The Papahanaumokuakea Marine National Monument in Hawaii may be home to more unique fish species than anywhere else on Earth, according to NOAA scientists. The Bandit Angelfish (pictured) is endemic to deep reefs located within the Northwestern Hawaiian Islands. In waters 100 to 300 feet deep, nearly 50 percent of the fish NOAA scientists observed over a two-year period were unique to this region, a level higher than any other marine ecosystem region in the world. (Photo : NOAA Headquarters )

The Papahanaumokuakea Marine National Monument in Hawaii may be home to more unique fish species than anywhere else on Earth, according to NOAA scientists.

Hawaiian ecosystems are known as hotspots for biodiversity, but the networks of deep sea coral reefs around around the UNESCO World Heritage site harbor unprecedented levels of biodiversity and highlight the value in protecting the area, the scientists report in the Bulletin of Marine Science.

Papahanaumokuakea Marine National Monument, or PMNM, encompasses an area larger than the size of Greece and includes 10 islands and atolls of the Northwestern Hawaiian Islands (NWHI).

Earlier studies at PMNM have indicated that at depths of 100 feet or less, the region has 21 percent of coral reef fish species unique to the Hawaiian archipelago.

But the new NOAA research that took place in waters 100-300 feet deep revealed nearly 50 percent of species were unique to Hawaii. The study also revealed that in the region's deeper reefs, the percentage of unique species jumped to 90 percent.

"The richness of unique species in the NWHI validates the need to protect this area with the highest conservation measures available," said Randy Kosaki, PMNM's deputy superintendent and co-author of the study. "These findings also highlight the need for further survey work on the monument's deeper reefs, ecosystems that remain largely unexplored."

In addition to the the Bandit Angelfish (Holocanthus arcuatus) pictured above, other speices unique to the region's deep coral reefs are Redtail Wrasse (Anampses chrysocephalus), Thompson's Anthias (Pseudanthias thompsoni), Potter's Angelfish (Centropyge potteri), Hawaiian Squirrelfish (Sargocentron xantherythrum), Chocolate Dip Chromis (Chromis hanui), Masked Angelfish (Genicanthus personatus) and Blueline Butterflyfish (Chaetodon fremblii).