Bird handling techniques and data acquisition in the tropics and subtropics

Der Fang von Vögeln zu wissenschaftlichen Zwecken in den Tropen und Subtropen stellt eine Herausforderung für Ornithologen dar. Probleme aufgrund rechtlicher sowie sozioökonomischer und soziokultureller Rahmenbedingungen lassen sich oft durch eine intensive Vorbereitung und Kooperationen mit lokalen Partnern vermeiden oder reduzieren. Beim eigentlichen Fang sind logistische Herausforderungen wie die Materialbeschaffung vor Ort, aber auch die Ökologie einiger überwiegend tropischer Vogelgruppen zu berücksichtigen. Hier wie auch bei der Probennahme und -lagerung beeinflussen die herrschenden Umweltbedingungen die Arbeit, insbesondere extreme Witterung. Problemlösungenlassen sich jedoch teilweise nur schwer verallgemeinern. Wir unterstreichen die Bedeutung lokaler und regionaler Besonderheiten anhand zahlreicher Beispiele aufgrund eigener Erfahrungen.Capturing birds for scientific purposes in tropical and subtropical areas is particularly challenging. Problems due to general judicial, socio-economic and socio-cultural conditions can often be avoided or reduced by an intensive prearrangement and cooperation with local partners. When actually capturing birds, logistical challenges, differences in predation and the ecology of specific tropical bird groups need to be considered. In this respect and also for sampling and sample storage, environmental conditions, especially extreme weather conditions, are factors to be considered. Troubleshooting and resolving issues related to ornithology in the tropical biomes is not always straightforward. Here we emphasize the importance of local and regional peculiarities by numerous examples based on our own experiences

Effects of cold winters and roost site stability on population development of non-native Asian ring-necked parakeets (Alexandrinus manillensis) in temperate Central Europe – Results of a 16-year census

Asian ring-necked parakeets (Alexandrinus manillensis, formerly Psittacula krameri, hereafter RNP) first bred in Germany in 1969. Since then, RNP numbers increased in all three major German subpopulations (Rhineland, Rhine-Main, Rhine-Neckar) over the period 2003–2018. In the Rhine-Neckar region, the population increased to more than fivefold within only 15 years. Interestingly, there was no significant breeding range expansion of  RNP in the period 2010–2018. In 2018, the total number of RNP in Germany amounted to >16,200 birds. Differences in RNP censuses between years were evident. Surprisingly, cold winters (extreme value, −13.7 °C) and cold weather conditions in the breeding season (coldest month average, −1.36 °C) were not able to explain between-year variation. This finding suggests that in general winter mortality is low – with exceptions for winters 2008/2009 and 2009/2010, and a population-relevant loss of broods is low in our study population. Surprisingly, the social behaviour in terms of spatio-temporal stability of roost sites could well explain positive and negative population trends. Years of spatially stable and regularly used roost sites seem to correlate with increasing population sizes. In contrast, known shifts of RNP among different roost sites or the formations of new roost sites by split are related to population stagnation or a decrease in numbers. Climate change may lead to further range expansion as cities not suitable yet for RNP may become so in the near future.

Records of "Indian" Baya Weaver Ploceus philippinus philippinus (Linnaeus, 1766) and Hooded Wheatear Oenanthe monacha (Temminck, 1825) from Afghanistan (Aves: Passeriformes)

Volume: 62Start Page: 171End Page: 17

Predicting the potential distribution of the invasive Common Waxbill (Passeriformes: Estrildidae)

International audienceHuman transport and commerce have led to an increased spread of non-indigenous species. Alien invasive species can have major impacts on many aspects of ecological systems. Therefore, the ability to predict regions potentially suitable for alien species, which are hence at high risk, has become a core task for successful management. The Common Waxbill is a widespread African species, which has been successfully introduced to many parts of the world. Herein, we used MAXENT software, a machine-learning algorithm, to assess its current potential distribution based on species records compiled from various sources. Models were trained separately with records from the species' native range and from both invaded and native ranges. Subsequently, the models were projected onto different future climate change scenarios. They successfully identified the species known range as well as some regions that seem climatically well suited, where the Common Waxbill is not yet recorded. Assuming future conditions, the models suggest poleward range shifts. However, its potential distribution pattern within its tropical native and invasive ranges appears to be more complex. Although the results of both separate analyses showed general similarities, many differences have become obvious. Niche overlap analysis shows that the invasive range includes only a small fraction of the ecological space that can be found in the native range. Thus, we tentatively prefer the model based on native locations only, but in particular, we highlight the importance of the selection process of species records for modelling invasive species

