What We Still Do Not Know About Orcas: teacher key

Orcas, grade 12 edition, written for 12th grade and up. Orcas are one of the best-known whales, yet scientists still argue over how many species there are and how to count them. Read where the evidence stands.

Read the book. Print this page for the key.

Questions and answers

1. What did the 2004 workshop of scientists judge?
   • That orcas are one species and should stay so
   • That there were probably several subspecies or species, but the data were not enough to change the name (answer)
   • That Type D is a new species
2. Why do researchers lack an exact count of each ecotype?
   • Orcas have been counted only since the 1970s (answer)
   • Orcas are too small to see
   • Counting was banned
3. How did Scripps scientists record the clicks?
   • With tags on every whale
   • With HARP recorders on the seafloor (answer)
   • With boats near the pods
4. Why can the silence of Bigg's orcas make them harder to study by sound?
   • Their quiet clicks can be buried in background sound (answer)
   • They live too far from land
   • They have no teeth
5. What does "foraging" mean?
   • Calling to a pod
   • Searching for food (answer)
   • Diving deep

Words

• subspecies: sub-kind
• specimen: one sample
• foraging: searching for food
• delisting: removal from list
• Pliocene: ancient epoch