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Climate warming is pronounced in the Arctic and migratory birds are expected to be among the most affected species. We examined the effects of local and regional climatic variations on the breeding phenology and reproductive success of greater snow geese ( Chen caerulescens atlantica), a migratory species nesting in the Canadian Arctic. We used a long-term dataset based on the monitoring of 5447 nests and the measurements of 19 234 goslings over 16 years (1989–2004) on Bylot Island. About 50% of variation in the reproductive phenology of individuals was explained by spring climatic factors. High mean temperatures and, to a lesser extent, low snow cover in spring were associated with an increase in nest density and early egg-laying and hatching dates. High temperature in spring and high early summer rainfall were positively related to nesting success. These effects may result from a reduction in egg predation rate when the density of nesting geese is high and when increased water availability allows females to stay close to their nest during incubation recesses. Summer brood loss and production of young at the end of the summer increased when values of the summer Arctic Oscillation (AO) index were either very positive (low temperatures) or very negative (high temperatures), indicating that these components of the breeding success were most influenced by the regional summer climate. Gosling mass and size near fledging were reduced in years with high spring temperatures. This effect is likely due to a reduced availability of high quality food in years with early spring, either due to food depletion resulting from high brood density or a mismatch between hatching date of goslings and the timing of the peak of plant quality. Our analysis suggests that climate warming should advance the reproductive phenology of geese, but that high spring temperatures and extreme values of the summer AO index may decrease their reproductive success up to fledging. [ABSTRACT FROM AUTHOR]

Abstract: Although maras (Dolichotis patagonum) are among the most representative mammals of South America, knowledge on the ecological processes affecting their conservation is scarce. In particular, the study of habitat requirements and its relationship with breeding success is necessary to identify possible threats and develop conservation action for this endemic mammal. I investigated habitat selection patterns by maras and their relationship with breeding success in Península Valdés, Argentine Patagonia. Maras bred from mid-August to late December, and they tended to build the breeding warrens in open, grass-dominated habitats more than expected while avoided closed habitats dominated by taller shrubs. Mean number of breeding adults per warren was 4.26, while mean number of pups born per warren was 4.46. Overall, 30 (45%) of 67 pups survived until the 6th week of life, but pups born in warrens located in open habitats survived significantly better than pups born in warrens located in closed habitats (50% vs. 30% of the pups born). As grass-dominated areas uphold the highest densities of domestic sheep and habitat modification due to overgrazing is a widespread process across arid Patagonia, effects on the availability of suitable breeding sites for maras are likely to occur and require further investigation. [Copyright &y& Elsevier]

The blood parameters—red blood cell (RBC) count, hematocrit (Ht), hemoglobin concentration (Hb), mean corpuscular volume (MCV), mean corpuscular hemoglobin (MCH), and mean corpuscular hemoglobin concentration (MCHC)—were studied for the first time in free ranging pigeons Columba livia f. urbana. The aim of the study was to establish a set of reference values for this ubiquitous urban species and to examine a potential influence of the factors such as sex and phase of the breeding cycle on the hematological parameters. Blood was sampled from the adult individuals of both sexes during the breeding cycle. Significant variations in Ht and Hb were observed, while RBC count remained unchanged. The lower hematocrit value and hemoglobin concentration found in both males and females during molt probably resulted from the increase of plasma volume not accompanied by an increase in RBC. On the other hand, a significant physiological stress of nutritional deficiency during this energy-consuming stage may manifest itself in the decreased Ht and Hb values. The higher values of Ht and Hb during the laying phase could be related to the dehydration status. There were no overall differences in MCV, MCH, and MCHC values in either of the breeding stage. A lack of sex dimorphism in the measured and calculated blood parameters was apparent. Data collected herein contribute to the better understanding of general physiology of the ubiquitous urban species. The knowledge of variation in the blood indexes with respect to sex and breeding stage is crucial before blood parameters can provide an useful information on physical condition of the bird. [ABSTRACT FROM AUTHOR]

