Automated classification of bees and hornet using acoustic analysis of their flight sounds

International audienceAbstractTo investigate how to accurately identify bee species using their sounds, we conducted acoustic analysis to identify three pollinating bee species (Apis mellifera, Bombus ardens, Tetralonia nipponensis) and a hornet (Vespa simillima xanthoptera) by their flight sounds. Sounds of the insects and their environment (background noises and birdsong) were recorded in the field. The use of fundamental frequency and mel-frequency cepstral coefficients to describe feature values of the sounds, and supported vector machines to classify the sounds, correctly distinguished sound samples from environmental sounds with high recalls and precision (0.96–1.00). At the species level, our approach could classify the insect species with relatively high recalls and precisions (0.7–1.0). The flight sounds of V.s. xanthoptera, in particular, were perfectly identified (precision and recall 1.0). Our results suggest that insect flight sounds are potentially useful for detecting bees and quantifying their activity

A Methodology Based on Bioacoustic Information for Automatic Identification of Reptiles and Anurans

Nowadays, human activity is considered one of the main risk factors for the life of reptiles and amphibians. The presence of these living beings represents a good biological indicator of an excellent environmental quality. Because of their behavior and size, most of these species are complicated to recognize in their living environment with image devices. Nevertheless, the use of bioacoustic information to identify animal species is an efficient way to sample populations and control the conservation of these living beings in large and remote areas where environmental conditions and visibility are limited. In this chapter, a novel methodology for the identification of different reptile and anuran species based on the fusion of Mel and Linear Frequency Cepstral Coefficients, MFCC and LFCC, is presented. The proposed methodology has been validated using public databases, and experimental results yielded an accuracy above 95% showing the efficiency of the proposal

The potential of bioacoustics for surveying carrion insects

Knowledge of the sequential cadaver colonization by carrion insects is fundamental for post-mortem interval (PMI) estimation. Creating local empirical data on succession by trapping insects is time consuming, dependent on accessibility/environmental conditions and can be biased by sampling practices including disturbance to decomposing remains and sampling interval. To overcome these limitations, audio identification of species using their wing beats is being evaluated as a potential tool to survey and build local databases of carrion species. The results could guide the focus of forensic entomologists for further developmental studies on the local dominant species, and ultimately to improve PMI estimations. However, there are challenges associated with this approach that must be addressed. Wing beat frequency is influenced by both abiotic and biotic factors including temperature, humidity, age, size, and sex. The audio recording and post-processing must be customized for different species and their influencing factors. Furthermore, detecting flight sounds amid background noise and a multitude of species in the field can pose an additional challenge. Nonetheless, previous studies have successfully identified several fly species based on wing beat sounds. Combined with advances in machine learning, the analysis of bioacoustics data is likely to offer a powerful diagnostic tool for use in species identification.</p

Automated classification of bees and hornet using acoustic analysis of their flight sounds

To investigate how to accurately identify bee species using their sounds, we conducted acoustic analysis to identify three pollinating bee species (Apis mellifera, Bombus ardens, Tetralonia nipponensis) and a hornet (Vespa simillima xanthoptera) by their flight sounds. Sounds of the insects and their environment (background noises and birdsong) were recorded in the field. The use of fundamental frequency and mel-frequency cepstral coefficients to describe feature values of the sounds, and supported vector machines to classify the sounds, correctly distinguished sound samples from environmental sounds with high recalls and precision (0.96–1.00). At the species level, our approach could classify the insect species with relatively high recalls and precisions (0.7–1.0). The flight sounds of V.s. xanthoptera, in particular, were perfectly identified (precision and recall 1.0). Our results suggest that insect flight sounds are potentially useful for detecting bees and quantifying their activity

