Beach vacationers in Nags Head, North Carolina, struggle to keep a sperm whale from beaching itself. Sadly, two beached sperm whales that day — a mother and calf — were eventually euthanized by representatives from OBX Marine Mammal Stranding Network.

We scuba divers love our encounters with the oceans’ four groups of marine mammals: cetaceans (whales, dolphins and porpoises), pinnipeds (seals, sea lions and walruses), sirenians (manatees and dugongs), and marine fissipeds (polar bears and sea otters).

Marine mammals are just like us: They breathe air through their lungs, are warm-blooded, have hair (at some time during life), bear live young, and produce milk to nurse their young. But what sets them apart is that they possess unique physical adaptations that allow them to thrive in water, including being able to withstand extreme ocean temperatures, depths, pressure and darkness.

There are many threats facing marine mammals today, including three that can cause injury or death — accidental or deliberate stranding, entanglement and toxic pollution from an oil spill. In these cases, it’s natural to want to help the animal. We’ve laid out guidelines so you’ll know what to do if you encounter a marine mammal that needs your help.

Step No. 1: Report marine mammals that appear to be ill, abandoned or in danger. Many states and countries have a stranding network of experts, including veterinary specialists, who are specially trained in how to deal with marine-mammal emergencies.

TO HELP A STRANDED OR BEACHED MARINE MAMMAL

Sometimes, marine mammals will strand themselves deliberately, due to illness, or accidentally, often for unknown reasons. Note: Seals and sea lions regularly “haul out” of the sea to rest on the shore, and pups are often left alone by their mothers. If you approach too closely, the mother may be scared off and abandon the pup.

• Immediately call for expert help. NOAA responds to stranded marine mammals and works with volunteer stranding networks in all coastal states.

• Observe the animal from a distance of at least 50 feet. Keep people and dogs away; they can stress the animal. Observing from a distance allows you to see whether this is a temporary, deliberate “beaching,” as in the case of a seal or sea lion. It also allows you to communicate important information to experts who can help.

• Determine the species. If you don’t know it, describe physical characteristics such as size, markings, external earflaps and fur color. This helps rescuers determine the species, so that they know what rescue equipment and volunteers are needed.

• Describe the animal’s condition. Is it weak or suffering from any open wounds?

• Provide the exact location of the animal in order to provide accurate directions.

• Whales and dolphins often strand on their sides. If expert help is not available immediately, approach cautiously and calmly. Gently roll the whale or dolphin onto their front (belly), so that the blowhole is facing upwards. It is helpful to keep their skins wet with water, but be very careful not to get water down the blowhole. If you can talk to an expert on the phone, they can guide you.

We’ve published amazing stories about divers and snorkelers who have disentangled an injured whale shark, dolphin and humpback whale, but it can be dangerous to both the animal and rescuer. What can you do if you spot an entangled marine animal?

• Call the experts, even when you spot a marine mammal who is entangled underwater. Highly trained emergency responders will be able to disentangle large whales. These animals are very powerful and often in pain.