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Alexander S Kitaysky - One of the best experts on this subject based on the ideXlab platform.
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Corticosterone mediates carry-over effects between breeding and migration in the Kittiwake Rissa tridactyla
Marine Ecology Progress Series, 2014Co-Authors: Jannick Schultner, Børge Moe, Claus Bech, Olivier Chastel, Sabrina Tartu, Alexander S KitayskyAbstract:Carry-over effects, i.e. when processes in one season influence processes in the next, are believed to have important effects on behavior and fitness in animals. Despite an increasing interest in the identification of carry-over effects, there are few experimental studies of the underlying mechanisms. We investigated how a short-term experimental elevation of the stress hormone corticosterone (CORT) during breeding influences the migratory behavior of black-legged Kittiwakes Rissa tridactyla. We exposed chick-rearing Kittiwakes to a 3 d elevation of CORT, which is usually secreted in response to food shortages. The migratory behavior of CORT-treated Kittiwakes and a control group was then tracked using geolocators. We found that CORT treatment affected subsequent autumn migration in a sex-specific manner. CORT-treated females left the breeding grounds earlier and spent a longer period at the wintering grounds than control birds and CORT-treated males. The CORT treatment did not affect the timing of spring arrival or total length of migration. Our findings indicated that physiological stress incurred during breeding can carry over to affect key parameters of migratory behavior in autumn. Identifying carry-over mechanisms, such as those described here, is important to understand how performance and fitness in animals are determined by interactions between different parts of their life cycle.
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differential reproductive responses to stress reveal the role of life history strategies within a species
Proceedings of The Royal Society B: Biological Sciences, 2013Co-Authors: Jannik Schultner, Alexander S Kitaysky, Scott A Hatch, Geir W. Gabrielsen, Claus BechAbstract:Life-history strategies describe that ‘slow’- in contrast to ‘fast’-living species allocate resources cautiously towards reproduction to enhance survival. Recent evidence suggests that variation in strategies exists not only among species but also among populations of the same species. Here, we examined the effect of experimentally induced stress on resource allocation of breeding seabirds in two populations with contrasting life-history strategies: slow-living Pacific and fast-living Atlantic black-legged Kittiwakes. We tested the hypothesis that reproductive responses in Kittiwakes under stress reflect their life-history strategies. We predicted that in response to stress, Pacific Kittiwakes reduce investment in reproduction compared with Atlantic Kittiwakes. We exposed chick-rearing Kittiwakes to a short-term (3-day) period of increased exogenous corticosterone (CORT), a hormone that is released during food shortages. We examined changes in baseline CORT levels, parental care and effects on offspring. We found that Kittiwakes from the two populations invested differently in offspring when facing stress. In response to elevated CORT, Pacific Kittiwakes reduced nest attendance and deserted offspring more readily than Atlantic Kittiwakes. We observed lower chick growth, a higher stress response in offspring and lower reproductive success in response to CORT implantation in Pacific Kittiwakes, whereas the opposite occurred in the Atlantic. Our findings support the hypothesis that life-history strategies predict short-term responses of individuals to stress within a species. We conclude that behaviour and physiology under stress are consistent with trade-off priorities as predicted by life-history theory. We encourage future studies to consider the pivotal role of life-history strategies when interpreting inter-population differences of animal responses to stressful environmental events.
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food availability and population processes severity of nutritional stress during reproduction predicts survival of long lived seabirds
Functional Ecology, 2010Co-Authors: Alexander S Kitaysky, Scott A Hatch, John F Piatt, Evgenia V Kitaiskaia, Michael T Shultz, Morgan Z Benowitzfredericks, John C WingfieldAbstract:Summary 1. Life-history theory predicts a trade-off between costs of current reproduction and future survival of individuals. Studies of short-lived animals in general support this prediction. However, the effect of nutritional stress during reproduction on survival of long-lived animals is poorly understood. 2. We examined the link between nutritional stress, fecundity and return to a breeding colony (hereafter ‘survival’) of black-legged Kittiwakes (Rissa tridactyla) at two colonies with contrasting patterns in adult survival, fecundity, and numerical trends. 3. We tested the observational (at Duck and Gull Is., Cook Inlet, Northern Gulf of Alaska) and experimental (at Middleton I., Gulf of Alaska) relationships between variations in the secretion of the stress hormone corticosterone (CORT) and food abundance. Then, we examined the relationships between nutritional stress (as reflected in CORT), reproduction, and survival of individuals. 4. On average, CORT was higher in Kittiwakes breeding on Duck I. (declining, low fecundity, high survival) compared to those breeding on Gull I. (increasing, high fecundity, low survival). 5. At both colonies, CORT was directly negatively correlated with food abundance quantified at sea. Experimental feeding of individuals ad libitum resulted in a reduction of CORT in birds breeding on Middleton I. These results suggest that CORT is a reliable measure of food availability and defines nutritional stress (stress) in Kittiwakes. 6. On Gull I., where survival is low (86%), production of young declined as stress increased. On Duck I., where survival is high (93%), parents always failed in raising young, though they experienced a wide range of stress levels. 7. Survival of individuals is linked to their CORT levels during reproduction. High levels of CORT predicted disappearance of individuals from both colonies. 8. The results support the hypothesis that nutritional stress during reproduction affects both survival and reproduction in long-lived animals. However, even within a species the ways in which survival and reproduction trade-off against each other may vary among populations. Results suggest that reproductive consequences of nutritional stress might differ between declining and increasing populations, which should be tested. We conclude that severity of nutritional stress during reproduction is one of the major factors defining population processes in Kittiwakes.
