Insect Sounds Research Articles

In-Vivo Vibroacoustic Surveillance of Trees in the Context of the IoT.

This work introduces a device for long term systematic monitoring of trees against borers. A widely applied way to detect wood-boring insects is to insert a piezoelectric probe with an uncoated waveguide in the tree trunk and listen for locomotion or feeding sounds through headphones. This approach has several shortcomings: (a) frequent manual inspection of trees is costly and impractical to scale to hundreds or thousands of trees, (b) the larvae could be present but inactive during the inspection time and, (c) when the trees are in urban environments the background noise can be significant and can mask the feeble sounds of wood-boring insects even with the use of specialized headphones. We introduce a remotely controlled device that records and wirelessly transmits on a scheduled basis short recordings of the internal vibrations of a tree to a server. The user can listen remotely or process the recording automatically to infer the infestation state of the tree with wood-boring insects that feed or move inside the tree. When integrated within the IoT framework this device can scale up to automatically monitoring the trees of the entire city. The proposed approach led to detection results in field trials of the pests Xylotrechus chinensis (Chevrolat) (Cerambycidae) and Rhynchophorus ferrugineus Olivier (Coleoptera: Curculionidae).

A new approach to acoustic insect detection in grain storage: Presentation

Insect pests in grain storages can cause severe financial losses. Infested grain needs to be treated and can be sold only with lower profit. Intense infestation can lead to contamination with mycotoxins and total loss of stock. Therefore, an early detection of insect storage pests is of great importance to farmers and storage keepers but is difficult to obtain in large amounts of grain. Besides conventional detection methods such as insect traps and monitoring of temperature and relative humidity, acoustic monitoring can identify insect infestation. Insects in grain and other stored products produce sounds at a low level during movement and feeding activity. A new acoustic system was developed as part of the project “InsectTap” to increase the detectability of insect sounds. Highly sensitive microphones were installed inside a metal tube that increased the surface on which beetle signals could be detected. Additionally, the tube worked as a beetle trap recording all sounds from even one single beetle inside the trap. The tube system was tested in 1 and 8 m³ boxes filled with wheat. Infestation could be detected at a very early stage about 8 weeks before a temperature rise, or beetles at the grain surface indicated an infestation. In the next step, this “Beetle Sound Tube”-System will be installed in different grain silos aiming for automatic early detection and specific identification of infestation. The information provided to the farmer or storage keeper allows early and specific treatment to reduce losses. Additionally, the introduction of parasitoids via the tube system will be tested to increase the efficacy of biological control.

Soundscapes reveal disturbance impacts: biophonic response to wildfire in the Sonoran Desert Sky Islands

While remote sensing imagery is effective for quantifying land cover changes across large areas, its utility for directly assessing the response of animals to disturbance is limited. Soundscapes approaches—the recording and analysis of sounds in a landscape—could address this shortcoming. In 2011, a massive wildfire named “the Horseshoe 2 Burn” occurred in the Chiricahua National Monument, Arizona, USA. We evaluated the impact of this wildfire on acoustic activity of animal communities. In 2013, soundscape recordings were collected over 9 months in 12 burned and 12 non-burned sites in four ecological systems. The seasonal and diel biological acoustic activity were described using the “Bioacoustic Index”, a detailed aural analysis of sound sources, and a new tool called “Sonic Timelapse Builder” (STLB). Seasonal biophony phenology showed a diurnal peak in June and a nocturnal peak in October in all ecological systems. On June mornings, acoustic activity was lower at burned than at non-burned sites in three of four ecological systems, due to a decreased abundance of cicadas directly impacted by the death of trees. Aural analyses revealed that 55% of recordings from non-burned sites contained insect sounds compared to 18% from burned sites. On October nights, orthopteran activity was more prevalent at some burned sites, possibly due to post-fire emergence of herbaceous. Soundscape approaches can help address long-term conservation issues involving the responses of animal communities to wildfire. Acoustic methods can serve as a valuable complement to remote sensing for disturbance-based landscape management.

