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Grounding of thousands of newly fledged petrels and shearwaters (family Procellariidae) in built‐up areas due to artificial light is a global problem. Due to their anatomy these grounded birds find it difficult to take off from built‐up areas and many fall victim to predation, cars, dehydration or starvation. This research investigated a combination of several factors that may influence the number of Manx Shearwater Puffinus puffinus groundings in a coastal village of Scotland located close to a nesting site for this species. A model was developed that used meteorological variables and moon cycle to predict the daily quantity of birds that were recovered on the ground. The model, explaining 46.32% of the variance of the data, revealed how new moon and strong onshore winds influence grounding. To a lesser extent, visibility conditions can also have an effect on grounding probabilities. The analysis presented in this study can improve rescue campaigns of not only Manx Shearwaters but also other species attracted to the light pollution by predicting conditions leading to an increase in the number of groundings. It could also inform local authorities when artificial light intensity needs to be reduced. [ABSTRACT FROM AUTHOR]

We assessed differences in diet composition between Imperial Cormorants ( Phalacrocorax atriceps) breeding at Isla Arce and Isla Vernaci Este, Golfo San Jorge, Argentina. Both colonies are located within the Patagonia Austral marine park, and commercial trawl fisheries operate in adjacent waters, thus knowledge of their food requirement is fundamental to assess potential conflicts and monitor interactions. We obtained stomach samples from 63 adult Imperial Cormorants during the chick-rearing period in 2014: 32 at Isla Arce and 31 at Isla Vernaci Este. We recorded 27 and 30 prey taxa in stomach samples at Isla Arce and Isla Vernaci Este, respectively, and at least 21 were common to both islands. Significant differences in diet composition in terms of importance by mass were found between young and old chick stages at Isla Arce but not at Isla Vernaci Este. Rock cod ( Patagonotothen spp.) were dominant at Isla Vernaci Este during both chick stages (75.7% and 86.5%, respectively). At Isla Arce, rock cod, Argentine anchovy ( Engraulis anchoita), and Argentine hake ( Merluccius hubbsi) contributed similarly to their diet (26-33%) during the young chick stage, whereas Argentine anchovy dominated during the old chick stage (76.6%). Diet composition in terms of importance by mass was significantly different between colonies. Imperial Cormorant consumed benthic, demersal, and pelagic prey, confirming plasticity in feeding habits, but their contribution differed depending on the site and chick stage. Our results suggest that diet assessments and monitoring the potential interaction between Imperial Cormorant and fisheries should not be based on information from a single breeding stage or location, but requires the analysis of diet composition throughout the breeding cycle with a representative sampling of the 17 colonies within the marine park. [ABSTRACT FROM AUTHOR]

This study provides the first quantification of plastic ingestion in the Tristram's Storm-petrel ( Oceanodroma tristrami ) in over 20 years. We found 100% plastic incidence in 57 chicks collected opportunistically over four breeding seasons (2007, 2010, 2011, 2012), with the mass of ingested plastic per individual ranging from 0.1 to 2.8 g (≤3.3% adult mass). While plastic occurred in every bird we examined, the proventriculus contained significantly more plastic, more fragments, and larger fragments than the gizzard. Most of the ingested plastic (97.5% by mass) consisted of fragments, ranging in length from 0.4 to 11.6 mm and ranging in surface area from 0.07 to 45.21 mm 2 . While fragments were ubiquitous, occurring in every proventriculus and gizzard we analyzed, Tristram's Storm-petrels also ingested foam, line and sheets. Digital analysis of 1425 ingested plastic fragments documented a wide range of colors, involving shades of white, yellow, orange, red, blue, green, and black. [ABSTRACT FROM AUTHOR]

Pair collaborative behavior may play an important role in avian reproduction. However, evidence for this mainly comes from certain ecological groups (e.g. passerines). We studied the coordination of parents in foraging and its effect on food provisioning rate and chick growth in a small seabird, the Dovekie (Little auk, Alle alle). The species exhibits a dual foraging strategy, where provisioning adults make foraging trips of short (mean ~2 h; to provide food for the chick) and long duration (mean ~ 13 h; mainly for adults self-maintenance, although the food is also brought to the chick). We expected that offspring would benefit if parents coordinate their foraging patterns: one making short trips in the time when the other performing the long one. We examined this hypothesis using Monte Carlo randomization tests on field data collected during observations of individually marked birds. We found that parents did indeed adjust provisioning, making their long and short trips in an alternating pattern with respect to each other. Furthermore, we found that a higher level of coordination is associated with a lower variability in the duration of inter-feeding intervals, although this does not affect chick growth. Nevertheless, our results provide compelling evidence on the coordinated behavior of breeding partners. [ABSTRACT FROM AUTHOR]

The article discusses fieldwork conducted on Marion Island, South Africa's Prince Edward Islands, during which breeding behavior in three colonies of Wandering albatross located in Macaroni Bay, Sealer's Beach, and Goney Plain from 2006 to 2009 was observed. Topics discussed include the presence of male and female Wandering albatross in the breeding colony during the pre-laying season, laying dates and periods of laying, and hatching dates and incubation periods.

