A growing endangered Hawaiian monk seal population around the main Hawaiian islands has prompted the federal government to propose designating areas on and around Hawaii’s most developed islands — and not just in the remote Northwestern Hawaiian Islands — as protected areas or critical habitat for the species.

The number of monk seals from Niihau to the Big Island, where Hawaii’s 1.4 million human population lives, has been rising since the mid-1990s. In 2000, federal officials counted just 45 in the main Hawaiian islands. Nine years later, they counted 113.

“In 1988, seal sightings were really rare in the main Hawaiian islands. It was really seldom that we ever saw them here. But nowadays they’re much more common here,” said Jean Higgins, who is heading the National Oceanic and Atmospheric Administration’s effort to revise the habitat for the species. The government last revised the critical habitat for the animal in 1988.

The seal population is growing in the main Hawaiian islands because they’re giving birth to more pups.

This doesn’t mean the species is thriving in general. In fact, the overall population of less than 1,200 animals is shrinking 4 percent per year, primarily because the survival rate for the species in the Northwestern Hawaiian islands — where they are most numerous — is abysmally low.

This is because still developing juvenile seals in the remote atolls of the northwest are having trouble competing with large predators, like sharks and ulua, or jacks, for food. In contrast, juveniles in the main Hawaiian islands, where there are fewer sharks and ulua, are able to find plenty of food.

All this makes it more important for the government to protect beaches and waters in the main Hawaiian islands where the seals forage for food, rest on the sand and give birth to pups, conservationists say.

“One of the keys to their recovery will be protecting habitat for them in the main Hawaiian islands — because that’s kind of a refuge for where they are going to be thriving the most right now,” said Miyoko Sakashita, a lawyer for the Center for Biological Diversity.

The organization is one of three environmental groups that prompted the proposal by petitioning the federal government to revise the seal’s critical habitat.

Some of the areas proposed as critical habitat — or places deemed essential for the conservation of the species — include beaches and waters of Kauai, Oahu, Maui, Molokai, Lanai, Kahoolawe and Hawaii island.

Coastlines already hardened with features such as seawalls — for example, Pearl Harbor and parts of Waikiki — have been left out. This is because the seals are unlikely to rest,  molt, or give birth at such sites. Other areas, like the Marine base at Kaneohe Bay on Oahu and the missile range facility on Kauai, have been excluded for national security reasons.

NOAA proposed the critical habitat change on Thursday. It aims to hold public hearings on the idea in August, and will accept comments from the public on it through Aug. 31.

If approved, the decision would affect only federal agencies, and the actions that are funded or authorized by the federal government. People and organizations that aren’t funded by the federal government, or those who aren’t operating under federal permits, wouldn’t be affected.