MINUTES BIAS Data Collection Finished: Then What? 17‐18th of March, 2015 Marine Biological Research Center University of Southern Denmark Hindsholmsvej 11 5300 Kerteminde Denmark Organized by Magnus Wahlberg, University of Southern Denmark (telephone: +45‐22163950, email: [email protected]) and Jakob Tougaard, Aarhus University Minutes by Magnus Wahlberg Program (all lectures in ‘Summer lab’, break‐up discussions may take place in other locations) Tuesday 17th of March 14.00 Magnus Wahlberg and Jakob Tougaard: Short round‐table presentation of workshop goals and participants 14.30 Jakob Tougaard: CPOD performance under various noise conditions 15.00 Johanna Stedt: Spatial/temporal patterns of harbour porpoises studied with C‐PODs around Kullaberg, Sweden 15.30 Magnus Wahlberg / Anton Larsson: The effect of ship noise on porpoise activity around Kullaberg, Sweden 15.45 Eeva Sairanen: The effect of shipping on harbour porpoise activity 16.00 Johan Fridström: BIAS data analysis on shipping noise levels 16.15 Leif Persson: Something about ambient noise 16.40 Alexander Klauson: Quick comment on background noise 16.45 Julia Carlström: From SAMBAH to LAMBADAH and MAMBO 17.15 Mirko Mustonen: BiAS noise data combined with AIS 17.30‐18.00 General discussion 19.30 Dinner Wednesday 18th of March 9.00‐11.00 Break‐up groups discussing sharing / partitioning of data and analysis techniques 11.00‐12.00 Sum‐up and farewell. Participants: Aleksander Klauson (Professor, Tallinn University of Technology, Estonia, [email protected]) Eeva Sairanen (PhD student, Helsinki University, Finland, [email protected]) Jakob Tougaard (Senior scientist, Aarhus University, Denmark, [email protected]) Joanna Sarnocinska (MSc student, University of Southern Denmark, [email protected]) Johan Fridström (MSc student, Stockholm University, Sweden, [email protected]) Johanna Stedt (Biologist, Länsstyrelsen, Sweden, [email protected]) Julia Carlström (scientist, Aquabiota, Sweden, [email protected]) Leif Kg Persson (senior scientist, FOI, Sweden, [email protected]) Line Hermannsen (Reserach assistant, Aarhus University, Denmark, [email protected]) Lonnie Mikkelsen (Reserach assistant, Aarhus University, Denmark, [email protected]) Magnus Wahlberg (Associate Professor, University of Southern Denmark, [email protected]) Mirko Mustonen (MSc student, Talinn University of Technology, Estonia, [email protected]) Minutes from the meeting Jakob Tougaard: CPOD and ambient noise Lab tests where C‐PODS are injected with simulated porpoise clicks and pink noise/ultrasonic clicks indicate that the detection of porpoise clicks is compromised by ambient noise levels. Both ‘click noise’ and ‘ship noise’ has a large effect on the detection of porpoise clicks. This makes it difficult to use C‐PODS to study the impact on porpoises of noise. Another funny (or maybe not) result is that at very low noise levels there are no detections at all. Johanna Stedt Porpoise activity was studied with 6 CPODs deployed throughout the spring and summer of 2014 around Kullaberg, Sweden. Data reveals strong diurnal, lunar and spatial patterns in the porpoise distribution. The diurnal pattern is not the same during different seasons, but varies so that the porpoise activity sometimes peak during the day, sometime during the afternoon, and most often during the night. Magnus Wahlberg & Anton Larsson Two stations with CPODs and SM2M/DSG data loggers were deployed off Kullaberg during the summer of 2013. The noise levels of shipping and the porpoise activity from CPODS was compared, without any strong conclusions being drawn on any effects on porpoise activity from the varying noise levels. Analysis was likely compromised by too long averaging window for the boat noise. Eeva Sairanen MSc thesis (finished): Weather and ship induced sounds and the effect of shipping on porpoise activity. The LAMBADAH porpoise and BIAS shipping noise data was correlated. It was possible to compare the noise level with the distance to the ship using AIS data. The clearest effect of shipping is within 5 km from the boats. If porpoise activity is a function of ship noise then this data can be used to assess at which distances it is relevant to consider noise effects on porpoises. Eeva applying for a PhD: currently the scope is broad, looking at what kind of noise are Baltic Sea marine mammals and fish exposed to? Eeva’s data could probably also be used to measure transmission loss from ship noise, which would be a very interesting result to obtain. Probably this is also modelled from Thomas Folgot. Johan Fridström MSc Thesis thesis (ongoing): Statistical description of ambient noise in the Baltic Sea and its influence on the range of passive sonar. How is noise depending on shipping, waves and wind? A large part of the work deals with quality control of data: 1. Check for stationarity: is the signal similar to previous signal: same mean as previous: autocorrelation. 