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unifying quantitative life history theory and field endocrinology to assess prudent parenthood in a long lived seabird
Evolutionary Ecology Research, 2010Co-Authors: William H Satterthwaite, Alexander S Kitaysky, Scott A Hatch, John F Piatt, Marc MangelAbstract:Question: Can field measurements of stress hormones help us to assess the prudent parent hypothesis in a long-lived seabird? Organism: Black-legged Kittiwake, Rissa tridactyla. Location: Duck and Gull Islands, Cook Inlet, Alaska, USA. Methods: We examined the statistical relationship between the stress hormone corticosterone and mortality in black-legged Kittiwakes. We built a demographic model of the Kittiwake life cycle to determine whether the mortality rates associated with persisting in a breeding attempt despite high corticosterone caused the birds to sacrifice more lifetime reproductive output than they gain from one year’s breeding. Results: The probability of apparent mortality increased with corticosterone, suggesting some birds incurred increased mortality risk for the sake of breeding. For Duck Island (low reproductive success), it appears birds sacrificed more lifetime reproductive success than a prudent parent would. On Gull Island, it appears most but possibly not all birds were behaving in ways consistent with theory, although definitive statements require larger samples of highly stressed birds.
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a mechanistic link between chick diet and decline in seabirds
Proceedings of The Royal Society B: Biological Sciences, 2006Co-Authors: Alexander S Kitaysky, John F Piatt, Evgenia V Kitaiskaia, John C WingfieldAbstract:A climatic regime shift during the mid-1970s in the North Pacific resulted in decreased availability of lipid-rich fish to seabirds and was followed by a dramatic decline in number of Kittiwakes breeding on the Pribilof Islands. Although production of chicks in the mid-1970s was adequate to sustain Kittiwake populations in the early 1980s, the disappearance of birds from breeding colonies apparently exceeded recruitment. No mechanism has been proposed to explain why recruitment would differ among fledglings fed lipid-rich or lipid-poor fish during development. Here we show that diets low in lipids induce nutritional stress and impair cognitive abilities in young red-legged Kittiwakes, Rissa brevirostris. Specifically, growth retardation, increased secretion of stress hormones and inferior ability to associate food distribution with visual cues were observed in individuals fed lipid-poor diets. We conclude that lipid-poor diets during development affect the quality of young seabirds, which is likely to result in their increased mortality and low recruitment.
J C Coulson - One of the best experts on this subject based on the ideXlab platform.
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egg size and shape in the Kittiwake rissa tridactyla and their use in estimating age composition of populations
Journal of Zoology, 2009Co-Authors: J C CoulsonAbstract:The size and shape of Kittiwake eggs are influenced by several factors, in particular by the position of the egg in the laying sequence, the breeding experience of the female and a possible inherited effect which tends to make the same female lay similar eggs in successive years. The adult Kittiwake becomes larger towards the north of its range (Bergman's Rule) and probably as a consequence of this, the eggs also tend to be larger towards the north. In general, as female Kittiwakes become older, their eggs become shorter and broader while the shape index (breadth × 100/length) and volume also tend to increase. These changes become less marked as the birds become older but there is no indication of the breadth and egg volume becoming smaller in older birds although very few birds over eight years of breeding age were studied. It is shown that several Laridae laying clutches of three eggs lay a final egg which differs markedly from the first two in both shape and size. In the Kittiwake, this difference (as nieasured by the variance) increases with age but no such difference occurs in clutches of two eggs. The use of the egg characteristics as a means of determining the age composition of breeding females in populations or colonies is discussed and applied to two colonies of Kittiwakes where the age composition was unknown. It is suggested that, according to the species and the clutch size, the shape index and the variance of the breadth within a clutch are probably the most useful characters for such a method.
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reproductive success of the Kittiwake rissa tridactyla the roles of clutch size chick growth rates and parental quality
Ibis, 2008Co-Authors: J C Coulson, J M PorterAbstract:Kittiwake growth rates and breeding success are examined in relation to survival between fledging and breeding and to adult survival rates. High chick growth rates lead to increased survival after fledging. Broods of three (the maximum brood size) did not suffer lower fledging success than broods of two and clutches of three fledged appreciably more chicks per pair than did clutches of two or one. On average, the a- and b-chicks in broods of three grew at a faster rate and had a higher survival before breeding than those from smaller broods. Chicks from broods of two with experienced female parents grew at a faster rate than those of inexperienced female parents. Female parents which laid three egg clutches had a higher survival rate than those which laid clutches of two or one. We contend that three egg clutches were laid by higher quality individuals. We believe that clutch size indicates the condition of the Kittiwakes forming the pair. This condition probably has a genetical component, but is modified by environmental factors.
