Mole Crabs: Biology and Ecology

The video explores the diverse ecosystem beneath the beach surface, focusing on mole crabs, also known as sand crabs. It covers their characteristics, habitat, behavior, and feeding habits. The video also discusses human interactions with mole crabs, including their use as bait and potential risks due to parasites and toxins. Finally, it details the reproduction and lifecycle of mole crabs, highlighting their egg production and larval stage.

What is the primary focus of the ecosystem discussed in the introduction?

• Coral reefs

• Mountain ranges

• Forest ecosystems

• Sand crabs

What is the exoskeleton of mole crabs made of?

• Silica

• Calcium carbonate

• Keratin

• Chitin

Which species of mole crabs is the subject of the investigation?

• Pagurus bernhardus

• Carcinus maenas

• Cancer magister

• Emerita analoga

Where are mole crabs commonly found along the Pacific coast?

• From British Columbia to San Diego

• From California to Oregon

• From Alaska to Baja

• From Washington to Mexico

How do mole crabs burrow into the sand?

• Head first

• Sideways

• Backwards

• Vertically

What do mole crabs use to capture plankton?

• Their mouthparts

• Their legs

• Their feathery antennae

• Their claws

What is a potential risk of consuming mole crabs?

• They can carry parasites or toxins

• They are always poisonous

• They are endangered

• They are too small to eat

During which months does mole crab mating primarily occur?

• Summer and fall

• Spring and summer

• Winter and spring

• Winter and fall

How many eggs can a female mole crab produce?

• Up to 30,000

• Up to 10,000

• Up to 45,000

• Up to 20,000

How long do mole crab larvae drift as plankton?

• 4 to 6 months

• 2 to 4 months

• 1 to 2 months

• 6 to 8 months