So, I made a third update some weeks ago but found out I never posted it, so here it goes…
UPDATE 3 – May 3, 2019
The females had been separated from the males for about two weeks now as I observed both females being copulated with and, according to other successful breeders, mating is wrapped in in a two week period. Though both weight and girth were increasing on both females, I felt extremely paranoid that breeding was not over and pulled them out prematurely (no pun intended). After searching through Internet forums and FB posts, it did appear that I may have separated the sexes too early. A few successful breeders commented on some of my posts how they usually separate mid-May, or when the female appears to be gravid.
So, I figure better safe than sorry and put the pairs back together. What also came out of this was the insight that Gilas become pairs, meaning that success can be enhanced by putting two “known” pairs together and that they will successfully breed together in the future without male combat or by cycling through male cages. I cannot comment on this but it does seem that certain Gilas do pair together and prefer one another. In my example, Gila 01 and 05 successfully mated and remained close together whenever introduced to each other. Conversely, Gila 01 and 03 were not close to each other though they did successfully mate. The same with Gila 04 and 05, though 04 did not mate with 05 and they were always on opposite sides of the terrarium. Gilas 06 and 09, both males, stay home without dates this year. Gila 06 remains quarantined while 09 was not preferred by either females despite his most earnest effort.
After re-introducing Gila 03 and 04, Male 04 wasted no time in getting to it. Unlike earlier in the season where the males chased the females and copulation took place later, this interaction was direct and immediate. Though I suspect that 03 was already gravid I think it was good for him to actually copulate this season; he began eating again after he sowed his wild oats. His activity level also calmed a bit after having his girlfriend back in his territory. I observed copulation with this pair four more times while 01 and 05 did not hook up again though they remained close together.
I will separate the pairs on May 11 as I am pretty sure the females are gravid, but want to be sure. It is fascinating to me how the Gilas know one from another and have different choices in mates. In the wild it is reported that Gilas visit the same dens to breed year after year. Not sure of the same lizard if there each time, but think it means they are familiar with the area and hope to find an old flame that they previously has a successful connection with.