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Identifying the composition of avian diets is a critical step in characterizing the roles of birds within ecosystems. However, because birds are a diverse taxonomic group with equally diverse dietary habits, gaining an accurate and thorough understanding of avian diet can be difficult. In addition to overcoming the inherent difficulties of studying birds, the field is advancing rapidly, and researchers are challenged with a myriad of methods to study avian diet, a task that has only become more difficult with the introduction of laboratory techniques to dietary studies. Because methodology drives inference, it is important that researchers are aware of the capabilities and limitations of each method to ensure the results of their study are interpreted correctly. However, few reviews exist which detail each of the traditional and laboratory techniques used in dietary studies, with even fewer framing these methods through a bird-specific lens. Here, we discuss the strengths and limitations of morphological prey identification, DNA-based techniques, stable isotope analysis, and the tracing of dietary biomolecules throughout food webs. We identify areas of improvement for each method, provide instances in which the combination of techniques can yield the most comprehensive findings, introduce potential avenues for combining results from each technique within a unified framework, and present recommendations for the future focus of avian dietary research.

Tourette syndrome (TS) is a neurodevelopmental disorder characterised by involuntary, repetitive and non-rhythmic motor and vocal tics. Despite suggestion that diet may affect tics, and the substantial research into children's diet, eating behaviours and sensory processing in comorbid disorders (e.g. ASD), research in TS is lacking. The present study examined differences between children with and without TS in parental reports of child selective eating, food preferences and sensitivity, and aimed to examine sensory sensitivity as a predictor of food selectivity outcomes in children with and without TS. Thirty caregivers of children with TS (M = 10 years 8 months [SD = 2.40]) and the caregivers of 30 age- and sex-matched typically developing (TD) children (M = 9 years 9 months [SD = 2.50]) completed the following measures online: Short Sensory Profile, Food Preference Questionnaire for Children, Child Eating Behaviour Questionnaire. Children with TS were reported to have significantly higher levels of food selectivity and sensory sensitivity, and less preference for fruit and vegetables than TD children. Importantly, while higher levels of overall sensory sensitivity predicted eating outcomes in the TS group, only sensitivity to taste/smell was found to be a predictor of food selectivity and preference for vegetables for both groups of children. The findings suggest that efforts to address food selectivity in children with TS may be enhanced by including strategies that address atypical sensory processing.

Background Being an empathetic researcher can be crucial in understanding participants' perspectives. However, while the need for empathy is recognised in qualitative interview research, there is less acknowledgement of its value with other methods of collecting data. Researchers can face various challenges when the instruments and approaches used to collect data are new to them. The value of researchers acting as participants when undertaking pre-pilot work are not be underestimated. Aim To provide a reflective account of the pre-pilot work undertaken by the authors before their main study. Discussion Pre-pilot work that involves the researchers as participants can develop cultural competence, as well as empathetic insight into participants' perspectives, thus enabling them to refine and strengthen their main study. Conclusion It takes time when planning research to incorporate appropriate pre-pilot work that assists personal training and learning. However, this can pay dividends in terms of the empathetic insight gained for the refinement of the proposed study. Pre-pilot work and a reflective approach can strengthen rigour, as well as assist in planning research and collecting data. Implications for practice Experienced researchers may be novices at using specific tools or methods of collecting data. Pre-pilot work enables a greater understanding and deeper appreciation of participants' perspectives.

Interspecific nest-site competition among secondary cavity nesters can lead to nest-takeover events resulting in mixed broods. The nestlings of the smaller species in these mixed broods are usually unsuccessful. Among multiple takeover events occurring over 33 years of nest-monitoring records, we report 4 accounts of Protonotaria citrea (Prothonotary Warbler) fledging from mixed broods after Tachycineta bicolor (Tree Swallow) displaced Warblers from active nests. In each case, Prothonotary Warblers hatched earlier than their Tree Swallow nestmates, reducing the size discrepancy between species and enabling these nestlings to survive.