Abstract: Haematocrit measurements and plasma protein electrophoresis were carried out in female pigeons (Columba livia) during the breeding cycle. Non-laying birds showed higher (p <0.001) haematocrit values than those involved in courtship and mating, nest-building, incubation and feeding and brooding. Significant differences in relative percentage of various plasma protein fractions were observed as a function of breeding. Haematocrit could be a useful index to the non-laying status of pigeons like that in chickens, Gallus domesticus. [Copyright &y& Elsevier]

We describe how levels of glucose, triglyceride, fatty acids, glycerol, β-hydroxybutyrate, uric acid, and corticosterone varied in the blood of Pied Flycatchers (Ficedula hypoleuca) during three breeding cycles. Data are for egg-laying and incubating females, and adults of both sexes that were caring for nestlings. Egg-laying females had high blood levels of triglyceride, fatty acids, and uric acid. Triglyceride and fatty acids decreased steadily with the laying of each new egg, whereas uric acid increased. This pattern of change in blood lipids would be expected as the number of ovarian follicles that are loaded with yolk precursors and subsequently ovulated diminishes. The rising uric acid level probably reflects increased consumption and subsequent catabolism of dietary proteins. Corticosterone levels were low suggesting that food was readily available for the production of eggs. Incubating females used fat as fuel, most of which was probably of dietary origin given their low blood triglyceride coupled with high fatty acid, glycerol, and corticosterone levels, and stable, high body weight. None of the birds' plasma constituents varied with clutch size or the length of time the females had been incubating. Females rearing broods exhibited low triglyceride and high β-hydroxybutyrate and corticosterone levels. Blood glycerol and free fatty acids rose steadily as a function of nestling age, while glucose and body weight declined. Such a picture suggests that females underwent transient bouts of fasting while providing their chicks with food. Meanwhile males were lighter than their mates and had lower blood metabolite levels, but their blood corticosterone was elevated and correlated with uric acid levels, suggesting that they took more time to forage for themselves than females. None-theless, they too lost weight during this stage of the breeding cycle. [ABSTRACT FROM AUTHOR]

Changes in the blood profile of domestic pigeons (Columba livia) were studied during growth and breeding cycle. Counts of erythrocytes and leucocytes, and values of mean corpuscular volume (MCV), mean corpuscular haemoglobin (MCH), blood volume, plasma volume (BV), width of erythrocytes, and length, width and volume of erythrocyte nuclei of squabs almost reached adult values by the 4th week of age. During courtship and mating, while the level of plasma glucose increased, those of albumin, potassium, cholesterol, calcium and uric acid decreased. At nest-building, plasma albumin and plasma calcium increased significantly. The initial phase of incubation showed an elevation in plasma calcium and a decline in cholesterol and sodium, whereas mid-phase of incubation indicated a marked rise in cholesterol and uric acid. Terminal phase of incubation had significantly low plasma protein level. During feeding and brooding period, a significant rise in sodium, protein and glucose levels and a fall in calcium were observed. Following egg-laying, there was a significant rise in calcium and a drop in protein, haemoglobin, cholesterol, sodium and MCH values. Concomitant with the phenomenal rate of growth of squabs, their haematological indices neared adult values by the 4th week of age and during breeding activity significant changes in blood values occurred. [Copyright &y& Elsevier]

In the years 1997–2001, I observed 28 broods of the Citrine Wagtail ( Motacilla citreola) in the Gulf of Gdańsk region. First birds arrived at the study area at the end of April. A successful breeding cycle lasted about 1 month and included: 3–4 days of nest building, 1–2 days of a “break”, 4–6 days of egg laying, 11–12 days of incubation, and 10–13 days of parental care of chicks in the nest. Females started to lay eggs at the beginning of May. The most common clutch-size was 5 eggs. Hatching success was 55.3%. On average, 2.6 chicks hatched in a nest, the final fledging success reached 38.1% and an average 1.8 chicks left the nest. Nests were always on the ground and were situated in tufts or in thick vegetation. Most entrances faced south-east. The mean external diameter of nests was 10.1 cm, the internal diameter, presented as “width” and “length”, averaged 6.3 and 6.8 cm, respectively, and the mean depth of cup was 3.9 cm. Eighty-six measured eggs were similar in shape and colour to the eggs of Yellow Wagtail ( M. flava) . Their mean width was 14.16 mm, and the length 18.40 mm. The growth and plumage development of nestlings is reported. To estimate the nestlings’ age a multiple regression equation was established with the measurements of highest correlation coefficients, i.e. wing and tarsus length: D=0.12W+0.23T–0.23 (where: D = day of life, W = wing length, T = tarsus length). In the observed nest, both parents participated similarly in feeding the chicks. The average frequency of feeding increased from about 5 per hour on the day of hatching to more than 20 per hour in the last days in the nest. G-test showed statistically significant differences between the male and the female in the distribution of average duration of visit ( G=52.3, df=10, P<0.05). During the first few days the female stayed at the nest longer than the male. After 6 days, average duration of a visit in the nest for both parents shortened to several seconds. [ABSTRACT FROM AUTHOR]