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a study of colonies of the Kittiwake rissa tridactyla l
Ibis, 2008Co-Authors: J C Coulson, E WhiteAbstract:Summary. 1 The history of Kittiwake colonics at Marsden, Co. Durham and North Shields, Northumberland is given. Since the original colonization of the area in 1930, nine colonies have been formed which, in 1954, ranged in size from 13 to 648 nests. 2 New colonies were formed by birds being present on the site a year before breeding commenced. Immigration continued for at least the first four years of a colony's existence. Colour-ringing showed that adult Kittiwakes exhibited both colony-and site-tenacity. 3 A large proportion of non-breeding birds was present, higher in the younger colonies. These birds returned to the colonies later than the breeding birds and the majority were young birds returning for the first time. In 1953 at least 19% of the population in the area were non-breeding birds. 4 Colony age and colony size were closely correlated. The return to the colonies and onset of breeding within the colonies occurred first in the oldest and last in the youngest colonies. 5 Birds of the same age bred at the same time irrespective of colony size. Furhter, the spread of breeding within large colonies was greater than in small ones, whereas the reverse would have been expected if “social stimulation” was of major importance. 6 It is conducted that the age of birds within a colony is more important than “social stimulation” in influencing the time of breeding.
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the effect of age on the breeding biology of the kitttwake rissa tridactyla
Ibis, 2008Co-Authors: J C Coulson, E WhiteAbstract:Summary 1. From 1954 to 1956 inclusive, the biology of individual marked Kittiwakes was studied at North Shields, Northumberland. 2. It was concluded that older Kittiwakes reacted to the breeding stimulus earlier, more intensively and with greater success than younger breeding birds. 3. Birds with previous breeding experience returned to the colony before birds breeding for the first time and these before non-breeders. 4. Before breeding started, birds which had bred previously spent more of their time at the colony than those about to breed for the first time. 5. Birds breeding for at least the second time laid the first egg 7·5 days earlier than those breeding for the first time. 6. Breeding started one day later for every four days the return to the colony was postponed. 7. Older breeding birds showed greater nest-site tenacity, laid larger clutches and had greater breeding success than younger birds. 8. The chicks in broods of two (but not of one) increased in weight more rapidly where the parents had previous experience. 9. Breeding Kittiwakes showed strong colony tenacity, but 24% of the marked non-breeding birds were subsequently seen in other colonies. 10. Over half the birds retained the same mate as in the previous year.
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the annual re occupation of breeding sites by the fulmar
Ibis, 2008Co-Authors: J C Coulson, Jean M HorobinAbstract:Summary The Fulmar has a long period at the breeding colony prior to egg-laying. The pattern of annual occupation and build-up in numbers has been examined in detail at Marsden, Co. Durham, at a colony in which over 100 eggs are laid annually (Order 3 of Fisher's classification). The re-occupation of the cliff starts in early November with an occasional visit by one or two birds. The main period of activity at the cliff is during the morning and, as the numbers build up, the diurnal period of occupation increases. By mid-December the first birds to arrive in the colony do so before dawn and the last to leave remain well after dark until near midnight. Almost throughout the pre-egg stage, the colony is deserted each night and re-occupied the next day and birds only stay regularly overnight just before egg-laying. A similar pattern of occupation occurs after breeding but in the reverse order. The numbers of birds at the colony in January and February exceed the breeding population and include many non-breeders. The non-breeders progressively decline in numbers until May when only the breeding birds remain with a few non-breeding birds. The daily variation in the numbers of birds at the cliff is influenced by the wind speed. In general, the birds leave the colony under freshening conditions and the number present at the colony can be interpreted in terms of the wind conditions over the last three days. It is suggested that the synchronised departures are primarily feeding trips, the birds using the strong winds to reach feeding areas, except that the departure just before egg-laying is linked to egg development and synchronised laying in the colony. Competition between Fulmars and Kittiwakes for nesting sites usually results in the Kittiwakes gaining the site. This is achieved by the Kittiwakes taking over the Fulmar sites during one of the latter's departures.
Scott A Hatch - One of the best experts on this subject based on the ideXlab platform.