(Socio-)ecological tools and insights for a changing climate

In one way or another, climate change is impacting all social, economic, and ecological systems on the planet. Scientists worldwide warn of catastrophic and irreversible damage to social and ecological systems in absence of rapid, far-reaching, and unprecedented shifts in energy and land use. Yet, many social systems continue to operate business-as-usual, and decision-making across multiple levels of social organization continues to neglect the use of scientific evidence to minimize long-term risk. Contemporary biodiversity losses are occurring on scales that surpass the major extinction events in geological records, threatening the loss of critical ecosystem services, such as pollination, that underpin myriad facets of human societies as well as ecosystem resilience. In my dissertation, I call into question conventional lethal sampling approaches for bumble bees, an economically and ecologically important pollinator group, and simultaneously advance non-lethal techniques. Additionally, with aims to advance climate action in Missouri, I investigate how state-level decision-makers and land-use experts are thinking about climate resilience in the context of rural Missouri. More specifically, in chapter one, I explore how the use of lethal sampling, a traditional entomological sampling approach, has changed over time with evidence of numerous declining bumble bee populations. Global declines of bumble bees are welldocumented and have spurred widespread conservation efforts. However, lethal sampling continues to serve as a common entomological practice despite conservation concern. In collaboration with a research team from the Galen lab, I review 411 bumble bee-related publications from 1970-2019 alongside records from over 230,000 pinned bumble bee pinned specimens to discern whether lethal sampling has decreased with heightened conservation awareness and availability of novel non-lethal sampling methods. Our literature review shows that lethal sampling of bumble bees has instead kept pace with publication output. Interestingly, the highest rates of lethal sampling are found in papers demonstrating conservation awareness and persist despite low scholarly impact in comparison to papers based on non-lethal alternatives. Facing numerous pressures, vulnerable bumble bee populations may be less resilient to traditional sampling norms than broadly assumed. We highlight non-lethal sampling alternatives and underscore the need for proactive, empirically informed sampling guidelines that reflect the conservation needs of bumble bee pollinators. In chapter two, I review advances in acoustic monitoring technologies for bumble bees and discuss potential applications. Acoustics show promise for use in bumble bee investigations, as bumble bees create a range of distinguishable sounds while flying, sonicating (buzzing on flowers to eject pollen) and interacting within the colony, making them amenable for acoustical surveys. Acoustics offer an alternative sampling approach that is affordable, scalable, and non-destructive, with potential to augment conservation and agricultural practices. Application of AMT to investigate bumble bees is still nascent in development, and improvements are needed across all stages of the AMT process, from sensor technologies and data transfer to audio classification and user interfaces. I review the sound-producing activities of bumble bees, highlighting extant research and underscoring opportunities for further investigation. I conclude by reiterating the importance of cross-disciplinary collaboration between ecologists and computer scientists to monitor and manage species of conservation concern. In chapter three, I advance acoustic applications in bumble bee research using a combination of field work and literature surveys. Leveraging technological advancements that allow for remote monitoring and automated processing of information, such as acoustics, has been identified as a key next step for pollinator research. I test whether the acoustics of bumble bee flight buzzes can be used to track morphological traits and phenological phases of foragers throughout the season. I used flight cage experiments and a literature survey to extend data on the relationship between the fundamental frequency of flight buzzes and body size across castes and species. I then use these data to test whether acoustics can track caste size dimorphisms across species and variation in intraspecific worker size. Next, I acoustically monitored wild bumble bee colonies in subalpine and alpine ecosystems in Colorado, United States, where I corroborated acoustic data with in-person observations to distinguish phenological phases (queens only vs. queens and workers) of the colonies. I demonstrate that remotely monitoring bumble bee colonies with acoustics can provide large datasets with cues for different morphological and phenological features of the colony and discuss potential applications. In chapter four, I investigate climate resilience in rural Missouri. Rural areas of the United States -- approximately 97 percent of the total land area -- often lag urban areas in the implementation of climate adaptation practices. Understanding how perspectives vary within and among actors in the rural land use decision-making ecosystem can help to identify catalysts and constraints for climate change adaptation planning and action. I conducted semi-structured interviews with 23 experts -- policymakers, state/federal agency professionals, non-profit organization leadership, and researchers -- at the nexus of rural land use, agriculture, natural resources, and conservation in Missouri to elucidate conceptualizations of climate resilience. I aligned interview questions with NOAA's Steps to Resilience to investigate participants' perceptions of the major vulnerabilities of rural communities and landscapes, threats to rural vitality, and potential concrete steps for making rural Missouri more resilient in the face of climate change. I then discuss examples of climate resilience in Missouri and conclude with suggestions for potential next steps towards climate resilience in the state.Includes bibliographical references

Acoustic monitoring and response of katydids (Orthoptera: Tettigoniidae) to the landscape mosaic in a Biosphere Reserve