Oxygen Consumption and Acoustic Activity of Adult Callosobruchus maculatus (F.) (Coleoptera: Chrysomelidae: Bruchinae) during Hermetic Storage.

Acoustic monitoring was applied to consider hermetic exposure durations and oxygen levels required to stop adult Callosobruchus maculatus activity and economic damage on cowpea. A 15-d study was conducted with six treatments of 25, 50, and 100 C. maculatus adults in 500 and 1000 mL jars using acoustic probes inserted through stoppers sealing the jars. Acoustic activity as a result of locomotion, mating, and egg-laying was measured by identifying sound impulses with frequency spectra representative of known insect sounds, and counting trains (bursts) of impulses separated by intervals of <200 ms, that typically are produced only by insects. By the end of the first week of storage in all treatments, oxygen levels declined to levels below 4%, which has been demonstrated to cause mortality in previous studies. Concomitantly, insect sound burst rates dropped below an acoustic detection threshold of 0.02 bursts s−1, indicating that the insects had ceased feeding. Statistically significant relationships were obtained between two different measures of the acoustic activity and the residual oxygen level. Based on the experimental results, a simple equation can be used to estimate the time needed for oxygen to decline to levels that limit insect feeding damage and thus grain losses in hermetic storage containers of different insect population levels and various volumes.

Insect sound production and transmission in plant materials of different compositions and structures

Insects use plants for food and shelter, and many species also have taken advantage of plant acoustical and structural characteristics to communicate for mating and social interaction over extended distances without expending significant energy. Humans have taken advantage of plant acoustical and structural characteristics to detect hidden insect infestations passively by monitoring their feeding and movement activities. This presentation reviews the characteristics of sound transmission as well as the characteristics of insect movement and feeding sounds in plant structures and products. Although insect sounds can be masked by loud background noise, different species produce sounds with particular spectral and temporal patterns that help distinguish them from background signals and from each other. Several practical applications of insect bioacoustics are discussed, including disruption of insect mating, targeting of tree pests, and monitoring of the time course of different pest management treatments.

Effects of Hermetic Storage on Adult Sitophilus oryzae L. (Coleoptera: Curculionidae) Acoustic Activity Patterns and Mortality.

Hermetic storage is of interest to farmers and warehouse managers as a method to control insect pests in small storage facilities. To develop improved understanding of effects of hermetic storage on insect pest activity and mortality over time, oxygen levels, acoustic signals, and observations of visual movement were recorded from replicates of 25, 50, and 100 adult Sitophilus oryzae (L.) (Coleoptera: Curculionidae) hermetically sealed in 500- and 1,000-ml glass jars. Recordings were done for 28 d; twice daily for the first 6 d and twice weekly thereafter. Insect sounds were analyzed as short bursts (trains) of impulses with spectra that matched average spectra (profiles) of previously verified insect sound impulses. Oxygen consumption was highest in treatments of 100 insects/500-ml jar and lowest in 25/1000-ml jars. The rates of bursts per insect, number of impulses per burst, and rates of burst impulses per insect decreased as the residual oxygen levels decreased in each treatment. Activity rates <0.02 bursts s−1, the acoustic detection threshold, typically occurred as oxygen fell below 5%. Mortality was observed at 2% levels. The time to obtain these levels of insect activity and oxygen depletion ranged from 3–14 d depending on initial infestation levels. Acoustic detection made it possible to estimate the duration required for reduction of insect activity to levels resulting in negligible damage to the stored product under hermetic conditions. Such information is of value to farmers and warehouse managers attempting to reduce pest damage in stored crops.