The mud crab Scylla serrata was collected from Ramisi river estuary for a period of 14 months (January 1990–February 1991) using madema traps. For each crab, the carapace width (mm), sex and weight were noted, and the number of ovigerous female crabs was recorded. Both ovigerous and non-ovigerous females were dissected in order to observe of the maturity stages of ovaries. The ovarian maturity stages were described as stage zero – virgin/resting, stage one – developing, stage two – well developed and stage thre e– ripe. The most abundant was stage two throughout the study period. The smallest ovigerous crab had a carapace width of 139 mm. A test of homogeneity of the binomial distribution of the sex ratio showed homoscedasticity (χ2 = 14.615; d.f. = 13; p> 0.05) and the overall sex ratio did not differ from 1:1 (χ2 = 0.776; d.f. = 1; p> 0.05). The variance test of homogeneity of the binomial distribution of sex in relation to size showed a very significant heterogeneity (χ2 = 32.83; d.f. = 9; p< 0.05). There was no significant difference when the overall mean sizes for males and females were compared using t-test (t = 4.26; d.f. = 18; p< 0.001). The relatively high numbers of females with stage two ovaries indicated that spawning took place throughout the year with a possible peak in the second half of the year. [ABSTRACT FROM AUTHOR]

In vertebrates, offspring have a relatively inefficient immune system soon after birth. Female birds transmit immunoglobulins to the egg, which can confer protection against parasites to their offspring after hatching, but allocation of immune factors can depend on the reproductive value of the offspring as affected, for example, by the quality of their father. We analyse the variation in immunoglobulin levels of female barn swallows (Hirundo rustica) during the breeding cycle in relation to the expression of a secondary sexual character of their mates. Circulating immunoglobulins peaked on approximately the day before that of laying of their first egg, but postlaying concentration was similar to the concentration well before laying. Immunoglobulin levels per unit volume of plasma were lower for females breeding late compared with those breeding early. Haematocrit of females reached an absolute minimum on the day of laying of the third egg. In males, concentration of immunoglobulins relative to other plasma proteins did not change in relation to the breeding stage. Smaller relative concentrations of immunoglobulins and haematocrit were observed in males breeding late in the season. Immunoglobulin concentration of females was positively correlated with the level of ornamentation of their mates. These results suggest that females alter their immune profile to transmit humoral factors providing immune defence against pathogens to their offspring after hatching. This enhancement of immune protection is larger when the offsprings are of relatively large reproductive value as when sired by high quality males. Alternatively, females with relatively large immunoglobulin concentration preferentially mate with the most ornamented males. [ABSTRACT FROM AUTHOR]