Avian SDMs : current state, challenges, and opportunities

Quantifying species distributions using species distribution models (SDMs) has emerged as a central method in modern biogeography. These empirical models link species occurrence data with spatial environmental information. Since their emergence in the 1990s, thousands of scientific papers have used SDMs to study organisms across the entire tree of life, with birds commanding considerable attention. Here, we review the current state of avian SDMs and point to challenges and future opportunities for specific applications, ranging from conservation biology, invasive species and predicting seabird distributions, to more general topics such as modeling avian diversity, niche evolution and seasonal distributions at a biogeographic scale. While SDMs have been criticized for being phenomenological in nature, and for their inability to explicitly account for a variety of processes affecting populations, we conclude that they remain a powerful tool to learn about past, current, and future species distributions - at least when their limitations and assumptions are recognized and addressed. We close our review by providing an outlook on prospects and synergies with other disciplines in which avian SDMs can play an important role

Avian SDMs : current state, challenges, and opportunities

Quantifying species distributions using species distribution models (SDMs) has emerged as a central method in modern biogeography. These empirical models link species occurrence data with spatial environmental information. Since their emergence in the 1990s, thousands of scientific papers have used SDMs to study organisms across the entire tree of life, with birds commanding considerable attention. Here, we review the current state of avian SDMs and point to challenges and future opportunities for specific applications, ranging from conservation biology, invasive species and predicting seabird distributions, to more general topics such as modeling avian diversity, niche evolution and seasonal distributions at a biogeographic scale. While SDMs have been criticized for being phenomenological in nature, and for their inability to explicitly account for a variety of processes affecting populations, we conclude that they remain a powerful tool to learn about past, current, and future species distributions - at least when their limitations and assumptions are recognized and addressed. We close our review by providing an outlook on prospects and synergies with other disciplines in which avian SDMs can play an important role

Multivariate environmental similarity scores (MESS) for fossils that fell outside the potential distribution of their species. Negative scores indicate the distance outside the potential niche as a percentage of the niche's size.

<p>For example, a MESS score of −1.6 on BIO6 indicates that the fossil fell 1.6% outside the niche's breadth on the BIO6 climate variable (c.f., <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0072855#pone-0072855-g001" target="_blank">Figure 1</a>). Only incompatible climate variables are reported here (see Appendix S3 in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0072855#pone.0072855.s001" target="_blank">Material S1</a> for a full summary).</p

Relationships between fundamental niches, realized niches, potential niches and geographic distributions as (a) a Venn diagram (after [36], [157]); (b) in climatic niche space (E-space); and (c) in geographic space (G-space).

<p>A species' realized niche (R) is the intersection of its fundamental niche (F), its accessible climate or territory (A), and the climate and territory not barred by biotic interactions (B). Its potential niche (P) is the subset of the fundamental niche for which there is available climate (A), and its potential distribution is the territory with climate tolerable to the species. (F ∩ P) is the range of climate or geography that is climatically tolerable to a species but which is not accessible because of the lack of climate availability (E-space) or geographic barriers (G-space). A fossil may occur in E-space within the species' potential distribution (1), outside the range of available paleoclimate (2), or in paleoclimates which are available but actually not suitable (3). See text for details.</p

Predicted current species richness according to 100% and 90% environmental envelopes (A) as well as historic fluctuations as projected for the last glacial maximum 21 ky BP (B) and the last interglacial (C) according to palaeophylogeographic models of 59 Nearctic chelonians.

<p>Dispersal capacities per species were restricted to the corresponding watersheds (D). For full videos see Appendix S4 in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0072855#pone.0072855.s001" target="_blank">Material S1</a>.</p

Comprehensive overview of phylogeographic and morphometric analyses of North American turtle species.

<p>Given are details on intraspecific variability and differentiation, the marker system, the dating of splits (old = before the LGM, recent = after the LGM) as well as a comparison with the results obtained from paleophylogeographic modeling (1 = pattern mirrored in PPGM; x = pattern not mirrored).</p