Bergmann’s rule is a well‐established, ecogeographical principle that states that body size varies positively with latitude, reflecting the thermoregulatory benefits of larger bodies as temperatures decline. However, this principle does not seem to easily apply to migratory species that are able to avoid the extreme temperatures during winter at higher latitudes. Further, little is known about the ontogeny of this relationship across life stages or how it is influenced by ongoing global climate change. To address these knowledge gaps, we assessed the contemporary relationship between latitude and body size in a long‐distance migratory species, the prothonotary warbler (Protonotaria citrea) across life stages (egg to adult) on their breeding grounds. We also measured historic eggs (1865‐1961) to assess if the relationship between latitude and size during this life stage has changed over time. In accordance with Bergmann’s rule, we found a positive relationship between latitude and body mass during all post‐embryonic life stages, from early nestling stage through adulthood. We observed this same predicted pattern with historic eggs, but contemporary eggs exhibited the reverse (negative) relationship. We suggest that these results indicate a genetic component to this pattern and speculate that selection for larger body size in altricial nestlings as latitude increases may possibly drive the pattern in migratory species as even rare extreme cold weather events may cause mortality during early life stages. Furthermore, the opposite relationships observed in eggs, dependent on time period, may be related to the rapidly warming environments of higher latitudes that is associated with climate change. Although it is unclear what mechanism(s) would allow for this recent reversal in eggs (but still allow for its maintenance in later life stages). This evidence of a reversal suggests that anthropogenic climate change may be in the process of altering one of the longest‐standing principles in ecology., Following Bergmann's rule, a positive relationship existed between latitude and body mass during all post‐embryonic developmental stages in a long‐distance migratory bird species, the prothonotary warbler (Protonotaria citrea). As this pattern appeared during the first days posthatching, these data suggest that the benefits of larger body size in colder environments may accumulate at an early age in altricial migratory species and may support the hypothesis of a genetic component underlying this pattern.

Feeding problems are common, with implications for nutrition, growth and family stress, placing burden on primary care services. The Montreal Children's Hospital Feeding Scale (MCHFS) is a quick and reliable measure of feeding problems for clinical settings, but there is little examination of its relationship to commonly used research measures of parental feeding practice, child eating behaviour and observations of parent-infant interaction at mealtimes. We examined the relationships between the MCHFS, demographics and early feeding history, weight across the first year, parental report of feeding practices and child eating behaviours, and observations of maternal-infant feeding interaction at 1 year. The MCHFS, Comprehensive Feeding Practices Questionnaire (CFPQ) and Child Eating Behaviour Questionnaire (CEBQ) were completed by 69 mothers when their infants were 1-year-old (37 male, 32 female). Infant weight was measured at 1 week, 1 month, 6 months and 1 year. Mothers were observed feeding their infants at 1 year. The MCHFS was reliable (Cronbach's alpha = .90) and showed significant overlap with other measures of feeding and eating. Potential feeding problems were identified in 10 of the children (14%) reflecting similar rates in other community samples. Higher MCHFS scores were associated with lower birthweight and weight across the first year, greater satiety responsiveness, fussiness and slowness in eating, lower enjoyment of food and food responsiveness, and less observed infant food acceptance. Parents of infants with more feeding problems reported less encouragement of balance and variety in their children's diets. Conclusion: MCHFS showed good criterion validity with other parental report measures of eating and observations of mealtime interactions. MCHFS may be a useful tool for researching feeding problems in community samples.

Anecdotal reports frequently suggest some dietary involvement in the maintenance of tics in children with Tourette syndrome (TS). This scoping review aimed to (1) understand the possible influence of diet as a trigger of tics and (2) map out the existing studies documenting dietary interventions in children with TS. Current evidence suggests no single diet to benefit individuals with TS. However, reports from parents of children with TS suggest that certain allergens in food may exacerbate tic-related symptoms. For example, an increase in tics has been related to the consumption of caffeine and refined sugar. Moreover, oligoantigenic diets and sugar-free diets have been identified as significantly reducing tics. More research is urgently needed to develop more accurate guidance for parents and children with TS, as many have reported using dietary and nutritional supplements, despite the lack of evidence detailing any benefits, side effects and recommended doses.

Heightened sensitivity to sensory information has been associated with food fussiness in both atypical and typical development. Despite food fussiness and sensory dysfunction being reported as common concerns for children with neurodevelopmental disorders, the relationship that exists between them, and whether they differ between disorders, has yet to be established. The current study aimed to examine sensory sensitivity as a predictor of food fussiness in three different neurodevelopmental disorders, whilst controlling for comorbidity amongst these disorders. Ninety-eight caregivers of children with Attention Deficit Hyperactivity Disorder (ADHD; n = 17), Tourette Syndrome (TS; n = 27), Autism Spectrum Disorder (ASD; n = 27), and typical development (TD; n = 27) were compared using parental reports of child food fussiness, food preferences and sensory sensitivity. Children with neurodevelopmental disorders were reported to have significantly higher levels of both food fussiness and sensory sensitivity, with children with ASD and TS also showing significantly less preference for fruit than children with TD. Importantly, higher levels of taste/smell sensitivity predicted food fussiness for all four groups of children. In addition, taste/smell sensitivity fully mediated the differences in food fussiness between each group of neurodevelopmental disorders compared to the TD group. The findings highlight that food fussiness is similar across these neurodevelopmental disorders despite accounting for comorbidity, and that greater sensitivity to taste/smell may explain why children with neurodevelopmental disorders are more likely to be fussy eaters.

