Summer 2019 Breeding

Three kreisels this year.

August 2019. Now that Crab Con 2019 is finally in the rear view mirror (It was a big success!), it’s time to start thinking about the 2019 breeding season. I have yet to observe any mating, but I’ve made a ten-gallon kreisel to have a tank that I can set up for smaller batches of eggs (or for surprise, out-of-season spawns). This way I don’t have to activate the full setup if it’s just a one-off. I also want to see how manageable (and inexpensive) I can make the breeding process, so that someone who wants to give it a go but doesn’t want to go all-in right off the bat will have some options and a simpler road map to follow.

I’ll be keeping the water at 78 degrees this year (last year was 83 degrees) and the salinity at 35 PPT. Also only using one bubbler in each kreisel, just enough to keep things moving. Will be adding nannochloropsis from the start. In fact, if I can get some culturing in the kreisel before the first spawn, even better.

Frederico and Saskia.

August 8th, 2019. I’m pretty certain the Es mated this week (on August 6th). They are fierce little maters! I didn’t get to observe any mating activity last summer, so their mating behavior surprised me and I first took it as aggression. I have a decent hunch as to which of the two males mated with Saskia. I believe, based on follow-up protective behavior, that it was Frederico again. This would put spawning for the Es sometime on or around September 4th.

I have yet to see any mating behavior in my Purple Pinchers and no sign of eggs, although my main breeders are up and active now: Kermit, Lola, Artemis, Garbo, and Blue. It’s fine with me if they wait. If they mate in September, that gives me a little bit of a break between batches. The full moon is still a week away, though, so I wouldn’t be surprised if they “went for it” then. My PPs are pretty reliable full-moon maters.

Having a soak.

As for the strawberries, it’s now 31 days since Abby was observed mating and then was subsequently brought to me to give her eggs a chance to hatch. I’ve seen no spawning, but I did observe her shifting around and acting broody earlier this week. However, that behavior seems to have stopped as of this morning, so I believe Abby dropped her eggs overnight somewhere in the tank. I did a search, but didn’t find anything that looked like eggs. I’m guessing they were consumed by the other crabs. I really wanted this to work first time out of the gate, but straws, as a species, are completely new to me and I still have a lot to learn about their behavior, mating or otherwise.

I’ve also been spending some time thinking about the breeding program in philosophical terms, too, including the bioethics of what I’m trying to do. Also what my long-term goals are, and just generally trying to figure out what I want my role to be in this long-term breeding project. Last year, I tried to induce spawning in Blue when I was sure it was time and she wasn’t going into the saltwater on her own. She was terrified as she went underwater, scrambled out as fast as she could, and then spent hours drying the eggs (which clearly hadn’t been ready after all). Then two days later she cast them onto some wood in the tat and the other crabs ate them. (I gathered some and added them to the saltwater, but none hatched.) I had clearly interfered at the wrong time and I took that as a reminder that I don’t actually know more than nature and that it’s not really under my control–it’s all up to the crabs.

So, I won’t be forcing any human-induced spawning on Abby. I want her to trust me long-term, and we’re still just barely getting to know one another. Plus, I want this whole breeding thing to be a cooperative effort. I want the crabs to WANT to spawn and give me a shot at this. It’s an approach that I believe respects the animal’s role in this whole venture. I need to let her do her part and I need to learn more about her–and straws in general–and I need to remember that this is a process. Do I want straw babies? Heck yeah, but I want them to hatch on their terms.

Does this make me a little crazy in some people’s eyes? Probably. Do I care? Not that much, as it turns out. This is between me and these beautiful crabs I get to care for–and we’ll do it the way that works best for us, but I promise I will give it my all if Abby (or anyone else) gifts me with little baby swimmers.

August 28, 2019 (22 days after mating) and Saskia really, really wants to spawn. She paced and fretted, and never quite got it done. And after three long, anxious days, and two obscenely short nights, I believe she ditched her eggs. I found some and put them in saltwater, but after an hour of vigorous bubbling to revive them, there were only a handful of halfhearted squiggles. I stared for ages trying to isolate them and then moved those few squigglers to the kreisel, but it’s so green with nannochloropsis it’s hard to see if any are still alive. As I was trying to pick them out of the messy water, I was thinking, “Can I really do this again???” It’s so much crazymaking work it’s not even funny. Also, many of the eggs she ditched were clearly unfertilized. They were still small, hard, and a dark orange-red. I’m not really sure what went wrong in the process, but it’s quite likely that this wasn’t a viable batch. I haven’t seen her since this afternoon (after days of restless pacing) so I’m pretty sure she’s all done and hiding to recover. Next up, the PPs.