• Whole brain gal and prl 1 were examined using quantitative PCR in two cichlid species. • In both species caring males, but not females, had higher prl 1 and gal levels. • gal levels were highest when the need for parental defence was greatest. Our understanding of the hormonal mechanisms underlying parental care mainly stems from research on species with uniparental care. Far less is known about the physiological changes underlying motherhood and fatherhood in biparental caring species. Here, using two biparental caring cichlid species (Neolamprologus caudopunctatus and Neolamprologus pulcher), we explored the relative gene-expression levels of two genes implicated in the control of parental care, galanin (gal) and prolactin (prl). We investigated whole brain gene expression levels in both, male and female caring parents, as well as in non-caring individuals of both species. Caring males had higher prl and gal mRNA levels compared to caring females in both fish species. Expression of gal was highest when young were mobile and the need for parental defense was greatest and gal was lowest during the more stationary egg tending phase in N. caudopunctatus. The onset of parenthood was associated with lower expression of prl and higher expression of gal in N. pulcher , but this pattern was not observed in N. caudopunctatus. Our study demonstrates that gal gene expression is correlated with changes in parental care in two biparental cichlid species and extends both knowledge and taxonomic coverage of the possible neurogenetic mechanisms underlying parental care. [ABSTRACT FROM AUTHOR]

Flower induction methods—hormone application or exposure to physiological stress, or both—are used routinely for shortening breeding cycles and increasing seed production in white spruce (Picea glauca (Moench) Voss). The objectives of this study were: (1) to evaluate the effects of flower induction on seed yield and quality in white spruce; and (2) to determine if flower induction treatments affect the maternal contribution to offspring. We assessed the effects of flower induction treatments, which consisted of gibberellin A4/7 (GA4/7) and naphthaleneacetic acid (NAA) stem injections, on allele segregation for 28 clones, number of seeds per cone, number of sound seeds per cone, seed weight, and the germination rate of a subset of clones. Flower induction treatments did not affect any of the phenotypic traits examined. No increase in segregation distortion in allozyme loci following flower induction treatments was observed. [ABSTRACT FROM PUBLISHER]

Patterns of breeding cycle aggressive behavior were examined in colonies of domesticated zebra finches (Poephila guttata). Aggressive behaviors of zebra finch pairs were low during non-nesting periods but were maintained at high levels dining the three nesting periods: the incubating, hatching, and nestling periods. Defense of the nest site was the prominent functional category of aggression, followed by defense of individual distance. Defense of' mate, defense of young and defense of nesting material rarely occurred. Male and female members of pair bonds shared the duties of defense of' the nest site and parental care. During observation times males exhibited greater frequencies of aggressive actions throughout the breeding cycle and females spent a greater amount of time in the nest during the three nesting periods. The pattern and functional categories of aggressive behavior in the zebra finch colonies correspond most closely to the nest site defense hypothesis for the evolution of breeding season aggression. [ABSTRACT FROM AUTHOR]

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The seasonal condition ( K) and relative condition ( K ) cycles and their changes with the growth of the fish Chanda commersonii (Cuv. and Val.) for 2 yrs are presented. Better K is shown by the smaller immature and first maturity stages and larger, almost senile groups but they show a K factor below '1'. The actively breeding adults show a uniform fail in K but they give comparatively high K values (above '1'). These changes in K and K with the growth of the fish are clearly reflected in their seasonal cycles also. K cycle would thus appear to follow a pattern of build up and loss of body resources, indirectly following the breeding cycle while the K cycle follow the breeding and feeding cycles directly, as shown by their seasonal changes and changes with growth of the fish for 2 yrs. Since only minor deviations from unity occur in K factor it furnishes a more sensitive index of somatic difference between age groups, of breeding season and feeding cycle. [ABSTRACT FROM AUTHOR]

Daily injections of L-dihydroxyphenylalanine (L-DOPA, dopamine precursor) given 12 hour after 5-hydroxytryptophan (5-HTP, serotonin precursor) eliminated annual testicular regression in seasonally breeding sub-tropical Palm Squirrel that undergoes seasonal changes in responsiveness to day-length and humidity. Other temporal relations (L-DOPA given 0, 4, 8, 16 and 20 hours after 5-HTP administration) decreased/delayed the rate of regression and maintained the reproductive system at intermediate level. 12-hour-relation maintained full breeding condition (maximum gonad and accessory sex organs) unlike control, which exhibited complete atrophy of primary and accessory sex organs. It seems likely that these injections entrained the circadian serotonergic and dopaminergic oscillations and the interaction/phase relation of these two systems through their many circadian expressions (neural/hormonal) accounts for the seasonal interpretation of environmental factors. It is suggested that response in the present study is not a pharmacological effect of drugs but temporal synergism of neural acitivities affected the seasonality of reproduction as only 12-hour-relation of 5-HTP and L-DOPA maintained breeding activity during post reproductive phase of annual gonad cycle in Palm Squirrel. [ABSTRACT FROM AUTHOR]