Parental care in long-lived bird species involves a trade-off between the benefits of increasing the effort expended on current offspring and the costs that this represents for future reproductive output. Under regimes of high environmental variability, long-lived seabirds can adjust their breeding effort to buffer the negative effects of this variability on their offspring. However, the potential impacts of variation in breeding effort on offspring physiology in the short term and on longer-term survival are poorly understood. In this study, we manipulated brood age through a cross-fostering experiment to assess whether increasing or decreasing parental reproductive expenditure led to costs in Blue-footed Booby Sula nebouxii chicks. Specifically, we tested the consequences of altered parental reproductive expenditure on the offspring's physiological condition (plasma metabolites, heterophil to lymphocyte ratio (H/L) and body condition index ( BCI)) and survival. Offspring from broods in which parental investment was experimentally increased showed a lower BCI and lower alkaline phosphatase levels and higher H/L ratios than controls. Conversely, offspring showed the opposite pattern when reproductive expenditure was experimentally decreased. We observed no effects of manipulation of parental investment on triglyceride levels or on survival rates. Although our findings suggest that Blue-footed Booby parents have the ability to adjust their breeding effort according to the demands of their offspring, parental effort could influence the effect of hatching order by suppressing the aggressive tendency of the senior chick. [ABSTRACT FROM AUTHOR]

Mutton birds ( Puffinus griseus ) are wild seabird chicks traditionally harvested by Maori but available commercially for seasonal consumption in New Zealand. Little information is available on the nutritional content of the meat from these birds. Proximate analysis and amino and fatty acid composition of Mutton bird breast meat (MBBM) were measured over two harvesting seasons, 2007 and 2008. Protein content was lower, and fat and ash contents were higher ( P < 0.05) in meat from birds harvested in 2008 (18.5, 13.0 and 11.7%, respectively) compared with that from 2007 (20.3, 11.8 and 10.3%, respectively). Higher lysine concentrations and lower proline, cysteine and methionine were found in MBBM compared with literature values for beef, lamb and pork. The essential amino acid content in Mutton bird (41.7 and 38.4% for 2008 and 2007, respectively) was slightly lower than those reported for common meats (42–43%). Palmitic, arachidonic, DHA, stearic, EPA, and oleic were the major fatty acids (FA) detected in MBBM and accounted for approximately 60% of the FA. The cholesterol concentration was not affected by season. Seasonal variations MBBM existed which may be of little nutritional consequence but might be a useful indicator for ecological events including changing feed availability. [ABSTRACT FROM AUTHOR]

In several bird species, mothers that endow their eggs with additional resources benefit from more rapid development and more robust offspring. We examined egg size and associated life-history traits in 44 species of the slow-breeding procellariiform seabirds (albatrosses and petrels). The far distant foraging of some of the species should subject them to difficult ecological conditions and perhaps delays in return to the nest. Such delays might lead to poorer egg care by the remaining parent. To compensate, we predicted a positive association of egg size with foraging zone (offshore, near pelagic, far pelagic), and both with the length of incubation shifts. We tested this hypothesis and also examined egg size and fitness-related reproductive traits. Egg size scaled significantly and tightly with female body mass ( β = 0.72, R2 = 0.98). After influences of both size and phylogeny were removed, however, egg size was positively and significantly associated with both mean length of incubation shift and feeding zone ( r = 0.45 and 0.46, respectively), perhaps indicating a life-history syndrome of egg size, incubation, and distance that species go to forage during the breeding season, and supporting the compensation hypothesis. [ABSTRACT FROM AUTHOR]

The article discusses a study which examines and compares the diet between Black-legged Kittiwake adults and chicks in the southern Barents Sea. Findings show the lack of significant differences in the prey composition and prey size in the diets of both adults and chicks in the 2012 breeding season. It indicates the possible contribution of season and geography to the differences of diet among surface feeders.

The article discusses a study which examines the impact of disturbance by researchers on the breeding success of Atlantic puffins on Machias Seal Island, Maine. The impact on hatching and reproductive success of taking blood samples from adults during incubation and the difference of chick growth rates between experimental burrows and control subjects are observed. Findings show the lack of significant differences in hatching, breeding, and chick growth between the examined subjects.

