The dolphin's in danger. -- Le dauphin est en danger. -- "luh doh-feh[n] eh (t)ah[n] dah[n]-zhay"
...or maybe you meant
The dolphin is going extinct. -- Le dauphin est en voie d'extinction.
its danger
Dangereux is the most common way to say "dangerous", however risqué is also acceptable.
dangereux, dangereuse
yes
Danger
Yes
a pod
Yes.
risque, danger
sans danger
pigs and dophins
bottlenose dolphins