Kelp me! It’s a little too warm and it’s getting hard to hear
Effects of Climate Change 1.4
Kelp forests have been through a lot. Let’s take a brief glance at kelp death, why’s it’s happening, and the impacts of it. And then listen into what sound has to do with kelp and why we should care.
Kelp forests play an integral role in the ocean.
- They are a safe haven for many marine species
- By being a protective area for species, kelp promote biodiversity
- There is commercial value in the marine species that reside among the kelp
Yet, there’s a problem. Due to increasing ocean temperatures and frequent presence of heatwaves in the oceans, kelp forests are dying off.
In 2011, the term “marine heatwave” was coined. In the 2011 marine heat wave that occurred in the waters near Australia, there were some days that the surface water temperature reached 5 degrees above the normal monthly average. The heatwave lasted 10 weeks, and the kelp forests were hit particularly hard.
Those kelp forests didn’t grow back. They’re gone, forever.
5 years have passed, and there have been other marine heatwaves, such as “the blob”, which was devastating on marine life and biodiversity, as well as 2014–2015 and the 2016 heatwave that struck marine habitats. We’re witnessing the long-term damage of that heat wave and interpret what that means for the future.
Over 62 miles (100km) of kelp forest died from the Australia’s 2011 marine heatwave. Even when the temperature came down, there are marine species that love eating seaweed, and so, the kelp never had the chance to recover. Commercially, for the marine species the kelp forests protected and sustained and the tourist industry, it’s a loss of over 10 billion dollars.
Now, what’s going on with the inhabitants of kelp forests that haven’t been warmed to death?
Nutrient pollution, that’s what is going on. This is a type of pollution that’s due to agricultural run-off, as well as the run-off from cities and towns.
What is nutrient pollution doing?
Well, it’s causing eutrophication →leading to more algal growth, causing a lack of oxygen, thus, lots of death. This degradation upon marine habitats, such kelp forests and seagrass (which often reside near coastlines), is changing the soundscape of the ocean.
Why is the “soundscape” important?
Glad you asked. Most of the soundscape is a result of the snapping of shrimps, but it also comes from fish vocalizations and the rasping of sea urchins. The sound reduction found in areas of nutrient pollution is comparable to sound loss due to ocean acidification.
Many species rely on the ocean soundscape to find shelter in seagrass and coral reefs. If shrimp aren’t snapping as much, and the other creatures are reducing their noise, what will happen to the marine animals that rely on them? What will happen to the biodiversity in kelp forests and seagrasses?
…Reduction in the soundscape and a loss of kelp forests and sea grasses…let’s open our ears and hear the ocean’s cry for help.
Kelp!
Claudia A.
References:
Andrews, B. K. The importance of kelp forests http://exploretheseafloor.net.au/the-science/kelp-climate-change/ (accessed Oct 2, 2016).
Mills, R. Nutrient pollution is changing sounds in the sea http://phys.org/news/2016-09-nutrient-pollution-sea.html (accessed Oct 2, 2016).
Rossi, T.; Connell, S. D.; Nagelkerken, I. Silent oceans: ocean acidification impoverishes natural soundscapes by altering sound production of the world’s noisiest marine invertebrate. https://www.ncbi.nlm.nih.gov/pubmed/26984624 (accessed Oct 2, 2016).
Slezak, M. ‘The blob’: how marine heatwaves are causing unprecedented climate chaos https://www.theguardian.com/science/2016/aug/15/the-blob-how-marine-heatwaves-are-causing-unprecedented-climate-chaos (accessed Oct 2, 2016).
University of Adelaide. Nutrient pollution is changing sounds in the sea https://www.sciencedaily.com/releases/2016/09/160906103149.htm (accessed Oct 2, 2016).
