Tuesday, July 21, 2009

Myriad of Births

"Update more frequently" . . . HA! Well, at least my dad gave my fiancee his decent point-and-shoot, so I no longer have an excuse to not take pictures.

My former professor returned from Arizona with a handful of Vaejovis spp., the largest of which appeared to be a heavily gravid V. spinigerus (or Hoffimanus spinigerus, if you're in the Soleglad and Fett camp). More on her later.

Two weekends ago I was preparing to leave for a family reunion. Friday afternoon I checked on one of my U. mordax females (collected May 1 with professor et al) to show a visiting guest, only to discover she had given birth. Returning home on Sunday evening revealed two more from the same trip had followed suit. By Friday, all four collected May 1 were carrying broods. A quick check also revealed that the large Vaejovis from Arizona also had a pile of young on her back.

Based on the one brood I experienced last summer, I estimated that the first of this year's would molt to second instar on Monday (yesterday). I surprised myself by being correct.

First brood discovered:

Molting to second-instar yesterday morning:

Second brood discovered:

The general consensus is that first instars are doomed without mom. This little guy from brood #2 decided to prove that wrong. He's still fine after having been away from the burrow for four days.

Third brood discovered (this female sealed herself in and burrowed to the bottom of the tank -- fortunately she cleared out an area against the bottom so I could photograph her):

Fourth brood discovered:

And the Vaejovis -- this species is known for having broods of 60 or more young.

In addition to all of these, I have three more female U. mordax. Two of these look like they may be gravid. One spent all winter with a male (recently died, assumed to have been old age) and one was collected at the end of last summer from Detroit. I'm fairly sure that populations from the Cascade Mountains give birth later in the year than those collected in the Coast Range, so we'll have to wait and see what she does.

I also have a friend whom I gave a female on another collecting trip in May. He told me she's looking fatter, and I suspect he'll give me any offspring rather than deal with them himself. Current estimate of young in my possession is 160; if I get young from the other females, my estimate would rise to 235.