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Seabirds have been touted as excellent bioindicators of mercury pollution. We utilised grey-faced petrel (Pterodroma gouldi) feathers to assess interannual differences in total mercury (THg) concentrations in adults (2020-2021) and chicks (2019-2021) breeding in the Auckland region of New Zealand. For adults, we also correlated feather THg with bird age (3-37+ years) and breeding outcome (i.e., Non breeder, Egg failed, Chick reared) recorded for that season i.e., 2020 and 2021. Interannual differences in chick feather THg were matched with bulk stable isotopes (δ 13 C, δ 15 N) to map the influence of adult foraging behaviour on chick feather THg values. Adult feather THg levels were similar across the years investigated i.e., mean ± S.D. 38.2 ± 12.8 (2020), and 39.5 ± 14.7 (2021) ug g -1 (some of the highest THg values recorded for seabirds). A slight, but significant decrease in THg accumulation was evident as age increased but feather THg had no significant influence on breeding outcome. Interannual differences in chick feather THg concentrations were 7.78 ± 1.6 (2019), 4.23 ± 1.45 (2020) and 6.97 ± 4.41 (2021) μg g -1 , (p < 0.01); and correlated with a significantly lower δ 13 C value i.e., -17.2 ± 0.4 ‰ (2019), -17.8 ± 0.3 ‰ (2020) and -17.6 ± 0.2 ‰ (2021). This suggests that the lower feather THg values in 2020 chicks resulted from more oceanic, rather than shelf-edge, prey being consumed by chicks that year. Values of δ 15 N in chick feathers remained consistent among years i.e., 15.2 ± 1.2 ‰ (2019), 15.2 ± 0.2 ‰ (2020) and 15.3 ‰ (± 0.4). Due to these interannual differences, we recommend using grey-faced petrel chicks to monitor Hg pollution over adults. Chicks are also subject to cultural harvests by Māori communities, offering partnership opportunities to generate mutually beneficial information streams for Māori communities and scientists alike., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Authors. Published by Elsevier B.V. All rights reserved.)

Many rare and endangered species are difficult to locate, observe, and study. Consequently, many individuals, breeding pairs, and even populations of such species could remain undetected. Genetic markers can potentially be used to detect the existence of undiscovered individuals and populations, and we propose a method to do so that requires 3 conditions. First, sampling of the known population(s) of the target species must be comprehensive. Second, the species must display a reasonable level of philopatry and genetic structuring. Third, individuals must be able to be caught outside of breeding locations (e.g., at courtship or feeding areas, in flight), and the level of recapture must be reasonably high. We applied our method to the Chatham Island Taiko (Pterodroma magentae), one of the world's most endangered seabirds. We sequenced the Taiko mitochondrial cytochrome b gene and both copies of a fragment of the duplicated domain I of the control region. Twenty-one haplotypes were revealed, including 4 (19%) not found in birds at known burrows. These results suggest there are more burrow groups yet to be located. The species is a pelagic gadfly petrel that inhabits land only in the breeding season during which it is nocturnal and nests in burrows. Taiko burrows are situated in dense forest in a remote area of Chatham Island, and are consequently difficult to locate and study. It is important that all Taiko burrows be discovered to enable monitoring and protection of the birds from exotic predators.

We report the results of the first field study examining seasonal changes in corticosterone responses of typically long-lived birds of the order Procellariiformes. In particular, we examined whether grey-faced petrels Pterodroma macroptera gouldi showed changes in circulating baseline corticosterone concentrations and corticosterone responses to a standardized handling protocol across the breeding season. Such changes have been associated with changes in body condition and variations in energy demands on adult birds through the breeding season. During early incubation, males were in significantly better condition than females that had just completed laying, whereas during late incubation, males were in significantly poorer condition than females. In spite of these differences, there was no significant difference in baseline corticosterone concentrations between sexes or among birds at different reproductive stages. However, we detected significant differences in corticosterone responses associated with a standardized handling protocol at different stages through the breeding season. Responses were significantly greater during incubation compared with the prelay period and late chick rearing. Body condition was weakly and negatively correlated with maximum and total integrated corticosterone level, indicating that some of the individual variability in stress corticosterone responses could be explained by variation in body condition. However, the largest stress response occurred during late incubation and was independent of sex, although males were in relatively poor condition and females in relatively good condition. This period coincided with the breeding stage in which energy constraints on individual adults were higher than at other periods of the reproductive cycle and birds may be physiologically primed for extended fasts.

Objective: To investigate the natural history and predictors of outcome of posthaemorrhagic ventriculomegaly in the very low birthweight (VLBW) infant., Methods: All VLBW infants admitted between September 1994 and September 1997 to the neonatal intensive care units of Brigham and Women's Hospital (Boston), Children's Hospital (Boston), and Christchurch Women's Hospital (New Zealand) with germinal matrix intraventricular haemorrhage (IVH) were identified. All charts and ultrasound scans were reviewed to define the natural history and perinatal and/or postnatal factors of value in prediction of the course of posthaemorrhagic ventriculomegaly. Progressive ventricular dilatation (PVD) was defined from the results of serial cranial ultrasound scans., Results: A total of 248 VLBW infants had evidence of IVH (22% of all VLBW infants, mean (SD) gestational age 26.8 (2.6) weeks). A quarter of the infants exhibited PVD. Spontaneous arrest of PVD occurred without treatment in 38% of infants with PVD. Of the remaining 62% with persistent PVD, 48% received non-surgical treatment only (pharmacological and/or drainage of cerebrospinal fluid by serial lumbar punctures), 34% received surgical treatment with insertion of a ventriculoperitoneal reservoir and/or shunt, and 18% died. The development of PVD after IVH and adverse short term outcome, such as the requirement for surgery, were predicted most strongly by the severity of IVH., Conclusions: These data reflect the natural history of PVD in the 1990s and show that, despite a slight reduction in its overall incidence, there appears to be a more aggressive course, with appreciable mortality and morbidity in the extremely premature infant. The major predictor of adverse short term outcome, defined as death or need for surgical intervention, was the severity of IVH. These findings may be valuable for the management of very small premature infants.