#Whales; #UnderWaterNoise; #WorldWildLifeFund; #OceanNoiseStrategy
Canada/Canadian-Media: Far from being the “silent world” of Jacques Cousteau’s famed documentary, the ocean actually abounds with natural sound. From the acoustic carapace vibrations of American lobster and small grunts from Atlantic cod to the high-frequency echolocation clicks of orca and deep vocalizations of enormous blue whales, the ocean sounds like a veritable symphony.
Whales. Image credit: Worldwide Organization
Travelling five times faster in water than air, sound is the most effective means for marine life to communicate across the ocean’s vast expanse. But their musical notes are slowly sinking below a thickening layer of human-caused noise.
With the increasing industrialization of the ocean over the past several decades — port expansions, shipping intensification, oil and gas exploration and development — human caused noise is starting to overwhelm the natural ocean soundscape. And the impacts are now being documented across marine ecosystems, from whales down to plankton.
Underwater noise pollution has been linked to disrupting normal behaviors, masking communication, impairing feeding, and increasing stress levels; even causing permanent injury or death. Compounding existing stressors like overexploitation, chemical pollution and changing ocean conditions, in contributes to species decline and ecosystem degradation. Such losses are most immediately felt by Indigenous and other coastal communities who depend on marine resources for their wellbeing and livelihood.
How to quiet oceans for marine life
Bordering three oceans, Canada has a global responsibility to be a bold leader in underwater noise pollution prevention and to drive technological innovations that create environmental, economic, and social benefits. Recognizing this need, the federal government has started to develop an Ocean Noise Strategy that will guide and coordinate efforts at managing underwater noise over the next decade.
But to effectively reduce underwater noise pollution, a combination of management efforts with defined targets is required. Here are some of the priorities we’ve identified in our submission to the Canadian government as they build out their strategy.
Set thresholds based on biological limits and informed by Indigenous and local knowledge.
If we try to minimize noise without considering both types of knowledge, we will not necessarily achieve what nature and people need.
Incentivize quieter technologies.
Industry has a critical role to play in spurring the development and adoption of quieter technologies, and we can help nudge them along.
Develop vessel-based and area-based noise targets.
While we must limit noise emissions from ships, different areas also need different approaches, such as quieting heavily trafficked habitats with endangered southern resident killer whales and beluga or preserving natural soundscapes in the rapidly developing Arctic.
Ensure strategies are implemented.
Marine protection legislation very rarely includes shipping restrictions and never includes noise restrictions. Unless Canada’s Ocean Noise Strategy becomes legally binding via regulations or ministerial authority, we’re unlikely to see important biological areas actually free from noise pollution.
WWF-Canada will continue participating in the Ocean Noise Strategy process to ensure Canada creates the quiet spaces that allow the ocean’s natural rhythm to return.
#PacificOcean; #WarmingOceans; #SnakeRiverSalmonSurvival; #Research
The Pacific salmon life cycle is a struggle for survival. It is likely to grow even more so for Snake River salmon populations if the ocean warms, as other previous research indicates that it will in coming decades. Even the largest Chinook populations in the Snake River Basin face a high risk of extinction by the 2060s, according to the research study titled “Climate Change Threatens Chinook Salmon Throughout Their Life Cycle” published this week in Communications Biology.
NOAA Fisheries’ Northwest Fisheries Science Center is using life-cycle modeling to better understand threatened Snake River spring/summer Chinook salmon. The model projects that the species will experience starkly lower survival rates during their years in the ocean in the future compared to now. Recent years may provide a preview. Unusually warm temperatures—including a 2014-2015 marine heatwave—depressed salmon returns to many West Coast rivers, including the Snake and Columbia.
That is particularly troubling since those are the remaining spring Chinook salmon strongholds. They have access to relatively pristine freshwater habitat that provides a reservoir of resilience for the species.
Even large populations may face a high risk of extinction by the 2060s.
Only dramatic increases in the number or survival of juvenile salmon could buffer the likely impacts of climate change, the scientists concluded. While the findings are unsettling, they can help focus conservation efforts to improve the odds for the Columbia Basin’s 13 salmon and steelhead stocks listed under the Endangered Species Act.
“This does not mean it is game over for salmon,” said Lisa Crozier, a research biologist and lead author of the research. “It means that we need to look very closely at the options we have to conserve them, so they make it into the future.”
Habitat Offers Hope
The options include restoring lost and damaged habitat throughout the Columbia River Basin. Modeling has found existing habitat cannot support as many juvenile salmon as it once did. Improving the habitat could increase productivity by supporting more juvenile fish as they feed and grow in streams before migrating to the ocean.
Larger and stronger fish better survive the ocean, so habitat restoration that improves growth can improve their odds. The scientists emphasized the need to understand better the role of competitors, predators, and prey in marine salmon survival and whether management options could help improve salmon prospects. There may also be linkages between estuary restoration and initial growth rates in the ocean that could improve survival.
“The urgency is greater than ever to identify successful solutions at a large scale and implement known methods for improving survival,” the scientists wrote. “Throughout salmon watersheds, improving and expanding access to rearing habitat should increase smolt abundance and body condition, resulting in improved population viability.”
The scientists said, “Management actions that open new quality salmon habitat, improve productivity within the existing habitat, or reduce mortality through direct or indirect effects in the ocean are desperately needed.”
They recognized that actions to benefit salmon could also hold hope for the region’s culture and economy. “We can find new ways to improve salmon habitats while maintaining other benefits for people, like reconnecting floodplains with rivers and natural marshes to recharge aquifers and mitigate flooding, storm surge, and channel erosion,” the report said.
Drawing on Years of DataScientists based the life-cycle models on years of tracking salmon and steelhead through hydroelectric dams on the Columbia and Snake rivers. They also tracked their years in the ocean, adult returns, and fry to smolt survival, among other factors. The models provided information for the development of a biological opinion examining the impacts of the dams on fish protected under the Endangered Species Act.
“This is telling us that it’s going to become increasingly difficult for these species to make it back to the rivers,” said Richard Zabel, director of the center’s Fish Ecology Division and a co-author of the new research. “While salmon have proven themselves to be adaptable over time, we don’t know how they may respond to this relatively rapid change.”
The findings add to earlier research on Pacific salmon’s outlook regarding climate change, including a Climate Vulnerability Assessment published last year. The results assume that the eastern Pacific Ocean will warm in response to rising greenhouse gases, as projected in all 26 global climate models used in the IPCC 5th Assessment. NOAA’s Climate Change portal visualizes these projections. The results could change if ecosystems shift into an unpredictable new state that turns out to be more favorable than expected for salmon.
Researchers have long recognized the great influence of the ocean on salmon population dynamics and the number of salmon that survive to return to rivers as adults to spawn. The new findings underscore that point, with the ocean’s rising heat content pushing up sea surface temperatures closely correlated with increased salmon mortality.
#WhaleWeek; #WorldWhaleDay; #ProtectingOceanGiants
New York/Canadian-Media: Whale Week around the world is being observed from February 16–20, 2021, leading up to World Whale Day on February 21, 2021.
All Images credit: www.fisheries.noaa.gov
World Whale Day is observed every year on the third Sunday in February to inspire the universe with the majesty and beauty of the largest creatures in our oceans as well as reminding us that they need our help to overcome the challenges they face around the globe.
New Online Course for Spotting and Reporting Entangled Whales in Alaska Waters is being offered. NOAA Fisheries has teamed up with The Nature Conservancy (TNC) to develop a new online training course to help them report entanglements.