At last, a publication on the causative agent for sea star wasting syndrome! Several co-authors have written a paper that was published in the Proceedings of the National Academy of Sciences (PNAS), in which the culprit was identified as a densovirus. The Smithsonian wrote up a nice article summarizing the findings here. While it remains…
Marine invertebrates
Monsters in the making
Yesterday I collected three very small Pycnopodia helianthoides stars. When I brought them back to the marine lab I decided to photograph them because with stars this small I could easily distinguish between the original five arms and the new ones: These guys began their post-larval life with the typical five arms you’d expect from…
The road to recovery, perhaps?
“Perhaps” being the operative word here. I was up at Davenport Landing the other day to do some collecting, and saw some healthy stars. Alas, no pictures, as I’m not coordinated enough to do photography and collecting on the same trip. But here’s what I saw: 5 healthy Pisaster ochraceus stars. This was the first…
Wasting disease in subtidal stars
Since my earlier posts on Pisaster wasting disease in the lab, I’ve been contacted by a couple of divers who have seen afflicted stars on their dives in Monterey Bay. They have both graciously given me permission to post their photos, which clearly demonstrate that Pisaster and other stars are being stricken subtidally as well as…
The last days
Well, it looks like the end is indeed nigh. That last Pisaster, for whom I held out unreasonable hope for so long, seems to be on its way out. Today it has lost its last two arms, leaving a central disc attached to a single arm: As bad as it looks, it could be a…
Well, maybe not
Against all odds, my last Pisaster star is (literally) hanging in there. It hasn’t lost any more arms in the past 24 hours, and by the standards of the past two weeks that’s a rousing success. And it hasn’t lost the turgor pressure of its body, so it isn’t as limp as the others were…
And then there were . . . none
The last of my Pisaster ochraceus stars waited until today, three whole days after all of its conspecifics had died, to start ripping itself into pieces. This is the sight that greeted me when I checked on my animals this morning: I spent some time examining the severed arm because it is freakishly fascinating to…
A plague of stars
And I don’t mean plague as in “too many stars to know what to do with,” but as in “disastrous sickness that you don’t want to catch.” Some of the stars in my seawater table have been succumbing to some awful disease lately. A week ago today I noticed that many stars had been busy…
Motherhood, snail style (Part 2)
It has been almost a month since my big female whelk started laying her eggs, and the embryos seem to be developing nicely. The first time I witnessed this phenomenon I saw the egg capsules begin to turn black, and worried that the eggs inside were dead and decomposing. But the cool thing about Kelletia…
Motherhood, snail style
This week my female Kellet’s whelk (Kelletia kelletii) started laying eggs. She’s been doing this every summer for the past several years. She lives with one other whelk, presumably the father of her brood, as the eggs are both fertilized and viable even though I’ve never seen the snails copulating. That’s right, copulating. Whelks are…