Influence of hand rearing and bird age on the fecal microbiota of the critically endangered kakapo.

The critically endangered New Zealand parrot, the kakapo, is subject to an intensive management regime aiming to maintain bird health and boost population size. Newly hatched kakapo chicks are subjected to human intervention and are frequently placed in captivity throughout their formative months. Hand rearing greatly reduces mortality among juveniles, but the potential long-term impact on the kakapo gut microbiota is uncertain. To track development of the kakapo gut microbiota, fecal samples from healthy, prefledged juvenile kakapos, as well as from unrelated adults, were analyzed by using 16S rRNA gene amplicon pyrosequencing. Following the original sampling, juvenile kakapos underwent a period of captivity, so further sampling during and after captivity aimed to elucidate the impact of captivity on the juvenile gut microbiota. Variation in the fecal microbiota over a year was also investigated, with resampling of the original juvenile population. Amplicon pyrosequencing revealed a juvenile fecal microbiota enriched with particular lactic acid bacteria compared to the microbiota of adults, although the overall community structure did not differ significantly among kakapos of different ages. The abundance of key operational taxonomic units (OTUs) was correlated with antibiotic treatment and captivity, although the importance of these factors could not be proven unequivocally within the bounds of this study. Finally, the microbial community structure of juvenile and adult kakapos changed over time, reinforcing the need for continual monitoring of the microbiota as part of regular health screening.

Inheritance of telomere length in a bird.

Telomere dynamics are intensively studied in human ageing research and epidemiology, with many correlations reported between telomere length and age-related diseases, cancer and death. While telomere length is influenced by environmental factors there is also good evidence for a strong heritable component. In human, the mode of telomere length inheritance appears to be paternal and telomere length differs between sexes, with females having longer telomeres than males. Genetic factors, e.g. sex chromosomal inactivation, and non-genetic factors, e.g. antioxidant properties of oestrogen, have been suggested as possible explanations for these sex-specific telomere inheritance and telomere length differences. To test the influence of sex chromosomes on telomere length, we investigated inheritance and sex-specificity of telomere length in a bird species, the kakapo (Strigops habroptilus), in which females are the heterogametic sex (ZW) and males are the homogametic (ZZ) sex. We found that, contrary to findings in humans, telomere length was maternally inherited and also longer in males. These results argue against an effect of sex hormones on telomere length and suggest that factors associated with heterogamy may play a role in telomere inheritance and sex-specific differences in telomere length.

Thirty polymorphic microsatellite loci from the critically endangered kakapo (Strigops habroptilus).

Thirty polymorphic microsatellite loci were developed from the critically endangered kakapo (Strigops habroptilus), using an enriched genomic library. Characterization of loci using 90 kakapo revealed an average of 3.3 alleles per locus (range: 2-5) and an average expected heterozygosity of 0.47 (range: 0.17-0.70). The probability of identity (7.2 × 10(-15) ) and probability of exclusion (0.999999) demonstrate that these loci are a highly informative marker set that can aid the genetic management of the kakapo.

Sex allocation theory aids species conservation.

Supplementary feeding is often a key tool in the intensive management of captive and threatened species. Although it can increase such parameters as breeding frequency and individual survival, supplementary feeding may produce undesirable side effects that increase overall extinction risk. Recent attempts to increase breeding frequency and success in the kakapo Strigops habroptilus using supplementary feeding inadvertently resulted in highly male-biased chick sex ratios. Here, we describe how the inclusion of sex allocation theory has remedied this conservation dilemma. Our study is the first to manipulate chick sex ratios in an endangered species by altering maternal condition and highlights the importance of incorporating evolutionary theory into modern conservation practice.