Thesis (MScConsEcol)--Stellenbosch University, 2017.ENGLISH SUMMARY: A charismatic group within the Orthoptera, katydids can be found in a variety of habitat types world-wide due to their excellent bark and leaf mimicry skills. Most male katydids produce species-specific calls to attract female mates. If katydids, like their close relatives the grasshoppers, can function as effective biological indicators, then acoustic monitoring of katydid songs may result in a novel and non-invasive method to rapidly assess local biodiversity. Furthermore, information regarding threat statuses, distributions and life history traits can be inferred for all South African katydid species, leading to the development of a Katydid Biotic Index (KBI) based on the highly effective Dragonfly Biotic Index. If proven effective, the KBI would allow for biodiversity assessments to account for detailed aspects of katydid species composition in addition to the diversity measures normally utilized for biodiversity assessment (e.g. species richness and abundance). In this thesis, I provide the first steps towards determining whether the KBI could be an effective assessment technique. First I assess the utility of the KBI at a coarse-scale by determining its ability to identify regions of high conservation priority. Secondly, I conduct a fine scale study to determine the response of the katydid assemblage to habitat quality. And lastly, the first two aims are combined to determine whether the KBI is an appropriate method to assess habitat quality at a fine-scale. In Chapter 2, by using a subset of museum records, I investigate the distribution of the katydids within the Cape Floristic Region (CFR), a global biodiversity hotspot. The katydids found within the CFR follow the same trends with regards to threat status, endemism and life history traits to the overall South African katydid assemblage. The KBI assessment method was able to select, at this coarse-scale, the ecosystems of conservation priority. For Chapters 3 and 4, the Kogelberg Biosphere Reserve (KBR) was selected as a study area as it allowed for the acoustic monitoring and direct comparison of katydid assemblages and responses across the core, buffer and transition zones through the use of passive recordings. In Chapter 3 I found that the katydids of the KBR are not complementary across the zones. However, they respond positively in terms of abundance to measured habitat quality when the entire assemblage is considered. In Chapter 4 I found that katydids responded towards coarse-scale habitat quality and they were not as sensitive towards habitat change as was expected. By including abundances of the katydid species in to the KBI calculations, the sensitivity of the KBI as an assessment method was improved. For this reason, katydids in the fynbos biome are likely to not be effective indicators of habitat change on a small scale, likely due to the surprisingly low diversity of katydid species in the KBR. However, if the KBI were to be tested out in forest patches or areas with higher diversity, the KBI may prove more promising. For these reasons, a rapid assessment technique based on the KBI is likely to be more appropriate for some habitat types over others.AFRIKAANSE OPSOMMING: ‘n Charismatiese groep binne die Orthoptera, sabel sprinkane, kan gevind word in 'n verskeidenheid van habitat tipes wêreldwyd as gevolg van hul uitstekende bas en blaar nabootsing vermoë. Die meeste manlike sabel sprinkane produseer spesie-spesifieke geluide om wyfies te lok. Indien sabel sprinkane, soos hul naasbestaandes die sprinkane, effektief as biologiese aanwysers funksioneer, kan akoestiese monitering van sabel sprinkaan geluide lei tot 'n unieke en nie-indringende metode om plaaslike biodiversiteit vinnig te evalueer. Verder, kan inligting rakende bedreiging statusse, verspreiding en lewensgeskiedenis eienskappe afgelei word vir alle Suid-Afrikaanse sabel sprinkaan spesies, wat kan lei tot die ontwikkeling van 'n Sabel Sprinkaan Biotiese Indeks (SBI) gebaseer op die hoogs doeltreffende Naaldekoker Biotiese Indeks (NBI). Indien dit as doeltreffend bewys word, sou die SBI voorsiening maak vir ‘n biodiversiteit assesseringsmetode om rekenskap te gee aan gedetailleerde aspekte van sabel sprinkaan spesiesamestelling bykomend tot die diversiteit maatreëls wat normaalweg gebruik word vir biodiversiteit assessering (bv. spesierykheid en volopheid). In hierdie tesis, wend ek die eerste poging aan om te bepaal of die SBI 'n effektiewe assessering tegniek kan wees. Ek het aanvanklik die gebruiklikheid van die SBI op 'n growwe skaal beoordeel deur die bepaling van die indeks se vermoë om areas van hoë prioriteit vir bewaring te identifiseer. In die tweede plek, doen ek 'n studie op ‘n fyn skaal om die reaksie van sabel sprinkaan spesiesamestelling tot habitat kwaliteit te bepaal. Laastens, is die eerste twee doelwitte gekombineer om te bepaal of die SBI 'n geskikte metode is om habitat kwaliteit te evalueer op 'n fyn skaal. In Hoofstuk 2, met die gebruik van ‘n gedeelte van museum rekords, ondersoek ek die verspreiding van sabel sprinkane binne die Kaapse Floristiese Streek (KFS), 'n globale biodiversiteit brandpunt. Die sabel sprinkane in die KFS volg dieselfde tendense met betrekking tot bedreiging status, endemisme en lewensgeskiedenis eienskappe in vergelyking met die algehele Suid-Afrikaanse sabel sprinkaan versameling. Die SBI assesseringsmetode was in staat, op hierdie growwe skaal, om die ekosisteme van prioriteit vir bewaring te selekteer. Vir Hoofstukke 3 en 4, is die Kogelberg Biosfeerreservaat (KBR) as studiegebied gekies omdat dit akoestiese monitering en direkte vergelyking van sabel sprinkaan spesiesamestelling en reaksies oor die kern, buffer en oorgang sones met gebruik van passiewe opnames toegelaat het. In Hoofstuk 3 het ek gevind dat die sabel sprinkane van die KBR nie aanvullende is oor die sones nie, maar hulle reageer positief in terme van volopheid gemeet teenoor habitat kwaliteit wanneer die hele spesiesamestelling in ag geneem word. In Hoofstuk 4 het ek bevind dat sabel sprinkane gereageer het teenoor growwe skaal habitat kwaliteit en hulle was nie so sensitief teenoor habitat verandering as wat verwag is nie. Deur die insluiting van volopheid van die sabel sprinkaan spesies in die SBI berekeninge is die sensitiwiteit van die SBI as 'n assesseringsmetode verbeter. Vir hierdie rede, is sabel springkane in die fynbos bioom geneig om nie doeltreffende aanduidings van habitat verandering op 'n klein skaal, waarskynlik as gevolg van die merkwaardige lae diversiteit van sabel sprinkaan spesies in die KBR. Maar, indien die SBI getoets sou wees in bos fragmente of gebiede met hoër diversiteit van sabel springkane, kan die SBI as meer belowend bewys word. As gevolg van laasgenoemde redes, is 'n vinnige assessering tegniek gebaseer op die SBI geneig om meer gepas vir sommige tipes habitat teenoor ander te wees