma with concentrations in the alternative sample media. This review focuses on the methodological and biological validation of corticosteroid measurements in minimally invasive samples as biomarkers of adrenocortical responses to stress.
... Hirschenhauser et al. 12 provide an overview of noninvasive hormone research in greylag geese (Anser anser), probably the bird species for which the most extensive data regarding noninvasive hormone research are available so far. Finally, Scheiber et al. 13 explore how many samples from an individual are necessary to measure an acute stress response in greylag geese. Although the focus of all these contributions was on birds, most of the issues and problems discussed apply equally well to mammals and other vertebrates. ...
Article
Covariation of individual responses to different fear-eliciting situations is expected to manifest in general “fearfulness syndrome.” We tested for the existence of such a syndrome in wild-caught captive greenfinches. We assessed the propensity to give distress calls at handling, latency to feed at the presence of a predator image, and changes in locomotor activity in response to distress calls of conspecifics. Additionally, we measured the frequency of flapping flight movements against cage bars and tendency to damage tail feathers in captivity as indicators of the ability of birds to cope with captive conditions. As a proxy of neuroendocrine activity (an expected covariate of fearfulness), we measured the amount of stress hormone corticosterone deposited into feathers grown during captivity. All the behavioral traits were individually repeatable in time, but there were no correlations between them. Lack of the behavioral syndrome for fearfulness was also revealed by structural equation modelling. The findings of this experiment challenge the concept of a single internal variable responsible for fearfulness and support the proposed multidimensional nature of fear responses.
Chapter
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Convergent social structures can be found in taxa that split a long time ago, for example more than 230 Mio years ago as in the case of mammals and birds. Such convergence is explained by common selection regimes, as all social systems are shaped by sex-specific tactics and strategies to optimise their reproductive success. In addition, the major social mechanisms, brain and physiology, are highly conserved throughout the vertebrates. Manoeuvring social contexts tends to be energetically costly and, hence, favours efficient decision-making. Therefore, at least in vertebrates, complex social systems generally select for social cognition. As an example for social convergence between mammals and birds, we introduce the surprisingly complex social system of greylag geese, featuring components such as a female-bonded clan structure, long parent-offspring relationships, as well as elaborate and highly functional patterns of mutual social support. Our results show that partners in reproductively successful goose pairs are in hormonal synchrony and provide social support to each other. We suggest that social support may be a major structuring principle of other social systems with long-term individualized and valuable partnerships as well. In general, individual performance in social systems is determined by the interplay between proximate mechanisms and ultimate functions.
Chapter
This chapter addresses three key uses of captive birds by humans: (i) selective breeding for productivity and appearance and the potential for genetic disorders, (ii) biomedical research and testing and (iii) wild bird trapping and trading. These very different uses have been selected because, although birds have been used in these ways for hundreds or thousands of years, rapid legal, scientific and economic developments are now placing unprecedented pressure on the birds involved.
Article
A large body of literature demonstrates the adaptive benefits of social relationships between kin, including fitness and survival. Given that most social mammals are characterized by male-biased dispersal, the majority of research on kin selection and associated advantages focuses on social relationships between female kin. Meanwhile, research on social relationships between adult male and female kin has primarily focused on inbreeding avoidance or the benefit to adult sons, with less attention on potential advantages these social relationships may provide females. The general pattern of male dominance over females in most mammal species suggests that females may benefit from protective associations with adult male kin. Using 43 years of behavioural data on the wild chimpanzees, Pan troglodytes schweinfurthii, of Gombe National Park, Tanzania, we examined association patterns between females and their adult maternal male kin. We specifically focused on how these associations may represent a trade-off between inbreeding avoidance and protection for females, particularly against infanticide. In accordance with inbreeding avoidance, we predicted that females’ association with adult kin would decrease when they were maximally tumescent, signalling sexual receptivity. To determine whether female–male kin associations provide protection to females, we examined female associations with adult male kin during their first year postpartum when infants are most vulnerable to infanticide. We predicted that during this first year postpartum, females would have a higher association with male kin than with unrelated males. We found that females associated more with adult sons and brothers than with unrelated males when they did not have a sexual swelling. Female association increased with all males across tumescence but females associated less with their brothers than they did with their sons and unrelated males when they were maximally tumescent, providing equivocal support for the inbreeding avoidance hypothesis. Furthermore, females associated more with both sons and brothers than with unrelated males in the first 6 months of the postpartum period. Higher association with brothers, relative to unrelated males, persisted throughout the first year postpartum. Together, these results speak to the cost–benefit trade-off in female and adult male kin associations, highlighting the potential protective advantage for females, especially during the postpartum period.
