Aim To test the Eltonian noise hypothesis (ENH), that biotic interactions do not affect species distributions at large geographical scales.Location The Brazilian cerrado, a central South American savanna and biodiversity hotspot. MethodsWe modelled the distributions of 11 species of cerrado parrots using the software Maxent at four different spatial resolutions. We built models using abiotic variables, biotic variables (distribution of diet resources) and models combining abiotic and biotic variables. We compared model performance using the area under the curve of the receiver operating characteristic (AUC), retrieved from test data. We partitioned the variance between sets of predictors using a generalized linear model (GLM). Finally, we evaluated whether improvement in model performance (higher AUC values) in models with both abiotic and biotic variables, was related to the species' dietary niche breadth and/or spatial resolution of the models.Results We found that model performance was improved in most cases by the addition of biotic variables. Our variance-partitioning approach revealed that abiotic and biotic variables contribute independently to the final model. We found no relationship between model improvement and spatial resolution. We also found no relationship between dietary niche breadth and model improvement, indicating that dietary generalist and specialist species were not differently affected by the inclusion of biotic variables in the models. Main conclusionsOur results did not support the ENH. In this study, we explicitly incorporated a biotic variable (diet resource distribution) into species distribution models (SDMs), and we showed that these variables generally improve models and have independent contributions. These results agree with previous studies that incorporated biotic variables into SDMs. Ultimately, our results indicate that SDMs performed with abiotic variables only may depict only a partial representation of the geographical distribution of a species.

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The genus Brachycephalus Fitzinger, 1826 comprises 17 tiny species, eight of which were described only in the past 10 years (Frost 2012). Vocal communication is still poorly studied in this group, and despite its importance for taxonomic studies (e.g. Padial & De La Riva 2009) only two species of the group have had their calls described (Pombal et al. 1994; Verdade et al. 2008).

The continued loss, fragmentation, and degradation of forest habitats are driving an extinction crisis for tropical and subtropical bird species. This loss is particularly acute in the Atlantic Forest of South America, where it is unclear whether several endemic bird species are extinct or extant. We collate and model spatiotemporal distributional data for one such “lost” species, the Purple-winged Ground Dove Paraclaravis geoffroyi, a Critically Endangered endemic of the Atlantic Forest biome, which is nomadic and apparently dependent on masting bamboo stands. We compared its patterns of occurrence with that of a rare “control” forest pigeon, the Violaceous Quail-Dove Geotrygon violacea, which occurs in regional sympatry. We also solicit information from aviculturists who formerly kept the species. We find that the two species share a similar historical recording rate but can find no documentary evidence (i.e., specimens, photos, video, sound recordings) for the persistence of Purple-winged Ground Dove in the wild after the 1980s, despite periodic sighting records, and after which time citizen scientists frequently documented the control species in the wild. Assessments of the probability that the species is extant are sensitive to the method of analysis, and whether records lacking documentary evidence are considered credible. Analysis of the temporal sequence of past records reveals the extent of the historical range contraction of the Purple-winged Ground Dove, while our species distribution model highlights the geographic search priorities for field ornithologists hoping to rediscover the species—aided by the first recording of the species vocalizations which we obtained from interviews with aviculturists. Our interviews also revealed that the species persisted in captivity from the 1970s until the 1990s (up to 150 birds), until a law was passed obstructing captive breeding efforts by private individuals, putting an end to perhaps the best chance we had to save the species from extinction.

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A major barrier to advancing ornithology is the systemic exclusion of professionals from the Global South. A recent special dossier, Advances in Neotropical Ornithology, and a shortfalls analysis therein, unintentionally followed a long-standing pattern of highlighting individuals, knowledge, and views from the Global North, while largely omitting the perspectives of people based within the Neotropics. Here, we review problems with assessing the state of Neotropical ornithology through a northern lens, including discovery narratives, incomplete (and biased) understanding of history and advances, and the promotion of agendas that, while currently popular in the north, may not fit the needs and realities of Neotropical research. We argue that future advances in Neotropical ornithology will critically depend on identifying and addressing the systemic barriers that hold back ornithologists who live and work in the Neotropics: unreliable and limited funding, exclusion from international research leadership, restricted dissemination of knowledge (e.g., through language hegemony and citation bias), and logistical barriers. Moving forward, we must examine and acknowledge the colonial roots of our discipline, and explicitly promote anticolonial research, training, and conservation agendas. We invite our colleagues within and beyond the Neotropics to join us in creating a new model of governance that establishes research priorities with vigorous partici-pation of ornithologists and other stakeholders within the Neotropical region. To include a diversity of perspectives, we must systemically address discrimination and bias rooted in the socioeconomic class system, anti-Blackness, anti-Brownness, anti-Indigeneity, misogyny, homophobia, tokenism, and ableism. Instead of seeking individual excellence and rewarding top-down leadership, institutions in the North and South can promote collective leadership. Authentic collaborations should value the perspectives of those directly involved and affected by policies. In adopting these approaches, we, ornithologists, will join a community of researchers across academia building new paradigms that can reconcile our relationships and transform science.

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The use of autonomous recording units for the monitoring of birds has increased over the years. However, the time needed to listen to the recordings still remains a strong limitation, particularly for highly diverse communities. We aimed to optimize listening effort of trained observers by identifying the periods with the highest species detection rates over 720 1-min files (6 min/h). We detected 90 species within the 720 min. We managed to detect 90% (81) of the species by listening to the top 20% of highly informational minutes (a total of 150 min), a satisfactory result if the goal is to compare communities. Keywords Forest bird communities • Passive acoustic monitoring • Autonomous recording • Sampling methods ZusammenfassungDie optimale Abhörzeit für eine effiziente Einschätzung der Artenvielfalt und -zusammensetzung: eine Fallstudie aus einem neotropischen Wald Der Einsatz autonomer Aufzeichnungsgeräte für das Monitoring von Vögeln hat über die Jahre zugenommen, aber der Zeitaufwand für das Abhören der Aufnahmen stellt dabei nach wie vor eine starke Einschränkung dar, vor allem dann, wenn es um sehr unterschiedliche Vogelgemeinschaften geht. Unser Ziel war es, den Abhöraufwand von geschulten Mitarbeitern zu optimieren, indem wir in 720 Ein-Minuten-Dateien (6 min/h) die Perioden mit den größten Artennachweisen herausfanden. In diesen 720 Minuten identifizierten wir 90 Arten, wobei 90 % (81) aller Arten allein in den top-20% Minutendateinen mit der höchsten Informationsdichte (insgesamt 150 Minuten) nachgewiesen werden konnten. Ein zufriedenstellendes Ergebnis, wenn es um das Vergleichen von Vogelgemeinschaften geht.