Good news for coral reefs around the world. New research on the state of Hawaiian coral reefs and their relation to human activity over a 700 year time span shows that even strongly degraded reefs can recover, with the right conservation efforts.
Coral reefs on the Hawaiian mainland have shown periods of decline and recovery. According to new findings presented in the journal PLoS ONE, these fluctuations in the state of the reefs can be attributed to changing human activities.
Fluctuations in reef state
Over 700 years ago reef derived protein sources were the most important for Hawaiian settlers for several hundreds of years, putting tremendous pressure on the surrounding reef ecosystems. However when domesticated animals were introduced to the islands around the 1400s, inhabitants started to eat meat instead of fish.
This change of habit combined with new conservation efforts allowed the reefs to recover. Over 400 years later when The Hawaiian population had intensified land exploitation, reef decline kicked in again due to pollution and changes in demography.
This decline has sustained until present day due to human impact, with a brief let-up during World War II when near-shore marine activity was decreased. Coral reefs in the Northwestern Hawaiian Islands however have begun to recover since World War II due to human depopulation.
A fluctuation in the state of coral reefs as presented in the study shows that direct human-environment interactions have to be included when looking at degrading factors influencing coral reefs.
But most importantly it is a sign that there is hope for coral reefs around the world. As opposed to current believes, deleterious human impact on coral reefs does not necessarily lead to cumulative degradation. With the right management of coral reef ecosystems even the most degraded reefs might be brought back to health.
Combine this with the earlier discovered early warning system and all we need is the will to implement the needed changes to coral reef management, which unfortunately may be the biggest hurdle to take.
© Jorn van Dooren | www.bitsofscience.org