As the climate crisis continues to escalate, one of the most alarming consequences is the increase in toxic algae blooms, which are killing marine life such as dolphins and seals at an alarming rate[1][2]. This year, hundreds of sea lions and dozens of dolphins have been found sick or dead along the Southern California coast, with a toxic algae bloom believed to be the primary cause[2][3][4][5].
The Connection Between Climate Change and Algae Blooms
Climate change has a significant impact on the frequency and intensity of harmful algal blooms (HABs) [1]. Warmer temperatures prevent water from mixing, allowing algae to grow thicker and faster[1]. Algal blooms absorb sunlight, making water even warmer and promoting more blooms[1]. Rising water temperatures, acidification, and low oxygen levels can combine with natural ocean cycles to create extreme marine events, such as marine heat waves, dead zones, and coral bleaching[6]. These events are projected to become more common and severe due to climate change[6].
The Devastating Effects on Marine Life
The rapid growth of harmful algae along parts of the Southern California Coast is believed to have killed hundreds of California sea lions and close to 60 dolphins in the first weeks of June[3]. Many of the dolphins and sea lions affected were pregnant females[3]. The toxin produced by the algae, domoic acid, can cause brain damage, seizures, and death in marine animals[4]. The toxin doesn’t affect humans unless they consume it in contaminated food[4].
The Role of Human Activities
Human activities, such as the use of fertilizers and the release of sewage and runoff from cities and industrial buildings, contribute to the increase in nutrients like nitrogen and phosphorus in water bodies[7][8]. These nutrients promote the rapid growth of algae and cyanobacteria, leading to harmful blooms[7][8]. Warmer temperatures and increased fertilizer and manure runoff during the summer create an ideal environment for toxic algae blooms[9]. However, off-season outbreaks are also becoming more common as the climate crisis causes temperatures and extreme rain events to increase year-round[9].
Preventing and Mitigating the Impact of Algae Blooms
To prevent harmful algal and cyanobacterial blooms from forming, it is essential to use only the recommended amount of fertilizers on farms, yards, and gardens[7]. This will reduce the amount of nutrients running off into nearby water bodies, which can help slow down the growth of algae and cyanobacteria[7]. Additionally, monitoring and reporting any illnesses believed to be caused by algae, cyanobacteria, or their toxins to local or state health departments can help them understand and prevent harmful blooms and illnesses[7].
Conclusion
The increasing occurrence of toxic algae blooms due to climate change poses a significant threat to marine life, including dolphins and seals. As the climate crisis worsens, it is crucial to address the factors contributing to these harmful blooms and implement strategies to mitigate their impact on marine ecosystems. By reducing nutrient pollution and monitoring the health of our water bodies, we can help protect marine life and preserve the delicate balance of our oceans.
Citations:
[1] https://www.epa.gov/nutrientpollution/climate-change-and-harmful-algal-blooms
[2] https://www.nytimes.com/2023/06/21/us/algae-bloom-california-sea-lion-dolphin.html
[3] https://www.fisheries.noaa.gov/feature-story/toxic-algal-bloom-suspected-dolphin-and-sea-lion-deaths-southern-california
[4] https://www.latimes.com/california/story/2023-06-20/whats-killing-hundreds-of-sea-lions-and-dozens-of-dolphins-along-the-southern-california-coast
[5] https://www.newsnationnow.com/science/algae-bloom-poisons-seals-dolphins-southern-california/
[6] https://www.epa.gov/climateimpacts/climate-change-impacts-ocean-and-marine-resources
[7] https://www.cdc.gov/habs/prevention-control.html
[8] https://www.epa.gov/sites/default/files/documents/climatehabs.pdf
[9] https://www.ewg.org/news-insights/news/2023/06/brain-eating-bacteria-arent-threatening-toxic-algae-blooms
