scholarly journals Social calls influence the foraging behavior in wild big-footed myotis

2021 ◽  
Vol 18 (1) ◽  
Author(s):  
Dongge Guo ◽  
Jianan Ding ◽  
Heng Liu ◽  
Lin Zhou ◽  
Jiang Feng ◽  
...  
Keyword(s):  
Current Knowledge ◽  
Light Trapping ◽  
Low Frequency ◽  
Food Competition ◽  
Insectivorous Bats ◽  
Insect Abundance ◽  
Social Calls ◽  
Abundance And Diversity ◽  
Open Question ◽  
Free Ranging

Abstract Background Why a variety of social animals emit foraging-associated calls during group foraging remains an open question. These vocalizations may be used to recruit conspecifics to food patches (i.e. food advertisement hypothesis) or defend food resources against competitors (food defence hypothesis), presumably depending on food availability. Insectivorous bats rely heavily on vocalizations for navigation, foraging, and social interactions. In this study, we used free-ranging big-footed myotis (Myotis macrodactylus Temminck, 1840) to test whether social calls produced in a foraging context serve to advertise food patches or to ward off food competitors. Using a combination of acoustic recordings, playback experiments with adult females and dietary monitoring (light trapping and DNA metabarcoding techniques), we investigated the relationship between insect availability and social vocalizations in foraging bats. Results The big-footed myotis uttered low-frequency social calls composed of 7 syllable types during foraging interactions. Although the dietary composition of bats varied across different sampling periods, Diptera, Lepidoptera, and Trichoptera were the most common prey consumed. The number of social vocalizations was primarily predicted by insect abundance, insect species composition, and echolocation vocalizations from conspecifics. The number of conspecific echolocation pulses tended to decrease following the emission of most social calls. Feeding bats consistently decreased foraging attempts and food consumption during playbacks of social calls with distinctive structures compared to control trials. The duration of flight decreased 1.29–1.96 fold in the presence of social calls versus controls. Conclusions These results support the food defence hypothesis, suggesting that foraging bats employ social calls to engage in intraspecific food competition. This study provides correlative evidence for the role of insect abundance and diversity in influencing the emission of social calls in insectivorous bats. Our findings add to the current knowledge of the function of social calls in echolocating bats.

scholarly journals The Diverse Calpain Family in Trypanosomatidae: Functional Proteins Devoid of Proteolytic Activity?

Cells ◽  
2021 ◽  
Vol 10 (2) ◽  
pp. 299
Author(s):  
Vítor Ennes-Vidal ◽  
Marta Helena Branquinha ◽  
André Luis Souza dos Santos ◽  
Claudia Masini d’Avila-Levy
Keyword(s):  
Proteolytic Activity ◽  
Current Knowledge ◽  
Current Therapy ◽  
Calcium Dependent ◽  
Administration Routes ◽  
Life Threatening ◽  
Living Organisms ◽  
Almost All ◽  
Open Question ◽  
Calpain Inhibitors

Calpains are calcium-dependent cysteine peptidases that were originally described in mammals and, thereafter, their homologues were identified in almost all known living organisms. The deregulated activity of these peptidases is associated with several pathologies and, consequently, huge efforts have been made to identify selective inhibitors. Trypanosomatids, responsible for life-threatening human diseases, possess a large and diverse family of calpain sequences in their genomes. Considering that the current therapy to treat trypanosomatid diseases is limited to a handful of drugs that suffer from unacceptable toxicity, tough administration routes, like parenteral, and increasing treatment failures, a repurposed approach with calpain inhibitors could be a shortcut to successful chemotherapy. However, there is a general lack of knowledge about calpain functions in these parasites and, currently, the proteolytic activity of these proteins is still an open question. Here, we highlight the current research and perspectives on trypanosomatid calpains, overview calpain description in these organisms, and explore the potential of targeting the calpain system as a therapeutic strategy. This review gathers the current knowledge about this fascinating family of peptidases as well as insights into the puzzle: are we unable to measure calpain activity in trypanosomatids, or are the functions of these proteins devoid of proteolytic activity in these parasites?

Abandonement of coffee agroforests increases insect abundance and diversity

2007 ◽  
Vol 69 (3) ◽  
pp. 175-182 ◽  
Author(s):  
Anne Richter ◽  
Alexandra-Maria Klein ◽  
Teja Tscharntke ◽  
Jason M. Tylianakis
Keyword(s):  
Insect Abundance ◽  
Abundance And Diversity

scholarly journals Aerial low-frequency hearing in captive and free-ranging harbour seals (Phoca vitulina) measured using auditory brainstem responses