From an old sound recording to a new species in the genus Horatosphaga (Orthoptera: Tettigonioidea: Phaneropterinae: Acrometopini)

Among insects, Orthoptera are a group famous for communicating by sound. This is especially true for bush-crickets (or katydids; Tettigonioidea). All acoustically active species produce sound by rubbing the fore wings (tegmina) against each other, using a stridulatory file situated on the lower side of the left tegmen and a scraper formed by the inner edge of the right tegmen (see e.g., Ragge &amp; Reynolds 1998). Bush-cricket species of the tribe Acrometopini often have complicated stridulatory files and also complex songs, as shown in a recent study (Hemp et al. 2017). During the preparation of that paper we discovered a sound record of a species of the group taken on 16th March 1972 by the entomologist David Hollis in Angola as part of the multi-disciplinary entomological South Western Africa Expedition (for more details see Lane et al. 2011, Pethers 2016). Hollis (principally a hemipterist) published several papers on different groups of insects (see http://bionames.org/authors/David%20Hollis; incomplete), including Orthoptera (see Ingrisch &amp; Willemse 2004). The sound recording was deposited in the British Museum (Natural History) Library of Recorded Insect Sounds, and was later made openly accessible in the BioAcoustica repository (Baker et al. 2015). Hollis had found the animal at light, recorded it on the same day singing on a bush, and brought the specimen (together with two conspecific males) to the Natural History Museum (NHM), London. Here it was later identified as Horatosphaga ?stuhlmanni (Karsch 1896) by D. Ragge, the curator of Orthoptera at the NHM at that time. Under this name (Horatosphaga ?stuhlmanni) the song was described in Hemp et al. 2017. Horatosphaga males are fully winged while females are flightless and plump; sexual dimorphism reaches its extreme form in this group of species. Species of this genus are mostly recorded from open grasslands in savanna habitats up to montane elevations (e.g. H. heteromorpha, Hemp 2013).

Rhythm Generation and Rhythm Perception in Insects: The Evolution of Synchronous Choruses.

Insect sounds dominate the acoustic environment in many natural habitats such as rainforests or meadows on a warm summer day. Among acoustic insects, usually males are the calling sex; they generate signals that transmit information about the species-identity, sex, location, or even sender quality to conspecific receivers. Males of some insect species generate signals at distinct time intervals, and other males adjust their own rhythm relative to that of their conspecific neighbors, which leads to fascinating acoustic group displays. Although signal timing in a chorus can have important consequences for the calling energetics, reproductive success and predation risk of individuals, still little is known about the selective forces that favor the evolution of insect choruses. Here, we review recent advances in our understanding of the neuronal network responsible for acoustic pattern generation of a signaler, and pattern recognition in receivers. We also describe different proximate mechanisms that facilitate the synchronous generation of signals in a chorus and provide examples of suggested hypotheses to explain the evolution of chorus synchrony in insects. Some hypotheses are related to sexual selection and inter-male cooperation or competition, whereas others refer to the selection pressure exerted by natural predators. In this article, we summarize the results of studies that address chorus synchrony in the tropical katydid Mecopoda elongata, where some males persistently signal as followers although this reduces their mating success.

Near-infrared-spectroscopic study on processing of sounds in the brain; a comparison between native and non-native speakers of Japanese

Conclusions The result suggested that mother tongue Japanese and non- mother tongue Japanese differ in their pattern of brain dominance when listening to sounds from the natural world—in particular, insect sounds. These results reveal significant support for previous findings from Tsunoda (in 1970).Objectives This study concentrates on listeners who show clear evidence of a ‘speech’ brain vs a ‘music’ brain and determines which side is most active in the processing of insect sounds, using with near-infrared spectroscopy.Methods The present study uses 2-channel Near Infrared Spectroscopy (NIRS) to provide a more direct measure of left- and right-brain activity while participants listen to each of three types of sounds: Japanese speech, Western violin music, or insect sounds. Data were obtained from 33 participants who showed laterality on opposite sides for Japanese speech and Western music.Results Results showed that a majority (80%) of the MJ participants exhibited dominance for insect sounds on the side that was dominant for language, while a majority (62%) of the non-MJ participants exhibited dominance for insect sounds on the side that was dominant for music.

