3,661 research outputs found
Extrapair paternity and the evolution of bird song
No full textBird song is usually considered to have evolved in the context of sexual selection. Because extrapair paternity is a major component of sexual selection, mating advantages at the social level for males that produce songs of high quality may be transformed into higher success in extrapair paternity. Therefore, males with longer and more complex songs should suffer less from extrapair paternity intraspecifically, whereas species with high rates of extrapair paternity, reflecting intense sperm competition, should produce more elaborate songs. Although some intraspecific studies demonstrated a negative link between features of songs and extrapair paternity in own nest, others failed to detect such a relationship. Contrary to expectation, a meta-analysis of all studies revealed no significant intraspecific evidence for songs being associated with extrapair paternity. In addition, in comparative analyses based on generalized least squares (GLS) models, we found that no measures of song complexity and temporal output were significantly related to extrapair paternity interspecifically, even when potentially confounding factors such as social mating system, life history, migration, habitat, or sexual dichromatism were held constant. Only plumage dichromatism was significantly related to extrapair paternity. The absence of both intra- and interspecific relationships between measures of song variability and extrapair paternity suggests that factors other than postmating sexual selection have been the important evolutionary forces shaping differences in song. Copyright 2004.bird song; evolution; extrapair paternity; generalized least squares; meta-analysis; repertoire size; sexual selection
G2 & G1 plants species of SW Colorado
No full textPresented at the 16th symposium held on September 27, 2019 in Grand Junction, Colorado.2019 G2 species of SW Colorado -- 2019 G1 species of SW Colorado
A Bird Song Detector for improving bird identification through Deep Learning: a case study from Doñana
No full textPassive Acoustic Monitoring (PAM), which uses devices like automatic audio recorders, has become a fundamental tool in conserving and managing natural ecosystems. However, the large volume of unsupervised audio data that PAM generates poses a major challenge for extracting meaningful information. Deep Learning techniques, particularly automated species identification models based on computer vision, offer a promising solution. BirdNET, a widely used model for bird identification, has shown success in many study systems but is limited at local scale due to biases in its training data, which focus on specific locations and target sounds rather than entire soundscapes. A key challenge in bird species detection is that many recordings either lack target species or contain overlapping vocalizations, complicating automatic identification. To overcome these problems, we developed a three-stage pipeline for automatic bird vocalization identification in Doñana National Park (SW Spain), a wetland facing significant conservation threats. We deployed AudioMoth recorders in three main habitats across nine different locations within Doñana, and the manual annotation of 461 min of audio data, resulting in 3749 annotations covering 34 classes. Our working pipeline included, first, the development of a Bird Song Detector to isolate bird vocalizations, using spectrograms as graphical representations of bird audio data and applying image processing methods. Second, we classified bird species training custom classifiers at the local scale with BirdNET’s embeddings. The best-performing detection model incorporated synthetic background audios through data augmentation and an environmental sound library (ESC-50). Applying the Bird Song Detector before classification improved species identification, as all classification models performed better when analyzing only the segments where birds were detected. Specifically, the combination of the Bird Song Detector and fine-tuned BirdNET increased weighted precision (from 0.18 to 0.37), recall (from 0.21 to 0.30), and F1 score (from 0.17 to 0.28), compared to the baseline without the Bird Song Detector. Our approach demonstrated the effectiveness of integrating a Bird Song Detector with fine-tuned classification models for bird identification at local soundscapes. These findings highlight the need to adapt general-purpose tools for specific ecological challenges, as demonstrated in Doñana. Automatically detecting bird species serves for tracking the health status of this threatened ecosystem, given the sensitivity of birds to environmental changes, and helps in the design of conservation measures for reducing biodiversity loss.This study has received financial support from the BIRDeep project TED2021-129871A-I00, which is funded by MICIU/AEI/10.13039/501100011033/ and the European Union NextGenerationEU/PRTR, as well as grants PID2020-115129RJ-I00 and PTA2021-020336-I from MCIN/AEI/10.13039/501100011033/. AMR has been awarded a fellowship of the CSIC JAE Intro 2023 program (ref. JAEINT23_EX_0243). Logistic and technical support for the installation of the recorders and fieldwork assistance were provided by the ICTS-Doñana (ICTS Doñana, 2025).Peer reviewe
Results of the GAM fitting for total bird richness (BS), native bird richness (BSn), total bird abundance (BA), and native bird abundance (BAn).
