Here's why:

* Marine mammalogists specialize in the study of marine mammals, including whales, dolphins, seals, sea lions, and walruses.

* They investigate various aspects of these animals, such as their biology, behavior, ecology, conservation, and interactions with the environment.

While other biologists might contribute to whale research, like oceanographers (studying ocean currents and environments), ecologists (studying whale populations and their ecosystems), or geneticists (studying whale DNA), the marine mammalogist is the primary specialist focused specifically on whales.