September 10, 2019 (Day 1!) Scooter, one of my very smallest wild-caught crabs spawned this morning at 4:30am and I got it on video! It isn’t great quality, because I didn’t want to startle her and make her stop, but she’s doing it. She’s quite a young crab (based on her size when I got her—very tiny—I doubt she’s more than four years old) and she spawned absolutely beautifully. Textbook spawn. (This also bodes well for my captive-bred babies to make babies sooner than I thought, in a second-generation breeding.) I’m so proud of Scooter. You can see all the babies swimming in the surrounding water. Here we go again!


September 22, 2019 (Day 13) We have officially reached Stage Three. It’s super overwhelming trying to keep everything running smoothly, especially on shed days, but I’m just going forward one day at a time. They’re beautiful, amazing creatures and I feel honored and grateful to have the chance to help them grow and live and find loving homes someday. And while we’re at it, let’s put the hermit-crab-as-a-throwaway-pet industry out of business.


September 28, 2019 (Day 19) Entering the doldrums (the period of growth I always just have to be patient and WAIT OUT in order to get through). Not much happens for the next week or so, but at least the next stop is Megalopa Town. Their color is filling in beautifully–lots of nice orange bodies and they’re becoming competent swimmers. Many are quite large, too, Stage Five, for sure. Lots of large sheds in the water today. I’m feeding live brine shrimp overnight and that seems to be agreeing with them. They clearly hunt in the dark because by morning there are zero brine shrimp left and the tummies of the zoeae are orange.

Hoo-boy, that’s a lotta eggs, Lola.

October 4, 2019 (Day 26) It looks like Lola was a late breeder this year, same as last year. And holy cow does she have A TON of eggs. That’s a pretty warm spot where she is, back against the heated rear wall, and it’s super protected. Those walls surrounding her are the ribs from a large piece of elkhorn coral in the tank. (You can see where the crabs have eaten away at it for calcium.) I’m currently up to my eyeballs in zoeae, but if she spawns correctly I’ll give hers a chance, too. (She’s not known for spawning correctly.)


October 1, 2019 (Day 22) First megalopa! This is about ten days sooner that last year’s babies.


October 5, 2019 (Day 27) Yesterday I felt like I was finally getting things under control. Patted myself on the back for making it all work. Even made time for a video and an Instagram post. Beware that feeling. It’s a sign that it will soon be time to list A Series of Unfortunate Events:

  1. At 5:30 am this morning I woke to the feeling that I should check on things in the crab room … only to find (first off) that Kermit had shell-jacked the big straw! Yowza. That poor dude was all crammed into Kermit’s shell looking forlorn and a small part of his big pincher (that he had recently molted so perfectly!) was missing. Also, I think one antenna. Gosh I felt so awful. I moved him back to the straw tank with extra goodies and fresh saltwater but he was pretty anxious and just wanted to crouch in the corner. I gave him space and lots of bigger shells and by this afternoon he’d picked an appropriate shell and eaten some. He’s such a big gentle soul and he loves fresh rose petals. I’m going to name him Ferdinand.
  2. Next discovery: the heater in my double kreisel had come loose from the bottom and so it was too warm up against the right kreisel and a whole bunch of zoeae transformed into megalopa overnight and then died (or got eaten and then died). I did manage to save a bunch, too, thankfully, because I was up so early attending to poor Ferdinand. I lost count after 200 but I would guess it’s somewhere in the 300 range. Not saying they all are alive right now, but they were at least when siphoned up.
  3. It’s getting cold here and the house is now way too cool for my brine shrimp to hatch so I have nothing now to feed these bajillion hungry zoeae. I used to do that (last year) in the empty 55, but I can’t do that now with the straws in there.
  4. Lola dropped all those beautiful eggs of hers somewhere in the tank (other than the saltwater pool) and I can’t for the life of me find them. She looks greatly relieved, but I’m sad to have lost a shot at more of her babies.
  5. I have NO IDEA now what to do about the 55 gallon tank with the straws in it. I’m thinking I may have to buy a temporary tank for the straws for about a month while I get this transition tank worked out. I don’t think I can trust my PPs to play nice, especially not now, in the height of breeding season.
  6. On the FORTUNATE side of things, I found a captive-bred baby in the 55 this afternoon!! That little guy has been in there making his way through life since early July, unseen, eating whatever, hanging out with the straws. Crazy crabbies. Mostly, though, I really just want to run away. Anyone care to crabsit 6,000 hungry zoeae?

October 11, 2019 (Day 33) First baby heads for land!

Number Two walks onto land.

