Aboard US Coast Guard HC-130 Hercules - A United States Coast Guard HC-130 Hercules rumbled down an airstrip on Hawaii's Big Island on Thursday carrying seven endangered Hawaiian monk seals.The young monk seals were found abandoned or malnourished late last year by National Oceanic and Atmospheric Administration officials in the uninhabited Northwestern Hawaiian Islands. They were rescued, then rehabilitated at the non-profit Martine Mammal Centre's monk seal hospital in Kailua-Kona, Hawaii, where the Coast Guard picked them up on Thursday for the first leg of their journey home.NOAA found six of the seal pups on the remote Northwestern Hawaiian Islands, the northernmost islands and atolls in Hawaii. The seventh seal, a yearling, was rescued from Niihau, a privately owned island in the main Hawaiian Islands.The Marine Mammal Centre's monk seal hospital on Hawaii's Big Island then nursed the animals back to health.On Thursday, the seals were loaded into a US Coast Guard plane and flown from Kailua-Kona, Hawaii, to Honolulu.According to the California-based Marine Mammal Centre, fewer than 1 in 5 monk seals survive their first year in the Northwestern Hawaiian Islands because of threats including predation, entanglement and environmental changes. There are only about 1 200 monk seals in the world, NOAA officials said, and they all live in the main or northwest Hawaiian islands.The seals being transported on Thursday were all females, said Michelle Barbieri, a NOAA veterinarian with the Monk Seal Research Program who was aboard the flight."We focus our efforts on female seals because they're going to grow up and contribute to the population in the future," Barbieri said.While in rehabilitation, the seals were slowly nursed to a healthy weight to help increase their odds of survival. They were also taught to catch and eat fish naturally, with little human intervention, so that they could hunt for themselves when they return to the wild.David Scholfield, a NOAA response co-ordinator for the Pacific Islands, said rescuers normally transport only one or two seals at a time, making Thursday's effort "historic" and a major boost for the overall population in generations to come.The monk seal population is still declining at a rate of about 4% per year. Returning these animals to their home islands could have a big impact, he said."These seven animals would have died," Scholfield said, "and so getting them back to health and having them potentially reproduce in the wild, and produce offspring, has a many magnitude effect" on the overall population.