The breeding of forest trees is only a few decades old, and is a much more complicated, longer, and expensive endeavor than the breeding of agricultural crops. One breeding cycle for forest trees can take 20–30 years. Recent advances in genomics and molecular biology have revolutionized traditional plant breeding based on visual phenotype assessment: the development of different types of molecular markers has made genotype selection possible. Marker-assisted breeding can significantly accelerate the breeding process, but this method has not been shown to be effective for selection of complex traits on forest trees. This new method of genomic selection is based on the analysis of all effects of quantitative trait loci (QTLs) using a large number of molecular markers distributed throughout the genome, which makes it possible to assess the genomic estimated breeding value (GEBV) of an individual. This approach is expected to be much more efficient for forest tree improvement than traditional breeding. Here, we review the current state of the art in the application of genomic selection in forest tree breeding and discuss different methods of genotyping and phenotyping. We also compare the accuracies of genomic prediction models and highlight the importance of a prior cost-benefit analysis before implementing genomic selection. Perspectives for the further development of this approach in forest breeding are also discussed: expanding the range of species and the list of valuable traits, the application of high-throughput phenotyping methods, and the possibility of using epigenetic variance to improve of forest trees. [ABSTRACT FROM AUTHOR]

The giant gourami Osphronemus goramy Lacépède, 1801, spontaneously spawns in captivity, making nests for egg deposition when suitable nest supports and nesting material are made available in rearing facilities. The seasonal variation in reproductive performance of the giant gourami was characterized during a 20-month experiment in two compartmentalized ponds (about 550 m2 each) at a fry production center in West Java, Indonesia. A total of 208 giant gourami broodfish were introduced in the two experimental ponds, with a sex-ratio of one male to three females in each of the 52 spawning compartments delimited by vertical nets. Nesting supports in each spawning compartment were examined every two days for the presence of eggs resulting from natural reproduction. Three performance indicators were quantified from the collected nests: spawning frequency (monthly number of spawns per female), effective fecundity (number of eggs per spawn) and egg quality (estimated from the proportion of clear living eggs in each spawn). The seasonality of giant gourami reproduction was analyzed as a function of seasonal variation in rainfall, rearing water temperature and day length. Based on a total of 413 collected spawns, the multiple linear regression models did not show any significant relationship between giant gourami spawning frequency and the three environmental variables studied. In contrast, the number of eggs per spawn was highly and positively related to rainfall (p <.0001), moderately and negatively related to water temperature (p <.001), and weaklier and negatively related to day length (p <.01). The proportion of clear eggs was positively related to day length (p <.01). Overall, this study represents one of the first comprehensive datasets on the reproductive phenology of giant gourami, and as such will be helpful in formulating broodfish management strategies for the species. • Seasonal fluctuations in the reproduction of giant gourami was assessed in Tasikmalaya ponds (West Java, Indonesia). • Reproduction was analyzed in relation to rainfall, rearing water temperature and day length. • Giant gourami reproduced all year long and spawning frequency was not related to the environmental parameters tested. • Number of eggs per spawn was strongly influenced by rainfall and to a lesser extent by water temperature and day length. • Egg quality was positively related to day length. [ABSTRACT FROM AUTHOR]

During the last decades plastic pollution has become a common issue in marine environments. Studies on seabirds have focused on species that ingest plastics mistaken for prey or indirectly through their preferred prey or, on how foraging strategy influences this behaviour. We evaluated plastic ingestion in relation to the proximity of nests to areas with different anthropogenic pressure, breeding status and breeding stage. We analyzed regurgitated pellets (n = 1001) from a seabird, the Brown Skua (Stercorarius antarcticus lonnbergi) at Esperanza/Hope Bay, Antarctic Peninsula. Plastics were found in 9% of pellets, only in breeders from an area with high antropogenic activity. The prevalence of plastic increased during the brooding of chicks stage, when skuas expand their feeding niche. Our results support previous work which demonstrated that seabirds with wider feeding niche show higher loads of plastics. Altogether, this provides insights into the dynamics of plastic transfer within the environment. • Anthropogenic activity is associated to the risk of plastic ingestion by seabirds. • Plastic remains were only found in pellets from skuas breeding in disturbed areas. • Debris was found in 9 % of samples from breeding skuas. • Plastic debris ocurrence frequency increased during the parental care stage. • Risk of plastic ingestion is influenced by the foraging niche breadth. [ABSTRACT FROM AUTHOR]

