Thursday, 31 December 2015

changes: urchins, kelp, dolphins, orcas

Green urchins dominate the bottom in large areas.  This is a patch in Q Cove. In the extreme these are called urchin barrens, and appear to result from the Sea Star Wasting Syndrome which killed most of the starfish from California to Alaska.  The sea stars ( starfish is the old term ) would be a top predator on the bottom and kept everything in balance. I've posted about this before, but now the cause is know to be a virus. The sea star population seems to be coming back.

Kelp has disappeared from many areas because the urchins graze it off before really gets started growing. This photo shows a kelp patch holding on in November. Bull kelp is an annual plant. 
Although there are many local spots where the kelp forests have disappeared such as locations in Georgia Strait, there are other exceptional examples. I have noticed that on the south side of Race Point to Middle Point in Discovery Passage, the usual extensive kelp bed was gone this year, but on the north side of Race Point into Menzies Bay, the kelp bed was wide and strong as usual.  
 The most unusual thing was the several kelp stems that appeared in the Tyee Pool, on the south part, near the Can Bouy. That was a new thing, and a set of challenges for rowing  precious lures around. 

 The Pacific White-Sided Dolphins have become a regular sight in summer. I think that it is a newer development to see them often in winter. Here is a gang in November in front of the Tyee Club clubhouse,( which is closed until the rowing season begins July 15 when the big chinooks come home. ) 
Also note how tall the boat houses appear in the background due to high winter tides and high river level in the river . 

These Orcas ( Killer Whales ) are likely looking for seals in the mouth of the Campbell River. This is  November.  These are the mammal eating type of  orcas, which have been called Transients but are re-named Biggs Orcas. In recent years they have stayed in the general neighborhood all year round, but they move around a lot to ambush their prey, which include seals ,dolphins, and porpoises. 

No comments:

Post a Comment