Despite guidance from the World Health Organization and the U.K. Department of Health, many mothers introduce solid food before their infant is 6 months old. The current study aimed to investigate relationships between maternal feeding behaviours (preintroduction and postintroduction to solids), infant temperament, and the timing of introduction to solid food. Eighty‐one women were recruited on low‐risk maternity units and were contacted at 1 week, 3, and 6 months postpartum. Mothers of infants (45 males, 36 females, mean birth weight 3.52 kg [SD 0.39]) completed the behaviours component of the Infant Feeding Style Questionnaire via telephone interview at 3 months. At 6 months, they were observed feeding their infant solid food at home and reported infant temperament using the Infant Behaviour Questionnaire‐Revised (short form). Partial correlations (covariates: birth weight, maternal age, breastfeeding duration, and postnatal depression) revealed negative associations between age of introduction to solid food and temperament (smiling and laughter) and laissez‐faire milk feeding behaviours; and positive associations between age of introduction to solid food and restrictive milk feeding behaviours and verbal involvement during an observed mealtime. Hierarchical multiple regression analysis revealed that an infant's birth weight and the degree to which their mothers perceive them to smile and laugh are key predictors of when they will be introduced to solid food, over and above other variables of interest (e.g., maternal milk feeding behaviours, breastfeeding duration, and postnatal depression).

Prescribed burning maintains marsh habitat, but its impact on breeding King Rails (Rallus elegans) is poorly understood. This practice may serve as a means to enhance populations of a species whose numbers are declining in the southeastern United States. We used call-broadcast surveys and nest searches to categorize the state of occupied plots by the presence or non-presence of nesting activity in the Back Bay region, North Carolina and Virginia, in 2010. We also used nest video surveillance to estimate nest survival in 2009 and 2010. The probabilities that a surveyed plot was occupied (1) and contained an active nest (2) were higher in recently burned marsh plots (0–1 year-since-burn [YSB]) than in plots with ≥2 YSB at Mackay Island and Back Bay National Wildlife Refuges (NWRs). Highest probabilities were recorded in 0–1 YSB plots at Mackay Island NWR ( = 0.96 ± 0.04, = 0.75 ± 0.18), and the lowest in ≥2 YSB plots at Back Bay NWR ( = 0.21 ± 0.10, = 0.03 ± 0.04). Nest survival from egg laying to hatching (31 d) was 0.48 (95% confidence interval [CI] = 0.06–0.83), with an estimated 0.79 (95% CI = 0.29–0.96) survival rate for the incubation stage (21 d). These nest survival estimates for King Rails in fire-managed marshes were similar to estimates for other populations. Measures of vegetation cover, proxies for concealment, did not differ between nest sites and unused sites, even within recently burned marshes. This lack of differences in vegetation structure suggests that regrowth occurs rapidly during the period between burning (winter months) and the onset of reproduction (late April). Thus, recently burned marshes may benefit nesting King Rails by providing nest concealment. In addition, burned marshes may enhance availability of many invertebrates. Although we found that the probability that surveyed plots contained active nests was higher in recently burned marsh plots, estimates of fledging success are needed before marsh burns can be considered an effective means of fostering population growth. RESUMEN Ocurrencia de nidos y supervivencia del Rascon real en pantanos costeros con manejo de fuego en Carolina del Norte y Virginia Los incendios controlados ayudan a mantener los pantanos, pero su impacto en la reproduccion del Rascon real (Rallus elegans) esta poco estudiado. Esta practica puede servir como un medio de incrementar poblaciones de una especie cuyos numeros han declinado en el sudeste de Estados Unidos. Usamos censos con playback y busqueda de nidos a fin de categorizar el estado de ocupacion de parcelas por la presencia o ausencia de actividad de nido en la region de Back Bay, en Carolina del Norte y Virginia, en 2010. Utilizamos tambien monitoreo por video de nidos para estimar la supervivencia de nido en 2009 y 2010. Las probabilidades de que una parcela censada se encontrara ocupado () y de que contuviese nidos activos () fueron mas altos en pantanos recientemente incendiados (0–1 anos desde quema [ADQ]) que en parcelas con ≥2 ADQ en Isla Mackay y en el Refugio Nacional de Vida Silvestre (RNVS) de Back Bay. Las probabilidades mas altas fueron registradas en parcelas con 0–1 ADQ en Isla Mackay Island RNVS ( = 0.96 ± 0.04, = 0.75 ± 0.18), y la mas baja en parcelas con ADQ ⩾2 en Back Bay RNVS ( = 0.21 ± 0.10, = 0.03 ± 0.04). La supervivencia de nido desde la puesto de huevos hasta la eclosion (31 dias) fue de 0.48 (95% IC = 0.06–0.83), con un estimado de 0.79 (95% IC = 0.29–0.96) para la tasa de supervivencia para el estadio de incubacion (21 dias). Estos estimados para la supervivencia de nidos para el Rascon real en pantanos con manejo del fuego controlados fueron similares a los estimados para otras poblaciones. Las medidas de cubertura vegetal, representantes de camuflaje, no difirieron entre las parcelas con nidos y las parcelas sin nidos, aun dentro de pantanos recientemente quemados. Esta falta de diferencias en la estructura de la vegetacion sugiere que el crecimiento de la vegetacion ocurre rapidamente en el periodo entre la quema (meses de invierno) y el inicio de la temporada reproductiva (fines de Abril). Asi, pantanos recientemente quemados podrian beneficiar a la nidada del Rascon real al proveer camuflaje para el nido. Adicionalmente, los pantanos quemados podrian aumentar la disponibilidad de muchos invertebrados. Aun cuando encontramos que la probabilidad de que las parcelas censadas contuviesen nidos activos era mayor en parcelas recientemente quemadas, estimaciones del exito de los volantones son necesarias antes de que la quema en pantanos pueda ser considerada como un medio efectivo de estimular el crecimiento poblacional.