Crevice-nesting seabirds are notoriously difficult to monitor. We present a survey design and analysis that estimates both colony area and geographic extent, using indirect evidence to determine whether a cell is 'occupied.' The approach is to define a grid of cells across potential habitat and randomly sample small plots within each cell, surveying for signs of occupancy. Visiting ≥1 plot cell−1 provides a basis for mapping geographic extent. Occupancy models are used to estimate colony area, probability of detection for an occupied cell, and standard errors for all estimated parameters (allowing for statistical comparisons across surveys or colonies). We estimated the area of a colony of Least Auklets ( Aethia pusilla) and Crested Auklets ( A. cristatella) on Segula Island, Aleutian Archipelago, Alaska, in 2006, and use this as an example of how to adapt the survey design to the logistical constraints common in seabird colony surveys. Surveying only a handful of sample plots of ∼16 m2 in each ∼2,500-m2 cell in the grid was adequate to estimate the detection bias from spatial subsampling, correcting a >50% underestimate of colony area due to plots without evidence having been interpreted as unoccupied cells. [ABSTRACT FROM AUTHOR]

The body condition of altricial seabird chicks is directly related to the amount of food received from their parents, which depends on feeding conditions at sea. An index of body condition is therefore a useful tool for assessing variation in food availability between different breeding colonies. Quantile regression techniques were used to develop a body condition index for African penguinSpheniscus demersuschicks, based on maximum and minimum growth relative to structural size. This is considered the most appropriate index for comparing the body condition of groups of chicks, varying in size and of unknown age, between breeding colonies. Based on this study, recommendations are made with regard to morphometric measurements, sample size and the sampling interval required to compare effectively the condition of African penguin chicks between breeding colonies throughout their distributional range. [ABSTRACT FROM AUTHOR]

Highlights: [•] We quantified marine debris ingestion in stranded Short-tailed shearwaters. [•] More than 2/3 of all birds ingested debris. [•] Juvenile birds were more likely to ingest debris than adults were. [•] Debris ingestion did not vary by sex. [•] Birds preferentially select for hard plastic, rubber and balloons. [Copyright &y& Elsevier]

Blood and feathers are the most targeted tissues for isotopic investigations in avian ecology, primarily because they can be easily and non-destructively sampled on live individuals. Comparing blood and feather isotopic ratios can provide valuable information on dietary shifts, trophic specialization and migration patterns, but it requires a good knowledge of the isotopic differences between the two tissues. Here, δC and δN values of whole blood (in blood cells of a few species) and simultaneously grown body feathers were measured in seabird chicks to quantify the tissue-related isotopic differences. Seabirds include 27 populations of 22 wild species that were sampled in 2000-2008, and a review of the literature added 8 groups (including adult birds) to the analysis. The use of a large data set that overall encompasses wide δC and δN ranges allowed us to depict for the first time accurate relationships between blood and feather isotopic ratios across avian taxa. Blood was impoverished in C and generally in N compared with feathers. Both mean δC and δN values of feathers and blood were highly positively and linearly related [feather δC = 0.972 (±0.020) blood δC + 0.962 (±0.414), and feather δN = 1.014 (±0.056) blood + 0.447 (±0.665), respectively; both P < 0.0001]. The regressions should be applied to mathematically correct feather or whole blood δC and δN values when comparing isotopic ratios within and between ecological studies on birds. [ABSTRACT FROM AUTHOR]

The article explores the success in reproduction and growth of chicks of Pacific gulls Larus pacificus in the Furneaux Group, Tasmania, conducted between October 16, 2003 and January 2, 2004. 45% of the eggs hatched, with differences in hatching rates among islands. Factors that threatened Pacific gulls were increased urbanisation, anthropogenic disturbance and intra-specific competition from Kelp gulls Larus dominicanus.

Life history theory predicts that parents will balance benefits from investment in current offspring against benefits from future reproductive investments. Long-lived organisms are therefore less likely to increase parental effort when environmental conditions deteriorate. To investigate the effect of decreased foraging capacity on parental behaviour of long-lived monogamous seabirds, we experimentally increased energy costs for chick-rearing thick-billed murres (Uria lomvia). Handicapped birds had lighter chicks and lower provisioning rates, supporting the prediction that long-lived animals would pass some of the costs of impaired foraging ability on to their offspring. Nonetheless, handicapped birds spent less time underwater, had longer inter-dive surface intervals, had lower body mass, showed lower resighting probabilities in subsequent years and consumed fewer risky prey items. Corticosterone levels were similar between control and handicapped birds. Apparently, adults shared some of the costs of impaired foraging, but those costs were not measurable in all metrics. Handicapped males had higher plasma neutral lipid concentrations (higher energy mobilisation) and their chicks exhibited lower growth rates than handicapped females, suggesting different sex-specific investment strategies. Unlike other studies of auks, partners did not compensate for handicapping, despite good foraging conditions for unhandicapped birds. In conclusion, parental murres and their offspring shared the costs of experimentally increased foraging constraints, with females investing more than males. [ABSTRACT FROM AUTHOR]

