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Map of the west coast of British Columbia showing the density of vessel traffic (in hours) within 5km by 5km grid cells for the year 2010. The map shows cumulative hours for fishing, government, merchant, passenger & cruise, pleasure & yacht, research, tanker and tug & service vessels. Darker blue colors represent higher traffic density. Vessel traffic data were accessed online from The BC Marine Conservation Analysis, Oil in Canadian Waters Research Group: Ron Pelot (MARIN, Dalhousie University) is the data custodian. Data were accessed from http://bcmca.ca.
Source publication
The purpose of this study is to characterize the soundscape in the Kitimat Fjord system, British Columbia. The channel is expected to undergo development of natural gas export facilities thus increasing ship traffic noise.
Contexts in source publication
Context 1
... 1400 and 1500 are dominated by vessel noise in all of the frequency bandwidths corroborating the strong peaks in the 99.9 percentiles at 1500 ( Figure 13). The high and broad bandwidths are more dominated by vessel noise indicating potentially fewer higher frequency high amplitude event noises in the geophony and biophony of Kitimat Fjord system. ...
Context 2
... identify potential acoustic source mechanisms, the 10 files with the highest levels within each hour were inspected manually for sound sources. Additionally, weather measurements from nearby weather buoys were used to aid in identifying potential source mechanisms associated with weather ( Figure 10). Pearson's correlation coefficients were calculated for median hourly wind speed time series collected at the South Hecate, North Hecate, and Nanakwa shoal weather buoys and median hourly L eq values calculated using the acoustic data from the Gil Island site. ...
Context 3
... are comparable to the data collected at the other hydrophone locations and data collected under potential future increased vessel density conditions. Analysis of the hourly L eq percentiles revealed no obvious diel trend in the data (Figure 13), though it is possible that a small diel trend signal may be obscured by high amplitude noise events generated by ships transiting the channel. Across all frequency bandwidths the 1st, 10th ...
Context 4
... lower three percentiles within the low bandwidth is compressed further within 2 dB re 1µPa. This compression of the lower 50 percentile indicates that half of the time noise falls within 6 dB of the quietest ambient noise (Fig & Table 1). The levels reported for the 90th and 99th percentiles across the bandwidths represent extreme noise events, or the levels exceeded only 10 and 1 percent of the time respectively. ...
Context 5
... order to determine the source mechanisms responsible for some of the extreme event peaks in the L eq percentile plots the 10 loudest files were selected for manual inspection within each hour of the day. These files represent the 10 loudest 30 seconds within each hour of the day over the course of the entire deployment ( Figure 14). It should be noted that the 10 loudest files are not representative of all of the files above the 99th percentile but they do give a good indication of the existing source mechanisms in the ambient acoustic environment of the Kitimat ...
Context 6
... is a strong vessel noise signal in the low and mid frequencies between the hours of 0800 and 1800. Specifically, 1400 and 1500 are dominated by vessel noise in all of the frequency bandwidths corroborating the strong peaks in the 99.9 percentiles at 1500 ( Figure 13). The high and broad bandwidths are more dominated by vessel noise indicating potentially fewer higher frequency high amplitude event noises in the geophony and biophony of Kitimat ...
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Citations
... Critical habitats present opportunities for effective and resource-efficient protection, but any perturbations introduced within their borders, including shipping, can also have outsized effects (Williams et al. 2009). This is the scenario developing within the Gitga'at First Nation (British Columbia, Canada), whose marine territory ( Fig. 1) has experienced 3 simultaneous trends that we shall explore in this study: (1) the repatriation and/or increased use by whales of a historically important whale foraging area, leading to the shortlisting of Gitga'at territory as critical habitat for several Canadian Pacific stocks (fin whales Balaenoptera physalus, Nichol & Ford 2012; humpback whales Megaptera novaeangliae, DFO 2010; northern resident killer whale Orcinus orca, Ford 2006; and Bigg's killer whale, Ford et al. 2013); (2) increases in commercial and recreational traffic associated with the Inside Passage and the nearby port of Kitimat (Heywood 2016); and (3) a series of fuel shipping projects for Kitimat that, when completed, would multiply large ship traffic within Gitga'at waters by more than an order of magnitude (Keen et al. 2022). These fuel projects have placed the otherwise remote Gitga'at community at the center of a national debate about Canada's energy futures (e.g. ...
... Fortunately, the same data gaps that preclude impact assessments of marine traffic in other areas are shrinking in Gitga'at waters. Partially in response to the shipping projects proposed for the region, Gitga'at territory is now one of the best-studied large-whale habitats in the Canadian Pacific, particularly with respect to humpback whales (Ashe et al. 2013, Keen et al. 2017, Wray & Keen 2020, O'Mahony 2021, fin whales , Hendricks et al. 2021, their ecological interactions (Keen 2017a,b, 2018, Keen & Qualls 2018, Qualls 2019, their acoustic habitat (Heywood 2016, Hendricks et al. 2018, 2021, and the area's oceanography (Shan et al. 2020 and references therein). Moreover, whale ship-avoidance behaviors have been studied in similar habitats in southeast Alaska (Gende et al. 2011), and studies elsewhere in the northeast Pacific continue to shed light on aspects of whale behavior relevant to ship-strike risk, such as patterns in dive behavior (Calambokidis et al. 2019. ...
As marine traffic increases globally, ship strikes have emerged as a primary threat to many baleen whale populations. Here we predict ship-strike rates for fin whales Balaenoptera physalus and humpback whales Megaptera novaeangliae in the central territorial waters of the Gitga’at First Nation (British Columbia, Canada), which face increases in existing marine traffic as well as new liquified natural gas (LNG) shipping in the next decade. To do so, we utilized Automatic Identification System (AIS) databases, line-transect surveys, shore-based monitoring, whale-borne tags, aerial drone-based focal follows, and iterative simulations. We predict that by 2030, whale encounters will triple for most vessel types, but the change is most extreme for large ships (length >180 m) in prime whale habitat, in which co-occurrences will increase 30-fold. Ship-strike mortalities are projected to increase in the next decade by 2.3× for fin whales and 3.9× for humpback whales, to 2 and 18 deaths yr ⁻¹ , respectively. These unsustainable losses will likely deplete both species in the coastal region of BC. Models indicate that the largest single source of mortality risk in 2030 will be from the LNG Canada project. Of the mitigation options we evaluated, a 10 knot speed ceiling for all large ships is potentially effective, but the best measure for guaranteed mitigation would be seasonal restrictions on LNG traffic. While certain data gaps remain, particularly with respect to humpback whales, our predictions indicate that shipping trends within Gitga’at waters will impact whale populations at regional levels. We provide our analysis in the R package ‘shipstrike’.