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windscapes shape seabird instantaneous energy costs but adult behavior buffers impact on offspring
Movement ecology, 2014Co-Authors: Kyle H Elliott, Scott A Hatch, Anthony J. Gaston, Lorraine S Chivers, Lauren Bessey, Akiko Kato, Orla Osborne, Yan RopertcoudertAbstract:Windscapes affect energy costs for flying animals, but animals can adjust their behavior to accommodate wind-induced energy costs. Theory predicts that flying animals should decrease air speed to compensate for increased tailwind speed and increase air speed to compensate for increased crosswind speed. In addition, animals are expected to vary their foraging effort in time and space to maximize energy efficiency across variable windscapes. We examined the influence of wind on seabird (thick-billed murre Uria lomvia and black-legged Kittiwake Rissa tridactyla) foraging behavior. Airspeed and mechanical flight costs (dynamic body acceleration and wing beat frequency) increased with headwind speed during commuting flights. As predicted, birds adjusted their airspeed to compensate for crosswinds and to reduce the effect of a headwind, but they could not completely compensate for the latter. As we were able to account for the effect of sampling frequency and wind speed, we accurately estimated commuting flight speed with no wind as 16.6 ms−1 (murres) and 10.6 ms−1 (Kittiwakes). High winds decreased delivery rates of schooling fish (murres), energy (murres) and food (Kittiwakes) but did not impact daily energy expenditure or chick growth rates. During high winds, murres switched from feeding their offspring with schooling fish, which required substantial above-water searching, to amphipods, which required less above-water searching. Adults buffered the adverse effect of high winds on chick growth rates by switching to other food sources during windy days or increasing food delivery rates when weather improved.
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differential reproductive responses to stress reveal the role of life history strategies within a species
Proceedings of The Royal Society B: Biological Sciences, 2013Co-Authors: Jannik Schultner, Alexander S Kitaysky, Scott A Hatch, Geir W. Gabrielsen, Claus BechAbstract:Life-history strategies describe that ‘slow’- in contrast to ‘fast’-living species allocate resources cautiously towards reproduction to enhance survival. Recent evidence suggests that variation in strategies exists not only among species but also among populations of the same species. Here, we examined the effect of experimentally induced stress on resource allocation of breeding seabirds in two populations with contrasting life-history strategies: slow-living Pacific and fast-living Atlantic black-legged Kittiwakes. We tested the hypothesis that reproductive responses in Kittiwakes under stress reflect their life-history strategies. We predicted that in response to stress, Pacific Kittiwakes reduce investment in reproduction compared with Atlantic Kittiwakes. We exposed chick-rearing Kittiwakes to a short-term (3-day) period of increased exogenous corticosterone (CORT), a hormone that is released during food shortages. We examined changes in baseline CORT levels, parental care and effects on offspring. We found that Kittiwakes from the two populations invested differently in offspring when facing stress. In response to elevated CORT, Pacific Kittiwakes reduced nest attendance and deserted offspring more readily than Atlantic Kittiwakes. We observed lower chick growth, a higher stress response in offspring and lower reproductive success in response to CORT implantation in Pacific Kittiwakes, whereas the opposite occurred in the Atlantic. Our findings support the hypothesis that life-history strategies predict short-term responses of individuals to stress within a species. We conclude that behaviour and physiology under stress are consistent with trade-off priorities as predicted by life-history theory. We encourage future studies to consider the pivotal role of life-history strategies when interpreting inter-population differences of animal responses to stressful environmental events.
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thyroid hormones correlate with resting metabolic rate not daily energy expenditure in two charadriiform seabirds
Biology Open, 2013Co-Authors: Kyle H Elliott, Scott A Hatch, Anthony J. Gaston, Jorg Welcker, Vince P Palace, James F Hare, John R Speakman, Gary W AndersonAbstract:Thyroid hormones affect in vitro metabolic intensity, increase basal metabolic rate (BMR) in the lab, and are sometimes correlated with basal and/or resting metabolic rate (RMR) in a field environment. Given the difficulty of measuring metabolic rate in the field—and the likelihood that capture and long-term restraint necessary to measure metabolic rate in the field jeopardizes other measurements—we examined the possibility that circulating thyroid hormone levels were correlated with RMR in two free-ranging bird species with high levels of energy expenditure (the black-legged Kittiwake, Rissa tridactyla, and thick-billed murre, Uria lomvia). Because BMR and daily energy expenditure (DEE) are purported to be linked, we also tested for a correlation between thyroid hormones and DEE. We examined the relationships between free and bound levels of the thyroid hormones thyroxine (T4) and triiodothyronine (T3) with DEE and with 4-hour long measurements of post-absorptive and thermoneutral resting metabolism (resting metabolic rate; RMR). RMR but not DEE increased with T3 in both species; both metabolic rates were independent of T4. T3 and T4 were not correlated with one another. DEE correlated with body mass in Kittiwakes but not in murres, presumably owing to the larger coefficient of variation in body mass during chick rearing for the more sexually dimorphic Kittiwakes. We suggest T3 provides a good proxy for resting metabolism but not DEE in these seabird species.