No full text<p>Both full model (including all predictors) and the best model according to the shrinkage procedure are shown. s<sub>i</sub> represents the cubic regression spline for the variable and <i>df</i> is the effective degrees of freedom of each term. AIC is the Akaike Information Criteria for the model and <i>D</i><sup>2</sup> is the percentage of explained deviance.</p><p>Abbreviations as follow: DC land cover diversity; BD building density, IS impervious surface, MG municipal green space, NG non-municipal green space, DG domestic garden space, DP distance to the periphery, SW social welfare index, and RV vegetation richness.</p><p>Results of the GAM fitting for total bird richness (BS), native bird richness (BSn), total bird abundance (BA), and native bird abundance (BAn).</p
A Breeding Bird Survey of the Putnam Land, Cheshire County, New Hampshire, USA
No full text<p>Report for a breeding bird survey on ~1,000 acre parcel in SW New Hamphshire, USA in 1993. </p
Coastal raptors and raiders: New bird tracks in the Pleistocene of SW Iberian Peninsula
No full textAvian traces occurring in Pleistocene aeolianite and beach deposits are rare and relatively poorly known, despite being good paleoenvironmental indicators. Passeriform and raptorial birds are especially rare in the track fossil record. Exceptional tracksites were found in the Malhão formation, a Pleistocene coastal aeolianite unit from the SW mainland Portugal, with subunits in the interval ∼187 to ∼27 ka. Two new forms of avian traces were identified, Corvidichnus odemirensis and Buboichnus vicentinus - attributed to the locomotion of Western jackdaw and the locomotion and predation/feeding behaviour of a large Eagle-owl. The last trace fossil may correspond to the first evidence of a raptorial bird-prey interaction found in action in the fossil record. Typical shorebird tracks and trackways attributed to gulls (Laridae) and curlews, and others tentatively compared with Rallidae, such as Eurasian coot, are also discussed within the aeolianite ichnoassemblages. The tracks here described are the first avian ichnotaxa from the Pleistocene of Europe
Coastal raptors and raiders:New bird tracks in the Pleistocene of SW iberian Peninsula
No full textAvian traces occurring in Pleistocene aeolianite and beach deposits are rare and relatively poorly known, despite being good paleoenvironmental indicators. Passeriform and raptorial birds are especially rare in the track fossil record. Exceptional tracksites were found in the Malhão formation, a Pleistocene coastal aeolianite unit from the SW mainland Portugal, with subunits in the interval ∼187 to ∼27 ka. Two new forms of avian traces were identified, Corvidichnus odemirensis and Buboichnus vicentinus - attributed to the locomotion of Western jackdaw and the locomotion and predation/feeding behaviour of a large Eagle-owl. The last trace fossil may correspond to the first evidence of a raptorial bird-prey interaction found in action in the fossil record. Typical shorebird tracks and trackways attributed to gulls (Laridae) and curlews, and others tentatively compared with Rallidae, such as Eurasian coot, are also discussed within the aeolianite ichnoassemblages. The tracks here described are the first avian ichnotaxa from the Pleistocene of Europe.</p
Dependence of unsaturated chloride diffusion on the pore structure in cementitious materials
No full textConceptual analysis is performed to examine the effects of pore features on the water continuity in unsaturated porous systems. The roles of pore features in relative chloride diffusion coefficient (Drc) of mortar specimens at various degrees of water saturation (Sw) were studied based on mercury intrusion porosimetry and resistivity tests. It is found that the role of pore structure in the Drc-Sw relationship is a result of its effect on the water continuity. Porosity and tortuosity are not relevant to the Drc-Sw relationship. A finer pore size distribution or lower pore connectivity tends to result in a lower Drc. The pore size effect on the Drc is pronounced primarily at high Sw, while the Drc is dominated by the pore connectivity at low Sw. Cement mortar with a higher water-to-binder ratio shows larger chloride diffusion at high relative humidity levels but smaller chloride diffusion at low relative humidity levels.Accepted Author ManuscriptMaterials and Environmen
Total Cost of Ownership for Application Replatform by Open-source SW
No full textAbstractIn intra-company IT environment, the use of open-source software (OSS) should be expanded to reduce IT costs and to establish SW governance. This requires the migration of systems from the existing commercial SW to open-source SW, but the attempt of application replatform is prevented by the expenses for application reprogramming and data migration. This study proposes a methodology for TCO calculation of application replatform using open-source SW. In practice, a five-year TCO shows a cost reduction effect of 78% - 83%. This TCO could be further reduced if the application size is increased due to data accumulation and the company gets open-source SW capabilities internally. In addition, it is possible to directly apply an application developed from open-source SW to a virtualized infrastructure environment, which enables to operate in a hybrid cloud environment. This enables a scalable, efficient and flexible IT operation and a sustainable TCO reduction in the futur
Detectability in audio-visual surveys of tropical rainforest birds : the influence of species, weather and habitat characteristics
No full textThis research was funded by the Australian Government’s National Environmental Research Program, the Stuart Leslie Bird Research Award from Birds Australia (http://www.birdsaustralia.com.au/), the Earthwatch Institute (http://www.earthwatch.org/australia/), the Marine and Tropical Sciences Research Facility (MTSRF: http://www.rrrc.org.au/mtsrf). In addition, TAM was partially sponsored by national funds through the Fundação Nacional para a Ciência e Tecnologia, Portugal – FCT under the project (PEst-OE/MAT/UI0006/2011). Date of Acceptance: 27/04/2015Indices of relative abundance do not control for variation in detectability, which can bias density estimates such that ecological processes are difficult to infer. Distance sampling methods can be used to correct for detectability, but in rainforest, where dense vegetation and diverse assemblages complicate sampling, information is lacking about factors affecting their application. Rare species present an additional challenge, as data may be too sparse to fit detection functions. We present analyses of distance sampling data collected for a diverse tropical rainforest bird assemblage across broad elevational and latitudinal gradients in North Queensland, Australia. Using audio and visual detections, we assessed the influence of various factors on Effective Strip Width (ESW), an intuitively useful parameter, since it can be used to calculate an estimate of density from count data. Body size and species exerted the most important influence on ESW, with larger species detectable over greater distances than smaller species. Secondarily, wet weather and high shrub density decreased ESW for most species. ESW for several species also differed between summer and winter, possibly due to seasonal differences in calling behavior. Distance sampling proved logistically intensive in these environments, but large differences in ESW between species confirmed the need to correct for detection probability to obtain accurate density estimates. Our results suggest an evidence-based approach to controlling for factors influencing detectability, and avenues for further work including modeling detectability as a function of species characteristics such as body size and call characteristics. Such models may be useful in developing a calibration for non-distance sampling data and for estimating detectability of rare species.Peer reviewe
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