Article
Glucocorticoid hormones (GCs) are important mediators of physiological and behavioral responses to stress. While many studies have evaluated the environmental, behavioral, or physiological correlates of GCs and their effects on reproductive performances, further work is needed to clarify the relationship between GCs and fitness. Assessing the effects of increased GC levels on specific behaviors of breeding animals should improve our understanding of how GCs affect parental care. In this experimental study, we measured the effects of an experimental increase in corticosterone (CORT, the main avian GC) levels on the behavior of free-living male Ad,lie penguins (Pygoscelis adeliae) within the colony, their reproductive output, and the indirect consequences of both on the behavior of their partners. We show that increased CORT levels in males decreased their foraging time at sea while increased their attendance at the nest, although their attentiveness toward the nest itself decreased. In addition, treated males spent more time on comfort behaviors (e.g., preening), vocalizing, and engaging in positive social interactions relative to controls. Treatment further affected the behavior of their partners, but not chick begging and feeding rates. Penguins with increased CORT levels also exhibited decreased reproductive output. Previous studies of Ad,lie penguins in different life history stages and environmental conditions suggest that the consequences of CORT treatment on reproductive performance are context-dependent. In addition to the potential delay in the effects of increased CORT levels on reproduction, this context dependence should be taken into account when studying the behavior of free-living animals in relation to stress-inducing situations.
Article
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The mouthbrooding cichlid Tropheus moorii exhibits an exceptional degree of maternal in-vestment. Females produce very large eggs, which are incubated for a period of six weeks, and they feed their young in the mouth while starving themselves. Only very few fish species are known to feed their young. We hypothesized that feeding may either (1) benefit females directly if young develop faster, or (2) provide a size advantage to young. To distinguish be-tween these mutually non-exclusive hypotheses, we measured costs and benefits arising for mouthbrooding females when feeding their young. Field observations revealed that mouth-brooding females reduced bite rates, locomotion and territorial defence compared to non-brooding adults. Feeding rates correlated positively with locomotion, as fish moving around more also spent more time with territory defence and other social interactions. This suggests that buccal feeding is costly when compared to mere incubation without feeding the young. In an experiment, in which we controlled the access of females to food, we showed that these costs are apparently not counterbalanced by a benefit to females through a shorter incubation duration. Rather, fed young were larger, heavier and had higher burst-swimming speeds. The extreme maternal investment of T. moorii appears to yield fitness benefits to females by pro-ducing larger and stronger young, which consequently should have better survival chances in their natural environment.
Data
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The Supplementary Tables and References list published papers dealing with faecal cortisol/corticosterone metabolites in different species grouped by class/order/family It's regularily updated now - see last update 27th Feb 2020!
Book
The flock of greylag geese established by Konrad Lorenz in Austria in 1973 has become an influential model animal system and one of the few worldwide with compelte life history data spanning several decades. Based on the unique records of almost 1000 free-living greylag geese, this is a synthesis of more than 20 years of behavioural research. It provides a comprehensive overview of a complex bird society, placing it in an evolutionary framework and drawing on a range of approaches, including behavioural (personality, aggression, pair bonding and clan formation), physiological, cognitive and genetic. With contributions from leading researchers, the chapters provide valuable insights into historical and recent research on the social behaviour of geese. All aspects of goose and bird sociality are discussed in the context of parallels with mammalian social organisation, making this a fascinating resource for anyone interested in integrative approaches to vertebrate social systems.
Article
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Living in groups has various advantages and disadvantages for group members. We investigated the fitness consequences of early social connectivity (normalized Freeman degrees based on nearest neighbour data), physiology (levels of excreted corticosterone metabolites assayed from droppings), and agonistic interactions in a group of free-ranging greylag geese (Anser anser). Forty-four greylag geese below 3 years of age were observed in three different seasonal phases: during the re-aggregation of the flock in autumn, at the end of the winter and during the forthcoming breeding season. We show that corticosterone metabolite levels and initiated and received aggression increased with increasing social connectivity. Individuals had higher connectivity scores in the winter flock than during the mating and breeding seasons. One-year old juveniles were more connected than 2- and 3-year old individuals. In addition, we examined the link between social connectivity during early development and reproductive success several years later. We found that birds with greater connectivity early in life attempted to breed at a younger age. Furthermore, successful breeders with higher early connectivity scores had higher numbers of fledged goslings. Our results show that social context in early life stages may have long-term effects on individual fitness.