Peak Finding Algorithm to Improve Syllable Segmentation for Noisy Bioacoustic Sound Signal

Automated identification of animals based their acoustic sound is now preferable by biologist in assisting them to identify animal species for environmental monitoring work. This approach is gradually replacing manual techniques that claimed to be costly and time-consuming. However, it is a challenging task to execute the automated system when the environment is in noisy condition especially in the presence of non-stationary noises such as insect sounds or multiple animal sounds from different species. In this paper, a combination of enhanced start and end point detection namely short time energy (STE) and short time average zero crossing rates (STAZCR) is proposed to improve the syllable segmentation. In this approach, a novel peak finding algorithm is integrated to iteratively narrow down the numbers of local minima and maxima in order to determine the true local maximum value. In this study, the bioacoustics sound samples from frog call database, consists of six hundred and seventy-five frog call data from 15 frog species, recorded in forests located in Kulim and Baling, Malaysia are used. The experimental results demonstrate that 94.13% of performance is achieved by using the proposed method i.e. combination of STE and STAZCR compared to 81.6% of performance for the baseline method, i.e. the combination of the energy and ZCR.

Utilization of Audio Bioha rmony to Improve Rubber (Hevea brasiliensis) Growth in the Nursery

Sound waves research in Indonesia has been carried on the tea crop, peanuts, soybeans and potatoes. The result showed that there was an increase in the effectiveness of nutrient uptake and significant growth rate. This research used manipulated frequency of insect sounds, called “Garengpung”, is known as Audio Bioharmony (ABH). However, application of this technology has not been done in rubber, therefore the aim of the study was to find out effect of ABH toward rubber nursery and to find optimum frequency for rubber nursery. The experiment was arranged in completely randomized design, with a frequency of 0 Hz, 3000 Hz, 3500Hz, 4000 Hz, 4500 Hz and 5000 Hz. The second factor was levels of fertilizer 50%, 75% and 100%. The results showed that the application of sound wave significantly influence growth rate of rubber in the nursery, while the level of fertilizer application had no significant effect. There was no significant interaction between sound wave frequency and fertilizer levels. The best plant height growth rate observed in treatment with 3500 Hz and 75% fertilizer level. The largest stem diameter growth rate was observed in treatment with 4000 Hz and 50% fertilizer level. Based on the regression curves the best frequency to obtain optimal growth of stem diameter was 4271.9 Hz.

Analysis of Acoustic Properties of the Forest in Winter and Spring

This research measures the overall acoustic properties of spring and winter, and their difference is investigated from the perspective of environmental change. Forest in winter is very calm with occasional sound of birds and is devoid of insect sounds. The frequency components of winter forests are shifted towards the lower frequencies however, unique sounds caused by walking on snow compensates for this. Spring forests gives off a sense of gradually increasing vitality moving away from the calm of winter. Especially, as both the variety of bird species that cry and the frequency of those cries are increased significantly in the spring, the ratio of middle to high tone energies of the sound was about three times that of the 10% measured during winter. In all environments volume was louder than winter.

Design of the Sound Insulation Chamber for Stored Grain Insect Sound Detection

A six cubic meter sound insulation chamber is designed based on the principle of double-layer wall sound insulating and porous absorption with the characteristics of stored grain insect action sound. With 3 mm thick plywood as wall material, double - layer spacing 0.08 m, the outer wall being bored, each aperture 1mm, average spacing 1.5 cm, and the hard sound-absorbing material being filled in the two layers, a quasi - double layer perforated structure is built. The ambient noise is uniformly insulated between 125Hz and 2000Hz, and the average sound insulation is about 22dB, and it meets requirements of stored grain insect action sound for the spectrum and SPL. The result shows that the sound insulation chamber has the advantages of small size, economy, and good sound insulation effects.

Q&amp;A: Maestro of the swarm

Swiss acoustic artist Robin Meier manipulates the sounds of insects and birds to create ethereal soundscapes. As his mosquito-inspired musical installation Truce is aired in the French city of Nantes, he talks about firefly synchrony and setting up feedback loops in nature.