The nationally endangered breeding population of Common Terns Sterna hirundo in the German Wadden Sea has been rapidly declining in recent years. In an attempt to identify the causes for this decline we analysed the demography of the Jade Bay population based on the 'Banter See' colony. This colony has been intensively studied for over 18 years and has been declining in recent years. We estimated apparent survival rates of breeders and non-breeders of different ages using multi-state capture-recapture models based on individual life histories. The population growth rates of the Banter See colony and Lower Saxony population were estimated, and possible future trajectories were projected using a matrix model approach. Adult survival rates (0.9) have remained constant, but since 2002 subadult survival has decreased significantly (0.36-0.28). We found significantly lower breeding success as well as lower and delayed recruitment. These changes in vital rates probably caused the shift in the Banter See colony growth rate from an increasing phase before 2002 to a declining phase after and most likely occurred due to low pelagic prey fish stocks in the North Sea, the most important food source for terns in the Wadden Sea. Should the population decline continue at the current rates, the Banter See colony could decrease by 11% and the Lower Saxony Wadden Sea population by an alarming 57% between 2009 and 2015. Zusammenfassung Seeschwalben mit Problemen: Demographische Konsequenzen von geringem Bruterfolg und geringer Rekrutierung in einer Flussseeschwalben-Population im Deutschen Wattenmeer Die Brutpopulation der Flussseeschwalbe Sterna hirundo im niedersächsischen Wattenmeer hat in den letzten Jahren einen starken Rückgang erfahren. Diese Entwicklung ist bedenklich, da diese Art seit 2007 auf der Roten Liste als stark gefährdet eingestuft wird. Um Ursachen für den Rückgang in der Zahl der Brutpaare festzustellen, wurde in dieser Studie die Demographie der Flussseeschwalbenpopulation am Jadebusen untersucht, mit besonderem Augenmerk auf die Kolonie 'Banter See' in Wilhelmshaven. Diese Kolonie wird seit über 18 Jahren eingehend untersucht und zeigt ebenfalls einen rückläufigen Trend. Überlebensraten von Brütern und Nichtbrütern verschiedener Altersgruppen wurden anhand eines Multi-State Capture-Recapture Modells, basierend auf individuellen Lebensgeschichten, ermittelt. Die Wachstumsrate der Banter See Kolonie wurde in zwei Phasen unterteilt: eine wachsende Phase vor 2002 und eine abnehmende Phase danach. Diese Entwicklung wurde durch Änderungen in wesentlichen demographischen Raten hervorgerufen, so wie signifikant geringerer Bruterfolg, signifikant weniger und spätere Rekrutierung und signifikant geringere Überlebensraten zweijähriger Vögel seit 2002 (von 36% auf 29%). Die Überlebensraten adulter Vögel (90%) dagegen blieben in dieser Zeit konstant. Die Änderungen in demographischen Raten ist höchstwahrscheinlich auf niedrige Herings-Clupea harengus und Sprottenbestände Clupea sprattus in der Nordsee zurückzuführen, die die wichtigste Nahrungsquelle für Seeschwalben im Wattenmeer darstellen. Andere Flussseeschwalbenkolonien im Wattenmeer erlebten einen wesentlich schlimmeren Rückgang in der Zahl der Brutpaare und haben begonnen sich aufzulösen. Sollte der Rückgang der Brutpaare im derzeitigen Ausmaß weitergehen, könnte sich die Banter See Kolonie bis 2015 um bis zu 11% der Brutpopulation von 2009 verringern, während die gesamte Wattenmeer Population in der Zeit sogar um alarmierende 57% der Bestände von 2008 abzunehmen droht. [ABSTRACT FROM AUTHOR]

Within the past several decades, seabird populations have been actively restored in locales where they were reduced or extirpated. Chick translocation, acoustic vocalization playbacks, and decoys are now used widely to lure breeding seabirds to restoration sites. In this first worldwide review of seabird restoration projects we evaluate the factors affecting project success or failure and recommend future directions for management. We identified 128 active restoration projects that were implemented to protect 47 seabird species in 100 locales spanning 14 countries since active restoration methods were pioneered in 1973. Active seabird restoration can achieve conservation goals for threatened and endangered species, and for species affected by anthropogenic impacts (e.g., oil spills, invasive species, fisheries). It also can be used to relocate populations from undesired breeding locales to more favorable locations, and to establish multiple breeding locations to reduce risks posed by catastrophic events. Active restoration can help to restore ecological processes, as large seabird colonies function to cycle marine nutrients to terrestrial ecosystems and create habitats for commensal species. Active restoration is especially appropriate where the original causes of decline are no longer working to suppress colony establishment and growth. Successful restoration efforts require careful planning and long-term commitments. We introduce the different forms of active seabird restoration techniques, review their utility for different seabird species, and use case studies to suggest how to optimize this technique to restore seabird species globally. Wildlife managers can use this review to guide their seabird restoration projects in the planning, implementation, and monitoring stages; tailor their restoration to seabird-specific life histories; and identify areas for further research to improve restoration utility in the future. © 2011 The Wildlife Society. [ABSTRACT FROM AUTHOR]

