Giant Eagle Rays and Pelagic Red Crabs

As spring warms Mexico's west coast, a plankton bloom attracts pelagic red crabs to the surface, turning the waters red. These crabs become prey for migrating seals and whales. Meanwhile, giant eagle rays gather in the Sea of Cortez, performing impressive leaps to attract mates.

What natural event causes the pelagic red crabs to surface along Mexico's west coast?

• A change in ocean currents

• A migration of seals

• A plankton bloom

• A decrease in water temperature

Why do pelagic red crabs become easy prey for seals and whales?

• They are too large to hide

• They are attracted to light

• They are nocturnal creatures

• They are controlled by the current

What is the effect of the crabs forming dense swarms?

• They block out sunlight

• They create a barrier for boats

• They attract more predators

• They change the water's color

What draws giant eagle rays to the Sea of Cortez?

• The plankton bloom

• The migration of whales

• The presence of seals

• The warm water temperature

How do giant eagle rays try to attract mates?

• By changing color

• By forming small groups

• By leaping out of the water

• By making loud calls

What is the maximum height giant eagle rays can leap out of the water?

• Six feet

• Four feet

• Five feet

• Three feet

What is the primary reason for the eagle rays' acrobatic leaps?

• To escape predators

• To cool off in the air

• To find food

• To get noticed by potential mates