Climate Change May Seal Our Omega-3 Away

Most health experts agree: Omega-3 fatty acids are essential for human health. However, what they may not know is that these same acids are also vital for maintaining a healthy ocean. Now new research has revealed that climate change may be gradually taking these essential acids away.

That's at least according to a study recently published in the journal Scientific Reports, which reveals how omega-3 fatty acids are not only found in the ocean, but are essential for sustaining a key member of the ocean's most fundamental food web.

Copepods, commonly known as 'ocean fleas,' are lobster-like animals that grow up to only a couple millimeters in length. Yet, despite their small size, these animals also happen to be one of the most abundant living beings on the planet -- outnumbered only by creatures like phytoplankton and prevalent single-celled organisms.

Traditionally, copepods feast on microscopic plants called diatoms, which contribute to the Earth's all-important carbon sink. These plants also happen to be the copepod's primary source of omega-3. When fish in-turn feast on copepods, those fatty acids transfer to them -- the primary reason why seafood and fish oil supplements are chock-full of the stuff. (Scroll to read on...)

And for such high concentrations of omega-3 to be present in their predators, copepods no-doubt store quite a lot of it.

"We don't fully understand why copepods are so dependent on omega-3's but our study shows that these compounds underpin the health of the ocean," lead author of this study, Daniel Mayor from the National Oceanography Centre (NOC), said in a statement.

He added that copepods' dependence could have a lot to do with their impressive migration, one he compares to the seasonal roaming of wildebeests on the plains of Africa.

"They undertake a spectacular annual migration, descending over 1 km into the deep ocean to spend winter in a state of suspended animation after fattening up in spring," Mayor explained. "This is equivalent to you having to walk 875km (~544mi) before being allowed to sleep off your Sunday roast."

What's interesting is that this great migration may also make copepods new 'canaries in a coal mine' for climate change.

According to the study, diatoms 'bloom' in the spring. It is thought that since the start of the diatom bloom is controlled by day length, whereas the timing of copepod growth is controlled by water temperature, global warming could increasingly separate copepods from their source of omega-3's. (Scroll to read on...)

Worryingly, a warming ocean is not just a possibility. It's a reality. It has already been confirmed by the NOAA and international meteorological agencies that 2014 was the hottest year to date, with climbing ocean surface temperatures in the north largely to blame. These temperature hikes have reportedly been getting worse each year, contributing to a 'series of warmer decades' that include notable shifts in seasonal conditions.

That's why Mayor and his colleagues set out to expose food-deprived copepods to predicted climate change scenarios in a bid to better understand our oceans' future. Specifically, they looked at how the omega-3 starved copepods managed to process fats, sugars and proteins.

"Metabolomics is a powerful tool for simultaneously looking at all of the biochemical reactions going on within an organism," added study co-author Ulf Sommer. "We're now able to peer into the inner workings of life and are discovering new and exciting molecules in the process."

The good news is that increasing temperatures and acidity will hardly affect these cornerstone animals for now. However, the authors stress that the threat long-term environmental changes pose to their food supply is still a major concern. It is, they say, just another reason to work on understanding climate change while there's still time.

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