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age related differences in the cloacal microbiota of a wild bird species
BMC Ecology, 2013Co-Authors: Wouter F D Van Dongen, Sarah Leclaire, Pierrick Blanchard, Joël White, Etienne Danchin, Hanja B Brandl, Yoshan Moodley, Thomas Merkling, Scott A HatchAbstract:Gastrointestinal bacteria play a central role in the health of animals. The bacteria that individuals acquire as they age may therefore have profound consequences for their future fitness. However, changes in microbial community structure with host age remain poorly understood. We characterised the cloacal bacteria assemblages of chicks and adults in a natural population of black-legged Kittiwakes (Rissa tridactyla), using molecular methods. We show that the Kittiwake cloaca hosts a diverse assemblage of bacteria. A greater number of total bacterial OTUs (operational taxonomic units) were identified in chicks than adults, and chicks appeared to host a greater number of OTUs that were only isolated from single individuals. In contrast, the number of bacteria identified per individual was higher in adults than chicks, while older chicks hosted more OTUs than younger chicks. Finally, chicks and adults shared only seven OTUs, resulting in pronounced differences in microbial assemblages. This result is surprising given that adults regurgitate food to chicks and share the same nesting environment. Our findings suggest that chick gastrointestinal tracts are colonised by many transient species and that bacterial assemblages gradually transition to a more stable adult state. Phenotypic differences between chicks and adults may lead to these strong differences in bacterial communities. These data provide the framework for future studies targeting the causes and consequences of variation in bacterial assemblages in wild birds.
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Symmetry of black wingtipS iS related to clutch Size and integument coloration in black-legged KittiwakeS (RISSA TRIDACTYLA)
The Auk, 2013Co-Authors: Sarah Leclaire, Scott A Hatch, Pierrick Blanchard, Joël White, Etienne DanchinAbstract:ABSTRACT. Fluctuating asymmetry has been suggested to be a phenotypic marker of developmental stability and is often seen as an indicator of overall quality. However, its role in sexual selection has been debated. To determine the potential role of black wingtip asymmetry in sexual selection in Black-legged Kittiwakes (Rissa tridactyla), we investigated whether symmetry was correlated with reproductive success and integument coloration, a trait probably sexually selected in this species. We found that, in males, asymmetry was associated with low clutch size and brood size but was independent of fledging success, which suggests that wingtip symmetry may reflect fertility in males. Asymmetry of black wingtip was also associated with duller integument, which emphasizes the potential importance of integument color in indicating individual quality. Further studies are needed to determine whether Black-legged Kittiwakes can discriminate between asymmetric and symmetric birds and use it as a cue in mate choice o...
Børge Moe - One of the best experts on this subject based on the ideXlab platform.
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Dataset for: Organochlorines, perfluoroalkyl substances, mercury and egg incubation temperature in an Arctic seabird: insight from data loggers
2018Co-Authors: Pierre Blévin, Børge Moe, Geir Wing Gabrielsen, Scott Shaffer, Paco Bustamante, Frédéric Angelier, Baptiste Picard, Dorte Herzke, Jan Ove Bustnes, Olivier ChastelAbstract:In birds, incubation-related behaviors and brood patch formation are influenced by hormonal regulation like prolactin secretion. Brood patch provides efficient heat transfer between the incubating parent and the developing embryo in the egg. Importantly, several environmental contaminants are already known to have adverse effects on avian reproduction. However, relatively little is known about the effect of contaminants on incubation temperature (Tinc) for wild birds. By using temperature thermistors placed into artificial eggs, we investigated whether the most contaminated parent birds are less able to provide appropriate egg warming and thus less committed in incubating their clutch. Specifically, we investigated the relationships between three groups of contaminants (organochlorines (OCs), perfluoroalkyl substances (PFASs), and mercury (Hg)) with Tinc and also with prolactin concentrations and brood patch size in incubating Arctic black-legged Kittiwakes (Rissa tridactyla). Our results reveal that among the considered OCs, only blood levels of oxychlordane, the main metabolite of “chlordane”, a banned pesticide, were negatively related to the minimum incubation temperature in male Kittiwakes. PFAS and Hg levels were unrelated to Tinc in Kittiwakes. Moreover, our study suggests a possible underlying mechanism since we reported a significant and negative association between blood oxychlordane concentrations and the size of the brood patch in males. Finally, this reduced Tinc in the most oxychlordane-contaminated Kittiwakes was associated with a lower egg hatching probability
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Testosterone increases siblicidal aggression in black-legged Kittiwake chicks (Rissa tridactyla)
Behavioral Ecology and Sociobiology, 2014Co-Authors: Martina S. Müller, Børge Moe, Ton G. G. GroothuisAbstract:To compete for parental food deliveries nestling birds have evolved diverse behaviors such as begging displays and sibling aggression. Testosterone has been suggested to be an important mechanism orchestrating such competitive behaviors, but evidence is scarce and often indirect. Siblicidal species provide an interesting case in which a clear dominance hierarchy is established and the dominant chicks lethally attack siblings. We experimentally elevated testosterone in chicks of a facultatively siblicidal species, the black-legged Kittiwake, Rissa tridactyla , and showed that testosterone-treated chicks were more aggressive toward their sibling than were control chicks. In such facultatively siblicidal species, chicks normally exhibit intense aggression only when threatened by starvation. Indeed, we found that chicks in relatively poorer condition were more aggressive than were chicks in better condition, even among testosterone-treated chicks, suggesting the action of an additional signal modulating aggression. Relatively larger siblings were also more aggressive than were relatively smaller siblings, confirming the importance of size advantage in determining dominance hierarchies within the brood. In addition, testosterone increased aggression toward a simulated predator, indicating that in Kittiwakes testosterone can increase aggression in contexts other than siblicide. Testosterone promoted aggression-mediated dominance, which increased begging although testosterone treatment did not have a significant separate effect on begging. Therefore, testosterone production in the Kittiwake and most likely other siblicidal species seems an important fitness mediator already early in life, outside the sexual context and not only manifesting itself in aggressive behavior but also in dominance-mediated effects on food solicitation displays toward parents.
