During World War II, sonar operators discovered a ‘false seabed’ that appeared to move upwards during the nighttime. In fact, the sound waves were bouncing off huge numbers of small critters. This daily movement is the largest animal migration on the planet, consisting of deep-water animals that hide in the ocean’s twilight then move to the surface after sunset to feed. By far the most abundant fish in this crowd are the lanternfishes. New Zealand researchers are investigating what impact lanternfish migration has on the life cycle of fish we like to eat, and how it may also play a huge role in the Earth’s carbon cycle.

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Guests:

• Professor Jeff Shima, Victoria University of Wellington
• Alisha Gill, Victoria University of Wellington
• Niamh Smith, Victoria University of Wellington

Learn more:

• Read the article for this episode: Lanternfish: small fish, big impact
• Below the twilight zone, in the deepest parts of the worlds’ oceans, including in New Zealand waters, scientists continue to discover new critters.
• The deep ocean makes up the majority of the living space on our planet, where life down there has evolved to cope with the pressure, cold and darkness.
• The Southern Ocean absorbs a huge amount of carbon, but scientists are concerned that may change as the planet warms.

Go to this episode on rnz.co.nz for more details