How satellites track Antarctic krill: Are these tiny ocean shrimp in danger?

Marine ecosystems rely on food webs that hinge on microscopic life. One creature in particular has drawn the attention of scientists because of its pivotal role in feeding relationships and ocean health.

Researchers have focused on Antarctic krill as a critical link in food chains These small, shrimp-like crustaceans underpin the survival of large marine animals like whales, penguins, and seals.

Observing ocean color

“Antarctic krill are the superheroes of the Southern Ocean. They are tiny, unsung heroes that sustain incredible marine life, but climate change and unsustainable fishing are putting them at risk,” said Rod Downie, chief polar adviser at the wildlife charity WWF-UK.

A new project aims to track these creatures by looking at subtle shifts in how seawater absorbs light. Scientists from the University of Strathclyde, the WWF, and the British Antarctic Survey are working on this approach to gather precise population data.

Light absorption studies

“We start with seawater, then we add in a krill and take a measurement [of how much light the water absorbs], then we add another krill and take another measurement.” said Dr Cait McCarry, who recently returned from Antarctica.

Her team believes those patterns of light absorption can reveal approximate numbers of krill from satellite images.

This method offers a way to observe vast stretches of the Southern Ocean without visiting them, or disturbing marine life in any way.

Climate considerations

Many conservation specialists worry that global warming will impact sea temperatures and threaten the survival of krill populations. Some experts also question whether fishing pressures might weaken this vital link in the Antarctic ecosystem.

Research on rising ocean temperatures shows potential shifts in krill distribution, which may affect predator populations.

Experts highlight the need for protective measures that balance commercial interests with protecting the ocean’s overall health.

Calls for protection

“We urgently need to better manage the fishery and protect krill habitats within a network of marine protected areas. [This project could] give us a new tool to help monitor and safeguard this vital species,” said Downie.

Krill also consume microscopic algae that absorb carbon during photosynthesis. This exchange between animals and plants helps keep greenhouse gases in check, although the shifting climate adds extra stress on both sides of the chain.

Whale connections

Some of the largest marine mammals depend on krill for nutrition. In turn, their waste releases nutrients that support the growth of more microscopic algae, which creates a productive cycle that benefits the entire region.

Scientists see krill as a linchpin in that nutrient exchange. If krill populatioins decrease, whales, seabirds, and even commercial fisheries could feel the repercussions.

Monitoring from afar

Satellites help scientists capture changes across enormous swaths of open water. These images pick up small differences in color that are linked to krill abundance, enabling large-scale observations that were once impossible.

This process avoids intrusive sampling and offers consistent coverage over time. Researchers hope it will streamline the way in which they record shifts in krill hotspots.

Merging new and old methods

Vessel-based surveys have traditionally counted krill, but these can be costly and weather-dependent. Combining ship data with satellite insights may provide a fuller picture for conservation strategies.

Teams are testing how effectively remote readings match direct measurements. Accurate mapping could shape decisions about sustainable fishing quotas in Antarctic waters.

Global relevance

Krill might be small, but they are essential for the health of distant ecosystems that are connected by ocean currents.

Scientists emphasize that changes in krill populations can have ripple effects that influence biodiversity in regions far beyond Antarctic waters.

Some nations rely on krill as a fishery product for animal feed and human supplements. Striking a balance between utilization and preservation is critical for long-term ecological stability.

Looking ahead

Satellite monitoring may become a core part of Antarctic management strategies in the years to come. Many experts anticipate that this technology will strengthen our grasp on the ocean’s hidden patterns and guide policy decisions.

Researchers remain optimistic that a better understanding of krill numbers will be obtained by tracking their populations from space. They hope that this will boost conservation outcomes for every creature in these chilly waters.

This new research was detailed in press releases by the WWF and the University of Strathclyde.

—–

Like what you read? Subscribe to our newsletter for engaging articles, exclusive content, and the latest updates. 

Check us out on EarthSnap, a free app brought to you by Eric Ralls and Earth.com.

—–