Curbing the declining trends of King Rails (Rallus elegans) that occupy freshwater emergent marshes requires an understanding of their ecology and response to management practices. King Rails were surveyed during the breeding season (March-June) at Back Bay and Mackay Island National Wildlife Refuges, Virginia and North Carolina, in 2009 and 2010. Twenty-two plots were surveyed in 2009 and 41 in 2010. Annual occupancy estimates were based on pooled data encompassing both refuges. In 2010, occupancy and abundance of King Rails were also estimated for each refuge and assessed with respect to fire management. Plots in 2010 were classified as recently burned (0–1 years-since-burn [YSB]) or ≥ 2 YSB. Occupancy probability was similar between 2009 (0.68 ± 0.14) and 2010 (0.62 ± 0.08). In 2010, occupancy probability was higher at Mackay Island (0.95 ± 0.06) than Back Bay (0.69 ± 0.13). Mean plot abundance (Mackay Island = 1.47 ± 0.38; Back Bay = 0.66 ± 0.22) was also higher. The probability of occupying...

Research examining the relationship between breastfeeding and infant weight has generated conflicting results. Few studies account for significant covariates and many suffer methodological problems such as retrospective self-report. The current study aimed to investigate relationships between breastfeeding duration, infant weight and eating and positive maternal mealtime behaviours, whilst overcoming many of the limitations of previous research. Eighty-one women on low-risk maternity units gave informed consent and were visited at home at 1-week, 1-, 6- and 12-months postpartum. Infants included 45 males and 36 females (mean birth-weight 3.52 kg [SD 0.39]). Mothers and infants were weighed and measured and feeding information was recorded at each visit. Infant weight was converted to a standard deviation score (SDS), accounting for age and sex. Mothers reported infant eating behaviours at 12-months using the Children's Eating Behaviour Questionnaire and were observed feeding their infants solid food at home at 6- and 12-months. Partial correlations (covariates: maternal age, education, BMI, smoking during pregnancy, household income, infant birth weight SDS and age introduced to solid foods) revealed negative associations between breastfeeding duration and 1- to 6- and 1- to 12-month weight gain, and 6- and 12-month weight. Breastfeeding duration was also associated with a slower rate of infant eating and greater observed maternal vocalisations, appropriateness and sensitivity. Results support a dose-response relationship between breastfeeding and infant weight and suggest that breastfeeding may encourage the development of obesity-protective eating behaviours through learning to attend to internal hunger and satiety signals. Future research should investigate whether relationships between slowness in eating and weight extend to satiety responsiveness after infancy.