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Corticosterone mediates carry-over effects between breeding and migration in the Kittiwake Rissa tridactyla
Marine Ecology Progress Series, 2014Co-Authors: Jannick Schultner, Børge Moe, Claus Bech, Olivier Chastel, Sabrina Tartu, Alexander S KitayskyAbstract:Carry-over effects, i.e. when processes in one season influence processes in the next, are believed to have important effects on behavior and fitness in animals. Despite an increasing interest in the identification of carry-over effects, there are few experimental studies of the underlying mechanisms. We investigated how a short-term experimental elevation of the stress hormone corticosterone (CORT) during breeding influences the migratory behavior of black-legged Kittiwakes Rissa tridactyla. We exposed chick-rearing Kittiwakes to a 3 d elevation of CORT, which is usually secreted in response to food shortages. The migratory behavior of CORT-treated Kittiwakes and a control group was then tracked using geolocators. We found that CORT treatment affected subsequent autumn migration in a sex-specific manner. CORT-treated females left the breeding grounds earlier and spent a longer period at the wintering grounds than control birds and CORT-treated males. The CORT treatment did not affect the timing of spring arrival or total length of migration. Our findings indicated that physiological stress incurred during breeding can carry over to affect key parameters of migratory behavior in autumn. Identifying carry-over mechanisms, such as those described here, is important to understand how performance and fitness in animals are determined by interactions between different parts of their life cycle.
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multicolony tracking reveals the winter distribution of a pelagic seabird on an ocean basin scale
Diversity and Distributions, 2012Co-Authors: Morten Frederiksen, Børge Moe, Thierry Boulinier, John W. Chardine, Robert T Barrett, Francis Daunt, Richard A Phillips, Maria I Bogdanova, Olivier Chastel, Lorraine S ChiversAbstract:Aim: An understanding of the non-breeding distribution and ecology of migratory species is necessary for successful conservation. Many seabirds spend the non-breeding season far from land, and information on their distribution during this time is very limited. The black-legged Kittiwake, Rissa tridactyla, is a widespread and numerous seabird in the North Atlantic and Pacific, but breeding populations throughout the Atlantic range have declined recently. To help understand the reasons for the declines, we tracked adults from colonies throughout the Atlantic range over the non-breeding season using light-based geolocation. Location: North Atlantic. Methods: Geolocation data loggers were deployed on breeding Kittiwakes from 19 colonies in 2008 and 2009 and retrieved in 2009 and 2010. Data from 236 loggers were processed and plotted using GIS. Size and composition of wintering populations were estimated using information on breeding population size. Results: Most tracked birds spent the winter in the West Atlantic, between Newfoundland and the Mid-Atlantic Ridge, including in offshore, deep-water areas. Some birds (mainly local breeders) wintered in the North Sea and west of the British Isles. There was a large overlap in winter distributions of birds from different colonies, and colonies closer to each other showed larger overlap. We estimated that 80% of the 4.5 million adult Kittiwakes in the Atlantic wintered west of the Mid-Atlantic Ridge, with only birds from Ireland and western Britain staying mainly on the European side. Main conclusions: The high degree of mixing in winter of Kittiwakes breeding in various parts of the Atlantic range implies that the overall population could be sensitive to potentially deteriorating environmental conditions in the West Atlantic, e.g. owing to lack of food or pollution. Our approach to estimating the size and composition of wintering populations should contribute to improved management of birds faced with such challenges.
