mentions an abundance of animals belonging to one particular species?

Analysis:

This question requires finding a reader who talks about a large population of a specific type of animal in their chosen location.

Answer:

• Reader A, discussing Hallo Bay, says, 'And there's no shortage of them; Hallo Bay has one of the world's healthiest populations of coastal browns...' This indicates an abundance of a particular species (coastal brown bears).
• Reader C, discussing Costa Rica, mentions it 'boasts the world's highest biodiversity' and 'packs in 850 species of birds and a quarter of the world's species of butterfly.' While this speaks to biodiversity and variety, it doesn't focus on an *abundance of one particular species* in the same way Reader A does.

Answer: A