Notes from a Scientist: Dr. Chris Harley

Dr. Chris Harley in the intertidal zone of the
Pacific Northwest

Climate change is a big field of study these days and many researchers are trying to understand what the future has in store with abrupt warming occurring. Dr. Chris Harley, a biologist at the University of British Columbia, is one of many scientists studying how organisms adapt to climate change in the oceans. His focus is on the small intertidal creatures that find themselves sometimes above the water and sometimes below the water, always at the mercy of the tides.

When asked why he works in the rocky intertidal zone, Dr. Harley's immediate response is that: “It's pretty, who wouldn't want to work there?” Elaborating, he explains that the intertidal zone is a great place to work because of the animals. Dr. Harley appreciates that in the intertidal zone you don't have to wait for decades for an area to mature, like you would if you studied forests: off the west coast of British Columbia, barnacle patches can grow in just 6 months. He also points out that removing 100 barnacles on the shore for a study is easier –on both the fingers and the conscience – than removing a 100-year old tree.

Acorn barnacles, Balanus glandula, in the intertidal zone support a community of organisms

Currently, Dr. Harley examines how intertidal animals and communities respond to increases in temperature and increases in carbon dioxide (CO₂). Both of these factors affect how organisms live in any environment and in the intertidal zone both are predicted to change greatly in the coming decades. As temperatures rise, the animals are pushed beyond their thermal limits. As CO₂ enters the water, the pH drops and the water becomes more acidic, subjecting the organisms to additional stress.

To shed light on this problem, one of Dr. Harley's graduate students is raising sea urchins in different water treatments to see how well the animals can form their shells in acidic conditions. This is done by bubbling CO₂ into the water in the lab. In the coming year they hope to test this on the shore at the Bamfield Marine Sciences Centre, but are still working out the details on how to run the experiment, without the tide carrying their research out to the sea.

Sea urchin, Strongylocentrotus droebachiensis, on a tide pool

Although scientists have discussed and argued the occurrence of global warming for several years, many say the time for debate is over. When I asked Dr. Harley how he deals with such attitudes he says: “Those people are just misinformed or have their own agenda. Within the scientific community, the debate on whether it is happening or not is over. What all the causes are and the impacts will be, may still be discussed, but it is happening.” He reminds us that many theories in the past were not fully accepted at first, but as more and more people learn the new science, the debate fades, just as it did when the idea of a round earth and the theory of plate tectonics were first proposed.

If he didn't work along the rocky shoreline, Dr. Harley says there are a few other areas that he would have liked to try out. But at 6'8”, he does not fit well into submersibles so deep sea adventures are not really an option, and he gets the chills quickly so scuba diving in the Antarctic ice water was also ruled out. Luckily for us we find him in the intertidal zone with barnacles, mussels, and other amazing living things. His projects will help us improve our understanding of the marine environment and our impacts on it. As Dr. Harley points out: “the more we know, the better we can predict what will happen in the future, and protect those areas that need it most.”

Pisaster ochraceus, the ochre star, an important intertidal species in the Pacific Northwest

As we finish up our discussion about climate change and marine science, Dr. Harley has two parting messages. The first is climate change is happening and that it is going to have huge ecological implications for the world. Despite this warning, Dr. Harley believes that everyone can participate in preventing this ecological disaster by doing small things everyday. His second message is that ecology, the study of how organisms interact with their environment, is fun. Studying how relationships in nature fit together can yield lots of information and the more we know the better we can make decisions regarding the future of our vital ecosystems.

For more information on what Dr. Chris Harley and his students are doing visit his website www.zoology.ubc.ca/~harley/.

Climate change in the intertidal zone: lesson plan