Article
Reproduction is one of the most energetically costly life history stages, which impose constraints, even outside the breeding period. Capital breeders typically accumulate energy in preparation for reproduction and the amount of body mass gain prior to reproduction partly determines reproductive outcome in such species. Understanding the physiological and behavioral interplay that governs energy storage is thus essential. Pleiotropic hormones such as glucocorticoids can modulate diel and seasonal energy allocation in vertebrates. Baseline corticosterone (CORT, the main glucocorticoid hormone in birds) fluctuation can induce changes in foraging behavior and/or energy storage. In this experiment, we slightly elevated CORT levels and monitored body mass and foraging behavior prior to reproduction in semi-captive greylag geese. Birds treated either with CORT or placebo pellets inserted subcutaneously were monitored during 21 days. Same individuals were sequentially submitted to both treatments. The increase of CORT levels measured in either fecal or blood samples confirmed the slight CORT elevation in treated birds. Foraging behaviors increased (up to 9%) in the CORT treated group compared to controls only during morning observations. Birds treated with CORT increased their body mass gain by 6.3% compared to controls. This effect lasted during the first 11 days after pellet implementation. We thus confirm the central role of glucocorticoids on foraging behaviors and body mass gain in pre-nesting birds. This study opens new avenues to manipulate body condition in large-bird species.
Technical Report
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Updated tables, figures and references of Palme, 2019, and the respective supplements (Date: 1st July 2022)
Article
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The mouthbrooding cichlid Tropheus moorii exhibits an exceptional degree of maternal in-vestment. Females produce very large eggs, which are incubated for a period of six weeks, and they feed their young in the mouth while starving themselves. Only very few fish species are known to feed their young. We hypothesized that feeding may either (1) benefit females directly if young develop faster, or (2) provide a size advantage to young. To distinguish be-tween these mutually non-exclusive hypotheses, we measured costs and benefits arising for mouthbrooding females when feeding their young. Field observations revealed that mouth-brooding females reduced bite rates, locomotion and territorial defence compared to non-brooding adults. Feeding rates correlated positively with locomotion, as fish moving around more also spent more time with territory defence and other social interactions. This suggests that buccal feeding is costly when compared to mere incubation without feeding the young. In an experiment, in which we controlled the access of females to food, we showed that these costs are apparently not counterbalanced by a benefit to females through a shorter incubation duration. Rather, fed young were larger, heavier and had higher burst-swimming speeds. The extreme maternal investment of T. moorii appears to yield fitness benefits to females by pro-ducing larger and stronger young, which consequently should have better survival chances in their natural environment.
Article
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Although greylag geese Anser anser establish long-term monogamous pairbonds, some of the existing pairs do split up (divorce) and new pairs are formed during the annual spring mating period. In this study, male greylag geese which were involved in the challenge of an existing pairbond (challenged males and challengers) were regarded as ‘natural experimental’ groups and compared with males in stable pairbonds (unchallenged males and male-paired males, a common male strategy when the availability of females is low). In total, 37 males were investigated. The analysis included a description of the seasonal patterns of hormone levels, aggression and courtship. We tested whether hormone levels correlated with aggressive and courtship behaviours. Finally, we compared hormonal and behavioural patterns amongst the four groups. Immunoreactive testosterone (T) and corticosterone (B) equivalents were measured in faecal samples. Individual hormone levels were correlated with frequencies of agonistic male-male interactions and with frequencies of male-female courtship. During early mating and pre-laying phases, T was at its seasonal maximum, which may have masked hormone-behaviour correlations. During egg-laying, at the onset of seasonally decreased T, agonistic male-male interactions and the frequencies of courtship behaviour were significantly correlated with T. Unchallenged males had higher rates of agonistic interactions than any other males. However, unchallenged and challenged males tended to excrete T at higher levels than challengers. The high rates of being attacked and elevated levels of faecal B were indicative of the social conflict experienced by challengers. No hormonal differences were observed between heterosexually paired males and male-paired males. In summary, pairbond status and situations of social conflict had a modulating effect on T and B; however, in this study, the two hormones seem to be affected independently of one another.