October 12, 2019 (Day 34 and Day 1) We had another spawn this morning. Batch two for this summer. And the picture is of the second baby to bravely venture out of the water and onto land from batch one. This little guy’s eyes are super prominent already—see how they are raised up from the rest of his body?—I’m thinking he may have already done his final molt. I don’t think I’ve ever seen them stick up like this on megalopa before, although I’m not entirely sure what that means.

Tiny baby in a larval whelk shell.

October 15, 2019 (Day 37 and Day 4) It’s a shed day for the new larvae, headed into Stage Two. Meanwhile, this little fellow pictured to the right came onto land wearing a very small larval whelk shell that a friend of mine (and fellow hermit crab lover) spent hours carefully removing from a larval whelk egg case that she found washed up on the beach. That’s a grain of sand on my palm above him. In fact, HE is basically a grain of sand, too. If you were sitting on the beach, that’s what this little baby would look like to you — sand.

Number 55 to exit the water and give life on land a try.

October 16, 2019 (Day 38 and Day 5) This adorable little baby climbed all the way up the ramp and found the sphagnum moss that I placed along the sides of the ramp at the top to deter them from walking off the edge and falling back into the water. It’s a mighty climb for these guys, and although I’m sure waves in the wild push and pull them back and forth before they finally get out of reach I didn’t want to make them work THAT hard to get on land. Some struggle? Yes, of course. It’s good for an organism. Too much struggle, especially against Mother Nature? Not so good. Mother Nature always wins.


October 18th, 2019 (Day 40 and Day 7) A quick video of the setups/steps: 1) the first kreisel contains seven-day-old zoeae in larval Stage Two 2) the second kreisel contains much larger Stage Five zoeae going into the megalopa stage 3) the Transition Tank with all megalopa looking for shells and eventually walking onto land, and 4) the babies who have exited the water wearing shells and been moved to land.


October 22, 2019 (Day 44 and Day 11) We have babies on land!


October 25, 2019 (Day 47 and Day 14) These two little dudes in the spiral shell walking along the edge of the transition tank crack me up. I love how they walk, learning to use their new legs. They’re like toddlers. Babies in the water.

Fingertip Baby.

October 29th, 2019 (Day 51 and Day 18) Some of the babies coming onto land this year — especially the later ones, oddly enough — are absolutely insanely tiny like this itty bitty little fellow on my fingertip. I can tell you this: it’s really hard to manage them when they are this small. Hard to pick up without crushing (either with fingers or with a pair of tweezers), hard to transfer to the land tank without dropping, hard to track once you do transfer them.

I also have one who has made the final molt into hermit crab but then walked onto land without a shell. I’ve very carefully reshelled him three times (using a toothpick to lift him and a very steady hand). I fear he may not make it if he doesn’t stay in a shell soon. Not sure why he’s so resistant to wearing a shell, but he climbs right out. Just tried him in a minuscule turbo. Fingers crossed this one holds.

Day 55, babies on land.

November 2nd, 2019 (Day 55 and Day 22). From the first spawn, I’ve now moved a total of 390 from the transition tank to the land tank, and that’s my final count. The second spawn is starting to transition to megalopa as of today and I put about 20 into the (new) transition tank this morning. It’s much smaller because I’m trying to see how little I can do with the second spawn and still get some to land. We’ll see how it goes.

You would think I would be over-the-moon after my success, but I’m actually really feeling strange and struggling to stay on an even keel. That’s so many baby crabs! What if I can’t find homes for them all? What if I’ve just brought more crabs into a system that can’t handle them all? What if no one wants anymore because now it’s not as special as the first time? I don’t know why, but the whole thing is really freaking me out.

You can see the left pincher already getting larger.

I’m feeling so much doubt these past few days. Sure, I set out with the lofty goal of changing the way hermits are bought and sold and valued….but, really, who am I to do that? And organize and run a hermit crab conference?? What was I thinking? I’m suddenly terrified by the weight of all of this. Ugh. Here’s hoping it passes soon.


November 4th, 2019 (Day 24) The second spawn are making megalopa faster today. I moved about 70 more over as this morning, for a total of 90 so far. Here’s a video of the Stage Five zoeae (in the wastewater after siphoning) before making the transition to megalopa.


December 15, 2019: Temporary Update. I plan to come back later and update all the important breeding stats–as well as create a “road map” for others to follow–but the final count for captive bred hermit crab babies moved to land in 2019 is 726 from two spawns. The first spawn yielded 390 and the second, much smaller spawn, yielded 336, so there was a much better overall survival percentage rate for the second spawn. Looking forward to spending time analyzing the data to determine why.