Time–Frequency Matrix Feature Extraction and Classification of Environmental Audio Signals

Audio feature extraction and classification are important tools for audio signal analysis in many applications, such as multimedia indexing and retrieval, and auditory scene analysis. However, due to the nonstationarities and discontinuities exist in these signals, their quantification and classification remains a formidable challenge. In this paper, we develop a new approach for audio feature extraction to effectively quantify these nonstationarities in an attempt to achieve high classification accuracy for environmental audio signals. Our approach consists of three stages: first we propose to construct the time-frequency matrix (TFM) of audio signals using matching-pursuit time-frequency distribution (MP-TFD) technique, and then apply the non-negative matrix decomposition (NMF) technique to decompose the TFM into its significant components. Finally, we propose seven novel features from the spectral and temporal structures of the decomposed vectors in a way that they successfully represent joint TF structure of the audio signal, and combine them with the Mel-frequency cepstral coefficients (MFCCs) features. These features are examined using a database of 192 environmental audio signals which includes 20 aircraft, 17 helicopter, 20 drum, 15 flute, 20 piano, 20 animal, 20 bird, and 20 insect sounds, and the speech of 20 males and 20 females. The results of the numerical simulation support the effectiveness of the proposed approach for environmental audio classification with over 10% accuracy-rate improvement compared to the MFCC features.

Perspective and Promise: a Century of Insect Acoustic Detection and Monitoring

Acoustic devices provide nondestructive, remote, automated detection, and monitoring of hidden insect infestations for pest managers, regulators, and researchers. In recent decades, acoustic devices of various kinds have been marketed for field use, and instrumented sample containers in sound-insulated chambers have been developed for commodity inspection. The efficacy of acoustic devices in detecting cryptic insects, estimating population density, and mapping distributions depends on many factors, including the sensor type and frequency range, the substrate structure, the interface between sensor and substrate, the assessment duration, the size and behavior of the insect, and the distance between the insects and the sensors. Considerable success has been achieved in detecting grain and wood insect pests. Microphones are useful sensors for airborne signals, but vibration sensors interface better with signals produced in solid substrates, such as soil, grain, or fibrous plant structures. Ultrasonic sensors are particularly effective for detecting wood-boring pests because background noise is negligible at > 20 kHz frequencies, and ultrasonic signals attenuate much less rapidly in wood than in air; grain, or soil. Problems in distinguishing sounds produced by target species from other sounds have hindered usage of acoustic devices, but new devices and signal processing methods have greatly increased the reliability of detection. One new method considers spectral and temporal pattern features that prominently appear in insect sounds but not in background noise, and vice versa. As reliability and ease of use increase and costs decrease, acoustic devices have considerable future promise as cryptic insect detection and monitoring tools.

An investigation in acoustic insect recognition

This study aims to provide general technicians who manage pests in production with a convenient way to recognize insects. Several viable schemes to identify insect sounds automatically are introduced using sound parameter standardization techniques that dominate speaker recognition technology. The acoustic signal is preprocessed, segmented into a series of sound samples. Melfrequency cepstrum coefficient (MFCC) and Sub-band based cepstral (SBC) are extracted, respectively from the sound samples, and Vector Quantization(VQ) codebook and Hidden Markov Model(HMM) are trained with given features. The matching for a test sample is completed by finding the nearest neighbour in all the VQ codebooks or the best matcher in all HMMs. These methods are evaluated and compared in a database with acoustic samples of 70 different insect sounds. The MFCC and HMM based methods demonstrated their better performance, whose recognition accuracy exceeds 98%.

