Rising seas top threat to Northwestern Hawaiian Islands

When researchers looked into the most significant threats to the Northwestern Hawaiian Islands, the top threat was a slam dunk: rising seas.

That’s because most of the islands of the northwestern end of the Hawaiian archipelago are low, sand and coral islands. A foot of sea level rise could erase entirely much of the dry land.

(Image: A map ranking human impacts in the Northwestern Hawaiian Islands. From

http://www.hawaii.edu/himb/nwhi)

And with that, the stunning repercussions for wildlife: Something like 90 percent of all the Hawaiian green sea turtles nest on the sandbars of French Frigate Shoals; entire species of seabirds and a few land birds rely on these specks of land for nesting habitat; Hawaiian monk seals, already threatened, would lose their haulouts and pupping places.

This threat research is documented at a new website, which documents research being done in the Northwestern Hawaiian Islands. Those islands, which lie beyond Kaua`i and Ni`ihau, are managed as the Papahānaumokuākea National Marine Monument.

“Those interested in the exciting and dynamic research coming out of HIMB now have an easy to use forum and site to access information,” said Robert Toonen, principal investigator for the HIMB Northwestern Hawaiian Islands Research Partnership.

The website has gone “live” this week.

Just one of the pieces of research on it involves the mapping of cumulative impacts of human activity. The team talked to 25 experts about the various threats, and ranked them.

We used a novel index of ‘ecological vulnerability’ that accounts for five ways a human activity can adversely impact a coral reef: the area and frequency of impact, the number of species impacted, the biomass lost and the recovery time following the impact,” the site says.

From the biggest threat to the least problematic, here’s how the ranking went:

Sea level rise, sea temperature rise, marine debris, alien species establishment, increasing ultraviolet radiation, ghost fishing, sea water acidification, ship groundings, coastal engineering, land-based runoff, ship waste input, pelagic long-lining and net fishing, anchor damage, lobster trap fishery, research wildlife sacrifice, sport fishing, trampling damage, vessel strikes, diver impacts, research manipulations, bottom fishing, indigenous fishing, aquarium collecting, and non-fishing non-diving recreation.

The report said that while the islands are protected from many direct human impacts, global threats put them at serious risk.

© Jan TenBruggencate 2011