Breeding animals face important time and energy constraints when caring for themselves and their offspring. For long-lived species, life-history theory predicts that parents should favor survival over current reproductive attempts, thus investing more into their own maintenance than the provisioning of their young. In seabirds, provisioning strategies may additionally be influenced by the distance between breeding sites and foraging areas, and offshore and inshore species should thus exhibit different strategies. Here, we examine the provisioning strategies of an inshore seabird using a long-term data set on more than 200 Little Penguins, Eudyptula minor. They alternated between two consecutive long and several short foraging trips all along chick rearing, a strategy almost never observed for inshore animals. Short trips allowed for regular provisioning of the chicks (high feeding frequency and larger meals), whereas long trips were performed when parent body mass was low and enabled them to rebuild their reserves, suggesting that adult body condition may be a key factor in initiating long trips. Inshore seabirds do use dual strategies of alternating short and long trips, but from our data, on a simpler and less flexible way than for offshore birds. [ABSTRACT FROM AUTHOR]

The article presents a study using the Herring Gull to examine the effects of nest density on chick's growth and survival. It notes that the findings of the study reveal that chicks grown in dense subcolonies have higher growth rate compared with those reared in isolated areas. Survival of chicks depends on the hatch date, hatch order, and hatch weight.

Abstract: The efficiency of antioxidant defenses and relationship with body burden of metal and organic contaminants has not been previously investigated in arctic seabirds, neither in chicks nor in adults. The objective of this study was to compare such defenses in chicks from three species, Black-legged kittiwake (Rissa tridactyla), Northern fulmar (Fulmarus glacialis), and Herring gull (Larus argentatus), and the relationship with tissue concentrations of essential metals such as selenium and iron and halogenated organic compounds, represented by polychlorinated biphenyl (PCB). The results showed significant species-specific differences in the antioxidant responses which also corresponded with metal and PCB levels in different ways. The capability to neutralize hydroxyl radicals (TOSC-HO•) and the activities of catalase and Se-dependent glutathione peroxidases (GPX) clearly increased in species with the higher levels of metals and PCBs, while the opposite trend was observed for Se-independent GPX, TOSC against peroxyl radicals (ROO•) and peroxynitrite (ONOOH). Less clear relationships were obtained for glutathione levels, GSH/GSSG ratio, glutathione reductase and superoxide dismutase. The results showed differences in antioxidant efficiency between the species, and some of these defenses exhibited dose–response-like relationships with measured levels of selenium, iron and ΣPCBs. PCBs, selenium and iron levels were positively related to the responses of antioxidants with potential to reduce HO•/H2O2 (Se-dependent GPX, CAT and TOSC against HO•). However, direct causal relationships between antioxidant responses and contaminant concentrations could not be shown on individual level. Varying levels of metals and contaminants due to different diet and age were probably the main explanations for the species differences in antioxidant defense. [Copyright &y& Elsevier]

Pelagic seabirds are central place foragers during breeding and variation in foraging trip duration and range reflect differences in diet and chick provisioning, through the exploitation of divergent habitats of varying productivity. We tested whether these relationships hold in small procellarriids by equipping chick-rearing Cook’s petrel Pterodroma cookii (200 g) with geolocation-immersion loggers, conducting isotope analysis of blood and measuring chick meal mass following foraging trips of varying duration. Cook’s petrel tracked during chick rearing from Little Barrier Island (LBI) and Codfish Island (CDF), New Zealand had larger maximum ranges during longer foraging trips. Blood nitrogen isotope signatures (δN) of adults were significantly higher after foraging trips of longer duration, but not of greater maximum range. There was no significant relationship between blood carbon isotope signatures (δC) and foraging trip characteristics. Proportion of time spent on the sea surface and the mass of the meal brought back to chicks were consistently greater for Cook’s petrel with larger maximum ranges, which in the case of birds from CDF coincided with productive subtropical convergence zone habitats. As predicted, trip duration reflected divergent foraging behaviours in Cook’s petrel during breeding. We suggest that the availability of different prey is a key factor governing at-sea distributions and dietary composition of this species. [ABSTRACT FROM AUTHOR]

Bird species from the order Procellariiformes or petrels, including the northern fulmar (Fulmarus glacialis), produce high lipid and high energy content stomach oils from the prey they consume, which enables them to exploit distant marine food sources. Stomach oils are also used as a food source for chicks and for defensive purposes. Samples of stomach oils from two Arctic colonies, St. George Island Alaska, USA and Cape Vera, Devon Island Nunavut, Canada, were collected and analyzed for organochlorine contaminants. ΣPCB concentrations ranged from 13 to 236 ng g-1 wet weight (ww) and ΣDDT concentrations from 5 to 158 ng g-1 ww and were similar in both sites, though differences in chemical signatures were apparent. Stomach oils are a rich energy source; however, they may also provide a higher dose of contaminants per unit energy than the direct consumption of prey items, as illustrated using mass and energy balance calculations to estimate chick exposure to ΣDDT for hypothetical stomach oil and whole prey diets. The results of this study suggest that stomach oils are an important vector of organochlorine contaminants to chicks and should be considered in future risk assessments of northern fulmars and other species of petrels. To our knowledge this is the first study of stomach oils as an overlooked vector of organochlorine contaminants to chicks and as a potentially valuable medium for dietary analysis and noninvasive biomonitoring both of petrel dietary exposure and of marine contaminant concentrations. [ABSTRACT FROM AUTHOR]

