Increasing Pollution May Push Cook Inlet Beluga Whale Towards Extinction
There is an enduring struggle in Cook Inlet to maintain a balance between developing oil and natural gas resources while also protecting the watershed’s rich biodiversity and thriving tourism and […]
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There is an enduring struggle in Cook Inlet to maintain a balance between developing oil and natural gas resources while also protecting the watershed’s rich biodiversity and thriving tourism and fishing industries. To date, the scale has tipped in favor of development, and one of the most irrevocable outcomes may be the extinction of the Cook Inlet beluga whale.

The Cook Inlet beluga whale stock is one of five recognized populations within US waters. It has  been genetically and geographically isolated from other beluga whales for thousands of years. The population numbered around 1,300 individuals in the 1980s but precipitously dropped by some 80% in the 80s and 90s due largely to poorly managed subsistence hunting.

In response to their rapid decline, Inletkeeper joined concerned citizens to petition to have the Cook Inlet beluga whale listed as a protected endangered species. In summer 2008, the National Marine Fisheries Service complied. In November 2009, the agency proposed to designate around 2 million acres of critical habitat area to protect the whale. The deal was finalized in 2011 despite objections from the state of Alaska.

Many scientists thought the beluga whales would bounce back quickly after the moratorium on hunting. Yet, this has not been the case. As of January 2020, NOAA Fisheries estimated that the number of beluga whales in Cook Inlet is around 279, a market decrease from their last estimate in 2016 estimating 293 animals.

There are many plausible reasons for the continued decline in Cook Inlet beluga whale numbers. They are particularly vulnerable to a variety of compounding stressors such as habitat destruction, pollution, shipping traffic, noise and competition for prey.

The Cook Inlet population is particularly susceptible to underwater noise in an area replete with high vessel activity, oil and gas exploration and development, and military operations. Loud underwater noises can cause permanent or temporary hearing loss in the whales, inhibiting them from echolocating to find one another and food, and undermining their ability to mate and care for their young.

While underwater noises and compounding stressors have suppressed the Cook Inlet beluga whales over the past decade, an additional threat may push them even closer to extinction: an increase in pollution from oil and gas operations.

“Zero discharge” into navigable waters is the norm for other coastal oil and gas operations which must comply with the 1972 Clean Water Act’s goal of eliminating the discharge of pollutants into the nation’s waters. Yet Cook Inlet is the only coastal location in the US where oil and gas companies can dump contaminated produced water and drilling wastes from their operations back into the Inlet with little or no treatment.  For example, a 2007 Clean Water Act permit allows 100,000 gallons of oil and grease and 887,000 lbs. of toxic metals to be dumped into Cook Inlet each year.

This permit is once again up for renewal, and the 2019 draft permit issued by the Alaska Department of Environmental Conservation (ADEC) is substantially weaker than the 2007 permit. By enlarging the permitted mixing zone areas, DEC is allowing pollutant discharges to increase by 50% for toxic metals such as mercury, silver and zinc. The permit will allow a similar increase of other pollutants such as carcinogenic polycyclic aromatic hydrocarbons (PAHs), which naturally occur in oil and wastewater produced from underground formations.

There is, however, growing evidence to suggest a correlation between an increase in industrial pollution and a decline in beluga whale population viability. A 2018 report studied beluga whales exposed to carcinogenic PAHs that were disposed directly into St. Lawrence Estuary (SLE) by local aluminum smelters from 1926 to 1976. The study reports that the traces of PAHs in the river’s sediments “are likely etiologically related to gastrointestinal epithelial cancers observed in 7% of 156 mature (>19-year old) adult beluga found dead along the shorelines.”

In plain terms, PAHs—the carcinogenic compounds found in produced water from oil and gas production in Cook Inlet—are a “likely cause” of terminal cancer in beluga whales.

Although Congress designed the Clean Water Act to reduce and eventually eliminate the discharge of pollutants, ADEC appears willing to allow Hilcorp and other companies to increase their toxic dumping to maximize profits.

In this instance, economic and conservation goals can reach a manageable solution. The oil and gas industry has the financial and technological capability to reinject their toxic wastes and to eradicate its pollution discharges.

ADEC could issue the revised permit any day, and if it allows toxic dumping to continue, the beluga whales’ increased risk of cancers and other maladies could further reduce the critically endangered population. The consequences, of course, go far beyond beluga whales.  Increased toxic pollution in Cook Inlet will negatively affect Native cultures, our fishing and tourism industries and the overall health of the Cook Inlet watershed.

So speak out for Cook Inlet and the beluga whale. We need your voice to stop ADEC from issuing a short-sighted permit that will unnecessarily pollute Cook Inlet.

You can check out our short video here, and you can take action HERE.

By Ariel Silverman, Inletkeeper Intern


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