Article
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We investigated the reliability of the non-invasive approach of measuring steroid hormones from feces in the domestic goose (Anser domesticus), a mainly herbivorous bird with a short gut passage time (2–3 h). Groups of eight outdoor-housed male domestic geese were subjected to three different experiments, injection of either GnRH analogue or ACTH, or ”social stimulation” by confrontation with two alien males or females. These experiments were replicated in three different seasons, in spring, during peak reproductive activity, in summer, during long-day photorefractoriness and postnuptial molt, and in fall, during sexual reactivation. GnRH stimulation resulted in significant increases of mean response and peak fecal testosterone metabolites (TM) in spring and fall. Response TM concentrations excreted in spring were generally higher than in summer and fall. Social confrontation with two females, but not with two males, increased mean and peak TM in all seasons. In general, ACTH treatment resulted in a proportionally higher increase of fecal corticosterone metabolites (BM) than GnRH did in fecal TM (80- to 140-fold vs 6- to 8-fold). ACTH significantly increased mean and peak BM in all seasons. Social confrontation with two males significantly increased fecal BM in spring, but confrontation with two females increased fecal BM in fall. Our results indicate that determining steroids from feces is a generally valid approach. However, the sensitivity of the method may vary between different hormones and results may differ between seasons. BM results seemed more sensitive and seasonally robust than did TM.
Article
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In two groups (eight individuals each) of socially acquainted, outdoor-kept, domestic ganders (male Hungarian white: Anser domesticus), basal and GnRH-stimulated plasma testosterone (T) concentrations were compared with fecal testosterone metabolites (TM) in and between three seasons, spring peak of reproductive activity, summer photorefractoriness, and fall sexual reactivation. Plasma was sampled 90 min following the challenge and T was analyzed by radioimmunoassay following the GnRH challenge. Fecal TM were measured by enzyme immunoassay using two group-specific antibodies against 17β-OH-androgens or a novel antibody against 17-oxo groups, which was found to react with major testosterone metabolites without prior hydrolytic deconjugation. Baseline plasma T and systemic levels were high in spring and fall but low in summer. Plasma T increases in response to GnRH were followed by significantly elevated fecal TM levels 2 to 6 h following the challenge in spring and fall. In fall, at high plasma T levels, fecal TM levels were disproportionally lower than in spring. Variability of TM levels was two to five times higher in feces than in plasma, which explains why correlations between individual plasma T and fecal TM levels generally remained nonsignificant. This points to a low-level short-term relationship between the excreted TM and the plasma T levels. However, the reliability of the method was demonstrated by standard inter- and intraassay variablilities and by a high correspondence between results obtained by the two assays. It is suggested that, with appropriate sample size, fecal TM reflects plasma T increase. However, fecal TM was more variable than the plasma T, and fecal TM responses to GnRH did not always parallel the plasma T response. In addition, seasonal changes in androgen excretion regimes must be taken into account.
Article
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Seasonal patterns of fecal 17β-OH-androgen, estrogen, and progesterone equivalents of male and female greylag geese (Anser anser) were analyzed in a flock of free-living geese. These were compared among social categories determined by pairbond status and breeding success. The annual cycle was divided into 13 phases. Phasewise intra-sexual comparisons were made between social categories. The seasonal variation obtained from feces was in general agreement with the literature on plasma patterns in geese and other temperate-zone birds. However, there were distinct differences in seasonal hormone patterns among the social categories. In unpaired males, androgen was elevated for a longer period of time during sexually active phases compared with paired males. In male geese, high levels of androgen did not interfere with parenting but were related to pairbond status, whereas in females, androgen and progesterone were positively related to parental behavior. In the Fall, androgen, progesterone, and estrogen peaked only in unpaired males. In unsuccessful females, estrogen started to increase earlier in the Winter and was higher in amplitude and duration than that in females guarding offspring. In general, fecal steroids showed a clear-cut difference only between sexually active and parental phases of the year in the successfully breeding pairs, whereas unpaired males retained a hormonal state closer to sexually active phases throughout the year.
