Impact case study database

(USTAN School of Biology staff are highlighted in bold in the text.)

USTAN research (described in Section 2) has provided key information on the effects of sonar on cetaceans and has estimated the exposure that causes specific behavioural responses. This research has helped NATO navies to effectively manage naval sonar use, update their operating and mitigation procedures, and reduce their environmental impacts. In all the contributing studies, USTAN staff were principal investigators and were actively involved in securing funding, planning, data collection, data analysis and publications. Many collaborators, both internal and external to USTAN, were also involved in the research.

Enabling effective management of naval sonar use:

The research described in Section 2 has provided critical information for effective management of naval sonar use through integration into environmental assessments, regulations and operating procedures in multiple countries, as documented within USA and European impact assessment documents ( S1, S2). Although environmental compliance laws differ by nation, most have regulations that require environmental assessment. For example, the US Navy is required to assess the environmental impact of naval activities between every 5 and 7 years and to request permits to “take” marine mammals, which means including behavioural harassment, injury, and lethal impact. For their most recent “phase III” round of environmental impact statements (EIS) (2017), the US Navy developed exposure-response functions (right side of Figure 1) for estimating the probability of behavioural response to different levels of sonar, using data provided by the BRS project teams ( R1, R2, R4, R5) and using bespoke statistical models based on research conducted under the MOCHA project (e.g., R1) and provided by USTAN researchers. The director of the US Navy Environmental Readiness Divisions states, “ In developing these documents, the Navy thoroughly reviews and incorporates the “best available science” into its acoustic modeling and risk assessment analyses to characterize the environmental impacts of the proposed activities. Research conducted by the University of St Andrews contributed to the best available science utilized during the development of the Navy’s Phase III “At-Sea” EIS/OEIS …… that enable the Navy to obtain permits authorizing continued training and testing on at-sea ranges”. ( S3)

The US Navy, in the development of its EIS ( S1, Section 3, Tables 3-3 to 3-7 therein, pp. 68, 71, 75, 78, 79), referenced USTAN research outputs ( R1, R2, R4, R5) to derive exposure-response functions noting in the acknowledgements for Section 3.1.8: “ Exposure and behavioral response data for the 3S and BRS studies were also directly discussed with the researchers ( P. Miller, P. Wensveen, P. Kvadsheim, F.P. Lam, B. Southall, J. Goldbogen, and J. Calambokidis ) …….. Finally, L. Thomas and P. Wensveen contributed significantly to the Bayesian methodology from which the Navy derived response functions” ( S1, p. 65).

In addition, R1 led the US Navy to adopt exposure-response functions that allow for context-dependent responses at lower exposure levels for its Phase III EIS ( S1). Figure 1 demonstrates the transition from simple exposure-response functions used in the US Navy Phase II EIS prior to the inclusion of USTAN research (left panel of Figure 1) to a more complex, data-driven function used for toothed-whales in the Phase III EIS (right panel of Figure 1). The US Navy also maintained a separate exposure-response function specifically for beaked whales, supported by the growing body of evidence from BRS that these species are highly sensitive to sonar ( R2, R5, S1, S3).

Figure 1: Left: Risk function used in the US Navy 2013 Phase II Environmental Impact Statement (EIS) before inclusion of USTAN research (taken from S1, Figure 3-1, p. 48). BRF refers to ’Behavioural Response Function’. Right: Risk function used in the US Navy 2018 Phase III EIS after inclusion of USTAN research (from S1, Figure 3-4, p. 70). “Dose” on the x-axis indicates Sound Pressure Level (dB re 1 µPa).

Updating of operating and mitigation procedures of European Navies: The Norwegian and The Netherlands Navies have changed specific operating procedures based on USTAN research to reduce the impact of sonar on cetaceans. These navies have used data published by USTAN to develop tools for planning sonar exercises and as real-time decision aids on the bridge of warships. Examples of these assessment tools include the Norwegian SONATE ( S4) and The Netherlands SAKAMATA: “ Research conducted by biologists and analyzed by statisticians at the University of St Andrews has been used for the Royal Netherlands Navy regulations for responsible use of sonar systems, and in particular the risk-assessment tool in use on frigate of the Royal Netherlands Navy, SAKAMATA.” ( S5, p. 2)

BRS results ( R1, R3, R4, R6) have been critical for the Norwegian ‘Instructions for sonar use’ ( S6): “ The integration of St Andrews research into our policy is most clearly evidenced by referring to the document ‘Instruction for use of active sonar in Norwegian waters’ … These guidelines are ‘intended to minimize negative effects of active naval sonars on the marine environment’.” ( S4, referring to S6). For example, the Norwegian Navy’s guidance for planning of intense sonar exercises is based upon sound levels that have been shown by USTAN research to lead to behavioural effects ( R1, R3, R4). In addition, effective planning of the time and place of sonar activities allows for evaluation of the presence of particularly sensitive animals, as identified by BRS studies (e.g., R3, R4). “ This section also contains specific recommendation to avoid intense sonar exercises in areas with high abundance of marine mammals, particularly feeding areas of beaked and sperm whales. This recommendation is informed by research of University of St Andrews which documented significant reductions in feeding for sperm whales and beaked whales due to sonar exposure” ( S4).

The key findings of R6 and related research, which evaluated the efficacy of ramp-up as a mitigation procedure, were used to design the ramp-up procedures used by the Norwegian Navy: “ Research by the University of St Andrews within the 3S project [between 2015 and 2016] was particularly important in the design and testing of ramp-up procedures to give animals time to move away while reducing the impact of ramp-up on the sonar operation itself.” ( S4), and The Netherlands Navy: “ the ramp-up scheme to be used by naval operators has been adapted based on outcomes of the analyses of 3S”) ( S5, p. 2). Use of a shorter ramp-up period is easier for more navies to implement, without decreasing its positive impact on sensitive animals that move away from the sonar source.

In 2014, NATO established the Active Sonar Risk Mitigation Smart Defence Initiative “ to harmonize procedures designed to mitigate the risk of active sonar operations by NATO navies” ( S5). This initiative led to “ recommended common mitigation procedures for the use of sonar within NATO operations, which was accepted as common NATO policy and published in June 2018” ( S5). This common NATO policy was based on contributions from NATO partners, including those with updated operating procedures based on USTAN research ( S5).

*Reduced environmental impact: The environmental benefits of the procedures used in planned NATO training exercises (as updated by USTAN research) are demonstrated by the ability of NATO to conduct large planned international naval operations without strandings, which contrasts against the death of a significant portion of a whale population likely caused by sonar operations that apparently did not follow these procedures. In 2018, NATO conducted a series of planned major naval exercises in beaked whale habitats with no known adverse impact on beaked whales. In contrast, the risks of operating powerful sound sources in the ocean without procedures that incorporate the latest research findings are illustrated by strandings of approximately 100 beaked whales off the Irish and Scottish coasts in 2018. These strandings coincided with a naval operation in the northeast Atlantic. Sonar signals were recorded and “ The Royal Navy were operational in that area at that time: UK Ministry of Defence” ( S7: slide 9). The whales that stranded had died at sea, some with evidence of injuries that have been associated with exposure to naval sonars ( S7: slide 8). Data from the Scottish Marine Animal Stranding Scheme suggests “ Potentially this unusual mortality event involved 1,500-2,000 animals” ( S7: slide 13), mainly made up of Cuvier’s beaked whale ( S7: slide 2). This estimate constitutes approximately 20% of the Cuvier’s beaked whale population in the northeast Atlantic ( S7: slide 13).