Counting Leopard Seals: teacher key

Leopard Seals, grade 9 edition, written for 9th grade. Leopard seals live alone over huge areas of ice, so counting them is hard. See how scientists used sound, tags and aircraft, and what they found.

Read the book. Print this page for the key.

Questions and answers

1. How did scientists in the Davis Sea count leopard seals?
   • By recording their calls (answer)
   • By weighing them
   • By painting them
2. How many leopard seal calls did the Davis Sea recordings capture?
   • 383
   • 38,270 (answer)
   • 3 million
3. Which survey estimated about 0.31 seals per square kilometre?
   • A visual survey
   • An acoustic survey (answer)
   • A tagging study
4. The acoustic survey found far more seals than the visual survey. What did the 2013 authors conclude?
   • Visual surveys alone are likely to vastly underestimate the population (answer)
   • Seals are easy to see
   • The sound was too quiet
5. What does estimate mean in: one source estimates a population of 35,000?
   • A best guess (answer)
   • A sure count
   • A rule

Words

• acoustic: using sound
• estimate: a best guess
• survey: a careful count
• population: a whole group