Article
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Three Merino ewes, adapted for about 3 weeks to their environment, were bled at 10 min intervals through a jugular venous cannula. Radioimmunoassay of plasma samples for cortisol revealed marked diurnal variations with peak levels just after midnight and lowest values in the afternoon. This rhythm appeared to result from a changing amplitude associated with a distinct ultradian rhythm (frequency 0.8-1.2 cycles/h) in the plasma level of cortisol. Calculation of the daily rate of secretion of cortisol from the hormone profiles gave a mean value of 8.49 mg. Arguments are put forward in favour of this method for obtaining the true rate of secretion of cortisol.
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In this study we tested the hypothesis that in a passerine bird (great tit, Parus major) individuals differing for coping strategies differ in the magnitude of the adrenocortical response to social stress as well. Furthermore, we aimed at characterizing daily rhythms in corticosteroid release before and after social stress. We used 16 males from either of two lines bidirectionally selected for different coping strategies (fast and slow explorers). Social stress was induced by confrontation with an aggressive resident male. Corticosteroid metabolites were analyzed in feces collected at 90-min intervals from 900 to 1630 h on a baseline day, on the day of the social conflict, and on the following day. In both days and in both lines levels varied with time of day in a robust rhythm with a peak in the first sample of the morning and a trough at the end of the light phase. This rhythm correlates with activity (perch hopping). An overall increase in levels relative to baseline day was observed between 30 and 140 min after the challenge. Birds of the less aggressive and more cautious line (slow explorers) showed a trend for a higher response compared to birds of the more aggressive and bolder line (fast explorers), which showed almost no response. On the day after the challenge the birds of the slow line exhibited significantly reduced corticosteroid secretion, probably due to an increased negative feedback. The results provide evidence for a physiological basis of different coping strategies in birds, emerging in response to social stress and with a pattern similar to that in other vertebrates.
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Behavioral endocrinologists are aware that many hormones exhibit a diurnal rhythm, and attempt to correct for this pattern by collecting physiological samples only during specified time windows of varying lengths. In studies utilizing urinary measures of hormone levels, this window often spans 2 h or longer. In this study, we compared chimpanzee urinary cortisol levels in sample pairs collected within 1 h of each other in an attempt to validate the use of a time window for sample collection. Chimpanzees were housed at the University of Louisiana New Iberia Research Center and trained to urinate into a paper cup on command; a total of 41 sample pairs were included in this analysis. We found that mean cortisol levels in the two sets of samples, collected within 1 h or less of each other, were significantly different; the mean cortisol level of the first set of samples was significantly higher than that of the second set. This hormone's diurnal pattern of secretion accounts for this significant decrease over a very short time period. We conclude that collection methodologies involving time windows of 1 h or longer need to take into account such rapid changes in levels of excreted hormone. We advocate the use of methodological and statistical corrections to decrease the impact of short-term fluctuations in urinary cortisol.
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In many species, seasonal activities such as reproduction or migration need to be fine-tuned with weather conditions. Air pressure and temperature changes are the best parameters for such conditions. Adapting to climatic changes invariably involves physiological and behavioral reactions associated with the adrenals. In the present study, we investigated the effects of ambient temperature and air pressure on excreted immuno-reactive metabolites of corticosterone (BM) and androgens (AM). Focal individuals were 14 paired male greylag geese (Anser anser) from a semi-tame, unrestrained flock. BM and AM were measured in individual fecal samples over 25 days in November and December. Two different ACTH-validated assays were used for the assessment of BM: the first one cross-reacting with 11beta,21-diol-20-one structures ("old assay") and the second one with 5beta,3alpha,11beta-diol structures ("new assay"). With the "new assay," BM correlated negatively with the minimum ambient temperature of the night before, which may reflect corticosterone involvement in thermoregulation. BM also correlated positively with the minimum air pressure of the previous afternoon, which supports the value of air pressure for predicting weather conditions. Together, these reactions suggest a role of the adrenals in responding behaviorally and physiologically to changes in weather. Preliminary analysis indicated a higher sensitivity to the excreted glucocorticosteroid metabolites in the "new assay." As expected for outside the mating season, no relationships were found between excreted AM and the weather parameters considered. The gradual changes in BM excretion in parallel with weather conditions may be part of the fine-tuning of physiology and behavior by environmental clues.