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individual variation in field metabolic rate of Kittiwakes rissa tridactyla during the chick rearing period
Physiological and Biochemical Zoology, 2001Co-Authors: Marianne Fyhn, Geir W. Gabrielsen, Erling S. Nordøy, Børge Moe, Ingveig Langseth, Claus BechAbstract:Abstract Field metabolic rate (FMR), using the doubly labelled water (DLW) method, was measured in free‐ranging adult Kittiwakes (Rissa tridactyla) early and late in the chick‐rearing period at Svalbard, Norway. Individual variation in FMR was analysed by comparing FMR with body mass, sex, nest attendance, chick age, brood size, and basal metabolic rate (BMR). Mean FMR of Kittiwakes during the chick‐rearing period was \documentclass{aastex} \usepackage{amsbsy} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{bm} \usepackage{mathrsfs} \usepackage{pifont} \usepackage{stmaryrd} \usepackage{textcomp} \usepackage{portland,xspace} \usepackage{amsmath,amsxtra} \usepackage[OT2,OT1]{fontenc} \newcommand\cyr{ \renewcommand\rmdefault{wncyr} \renewcommand\sfdefault{wncyss} \renewcommand\encodingdefault{OT2} \normalfont \selectfont} \DeclareTextFontCommand{\textcyr}{\cyr} \pagestyle{empty} \DeclareMathSizes{10}{9}{7}{6} \begin{document} \landscape $27.0\pm 0.9$ \end{document} (SE) W kg−1, while the individual va...
John F Piatt - One of the best experts on this subject based on the ideXlab platform.
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regionalizing indicators for marine ecosystems bering sea aleutian island seabirds climate and competitors
Ecological Indicators, 2017Co-Authors: William J Sydeman, John F Piatt, Sarah Ann Thompson, Marisol Garciareyes, Stephani G Zador, Jeffrey C Williams, Marc D Romano, Heather M RennerAbstract:Abstract Seabirds are thought to be reliable, real-time indicators of forage fish availability and the climatic and biotic factors affecting pelagic food webs in marine ecosystems. In this study, we tested the hypothesis that temporal trends and interannual variability in seabird indicators reflect simultaneously occurring bottom-up (climatic) and competitor (pink salmon) forcing of food webs. To test this hypothesis, we derived multivariate seabird indicators for the Bering Sea–Aleutian Island (BSAI) ecosystem and related them to physical and biological conditions known to affect pelagic food webs in the ecosystem. We examined covariance in the breeding biology of congeneric pelagic gulls (Kittiwakes Rissa tridactyla and R. brevirostris ) and auks (murres Uria aalge and U. lomvia ), all of which are abundant and well-studied in the BSAI. At the large ecosystem scale, Kittiwake and murre breeding success and phenology (hatch dates) covaried among congeners, so data could be combined using multivariate techniques, but patterns of response differed substantially between the genera. While data from all sites ( n = 5) in the ecosystem could be combined, the south eastern Bering Sea shelf colonies (St. George, St. Paul, and Cape Peirce) provided the strongest loadings on indicators, and hence had the strongest influence on modes of variability. The Kittiwake breeding success mode of variability, dominated by biennial variation, was significantly related to both climatic factors and potential competitor interactions. The murre indicator mode was interannual and only weakly related to the climatic factors measured. The Kittiwake phenology indicator mode of variability showed multi-year periods (“stanzas”) of late or early breeding, while the murre phenology indicator showed a trend towards earlier timing. Ocean climate relationships with the Kittiwake breeding success indicator suggest that early-season (winter–spring) environmental conditions and the abundance of pink salmon affect the pelagic food webs that support these seabirds in the BSAI ecosystem.
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food availability and population processes severity of nutritional stress during reproduction predicts survival of long lived seabirds
Functional Ecology, 2010Co-Authors: Alexander S Kitaysky, Scott A Hatch, John F Piatt, Evgenia V Kitaiskaia, Michael T Shultz, Morgan Z Benowitzfredericks, John C WingfieldAbstract:Summary 1. Life-history theory predicts a trade-off between costs of current reproduction and future survival of individuals. Studies of short-lived animals in general support this prediction. However, the effect of nutritional stress during reproduction on survival of long-lived animals is poorly understood. 2. We examined the link between nutritional stress, fecundity and return to a breeding colony (hereafter ‘survival’) of black-legged Kittiwakes (Rissa tridactyla) at two colonies with contrasting patterns in adult survival, fecundity, and numerical trends. 3. We tested the observational (at Duck and Gull Is., Cook Inlet, Northern Gulf of Alaska) and experimental (at Middleton I., Gulf of Alaska) relationships between variations in the secretion of the stress hormone corticosterone (CORT) and food abundance. Then, we examined the relationships between nutritional stress (as reflected in CORT), reproduction, and survival of individuals. 4. On average, CORT was higher in Kittiwakes breeding on Duck I. (declining, low fecundity, high survival) compared to those breeding on Gull I. (increasing, high fecundity, low survival). 5. At both colonies, CORT was directly negatively correlated with food abundance quantified at sea. Experimental feeding of individuals ad libitum resulted in a reduction of CORT in birds breeding on Middleton I. These results suggest that CORT is a reliable measure of food availability and defines nutritional stress (stress) in Kittiwakes. 6. On Gull I., where survival is low (86%), production of young declined as stress increased. On Duck I., where survival is high (93%), parents always failed in raising young, though they experienced a wide range of stress levels. 7. Survival of individuals is linked to their CORT levels during reproduction. High levels of CORT predicted disappearance of individuals from both colonies. 8. The results support the hypothesis that nutritional stress during reproduction affects both survival and reproduction in long-lived animals. However, even within a species the ways in which survival and reproduction trade-off against each other may vary among populations. Results suggest that reproductive consequences of nutritional stress might differ between declining and increasing populations, which should be tested. We conclude that severity of nutritional stress during reproduction is one of the major factors defining population processes in Kittiwakes.