The hypothalamic neuropeptides arginine vasopressin (AVP) and oxytocin (OT) modulate social behavior across a wide variety of species. However, the role of arginine vasotocin (AVT) and isotocin (IT, the teleost homologs of AVP and OT) in regulating biparental care especially in the context of monogamy is not well studied. Here, using high-performance liquid chromatography (HPLC), we investigated how bioactive whole brain AVT and IT neuropeptide levels vary in relation to the phase of the breeding cycle and sex, in a monogamous biparental cichlid fish, Neolamprologus caudopunctatus. Since non-caring individuals of this species readily cannibalize eggs, but caring parents never do, we further investigated whether there might be changes in AVT/IT whole brain levels that correspond to the transition from a non-breeding, egg cannibal to an egg caring parent. We found that AVT levels were higher in females than in males and that AVT levels were highest when the need to defend the young was greatest. Breeding pairs that had a strong pair-bond and a higher frequency of nest care had the highest levels of AVT, whereas individuals that spent little time close to their breeding partner, displayed aggression towards their partner and neglected their nest duties (signs of a weak pair bond), had lower whole brain AVT levels. Isotocin (IT) levels did not differ between sexes and we did not detect any variation across the breeding cycle, with pair-bonding scores or with parental behavior. Our results show that whole brain AVT levels are linked to the breeding cycle, nest maintenance and pair-bonding score in this species. Furthermore, our study highlights species and sex-specific nonapeptides patterns in bi-parental caring fish and contributes to the increasing knowledge on neuroendocrinological mechanisms underlying parental care. • Bioactive vasotocin and isotocin whole brain levels were examined using HPLC in a monogamous, bi-parental cichlid fish. • AVT levels were higher in females than males. • AVT levels were highest when the need to care was greatest. • Nest maintenance was positively correlated with levels of whole brain AVT. [ABSTRACT FROM AUTHOR]

Soto Florencia Anabella, Grandi María Florencia, García Néstor Aníbal, Crespo Enrique Alberto, and Dans Silvana Laura (2017) Mass strandings represent a valuable source of information, especially when it comes to difficult-to-access pelagic species, such as Globicephala melas edwardii. We collected reproductive organs from 27 female pilot whales stranded in Caleta Malaspina, Chubut, Argentina. Our main objective was to analyze reproductive parameters of female long- finned pilot whales in the southern hemisphere. To achieve this, we studied age and reproductive status in order to approximate age and body length at sexual maturity, breeding interval, and fertility of this subspecies. The maturity state was determined by recording different ovulation bodies obtained from histological sections and by assessing the presence of milk in the mammary glands and a fetus, and we concluded that 5 of the females were immature and 22 were mature females. Finding mature females in different reproductive states (resting, in lactation, pregnant, or pregnant and in lactation) along with the great variety of fetus sizes would indicate that copulation and birth are not governed by seasonality. Age at sexual maturity was 8 years old and length at sexual maturity would reach 365.50 cm. The annual pregnancy rate was constant with age for mature females at 0.41 ovul / year, with a breeding interval of 2.4 years. The average fertility varied between 0.19 and 0.21. All the parameters are within the estimated range for females of the North Atlantic subpopulation, except for the breeding interval, which was significantly lower than estimates for the northern subspecies. This study could be limited because all individuals come from a single mass stranding. While this study allowed us to reach some conclusions about the reproductive biology of female G. melas edwardii in the Southwestern Atlantic Ocean, further studies are needed to fully comprehend the behavior and biology of this species.