The phrase "save the whales" is often used as a general call to protect whales, but it doesn't specify a specific number of whales that need to be saved. The conservation status of different whale species varies, with some considered endangered or critically endangered, while others are considered least concern. In order to effectively protect whale species, it's important to focus on specific populations and threats to those populations.

Some whale species that are considered endangered or critically endangered, and thus in need of urgent conservation action, include:

1. North Atlantic right whale (Eubalaena glacialis): This whale species is critically endangered, with only around 350 individuals remaining. It faces numerous threats, including entanglement in fishing gear, ship collisions, and habitat degradation.

2. Blue whale (Balaenoptera musculus): The blue whale is the largest animal on Earth, and it is listed as endangered. Their populations have been severely depleted due to past whaling and continue to be threatened by hunting, ship collisions, and habitat loss.

3. Fin whale (Balaenoptera physalus): Fin whales are classified as endangered, with an estimated population of around 100,000 individuals. They face similar threats to blue whales, such as hunting, ship collisions, and noise pollution.

4. Humpback whale (Megaptera novaeangliae): Humpback whales were once severely depleted by whaling, but their populations have made a significant recovery in many areas. However, some humpback whale populations are still threatened by hunting, entanglement in fishing gear, and habitat loss.

5. Sei whale (Balaenoptera borealis): Sei whales are classified as endangered, with an estimated population of around 80,000 individuals. They are mainly threatened by hunting, as they are still caught in some commercial and subsistence whaling operations.

It's important to note that the conservation status of whale species can change over time, and new threats may emerge. To effectively protect whales, ongoing research, monitoring, and conservation efforts are necessary, tailored to the specific needs of each species and population.