Abstract: The ingestion of plastic marine debris is a chronic problem for some of the world’s seabird species, contributing to reduced chick survival, population declines, and deposition of contaminants via absorption in birds’ gastrointestinal tract. We analysed the frequency of ingested plastic in chick meals delivered by adults in four species of auklet – Crested (Aethia cristatella), Least (A. pusilla), Parakeet (A. psittacula), and Whiskered (A. pygmaea) – from three breeding colonies in the Aleutian Islands, Alaska, USA over a 14-year period from 1993 to 2006. Among 2541 chick meals, we found plastic in only one – from a Whiskered Auklet on Buldir Island in 1993. While adult Parakeet Auklets have a high frequency of plastic ingestion (over 90%), no chick meals contained plastic. Unlike other seabirds, the planktivorous auklets do not appear to offload plastic to their chicks, and we conclude that auklet chicks are probably at a low risk of contamination from plastic debris. [ABSTRACT FROM AUTHOR]

Behavioral and/or developmental plasticity is crucial for resisting the impacts of environmental stressors. We investigated the plasticity of adult foraging behavior and chick development in an offshore foraging seabird, the black noddy (Anous minutus), during two breeding seasons. The first season had anomalously high sea-surface temperatures and 'low' prey availability, while the second was a season of below average sea-surface temperatures and 'normal' food availability. During the second season, supplementary feeding of chicks was used to manipulate offspring nutritional status in order to mimic conditions of high prey availability. When sea-surface temperatures were hotter than average, provisioning rates were significantly and negatively impacted at the day-to-day scale. Adults fed chicks during this low-food season smaller meals but at the same rate as chicks in the unfed treatment the following season. Supplementary feeding of chicks during the second season also resulted in delivery of smaller meals by adults, but did not influence feeding rate. Chick begging and parental responses to cessation of food supplementation suggested smaller meals fed to artificially supplemented chicks resulted from a decrease in chick demands associated with satiation, rather than adult behavioral responses to chick condition. During periods of low prey abundance, chicks maintained structural growth while sacrificing body condition and were unable to take advantage of periods of high prey abundance by increasing growth rates. These results suggest that this species expresses limited plasticity in provisioning behavior and offspring development. Consequently, responses to future changes in sea-surface temperature and other environmental variation may be limited. [ABSTRACT FROM AUTHOR]

Prolonged abnormal vomiting causes metabolic alkalosis.Many seabirds are known to feed their chicks by regurgitation. We hypothesized that metabolic alkalosis occurs in seabirds even under natural conditions during the breeding season. Adelie penguins Pygoscelis adeliae feed their chicks by regurgitating food for 50-60 d until the chicks fledge. In this study, the concentrations of Cl-, HCO3 -, Na+, K+, pH, and Pco2 in the blood of breeding Adelie penguins were measured throughout the chick-rearing season. The pH of penguin venous blood shifted from 7.54 in the guarding period to 7.47 in the crèche period. Decreasing Cl- and increasing HCO3 blood concentrations in parents were associated with increasing mass of their brood in the guarding period, the early phase of the rearing season, indicating that regurgitating to feed chicks causes loss of gastric acid and results in relative metabolic alkalosis. The inverse trend was observed during the crèche period, the latter phase of the rearing season, when parents spent more time at sea and have fewer opportunities for gastric acid loss. This was assumed to be the recovery phase. These results indicate that regurgitation might cause metabolic alkalosis in breeding Adelie penguins. To our knowledge, this is the first report to indicate that seabirds exhibit metabolic alkalosis due to regurgitation to feed chicks under natural conditions. [ABSTRACT FROM AUTHOR]

The article presents a study which examined the diets of rhinoceros auklets Cerorhinca monocerata breeding in Hokkaido, Japan as well as the relationship between temporal changes in the marine ecosystems of the region. The study found that there were no differences in the diets of rhinoceros auklets between age categories. Moreover, it revealed no differences in the occurrence of Japanese sandlance Ammodytes personatus, Japanese Sea greenling Pleurogrammus azonus and Japanese anchovy Engraulis japonicus between adult and chick diets during the early chick-rearing period.

The article discusses the findings of a study which examined the movements of the Kelp Gull Larus dominicanus vetula to, from and within southern South Africa. Using data from a database held by the South African Bird Ringing Unit (SAFRING), the re-sightings of live and recoveries of dead-ringed birds were analyzed. Several maps are presented showing the localities in southern South Africa where Kelp Gull Larus dominicanus vetula chicks and adults were ringed, flagged or re-sighted. A common feature of most seabird species is the tendency for young birds to disperse farther from breeding colonies as compared to adults.

