In today’s Academic Minute, Dr. Howard Lasker of the University at Buffalo explores how coral reefs respond to natural and man-made damage.
Howard Lasker is a professor of evolutionary biology and ecology at the University at Buffalo. His current research project seeks to identify parameters for identifying coral populations that should be highly protected as well as those for which managed harvesting is ecologically sound. He holds a Ph.D. from the University of Chicago.
Dr. Howard Lasker – Coral Damage and Growth
My research focuses on how little and not so little disruptions can affect coral reefs. Long before Super Storm Sandy slammed into New York, Hurricane Sandy swept over parts of The Bahamas. The effects that hurricanes have on people, understandably captures our attention, but events like these also affect the oceans.
Seemingly cataclysmic events like hurricanes are not necessarily disasters for coral reefs, but when they are too strong or occur too often they can have long term effects that go beyond the immediate damage. Even small disturbances can have longer term effects. To examine those long term effects, my graduate student Christopher Page and I went to The Bahamas to study a coral species called Antillogorgia elisabethae. This species is harvested for a chemical used in skin care products, with divers removing branches from large, mature coral colonies. Such harvests took place in 2002 and 2005, and Chris and I returned to the site in 2009 to take a look at how the coral were doing. What we found was a surprise.
When we compared tissue samples from colonies that had been pruned to colonies that had not, we found that pruned female colonies were producing low numbers of eggs and male colonies were producing fewer sperm. This tells us that it can take longer than previously thought for corals to bounce back from injury — even if they no longer look damaged. One reason for the slow recovery may be that damaged colonies divert resources that would normally be used for reproduction toward growth and repair. We correctly worry about the immediate effects of events like hurricanes on reefs, but we now have a more nuanced picture of their effects. Those big events as well as much smaller disturbances have negative effects which are not obvious to the eye but add to the stresses coral reefs are facing.