2016 ◽  
Vol 202 (12) ◽  
pp. 859-868 ◽  
Author(s):  
Klaus Lucke ◽  
Gordon D. Hastie ◽  
Kerstin Ternes ◽  
Bernie McConnell ◽  
Simon Moss ◽  
...  
Keyword(s):  
Low Frequency ◽  
Auditory Brainstem ◽  
Phoca Vitulina ◽  
Auditory Brainstem Responses ◽  
Harbour Seals ◽  
Free Ranging

scholarly journals How Sensitive are EEG Results to Preprocessing Methods: A Benchmarking Study

2020 ◽  
Author(s):  
Kay A. Robbins ◽  
Jonathan Touryan ◽  
Tim Mullen ◽  
Christian Kothe ◽  
Nima Bigdely-Shamlo
Keyword(s):  
Best Practices ◽  
General Structure ◽  
Spectral Characteristics ◽  
Low Frequency ◽  
Spectral Features ◽  
Eeg Analysis ◽  
Research Reporting ◽  
Automated Processing ◽  
Open Question

AbstractAlthough several guidelines for best practices in EEG preprocessing have been released, even those studies that strictly adhere to those guidelines contain considerable variation in the ways that the recommended methods are applied. An open question for researchers is how sensitive the results of EEG analyses are to variations in preprocessing methods and parameters. To address this issue, we analyze the effect of preprocessing methods on downstream EEG analysis using several simple signal and event-related measures. Signal measures include recording-level channel amplitudes, study-level channel amplitude dispersion, and recording spectral characteristics. Event-related methods include ERPs and ERSPs and their correlations across methods for a diverse set of stimulus events. Our analysis also assesses differences in residual signals both in the time and spectral domains after blink artifacts have been removed. Using fully automated pipelines, we evaluate these measures across 17 EEG studies for two ICA-based preprocessing approaches (LARG, MARA) plus two variations of Artifact Subspace Reconstruction (ASR). Although the general structure of the results is similar across these preprocessing methods, there are significant differences, particularly in the low-frequency spectral features and in the residuals left by blinks. These results argue for detailed reporting of processing details as suggested by most guidelines, but also for using a federation of automated processing pipelines and comparison tools to quantify effects of processing choices as part of the research reporting.

scholarly journals Relative occurrence of the family Kalotermitidae (Isoptera) under different termite sampling methods

Sociobiology ◽  
2018 ◽  
Vol 65 (1) ◽  
pp. 88 ◽  
Author(s):  
Rudolf H Scheffrahn ◽  
James A Chase ◽  
John R. Mangold ◽  
Henry H Hochmair
Keyword(s):  
Sampling Methods ◽  
Light Trapping ◽  
Light Trap ◽  
Habitat Type ◽  
Geographical Location ◽  
Field Studies ◽  
Survey Method ◽  
Termite Species ◽  
Expert Survey ◽  
Abundance And Diversity

The termite family Kalotermitidae constitutes a wood-nesting termite family that accounts for about 15% of all extant termite species. In recent decades, field studies have been carried out to assess termite diversity in various wooded habitats and geographic locations. Three sampling methods have been favored expert, transect, and alate light-trap surveys. Expert collecting is not spatially quantifiable but relies on field personnel to recognize and sample termite niches. The transect method aims to standardize and quantify termite abundance and diversity. Light trapping is a passive method for sampling nocturnal alate flights. We compared our expert survey results and results of published sampling methods for their proportional yields of kalotermitid versus non-kalotermitid encounters. Using an odds ratio statistic, we found that worldwide, there is about a 50.6-fold greater likelihood of encountering a kalotermitid sample versus a non-kalotermitid using the expert survey method and a 15.3-fold greater likelihood using alate trapping than using the transect method. There is about a 3.3 -fold greater likelihood of collecting a kalotermitid specimen versus a non-kalotermitid sample using the expert survey method than using the alate trap method. Transect studies in which only termite species diversity was reported gave similar low Kalotermitidae yields. We propose that multiple biases in sampling methodology include tools, time constraints, habitat type, geographical location, topographical conditions, and human traits account for the divergent outcomes in sampling the abundance and diversity of Kalotermitidae compared to other termite families.

scholarly journals Measuring the Marine Soundscape of the Indian Ocean with Southern Elephant Seals Used as Acoustic Gliders of Opportunity

2017 ◽  
Vol 34 (1) ◽  
pp. 207-223 ◽  
Author(s):  
Dorian Cazau ◽  
Julien Bonnel ◽  
Joffrey Jouma’a ◽  
Yves le Bras ◽  
Christophe Guinet
Keyword(s):  
Indian Ocean ◽  
Low Frequency ◽  
Sound Field ◽  
Elephant Seals ◽  
Ambient Sound ◽  
Southern Elephant Seals ◽  
Operational Systems ◽  
The Indian Ocean ◽  
Passive Acoustic ◽  
Free Ranging