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unifying quantitative life history theory and field endocrinology to assess prudent parenthood in a long lived seabird
Evolutionary Ecology Research, 2010Co-Authors: William H Satterthwaite, Alexander S Kitaysky, Scott A Hatch, John F Piatt, Marc MangelAbstract:Question: Can field measurements of stress hormones help us to assess the prudent parent hypothesis in a long-lived seabird? Organism: Black-legged Kittiwake, Rissa tridactyla. Location: Duck and Gull Islands, Cook Inlet, Alaska, USA. Methods: We examined the statistical relationship between the stress hormone corticosterone and mortality in black-legged Kittiwakes. We built a demographic model of the Kittiwake life cycle to determine whether the mortality rates associated with persisting in a breeding attempt despite high corticosterone caused the birds to sacrifice more lifetime reproductive output than they gain from one year’s breeding. Results: The probability of apparent mortality increased with corticosterone, suggesting some birds incurred increased mortality risk for the sake of breeding. For Duck Island (low reproductive success), it appears birds sacrificed more lifetime reproductive success than a prudent parent would. On Gull Island, it appears most but possibly not all birds were behaving in ways consistent with theory, although definitive statements require larger samples of highly stressed birds.
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seabirds as indicators of marine food supplies cairns revisited
Marine Ecology Progress Series, 2007Co-Authors: John F Piatt, Ann M. A. Harding, Michael T Shultz, Suzann G Speckman, Thomas I Van Pelt, Gary S Drew, Arthur B KettleAbstract:In his seminal paper about using seabirds as indicators of marine food supplies, Cairns (1987, Biol Oceanogr 5:261-271) predicted that (1) parameters of seabird biology and behavior would vary in curvilinear fashion with changes in food supply, (2) the threshold of prey density over which birds responded would be different for each parameter, and (3) different seabird species would respond differently to variation in food availability depending on foraging behavior and ability to adjust time budgets. We tested these predictions using data collected at colonies of common murre Uria aalge and black-legged Kittiwake Rissa tridactyla in Cook Inlet, Alaska. (1) Of 22 seabird responses fitted with linear and non-linear functions, 16 responses exhibited significant curvilinear shapes, and Akaike's information criterion (AIC) analysis indicated that curvilinear functions pro- vided the best-fitting model for 12 of those. (2) However, there were few differences among para- meters in their threshold to prey density, presumably because most responses ultimately depend upon a single threshold for prey acquisition at sea. (3) There were similarities and some differences in how species responded to variability in prey density. Both murres and Kittiwakes minimized vari- ability (CV < 15%) in their own body condition and growth of chicks in the face of high annual vari- ability (CV = 69%) in local prey density. Whereas Kittiwake breeding success (CV = 63%, r 2 = 0.89) reflected prey variability, murre breeding success did not (CV = 29%, r 2 < 0.00). It appears that mur- res were able to buffer breeding success by reallocating discretionary 'loafing' time to foraging effort in response (r 2 = 0.64) to declining prey density. Kittiwakes had little or no discretionary time, so fledging success was a more direct function of local prey density. Implications of these results for using 'seabirds as indicators' are discussed.
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a mechanistic link between chick diet and decline in seabirds
Proceedings of The Royal Society B: Biological Sciences, 2006Co-Authors: Alexander S Kitaysky, John F Piatt, Evgenia V Kitaiskaia, John C WingfieldAbstract:A climatic regime shift during the mid-1970s in the North Pacific resulted in decreased availability of lipid-rich fish to seabirds and was followed by a dramatic decline in number of Kittiwakes breeding on the Pribilof Islands. Although production of chicks in the mid-1970s was adequate to sustain Kittiwake populations in the early 1980s, the disappearance of birds from breeding colonies apparently exceeded recruitment. No mechanism has been proposed to explain why recruitment would differ among fledglings fed lipid-rich or lipid-poor fish during development. Here we show that diets low in lipids induce nutritional stress and impair cognitive abilities in young red-legged Kittiwakes, Rissa brevirostris. Specifically, growth retardation, increased secretion of stress hormones and inferior ability to associate food distribution with visual cues were observed in individuals fed lipid-poor diets. We conclude that lipid-poor diets during development affect the quality of young seabirds, which is likely to result in their increased mortality and low recruitment.
