Kelp Mapping Project
September 29, 2016
Augusst, 2016 volunteers from PICA helped with an ongoing kelp mapping project being run jointly by Sea Change and University of Victoria. Bull Kelp (Nereocysitis luetkeana) is a large seaweed that comprise large underwater forests in coastal waters from Alaska to California, and are common to the Gulf Islands and the Salish Sea. They are very important to the ecosystems of the coast as they provide habitat to an incredible variety of organisms, from plankton to crustaceans, snails to small salmon, sea otters to waterfowl. Unfortunately, bull kelp forests are vulnerable to changes in the ecosystems in which they live. They are negatively affected by changes in temperature and salinity of the water, increased silt and toxins in runoff and an increase in creatures that feed on the kelp. (Declines in sea otter populations in the past and the current collapse of starfish populations have lead to a great increase in the numbers of sea urchin, who love to munch on kelp).
It appears that the kelp forests in the Salish Sea are declining; the beds are fewer and more sparse. This is of great concern, but there is little data about the previous sizes of kelp beds other than anecdotal observations of long time residents of the area. In order to reliably measure the changes in kelp beds, base line data has to be obtained. Mayne Island Conservancy and other volunteers have been mapping out and monitoring kelp beds around Mayne for six years now, using a combination of satellite photos, and on-the-water- mapping using hand held GPS devices. But there is no reliable evidence regarding kelp beds around Pender.
To that end, a small handful of volunteers, led by researchers Leanna Boyer from Sea Change and Sarah Schroeder from the University of Victoria, went out at low tide in canoes and kayaks. Armed with GPS devices and weighted tape measures we sought out and mapped kelp beds in the waters around Pender Island. Since we could only map for an hour on each side of lowest tide, it took three days (kelp beds are easier to see at low tide, and sticking to this timetable allows for standardization in data from other areas and years of mapping). Unfortunately we were unable to cover all the known kelp beds, but it was a good start. Hopefully, we will get more volunteers next year and will be able to cover more ground—um...water.
According to Leanna, the kelp mapping was a great success, and it is hoped that it will continue in years to come under the leadership of community volunteers. For more information check out the link at conservancyonmayne.com/kelp.php.