What Researchers Measured: teacher key

Nile Crocodiles, grade 11 edition, written for 11th grade. Researchers have followed, counted and measured Nile crocodiles. They tracked 50 crocodiles at Ndumo Game Reserve, studied body heat and bite force, and estimated how many live in the wild.

Read the book. Print this page for the key.

Questions and answers

1. How many Nile crocodiles did researchers follow at Ndumo Game Reserve?
   • 5
   • 500
   • 50 (answer)
2. What did the Ndumo study find about larger crocodiles?
   • They lived in trees
   • They moved farther and more often (answer)
   • They never moved
3. When do the Ndumo crocodiles return as the floodplain water recedes?
   • In November
   • In January
   • In May (answer)
4. Why might researchers say territory did not make separate home ranges at Ndumo?
   • Crocodiles never moved
   • The reserve was empty
   • Home ranges overlapped a lot in the dry season (answer)
5. When do researchers usually count Nile crocodiles?
   • In the morning (answer)
   • At midnight
   • In the rain

Words

• telemetry: tracking by radio
• territory: defended area
• floodplain: land that floods
• refuge: safe place