Assemblage of Focal Species Recognizers—AFSR: A technique for decreasing false indications of presence from acoustic automatic identification in a multiple species context

Autoři: Ivan Braga Campos aff001;  Todd J. Landers aff001;  Kate D. Lee aff001;  William George Lee aff001;  Megan R. Friesen aff001;  Anne C. Gaskett aff001;  Louis Ranjard aff005
Působiště autorů: Centre for Biodiversity and Biosecurity, School of Biological Sciences, University of Auckland, Auckland, New Zealand aff001;  Chico Mendes Institute for Biodiversity Conservation, Serra do Cipó National Park, Serra do Cipó/MG, Brasil aff002;  Research and Evaluation Unit, Auckland Council, Auckland, New Zealand aff003;  Landcare Research, Dunedin, New Zealand aff004;  Research School of Biology, ANU College of Medicine, Biology and Environment, The Australian National University, Canberra, ACT, Australia aff005
Vyšlo v časopise: PLoS ONE 14(12)
Kategorie: Research Article
doi: 10.1371/journal.pone.0212727


Passive acoustic monitoring (PAM) coupled with automated species identification is a promising tool for species monitoring and conservation worldwide. However, high false indications of presence are still an important limitation and a crucial factor for acceptance of these techniques in wildlife surveys. Here we present the Assemblage of Focal Species Recognizers—AFSR, a novel approach for decreasing false positives and increasing models’ precision in multispecies contexts. AFSR focusses on decreasing false positives by excluding unreliable sound file segments that are prone to misidentification. We used MatlabHTK, a hidden Markov models interface for bioacoustics analyses, for illustrating AFSR technique by comparing two approaches, 1) a multispecies recognizer where all species are identified simultaneously, and 2) an assemblage of focal species recognizers (AFSR), where several recognizers that each prioritise a single focal species are then summarised into a single output, according to a set of rules designed to exclude unreliable segments. Both approaches (the multispecies recognizer and AFSR) used the same sound files training dataset, but different processing workflow. We applied these recognisers to PAM recordings from a remote island colony with five seabird species and compared their outputs with manual species identifications. False positives and precision improved for all the five species when using AFSR, achieving remarkable 0% false positives and 100% precision for three of five seabird species, and < 6% false positives, and >90% precision for the other two species. AFSR’ output was also used to generate daily calling activity patterns for each species. Instead of attempting to withdraw useful information from every fragment in a sound recording, AFSR prioritises more trustworthy information from sections with better quality data. AFSR can be applied to automated species identification from multispecies PAM recordings worldwide.

Klíčová slova:

Acoustics – Bioacoustics – Birds – Hidden Markov models – Islands – Seabirds – Petrels – Bird song


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Článek vyšel v časopise


2019 Číslo 12