Biology subjects

Ketaloya, S.

Publications and source records attributed to Ketaloya, S..

5 recordsLinked to original sources

bioRxiv2024

Lost to science for 126 years: Indigenous Knowledge and Camera Trapping Document the Critically Endangered Black-Naped Pheasant-Pigeon Otidiphaps insularis

We combined questionnaires collecting local ecological knowledge with passive and directed camera trapping and bird surveys to scientifically document the Black-Naped Pheasant-Pigeon Otidiphaps insularis for the first time since 1896. This species is endemic to Fergusson Island, in eastern Papua New Guinea, and is New Guineas most endangered terrestrial bird species. Indigenous subsistence-based hunters who participated in this research as informants had high levels of local bird knowledge and helped direct camera trapping for one of two successful camera trap captures. Local participants also shared traditional ecological knowledge about the Black-Naped Pheasant-Pigeon, including legends, chants, and a local name for this taxon, Auwo. The scarcity of observations over the course of a month-long expedition, its obscurity to the majority of local respondents interviewed, and prevalent threats from habitat destruction and introduced alien species further support its current Red List status (CR). Our results provide a case study for leveraging local ecological knowledge in combination with standardized survey techniques and may be an especially effective strategy for determining the status of other undocumented or data-deficient species in the southwest Pacific.

ecology↗

bioRxiv2024

An ornithological survey of Fergusson Island, D'Entrecasteaux Archipelago, Papua New Guinea, reveals new island records and noteworthy natural history observations

Fergusson Island lies off the southeastern end of New Guinea and is the largest landmass in the DEntrecasteaux and Trobriand Island Endemic Bird Area. We conducted audiovisual and camera trapping surveys in eastern Fergusson in September 2022 and recorded 97 bird species, documenting breeding and vocalizations for several of the EBAs endemic taxa. Notably, we provide the first confirmed documentation of the "lost" insularis subspecies of Pheasant Pigeon Otidiphaps nobilis (often recognized as a distinct species, Black-naped Pheasant-pigeon), in 126 years, observations of eight bird species not previously recorded from Fergusson, and nesting of Goldies Bird-of-Paradise Paradisea decora and the endemic crookshanki taxon of Capped White-eye Zosterops fuscicapilla (or Oya Tabu White-eye). Our new distributional records were mostly either migratory species or species found in open habitats, highlighting the value of surveying across seasons and habitats. We summarise our results and provide comments on distributional records, breeding behaviour, and vocalizations.

ecology↗

bioRxiv2023

Impacts of mate quality on female intrasexual aggression in two sister Malurus fairywren species

In a large and ever-growing number of animal species, it is now appreciated that females use colors as a visual signal in a range of social interactions, including both courtship and territorial aggression. Yet, it remains unclear whether female color phenotypes and/or aggressive behaviors are correlated with any attributes of their mates phenotype. For example, we might expect species in which males contribute more to parental care or territorial defense to have more colorful or aggressive females. On the other hand, within species, we might expect those females mated to higher quality males to be more colorful or aggressive than those mated to lower quality males. To begin to address these possibilities, we conducted a preliminary study in two sister taxa of fairywren (Maluridae) with distinct life-history strategies and plumage dichromatism: white-shouldered fairywrens (Malurus alboscapulatus moretoni) in tropical Papua New Guinea, a species in which both males and females have ornamented plumage and jointly defend territories year-round, and red-backed fairywrens (M. melanocephalus melanocephalus) in temperate Australia, a sexually dichromatic species with ornamented males and unornamented females. At the between species level, we predicted white-shouldered fairywren females would be more aggressive in same-sex interactions than red-backed fairywrens, as both white-shouldered males contribute to year-round territorial defense, whereas territories break-down during non-breeding in red-backed fairywrens. Further, we predicted that, within species, females mated to males of higher quality would be more aggressive in simulated same-sex encounters. Between species, female white-shouldered fairywrens were more aggressive on average than female red-backed fairywrens as predicted. Within both species, indices of male quality were not related to female aggression (although there was a non-significant tendency for more aggressive female white-shouldered fairywren to have heavier mates with longer tails). These results point to a need for additional research exploring relationships between life history, female plumage, and female aggressive behaviors in a wider range of species.

ecology↗

bioRxiv2023

Does capacity to elevate androgens underlie variation in female ornamentation and territoriality in White-shouldered Fairywren (Malurus alboscapulatus)?

Historic bias toward study of male sex hormones and sexual signals currently constrains our perspective of hormone--behavior--phenotype relationships. Resolving how ornamented female phenotypes evolve is particularly important for understanding the diversity of social signals across taxa. Studies of both males and females in taxa with variable female phenotypes are needed to establish whether sexes share mechanisms underlying expression of signaling phenotypes and behavior. White-shouldered Fairywren (Malurus alboscapulatus) subspecies vary in female ornamentation, baseline circulating androgens, and response to territorial intrusion. The moretoni ornamented female subspecies show higher female, but lower male androgens, and a stronger pair territorial response relative to pairs from the lorentzi unornamented female subspecies. Here we address whether subspecific differences in female ornamentation, baseline androgens, and pair territoriality are associated with ability to elevate androgens following gonadotropin releasing hormone (GnRH) challenge and in response to simulated territorial intrusion. We find that subspecies do not differ in their capacity to circulate androgens in either sex following GnRH or territorial intrusion challenges. Whereas pre-GnRH androgens were somewhat predictive of degree of response to territorial intrusions, higher androgens were associated with lower territorial aggression. Post-GnRH androgens were not predictive of response to simulated intruders, nor did females sampled during intrusion elevate androgens relative to flushed controls, suggesting that increased androgens are not necessary for the expression of territorial defense behaviors. Collectively, our results suggest that capacity to produce and circulate androgens does not underlie subspecific patterns of female ornamentation, territoriality, and baseline androgens.

animal behavior and cognition↗

bioRxiv2021

Male White-shouldered Fairywrens (Malurus alboscapulatus) elevate testosterone when courting females but not during territorial challenges

Testosterone mediates suites of physical and behavioral traits across vertebrates, and circulation varies considerably across and within taxa. However, an understanding of the causal factors of variation in circulating testosterone has proven difficult despite decades of research. According to the challenge hypothesis, agonistic interactions between males immediately prior to the breeding season produce the highest levels of testosterone measured during this period. While many studies have provided support for this hypothesis, most species do not respond to male-male competition by elevating testosterone. As a result, a recent revision of the hypothesis ( challenge hypothesis 2.0) places male-female interactions as the primary cause of rapid elevations in testosterone circulation in male vertebrates. Here, we offer a test of both iterations of the challenge hypothesis in a tropical bird species. We first illustrate that male White-shouldered Fairywrens (Malurus alboscapulatus) differ by subspecies in plasma testosterone concentrations. Then we use a social network approach to find that males of the subspecies with higher testosterone are characterized by greater social interaction scores, including more time aggregating to perform sexual displays. Next, we use a controlled experiment to test whether males respond to simulated territorial intrusion or courtship interaction contexts by elevating testosterone. Males sampled during courtship had greater plasma testosterone both relative to flushed controls and males sampled during simulated intrusion. Ultimately, our results are consistent with challenge hypothesis 2.0, as males rapidly elevated testosterone following interactions with females, but not during territorial challenges.

animal behavior and cognition↗