The government devised the offshore wind promotion strategy with 3 phases, which include Demonstration Incentive Program, Zone Application for Planning, and Zonal Development. The demonstration incentive program was announced in 2012, and three projects have been selected accordingly. Then, the Directions of Zone Application for Planning (DZAP) was announced in 2015. More than 20 projects have applied for the DZAP, and they are required to pass environmental impact assessments (EIA) to obtain the first step approval for construction. However, the impact of underwater noise on marine mammal during construction and operation phases are very complex. The key issue is that the underwater noise monitoring method has no international standards and it is difficult to measure sufficient and valid data at sea. Moreover, EIA needs very detailed planning and comprehensive preparation to obtain data and analyze the impact assessment from underwater noise. More than 10 countries in Europe already installed offshore wind farms and employ different assessment methods for underwater noise impact. The requirement of the German government’s technical guidelines for underwater noise monitoring and assessment is most rigid and strict. Since 2008, the EU has proposed the “Good Environmental State (GES)” framework for the member states to achieve requirements for the offshore wind energy development monitoring and evaluation. The United States announced the Marine Mammal Acoustic Technical Guidance in 2016, which provides several acoustic thresholds on different species of marine mammal. This study will discuss the latest international technical guidelines for underwater noise monitoring and assessment. Finally, we carried out the report included the applicable method of underwater noise monitoring and assessment based on the development of offshore wind farms in Taiwan.
13-18 Dec 2015
A noisy dinner? Passive acoustic monitoring on the predator-prey interactions between Indo-Pacific humpback dolphins and croakers
Tzu-Hao Lin, Wen-Ching Lien, Chih-Kai Yang, and Lien-Siang Chou
Institute of Ecology and Evolutionary Biology, National Taiwan University
Office of Protected Resources, National Marine Fisheries Service, Silver Spring, MD, USA
The spatio-temporal dynamics of prey resources have been considered as important factors for shaping the distribution and behavior of odontocetes. Indo-Pacific humpback dolphin (Sousa chinensis) is a costal species, which primary feeds on benthic croakers. It has been hypothesized that the distribution pattern and periodic occurrence of humpback dolphins are results of their prey movement. However, the interactions between humpback dolphins and croakers remain unclear. During May 2013 and November 2014, underwater sound recordings were collected in western Taiwan waters. Croaker choruses and humpback dolphin echolocation clicks were automatically detected using custom developed algorithms. Both croaker choruses and dolphin clicks were frequently detected in shallow estuarine waters during spring and summer. In addition, shorter inter-click intervals were detected with higher frequencies in these areas, indicating more likely foraging behavior. Current results suggest that the core habitats of humpback dolphins show an agreement with the areas of prominent croaker chorus. Diurnal cycle analysis showed that croaker choruses were most evident after sunset to until approximately 4 A.M. In estuarine waters, humpback dolphin clicks were most frequently detected during the nighttime, with reduced detection rates after 8 A.M. This suggests that the diurnal behavior of humpback dolphins could be associated with the calling behavior of croakers. Although whether the position of a calling croaker could be passively localized by a dolphin remains unknown, our results indicate that the foraging probability of humpback dolphins may be elevated during the nighttime chorus of croakers. Information regarding the spatio-temporal dynamics of croaker chorus can be important for the conservation management of humpback dolphins. Further details on the predator-prey interactions between humpback dolphins and croakers can be investigated by using hydrophone arrays.
offshore windfarm impact_CH