REGIONAL TRENDS

Hawaiian monk seals are found only in Hawai‘i. Their population stretches across the archipelago from Hawai‘i Island, throughout Papahānaumokuākea Marine National Monument, to Kure Atoll. Population trends and threats differ from place to place across this large range.

Several Hawaiian monk seals on a small islet in the Northwestern Hawaiian Islands (Photo: NOAA Fisheries).

The recent positive trend in population numbers was largely due to years of improved juvenile survival in the Northwestern Hawaiian Islands, an important turn-around from previous patterns in this region.

Populations in the main Hawaiian Islands appear to be leveling off after a period of expansion from the 1990s–early 2000s.

While there have been no signs of ecological limitation in the main Hawaiian islands—pupping rates are still excellent for the species and animals appear in robust condition—several anthropogenic threats have the potential to limit recovery of monk seals in the main islands.

THREATS

Threats in the Northwestern Hawaiian Islands include food limitation, shark predation (particularly at French Frigate Shoals), aggressive male seals, and entanglement in marine debris. The "big three" threats facing monk seals in the main Hawaiian Islands are toxoplasmosis, trauma, and interactions with shorecasting fishing gear and lay gill nets.

Hawaiian monk seal rests on the beach entangled in a derelict fishing net (Photo: NOAA Fisheries).