Darkness falls. The water glows. Thousands of tiny lights rise from the depths. This is the krill. Nyctiphanes australis is small. Translucent. Pinkish. It lives in swarms. Dense clouds of individuals moving as one. This behaviour confuses predators. It also makes them easy to spot. Whales follow the glow. Fish dive into the cloud. Birds skim the surface. The krill is the fuel. It powers the ocean.
Range covers the seas around New Zealand. It is found in both coastal and offshore waters. It prefers areas with high nutrient levels. Upwellings bring food. Phytoplankton blooms. The krill feeds on these microscopic plants. It filters them from the water. Efficiently. Relentlessly. It converts solar energy into animal protein. A vital step.
Diet is primarily phytoplankton. It also eats zooplankton when available. It grazes continuously. It does not stop. It cannot afford to. Energy demands are high. Swimming in swarms requires coordination. And fuel. The krill provides both for itself and for everything that eats it.
Threats include climate change and ocean acidification. Warming waters affect plankton growth. Acidification weakens shells. Overfishing of predator species can disrupt the balance. But the greatest threat is invisibility. We do not see the krill. We see the whales. We see the
tuna. We forget the foundation. If the krill declines, the structure collapses.
Habitat is the water column. It migrates vertically. Night brings it to the surface. Day sends it deeper. This daily journey avoids visual predators. It is a rhythm as old as the sea. Rise. Feed. Sink. Hide. Repeat.
Life span is one to two years. Short but intense. Reproduction is rapid. Females release thousands of eggs. Most are eaten. Some survive. The cycle continues. The swarm persists. It is fragile. It is resilient. It is everywhere.