Why is bull kelp necessary?

Why is bull kelp necessary?

Tuesday, July 23, 2013

Log booms mowing down bull kelp canopies

In an effort to understand why an important canopy-forming kind of kelp is in rapid decline around Gabriola Island and elsewhere, Help the Kelp has been mapping with GPS units all bull kelp around the island. Later in the summer and throughout the fall and winter months the team will be "replanting" with various techniques to see if we can densify existing beds.

While mapping around the south-western side of the island last week, team members Liam, Michele and Michael examined the area around many large log booms. You'll see from this map produced that bull kelp is quite healthy through False Narrows but then declines rapidly near the log booms directly across from the Harmac kraft pulp mill.

Of course there are many possible reasons why bull kelp is in decline including warming waters, predation, etc., but one possible explanation is that log booms seem to be mowing down canopies. We noticed while mapping that log booms create zones of death around them. As someone who has scuba dived underneath them at nearby Valdes Island, I can testify that the normally rich ecosystems below have been decimated. This photo is an example of dead kelp around log booms.

You will note that the log booms are filled with bull kelp as well thus indicating that the practice of towing log booms across sensitive ecosystems is far too prevalent. It is time for action!

1 comment:

Anonymous said...

Education is key. This loss of kelp ecosystems is so preventable. Log booms travel where they are pulled. The kelp floats helpfully signal the underlying beds making avoidance easy. The actual areas are small, often near shore and their location are predictable and now mapped out. Who do we need to tell?