AbstractThe underwater ambient sound field contains quantifiable information about the physical and biological marine environment. The development of operational systems for monitoring in an autonomous way the underwater acoustic signal is necessary for many applications, such as meteorology and biodiversity protection. This paper develops a proof-of-concept study on performing marine soundscape analysis from acoustic passive recordings of free-ranging biologged southern elephant seals (SES). A multivariate multiple linear regression (MMLR) framework is used to predict the measured ambient noise, modeled as a multivariate acoustic response, from SES (depth, speed, and acceleration) and environmental (wind) variables. Results show that the acoustic contributions of SES variables affect mainly low-frequency sound pressure levels (SPLs), while frequency bands above 3 kHz are less corrupted by SES displacement and allow a good measure of the Indian Ocean soundscape. Also, preliminary results toward the development of a mobile embedded weather sensor are presented. In particular, wind speed estimation can be performed from the passive acoustic recordings with an accuracy of 2 m s−1, using a rather simple multiple linear model.

Are vegetation interfaces important to foraging insectivorous bats in endangered coastal saltmarsh on the Central Coast of New South Wales?

2012 ◽  
Vol 18 (4) ◽  
pp. 282 ◽  
Author(s):  
Leroy Gonsalves ◽  
Bradley Law ◽  
Cameron Webb ◽  
Vaughan Monamy
Keyword(s):  
New South ◽  
Individual Species ◽  
Microhabitat Use ◽  
Central Coast ◽  
Insectivorous Bats ◽  
Insect Abundance ◽  
Bat Activity ◽  
Management Actions ◽  
South Wales ◽  
Linear Elements

Conservation of insectivorous bats and their habitats is of increasing concern in Australia and linear elements in the landscape form important foraging habitats for many species. Only recently has use of endangered coastal saltmarsh habitat by bats been documented. Vegetation adjoining saltmarsh provides echolocating bats with linear elements that may be used while foraging and commuting to patches of high insect abundance. We used acoustic detectors to investigate whether individual species and total bat activity along seaward and landward saltmarsh edges was different to the interior of the saltmarsh. Four taxa accounted for greater than 80 % of all bat activity in each zone with similar taxa recorded in both edge and interior zones. However, significantly more bat activity was recorded in edge zones. While differences in microhabitat use by individual species were also found, bat morphology did not account for the observed differences. Conservation managers of saltmarsh and adjoining habitats should consider potential impacts of management actions on foraging bats and their prey. Retention of strips of edge vegetation may help to balance the conservation requirements of endangered coastal saltmarsh habitats and the foraging insectivorous bat populations they sustain.

Ground cover management in a Mediterranean vineyard: Impact on insect abundance and diversity

2019 ◽  
Vol 283 ◽  
pp. 106571 ◽  
Author(s):  
María Gloria Sáenz-Romo ◽  
Ariadna Veas-Bernal ◽  
Héctor Martínez-García ◽  
Raquel Campos-Herrera ◽  
Sergio Ibáñez-Pascual ◽  
...  
Keyword(s):  
Ground Cover ◽  
Insect Abundance ◽  
Abundance And Diversity

scholarly journals Fish aggregating sound technique (FAST): how low-frequency sound could be used in fishing and ranching of cod

2018 ◽  
Vol 75 (4) ◽  
pp. 1258-1268 ◽  
Author(s):  
Björn Björnsson
Keyword(s):  
Fish Species ◽  
Gadus Morhua ◽  
Greenhouse Gas Emission ◽  
Atlantic Cod ◽  
Benthic Communities ◽  
Low Frequency ◽  
Wild Fish ◽  
Sea Cage ◽  
Free Ranging ◽  
Harmful Effects

Abstract In marine fisheries, considerable development has occurred in capture technology. Yet, some of the current fishing methods impact the environment by large greenhouse gas emission, harmful effects to benthic communities, and/or high bycatch of juvenile and unwanted species. It is proposed that for some fish species these deficiencies could be mitigated by classical conditioning using sound and food reward to concentrate wild fish before capture with environmentally friendly fishing gear. Atlantic cod (Gadus morhua), which globally is among the fish species with the highest landed value, can be acoustically trained. In a sea cage, it takes about a week to train a group of naïve cod to associate low frequency (250 Hz) sound with food, whereas the training of a group of naïve cod accompanied with one trained cod takes less than a day. In inshore areas, it takes a few weeks to attract thousands of cod to stations where food is regularly delivered. These conditioned cod wait at the stations for their meals and do not mingle much with the unconditioned cod which hunt for wild prey. It is suggested that by calling acoustically conditioned fish between stations, a much larger number of naïve fish can be gathered. This so-called fish aggregating sound technique (FAST) may thus facilitate the accumulation of wild fish and expedite their capture with a purse seine or a trap in a way that minimizes fuel consumption and mortality of juveniles and unwanted species. The operation of FAST requires exclusive rights of a designated fishing area. The exclusivity makes it possible to on-grow the fish in free-ranging schools and sea cages for several months to increase their size and food quality before capture.

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