The illustration below shows the food web of the polar bear. What would be the impact on the polar bear if the plankton numbers decreased due to global warming?
The image shows a food web involving a polar bear. Phytoplankton is present just below the surface of the water where the energy of the sun in the diagram penetrates the water and photosynthesis takes place. Arrows point from the phytoplankton down to the ocean floor, where there are organic deposits. The organic deposits have an arrow pointing to crustaceans. The crustaceans have an arrow pointing upward to small fish. Zooplankton is also present and has an arrow pointing toward the small fish. From the small fish an arrow points upward toward a sea lion, and then an arrow points upward from the sea lion to the polar bear.
© 2016 NOAA
The polar bear population would decrease due to fish populations decreasing.
The polar bear population would increase because less ice would mean larger hunting grounds.
The polar bear population would remain unchanged since polar bears do not eat plankton.
The polar bear population would remain unchanged because less ice would mean larger hunting grounds.