2. Perform Grubb’s test to remove outliers. Then weather and wind data is compared to noise data. The advantages of using the same analysis in different projects were emphasized. Leif Persson : Something about ambinent noise Background acoustic noise is traditionally defined as being without distinguishable sources. However, this definition was changed by EU TSG group to: all sound except that resulting from deployment, operation and recovery. The components of ambient noise are: sea surface noise, biological noise, natural seisimic / geoacostic noise (there is actually a 1 Hz noise that has the same amplitude all around the world and could be used for calibration, if it were not being filtered out in most current data loggers), and boat traffic noise. We should aim for deriving a ‘Wenz curve of the Baltic sea’ from the BIAS data. Aleksander Klauson Baltic noise curves from Estonia, to exemplify some of Leif’s points. Julia Carlström: LAMBADAH and MAMBO EU Habitat’s directive demands strict protection of porpoises. For us, of special importance are: Articles 9 and 10, Descriptors 1&11: quality and occurrence of habitats / introduction of energy (noise, n.b. impact of introduction of noise). LAMBADAH is a project collecting CPOD data during BIAS independent of SAMBAH. The aims are to investigate the fine‐scale impact of shipping noise on harbour porpoise echolocation, the large‐scale impact of shipping noise on harbour porpoise distribution, and to find indicators of shipping noise impact on harbour porpoise habitat and distribution. The project is currently unfunded. It is of special interest to use soundscape models and impact indicators: spatial predictions of potential impact/realised impact ‐> indicators can be monitored over a longer time. On top of this, the MAMBO (Management Actions and Conservation Measures for the Baltic Sea Odontocete) project is currently applied for from EU‐LIFE. It will use parts of LAMBADAH, fine‐scale surveying of harbour porpoises, underwater noise and ships around the Mid‐Sea Bank, data collection and analyses for detailed investigation of harbour porpoise clicks of calves vs. adults, Baltic Proper population vs. Belt Sea population, bycatch, underwater noise, protected areas, management needs. There will be a planning meeting in May in Stockholm, and project proposal submission is June 30. Mirko MSC study of ship noise modelling using AIS and BIAS noise level at 63Hz. Analysis collected in so‐called Bitbucket repository for analysis and comments. General discussion As a final point on the first day, we discussed relevant issues to treat during the second day. We decided to break up into two working groups discussing CPOD and noise measurement issues, respectively. Also, each participant gave a brief statement of what was the most interesting point they got inspired to continue discussing from today’s meeting: the possibility to extrapolate findings from porpoise reactions to ship noise to other areas; the possibility to analyse what different contributions to Wenz curves could mean (we should divide in different teams studying different spectral ‘bumps’); common discussions on analysis techniques, and also trying to develop a signal analysis and reporting standard; formulating best practise / good practise; learn how to measure impact of noise; combining AIS and environmental data in modelling; studying ship noise and its impact as well as ship noise characteristics; and correlating shipping with CPOD data. Wednesday 18th of March CPOD working group (Jakob, Magnus, Lonnie, Julia, Joanna, Johanna) ‘Extent of the problem’: Are the noise levels comparable to realistic noise levels? We could study this by: o Masking studies of CPODs with acoustics signals o Field study CPOD vs. PAMGUARD o Compare porpoise enclosure recordings vs. CPOD recordings o Comparing performance of different loggers: TPOD, CPOD, and Soundtrap o Contact Jens Koblitz about COSAMM project on TPOD/CPOD performance o Detections of clicks under great signal‐to‐noise ratio Can C‐PODs be used to study efficiency the effect of ships? o Situations which are good: If BW smaller than 25 kHz Including transmission loss in the calculations At what distance can the problem be studied? If duty cycle of noise is low, we can study detection before and after the pulse Think about it as a threshold problem: compare CPOD detections at special sound levels High frequency components with sound trap & CPOD BIAS: Total number of CPOD clicks vs. SM2M data Echo sounders: do they use it on larger boats? There is an algorithm in the CPOD called ‘GENMEC which works well to identify echo sounders in CPOD data. CPOD calibration: methodology should be developed SAMBAH data: accessible through SMHI eventually MAMBO Funding: NOVANA project cofounding? Pinger disturbances Noise group o Formed the group: it will communicate by Skype and try to arrange meetings o There is different data resolution in different countries (should be standardized?): E.g., Estonia has data two times per hour, wind every 10 min. o Estonia: we have a standard for BIAS noise data presentation, will be good to make a standard for AIS data files to help data sharing. o Estonia: ship analysis, CPA spectra for each ship, several ships at the same peak. Spectrogram Sonic visualizer, bottom, sound speed, finish the system o Finland: MSc thesis for more stations, separate wind, ship noise o Denmark: ship specification, ship noise, speed o Sweden Hydrographic data for longer time Jan‐June, AIS data, Summer‐Winter distinction o Ship noise, sea state 0, ship classification, 5km range o Number of ships per station monthly – distance, speed o Averaging – how to do this? o Timing of low sea state, shipping index low, et cetera o o o o o o Reference ship passing all bias stations Low sea states: ship contribution to the Wenz curves Road map AIS data: number of ships per data, A and B categories Standardization issues: tersband levels, or Hz levels,63 or 126 kHz? Nordic Council application? Workshop attendants with a porpoise at Fjord&Bælt. We plan to organize a follow‐up meeting this fall in Stockholm.
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