Skip to content

Research at St Andrews

Detection and classification of right whale calls using an ‘edge’ detector operating on a smoothed spectrogram

Research output: Contribution to journalArticle

Open Access permissions



A detector has been developed which can reliably detect right whale calls and distinguish them from those of other marine mammals and industrial noise. Detection is a two stage process. In the first, the spectrogram is smoothed by convolving it with a Gaussian kernel and the 'outlines' of sounds are extracted using an edge detection algorithm. This allows a number of parameters to be measured for each sound, including duration, bandwidth and details of the frequency contour such as the positions of maximum and minimum frequency. In the second stage, these parameters are used in a classification function in order to determine which sounds are from right whales. The classifier has been tuned by comparing data from a period when large numbers of right whales were known to be in the vicinity of bottom mounted recorders with data collected on days when it was believed, based on ship and aerial surveys, that no right whales were present. Overall, the detection system is capable of picking out a high proportion of right whale calls logged by a human operator, while at the same time working at a false alarm rate of only one or two calls per day, even in the presence of background noise from humpback whales and seismic exploration. Although it is impossible to reduce the false alarm rate for individual calls to zero whilst still maintaining adequate efficiency, by requiring the detection of several calls within a set waiting time, it is possible to reduce false alarm rate to a negligible level.


Original languageEnglish
Pages (from-to)39-47
JournalCanadian Acoustics
Issue number2
Publication statusPublished - Jun 2004

Discover related content
Find related publications, people, projects and more using interactive charts.

View graph of relations

Related by author

  1. A review of unmanned vehicles for the detection and monitoring of marine fauna

    Verfuss, U. K., Aniceto, A. S., Harris, D. V., Gillespie, D., Fielding, S., Jiménez, G., Johnston, P., Sinclair, R. R., Sivertsen, A., Solbø, S. A., Storvold, R., Biuw, M. & Wyatt, R., Mar 2019, In : Marine Pollution Bulletin. 140, p. 17-29 13 p.

    Research output: Contribution to journalReview article

  2. Cetacean rapid assessment: an approach to fill knowledge gaps and target conservation across large data deficient areas

    Braulik, G. T., Kasuga, M., Wittich, A., Kiszka, J. J., MacAulay, J., Gillespie, D., Gordon, J., Said, S. S. & Hammond, P. S., Feb 2018, In : Aquatic Conservation: Marine and Freshwater Ecosystems. 28, 1, p. 216-230

    Research output: Contribution to journalArticle

Related by journal

  1. Passive acoustic detection and localization of Mesoplodon densirostris (Blainville's beaked whale) vocalizations using distributed bottom-mounted hydrophones in conjunction with a Digital Tag (DTAG) recording

    Ward, J., Morrissey, R., Moretti, D., DiMarzio, N., Jarvis, S., Johnson, M., Tyack, P. & White, C., 1 Mar 2008, In : Canadian Acoustics. 36, 1, p. 60-66 7 p.

    Research output: Contribution to journalArticle

  2. Passive acoustic measurement of dive vocal behavior and group size of Blainville's beaked whale (Mesoplodon densirostris) in the tongue of the ocean (TOTO)

    DiMarzio, N., Moretti, D., Ward, J., Morrissey, R., Jarvis, S., Izzi, A. M., Johnson, M., Tyack, P. & Hansen, A., 1 Mar 2008, In : Canadian Acoustics. 36, 1, p. 166-172 7 p.

    Research output: Contribution to journalArticle

  3. Statistical classification of odontocete clicks

    Gillespie, D. M. & Caillat, M., Mar 2008, In : Canadian Acoustics. 36, 1, p. 20-26

    Research output: Contribution to journalArticle

  4. A remotely-piloted acoustic array for studying sperm whale vocal behaviour

    Schulz, T., Whitehead, H. & Rendell, L. E., Dec 2006, In : Canadian Acoustics. 34, 4, p. 54-55

    Research output: Contribution to journalArticle

ID: 429346