We examined how short-term impacts of experimentally increased foraging effort by one parent reverberate around the family in a monomorphic seabird (little auk, Alle alle), and whether these effects depend on offspring sex. In many species, more effort is required to rear sons successfully than daughters. However, undernourishment may have stronger adverse consequences for male offspring, which could result in a lower fitness benefit of additional parental effort when rearing a son. We tested two alternative hypotheses concerning the responses of partners to handicapping parents via feather clipping: partners rearing a son are (1) more willing or able to compensate for the reduced contribution of their mate, or (2) less willing or able to compensate, compared to those rearing a daughter. Hypothesis 1 predicts that sons will be no more adversely affected than daughters, and the impact on parents will be greater when rearing a son. Hypothesis 2 predicts that sons will be more adversely affected than daughters, and parents raising a son less affected. Although experimental chicks of both sexes fledged in poorer condition than controls, sons attained higher mass and more rapid growth than daughters in both groups. Clipped parents lost a similar proportion of their initial mass regardless of chick sex, whereas partners of clipped birds lost more mass when rearing a son. These results support hypothesis 1: impacts of increased foraging effort by one parent were felt by offspring, regardless of their sex, and by the partners of manipulated birds, particularly when the offspring was male. [Copyright &y& Elsevier]

Parental age, body condition, and food availability have been found to influence breeding parameters in seabirds, such as clutch size, number of chicks hatched and fledged, hatching, fledging, and reproductive success. In this paper we analyze the influence of parental age and body condition estimated by body mass, and food availability estimated from catch per unit effort (CPUE) statistics for Pacific sardine (Sardinops caeruleus) + northern anchovy (Engraulis mordax) by the local fishing fleet, on the breeding parameters of the Heermann's Gull (Larus heermanni; a vulnerable species according to Mexican federal law) nesting in Isla Rasa, Gulf of California, Mexico. Results are based on data from 1123 recaptures of known-age individuals, ranging from 4 to 13 years of age, during seven observation years between 1989 and 1997. Ages of mated male and female gulls were positively correlated. Breeding parameters showed their lowest values in 1992, an El Niño year in which the birds also showed significantly lower individual masses for both males and females, and in which the local CPUE of sardine + anchovies was lowest. All breeding parameters increased significantly with parental age and were highest at 10-12 years. No significant statistical interactions were found between food availability and parental age on the breeding parameters. Through a path analysis we found that there is a strong chained relationship between variables: food availability, which is strongly driven by oceanographic conditions, affects both the survival of eggs into hatchlings and the survival of hatchlings into fledglings. This external factor and parental age, a biological factor intrinsic to each nesting couple, explain 41% of the observed between-nest variation in fledgling success. [ABSTRACT FROM AUTHOR]

The article presents a study on little penguins Eudyptula minor on Phillip Island, Southeastern Australia. It examines the association of the bird's breeding variables with regional sea surface temperature (SST) at different seasons of the year by using a 9-year data to test the study's statistical predictive models. In the first three months of the year, the date of egg-laying, chicks fledged per pair, and chick mass were found to be correlated with SST. The model predicts that an increase in SST will help improve the growth of the number of little penguins on the island.

1. We studied chick diet in a known-age, sexed population of a long-lived seabird, the Brünnich's guillemot ( Uria lomvia), over 15 years ( N = 136; 1993–2007) and attached time–depth–temperature recorders to examine foraging behaviour in multiple years ( N = 36; 2004–07). 2. Adults showed specialization in prey fed to offspring, described by multiple indices calculated over 15 years: 27% of diet diversity was attributable to among-individual variation (within-individual component of total niche width = 0·73); average similarity of an individual's diet to the overall diet was 65% (mean proportional similarity between individuals and population = 0·65); diet was significantly more specialized than expected for 70% of individuals (mean likelihood = 0.53). These indices suggest higher specialization than the average for an across-taxa comparison of 49 taxa. 3. Foraging behaviour varied along three axes: flight time, dive depth and dive shape. Individuals showed specialized individual foraging behaviour along each axis. These foraging strategies were reflected in the prey type delivered to their offspring and were maintained over scales of hours to years. 4. Specialization in foraging behaviour and diet was greater over short time spans (hours, days) than over long time spans (years). Regardless of sex or age, the main component of variation in foraging behaviour and chick diet was between individuals. 5. Plasma stable isotope values were similar across years, within a given individual, and variance was low relative to that expected from prey isotope values, suggesting adult diet specialized across years. Stable isotope values were similar among individuals that fed their nestlings similar prey items and there was no difference in trophic level between adults and chicks. We suggest that guillemots specialize on a single foraging strategy regardless of whether chick-provisioning and self-feeding. With little individual difference in body mass and physiology, specialization likely represents learning and memorizing optimal feeding locations and behaviours. 6. There was no difference in survival or reproductive success between specialists and generalists, suggesting these are largely equivalent strategies in terms of evolutionary fitness, presumably because different strategies were advantageous at different levels of prey abundance or predictability. The development of individual specialization may be an important precursor to diversification among seabirds. [ABSTRACT FROM AUTHOR]

