The strange shrinking of gray whales

One phenomenon that is not fully understood concerns the population of the so-called "guardians of the ecosystem". They have become smaller and smaller over the last two decades. According to a new study, by an incredible 13 percent. This could threaten the survival of the marine mammals.

For the study published in the journal "Global Change Biology", 200 gray whales were observed in the northeastern Pacific.

Their nature is to move close to the coast and feed in shallower and warmer waters. The females were always significantly larger than the males.

Observation by drones revealed that adult whales shrank by around 13 percent between 2000 and 2020. This particularly affects the females, which are now the same size as their male comrades.

Researcher Kevin Bierlich sees this as a possible sign of population decline.

Possible causes could be altered ocean currents that affect plankton growth. As plankton is the main food source for gray whales, this is a plausible approach.

However, this is not scientifically sound evidence. In fact, this poses a puzzle for researchers.