Diversity of Insect Sounds

Diversity of Insect Sounds

Insect Sounds and Communication: Physiology, Behaviour, Ecology and Evolution

GENERAL ASPECTS OF INSECT SOUNDS Insect Sounds and Communication - An Introduction, M. Claridge Sound and Techniques in Sound Analysis, E. Eliopoulos The Auditory-Vibratory Sensory System in Bushcrickets, W. Roessler, M. Jatho, and K. Kalmring Sense Organs Involved in the Vibratory Communication of Bugs, A. Cokl, M. Virant-Doberlet, and M. Zorovi'c Use of Substrate Vibrations for Orientation: From Behaviour to Physiology, M. Virant-Doberlet, A. Cokl, and M. Zorovi'c Size-Frequency Relationships in Insect Vibrational Signals, R.B. Cocroft and P. De Luca Acoustic Signals and Temperature, A.F. Sanborn Insect Songs - The Evolution of Signal Complexity, W.J. Bailey Song Evolution and Speciation in Bush-Crickets, K.-G. Heller Acoustic Communication in Neuropterid Insects, C.S. Henry Inheritance of Male Sound Characteristics in Drosophila Species, A. Hoikkala Vibrational Communication and Mate Searching Behaviour in Stoneflies, K.W. Stewart and J.B. Sandberg Communication by Substrate-Borne Vibrations in Cave Planthoppers, H. Hoch and A. Wessel Partitioning of Acoustic Transmission Channels in Grasshopper Communities, M. Bukhvalova Insect Species and Their Songs, J. Sueur Is Migration Responsible for the Peculiar Geographical Distribution and Speciation Based on Acoustic Divergence of Two Cicadas in the Aegean Archipelago? S. Drosopoulos, E. Eliopoulos, and P. Tsakalou Acoustic Evolutionary Divergence in Cicadas: The Species of Cicada L. in Southern Europe, J.A. Quartau and P.C. Simoes Acoustic Communication, Mating Behaviour, and Hybridization in Closely Related, Pseudogamic, and Parthenogenetic Species of Planthoppers, S. Drosopoulos Photoperiodism, Morphology and Acoustic Behaviour in the Leafhopper Genus Euscelis H. Strubing and S. Drosopoulos Mutual Eavesdropping through Vibrations in a Host-Parasitoid Interaction: From Plant Biomechanics to Behavioural Ecology, J. Casas and Christelle Magal SOUNDS IN VARIOUS TAXA OF INSECTS Vibratory Signals Produced by Heteroptera - Pentatomorpha and Cimicomorpha Matija Gogala Vibrational Communication in Triatominae (Heteroptera) Claudio R. Lazzari, Gabriel Manrique, and Pablo E. Schilman Vibrational Communication in Treehoppers (Hemiptera: Membracidae) Reginald B. Cocroft and Gabriel D. McNett Acoustic Characters in Classification of Higher Taxa of Auchenorrhyncha (Hemiptera) D. Yu. Tishechkin Acoustic Signals, Diversity, and Behaviour of Cicadas (Cicadidae, Hemiptera) Michel Boulard Vibratory Communication and Mating Behaviour in the European Lantern Fly Dictyophara europea (Dictyopharidae, Hemiptera) Hildegard Strubing Vibrational Communication in Psylloidea (Hemiptera) D. Yu. Tishechkin Mating Behaviour and Vibratory Signals in Whiteflies (Hemiptera: Aleyrodoidea) K. Kanmiya Communication by Vibratory Signals in Diptera K. Kanmiya Stridulation in the Coleoptera - An Overview Andreas Wessel Vibrational Communication in Dung Beetles (Scarabaeidae, Coleoptera) Julia Kasper and Petra Hirschberger Vibratory and Airborne-Sound Signals in Bee Communication (Hymenoptera) Michael Hrncir, Friedrich G. Barth, and Jurgen Tautz References Index

Birdsong tuned to the environment: green hylia song varies with elevation, tree cover, and noise

Animals that communicate acoustically must compete for acoustic space in order to convey their signals effectively. Tropical rainforest birds live in an extremely diverse acoustic community consisting of other birds, mammals, frogs, and many insects. Insects are notable for often producing continuous bands of sound energy at constant frequencies, which vary between species and across habitats. We examined how green hylia (Hylia prasina) song frequencies correlate to insect-generated spectral profiles of ambient noise. We also examined how the environment influenced song frequency by using remote sensing to quantify environmental variables. Using path analysis, we assessed the relative effects of elevation, tree cover, precipitation, and insect sounds on green hylia song frequency. Environmental variables were found to directly influence green hylia song frequencies. Specifically, green hylia sang at lower frequencies at higher elevations and under reduced canopy cover. The environment also influenced green hylia song indirectly through its effect on insect sounds. Green hylia sang at lower frequencies presumably to avoid masking by lower frequency insect sounds. Habitat-dependent divergence in songs within species potentially plays an important role in ecological speciation through its impact on species recognition and mate choice. Our data show that factors related to climate, vegetation, and vocal community can promote such habitat-dependent song variation.