1. In long-lived animals with delayed maturity, the non-breeding component of the population may play an important role in buffering the effects of stochastic mortality. Populations of colonial seabirds often consist of more than 50% non-breeders, yet because they spend much of their early life at sea, we understand little about their impact on the demographic process. 2. Using multistate capture–mark–recapture techniques, we analyse a long-term data set of individually identifiable common guillemots, Uria aalge Pont., to assess factors influencing their immature survival and two-stage recruitment process. 3. Analysis of the distribution of ringed common guillemots during the non-breeding season, separated by age classes, revealed that all age classes were potentially at risk from four major oil spills. However, the youngest age class (0–3 years) were far more widely spread than birds 4–6 years old, which were more widely spread than birds aged 6 and over. Therefore the chance of encountering an oil spill was age-dependent. 4. A 2-year compound survival estimate for juvenile guillemots was weakly negatively correlated with winter sea-surface temperature, but was not influenced by oil spills. Non-breeder survival did not vary significantly over time. 5. In years following four oil spills, juvenile recruitment was almost double the value in non-oil-spill years. Recent work from Skomer Island showed a doubling of adult mortality associated with major oil spills, which probably reduced competition at the breeding colony, allowing increased immature recruitment to compensate for these losses. We discuss the implications of compensatory recruitment for assessing the impact of oil pollution incidents. [ABSTRACT FROM AUTHOR]

The article discusses a study which compared the composition and overlap in the chick diets of the two most abundant auks in the Northwest Atlantic, the Common Murre and the Atlantic Puffin. The researchers assessed the manner in which auks with different foraging strategies and physiological constraints imposed by differences in body size and prey-loading meet the energy demands of reproduction. It was found that Puffin chicks did not exhibit differences in mass at given wing lengths in 2004 and 2005.

The emperor penguin (Aptenodytes forsteri) is extremely dependent on the extent and stability of sea ice, which may make the species particularly susceptible to environmental change. In order to appraise the stability of the emperor penguin populations at six colonies in the western Ross Sea, we used linear regression analysis to evaluate chick abundance trends (1983-2005) and Pearson's r correlation to assess their relation to two local and two large-scale climate variables. We detected only offe significant abundance trend; the Cape Roget colony increased from 1983 to 1996 (n = 6). Higher coefficients of variation in chick abundances at smaller colonies (Cape Crozier, Beaufort Island, Franklin Island) suggest that such colonies occupy marginal habitat, and are more susceptible to environmental change. We determined chick abundance to be most often correlated with local Ross Sea climate variables (sea ice extent and sea surface temperature), but not in consistent patterns across the colonies. We propose that chick abundance is most impacted by fine scale sea ice extent and local weather events, which are best evaluated by on-site assessments. We did not find sufficient evidence to reject the hypothesis that the overall emperor penguin population in the Ross Sea was stable during this period. [ABSTRACT FROM AUTHOR]

We measured resting and peak metabolic rates (RMR and PMR, respectively) during development of chicks of seven species of shorebirds: least sandpiper (Calidris minutilla; adult mass 20—22 g), dunlin (Calidris alpina; 56—62 g), lesser yellowlegs (Tringa flavipes 88—92 g), short-billed dowitcher (Limnodromus griseus; 85—112 g), lesser golden plover (Pluvialis dominicana; 150—156 g), Hudsonian godwit (Limosa haemastica; 205—274 g), and whimbrel (Numenius phaeopus; 380 g). We tested two opposing hypotheses: the growth rate-maturity hypothesis, which posits that growth rate in chicks is inversely related to functional maturity of tissues, and the fast growth rate-high metabolism hypothesis, which suggests that rapid growth is possible only with a concomitant increase in either RMR or PMR. We have found no evidence that chicks of shorebirds with fast growth rates have lower RMRs or lower PMRs, as would be predicted by the growth rate-maturity hypothesis, but our data suggested that faster-growing chest muscles resulted in increased thermogenic capacity, consistent with the fast growth-high metabolism hypothesis. The development of homeothermy in smaller species is a consequence primarily of greater metabolic intensities of heat-generating tissues. The maximum temperature gradient between a chick's body and environment that can be maintained in the absence of a net radiative load increased rapidly with body mass during development and was highest in least sandpipers and lowest among godwits. Chicks of smaller species could maintain a greater temperature gradient at a particular body mass because of their higher mass-specific maximum metabolic rates. [ABSTRACT FROM AUTHOR]

The article discusses a study which examines the diet of Greater Crested tern chicks at Robben Island, South Africa from 2013 to 2014. Observations were conducted by photographing adults returning to their nests with prey in their bill and by recording videos of feeding events. Findings show that 95 insects were brought back to the bird's colony.

The article reports on the evacuation of the chicks of short-toed albatross, a vulnerable specie of albatross, from an active volcano in Torishima, Japan. It mentions that the chicks are transferred to the former breeding site of short-toed albatross in Mukojima, Japan with the use of a helicopter. According to the author, the chicks, which will be fed by hand until their maturity, are moved before they develop a geographic imprint of the breeding island. As a result, Mukojima will be established as their breeding colony when the chicks are sexually mature.