kelp devastation at Coral St

[dshorwich]

We did a Reef Check survey at Coral Street yesterday (6/13), and when I pulled up to the site in the morning I was very surprised to see that the kelp mat, which ought to be fairly substantial by this time of year, was virtually non-existent. There was one small patch of giant kelp off at the far northeastern end of the site, and a few stray plants in the protected area of the shallows, but other than that - nothing.

When we got down there to do our surveys, it wasn't hard to figure out what had happened to the kelp: urchins, mainly purples but also reds, were extraordinarily abundant. We ran 6 algae surveys, each one covering a 30m x 2m box; on those 6 surveys, we found a grand total of 1 giant kelp plant, a smallish one at that. Meanwhile, we were finding urchins in the 100s on our invertebrate surveys, they were just littering the site, all over out in the open. Our surveys cover only a portion of the site, so extrapolating the numbers we recorded yesterday, there must be literally thousands of urchins at that one small site. You'd need an armada of otters to deal with them.

Does anyone know if this urchin devastation of Coral St is a recent event? I hadn't dived the site since last November, so I don't know whether the kelp bed had been growing normally earlier this year, or whether it never got started this year. Has anyone seen anything similar at other sites around the bay? I saw unusually abundant urchins at Pt Lobos in late March, but the kelp wasn't entirely gone as it was at Coral St yesterday.

 

[Ongrade]

I was there about 2 months ago and it was still abundant. I'd guess the starfish die off has allowed the urchins to run wild. Saw huge numbers of urchins in Carmel bay 2 weeks ago, kelp chewed down to 3-4' stalks on the bottom and covered in urchins. But I did see more live, healthy starfish than last year so maybe they'll come back and deal with the urchins.

 

[dshorwich]

I was there about 2 months ago and it was still abundant. I'd guess the starfish die off has allowed the urchins to run wild. Saw huge numbers of urchins in Carmel bay 2 weeks ago, kelp chewed down to 3-4' stalks on the bottom and covered in urchins. But I did see more live, healthy starfish than last year so maybe they'll come back and deal with the urchins.

Thanks for the info that the kelp was intact a couple of months ago. The outbreak of Sea Star Wasting Disease may well have something to do with it, although that first cropped up in the fall of 2013. I have seen more giant-spined stars around this year than last, but sunflower stars are still extremely thin on the ground, as far as I know.

 

[Ongrade]

I haven't seen a sunflower star this year, been to Carmel River, Lobos Rocks and all around Cypress Point area this year, 25 or so dives.

 

[Keith.M]

Keep your eye out and think small... The large ones all seem to have died off. But if you go slow and look, you can usually spot some small sunflower stars. I am hoping they make a come back.