Background and Objectives Postnatal depression correlates with postpartum weight retention, and dysregulated cortisol metabolism is evident in depressed individuals. Cortisol metabolism, BMI and metabolic phenotype are robustly associated but the role of cortisol metabolism in postnatal mental health and weight loss has never been examined. Design A longitudinal observation. Patients 49 healthy women with uncomplicated pregnancy. Measurements BMI and urinary steroid metabolites at 1 week and 1, 3, 6 and 12 months postpartum. Validated urinary steroid metabolite ratios were measured to determine the activities of 11β-hydroxysteroid dehydrogenases (11β-HSD) that interconvert inactive cortisone and active cortisol and the 5α-reductases that clear cortisol to its inactive metabolites. Postnatal depression symptoms were measured at 1, 6 and 12 months. Results Low 5α-reductase activity was associated with greater weight loss across the first year, independent of demographics, breastfeeding and depression. Postpartum BMI change was unrelated to postnatal depression at any time. Symptoms of postnatal depression were related to higher cortisol metabolite production at 12 months, independent of demographics and breastfeeding. Conclusions Greatest weight loss in the postpartum year was associated with lower conversion of cortisone to cortisol and lower conversion of cortisol to its metabolites, supporting previous work that demonstrates the facilitative role of lower 5α-reductase and 11β-HSD-1 in weight loss. Greater depression symptoms were associated with higher cortisol metabolite production rates. Whilst weight and mental health are both associated with dysregulation of the HPA axis, there may be different pathways towards depressed and obese phenotypes in healthy postpartum samples.

Integrative multiomics analyses of adipose and muscle tissue transcripts, S, and genotypes revealed novel genetic regulatory mechanisms of insulin resistance in African Americans.

Context: Low birth weight is associated with adverse metabolic outcome in adulthood. Exposure to glucocorticoid (GC) excess in utero is associated with decreased birth weight, but the prospective longitudinal relationship between GC metabolism and growth has not been examined. Objective: We have hypothesized that changes in GC metabolism leading to increased availability may impair growth. Design: This was a prospective, longitudinal study with clinical measurements and 24-hour urinary steroid metabolite analysis at 1, 4, 12, 26, and 52 weeks after delivery in mothers and their babies. Setting: The study was conducted with observations and samples collected in the volunteers' own homes. Participants: Healthy mothers and newborn babies/infants participated in the study. Interventions: There were no interventions. Main outcome measures: Urinary steroid metabolite excretion quantified by gas chromatography/mass spectroscopy across the first year of life in relation to change in weight was measured. Results: The total production of the GC metabolites quantified increased across the first year of life. Markers of 11β-hydroxysteroid dehydrogenase type 1 activity increased from the age of 3 months as did those of 5α-reductase activity. After correcting for confounding variables, low markers of 11β-hydroxysteroid dehydrogenase type 2 activity was associated with reduced absolute weight and decreased weight gain over the first year of life. In the mothers, 5α-reductase activity was low at birth and progressively increased to normal over the first 6 months postpartum. Conclusions: Increased GC exposure as a consequence of reduced 11β-hydroxysteroid dehydrogenase type 2 activity is likely to be a critical determinant of growth in early life. This not only highlights the central role of GCs and their metabolism, but also emphasizes the need for detailed longitudinal analyses.

Breastfeeding has a protective effect on obesity. Little is known about the mechanisms involved. Breast-milk contains cortisol, which is involved in appetite regulation (Wolkowitz, Epel, & Rues, 2001)[[Au: The references “Wolkowitz, Epel, and Rues, (2001) and Epel et al. (2001)” are cited in the text but not listed. Please check.]] and energy balance (Epel et al., 2001). This study is the first to investigate the role of breastfeeding and cortisol metabolism on weight-gain throughout the first year. It was hypothesised that breastfed infants would be lighter than formula-fed infants and that there would be a difference in their cortisol metabolism. Sixty-one infants (33 males, 28 females) and their mothers (mean age 30.0 years [SD 6.0]) were tested at 1-week, 1-, 3- and 6-months postpartum. Maternal and infant weights and feeding method were measured. Single urine samples from mothers and 24-h nappy collections were taken for cortisol metabolism analysis. ANCOVAs examining differences in infant weight showed at 1-week, there were no significant differences in weight F (2, 70) = 1.32, p = 0.27. At 1-month F (2, 65) = 3.31, p F (2, 48) = 4.10, p t (65) = −1.3, p = 0.05 and 6-months, t (48) = −2.09, p F (4, 2) = 21.31, p λ = 0.001 in steroid ratio UFF/UFE (indicative of higher cortisol) F (2, 2) = 86.99, p = 0.01. Breastfed infants have higher levels of UFF/UFE than formula-fed and mixed-fed infants ( p