**If you are looking for the hermit crab dishes I make and sell, you can find them at my Etsy store. Thank you!
I’ve had a hermit crab obsession for a while now. And it actually started back in the 1990s when I lived in Florida and bought my first three. I did keep them in a big aquarium, but only provided gravel, a shallow freshwater dish, and pellets of “hermit crab food” from the pet store. I think they lived about two years. And it haunts me.
I have learned so much more about their care and feeding since that time and I like to think I’m making up for my earlier ignorance. These days, my tank is a 120-gallon (tall) with saltwater and freshwater pools, lots of climbing structures, and ten inches of sand—lots of space for them to dig tunnels and create safe molting caves. AND, I’m doing my best to learn how to breed them in captivity so that our pet hermits that we love don’t have to be captured and taken from the wild. Links to detailed records of my captive breeding attempts by year are below, with an FAQ page, followed by a running log from the current year.
BY-YEAR BREEDING STATS:
First Mating (observed): August 15th, 2018.
First (successful) Spawn (September 13th): Approximately 10,000 zoeae hatch successfully and are moved to a kreisel tank kept at 83 degrees Fahrenheit and at a salinity of 35 PPT.
Day 5, first zoeae molt into larval stage two.
Day 9, first zoeae advance to larval stage three.
Day 14, larval stage four begins, about 1,000 surviving.
Day 19, molt into larval stage five begins.
Day 24, first megalopa! (Approximately 40 megalopa get moved to the transition tank.)
Day 36, first megalopa takes a shell and walks out of the water. (Over the next two weeks, 4 are moved to the land tank, in shells.)
Day 49: Confirmed! 2 survivors make the first molt to become land hermit crabs.
Second Spawn (October 16th, 2018): About 10,000 zoeae hatch successfully.
Day 4, zoeae enter larval stage two.
Third Spawn (October 20th, 2018): Another 10,000 hatch, get placed into several small “holding” tanks and receive minimal care. Survivors are gradually added to the kreisel over the next seven days.
At this point, with two full spawns, four days apart, it becomes impossible to tell the larval stages because shedding occurs daily.
Day 23, first megalopa. Over the next two weeks, about 1,000 megalopa are moved to the transition tank.
Day 26, spot blue zoeae among the orange zoeae. Conclude, with the help of other hermit crab experts, that the blue ones must be Ecuadorian zoeae. (This is later proven to be a false assumption.)
Day 34, first megalopa takes a shell and walks onto land.
By mid-December 2018, 240 baby hermit crabs have been moved to the land tank where they are largely cared for similar to adult hermits.
January 8th, 2019: confirm, by count, that 206 have survived the first land molt to become land hermit crabs. (2 stayed hidden in shells and were accidentally left out of the tank after the counting process, so 204 is the actual survivor count, allowing for human error.)
October 22, 2019: 180 captive-bred baby hermit crabs have been successfully adopted out to brand-new forever homes. All of these first adopters have agreed to participate in a long-term study to track growth, behavior, shell preference, and coloration over time and in different conditions.
I’m so very grateful to all those who contributed supplies, love, and support. ❤️❤️
First (successful) Spawn (September 10th, 2019): About 10,000 zoeae hatch successfully and are moved to a kreisel tank kept at 78 degrees Fahrenheit with a salinity of 35 PPT.
Day 22, first megalopa! (Over the next few weeks approximately 4,000 megalopa are moved to the transition tank which is a plastic bin holding roughly 4″ of saltwater at 35 PPT and kept at 75-78 degrees Fahrenheit.)
Day 30, first megalopa takes a shell.
Day 35, first baby walks onto land. Over the next two weeks, 390 megalopa take shells and are moved to the land tank (100% sand) where they will fend for themselves.
Second (successful) Spawn (October 12th, 2019): Approximately 7,000 zoeae hatch successfully and are moved to a kreisel tank. This batch will be given minimal care in an attempt to see how many survive with fewer feedings and water changes.
Day 18, first megalopa! 930 megalopa are moved to the transition tank over the next 11 days.
Day 26, first megalopa takes a shell.
By Day 66, 336 megalopa from the second spawn have taken shells and been moved to the land tank for a total of 726 captive-bred baby hermit crabs moved to land (from two spawns) in 2019.
May 6th, 2020: A follow-up count of the 2019 spawns reveals that 633 of the 726 initially moved to land have survived ~8 months post-spawn. Of that number, .3% are XL (7-8 mm opening shells), 9% are Large (5-8 mm opening shells), 43% are Medium (3-5 mm opening shells), and 47% are small (2-3 mm opening shells).
5-4-20 I meet fellow hermit crab keeper Kelly Kurtz and she gives me three large mason jars of zoeae that she discovered in her saltwater pool and believes to be either C. viola or C. perlatus based on brooding behavior exhibited by her female crabs.
5-7-2020 (Day Five) First day of sheds, so larval stage two begins. They don’t seem very happy, so after researching salinity in the waters off the coast of Indonesia (where I believe these crabs may be native) and finding that it is far more dilute, I gradually lower the salinity to 31-32 PPT.
5-10-2020 (Day Eight) Second sheds into larval stage three begin. They are ravenous and eat everything, but don’t appear to be especially cannibalistic. Still not appearing super happy, so I lower the water temp to 84 degrees Fahrenheit and that seems to be better.
5-13-2020 (Day Eleven) First larval stage four sheds begin, somewhat overlapping with the later sheds to stage three. I believe this will be their final stage, since by now I’m pretty convinced these are not clypeatus.
5-16-2020 (Day Fourteen) I do a full clean and count zoeae as I siphon. There are ~1,400 stage four zoeae on Day 14.
5-18-2020 (Day Sixteen) First megalopa moved to transition tank. Over the next eight days, 1,113 megalopa are moved to the transition tank. They are ravenous and eat anything I give them: frozen brine shrimp, hatched artemia, shrimp pellets, dulse, Marine Snow, and I add plenty of nannochloropsis to the water. I lower the salinity to ~30-31 PPT and the temperature to 81 degrees Fahrenheit so they don’t develop too quickly.
5-23-2020 (Day Twenty) the first megalopa take shells and walk onto land.
6-8-20 All of the surviving megalopa have taken shells and 507 have been moved to the land tank. Stay tuned! (Species STILL UNKNOWN.) Coenobita mysteriosa for now.
9-8-20 At six months of age, all C. mysteriosa are moved to the 55 gallon baby tank (to reside with the remaining 2019 clypeatus babies). It takes two weeks for all molters to resurface and be counted. A full count reveals there are only 275 survivors (out of 507). This represents my highest loss rate to-date (~46%) for any moved-to-land juveniles. I believe this high loss rate resulted from offering access to deep water pools right away. Even with exit ladders many drowned and more became trapped under the pool and expired there. There are no plans to repeat that experiment with future spawns.
9-21-20 Artemis (C. clypeatus) spawns on her own in the saltwater pool.
9-22-20 Gilda (C. clypeatus) has an assisted spawn (in a bucket with a bubbler).
9-24-20 Lola (C. clypeatus) has an assisted spawn. I this point, I have all three kreisels up and running and several tens of thousands of zoeae.
10-4-20 Saskia (C. compressus) has an assisted spawn in a bucket with bubbler, and approximately 6,000 hatch. The C. compressus zoeae are then divided among the three active kreisels containing clypeatus. Given their much smaller size, I believe it will be easy enough to distinguish compressus zoeae from clypeatus.
10-10-20 Big Red (C. perlatus) has an assisted spawn in the prepared transition tank (intended for the upcoming C. clypeatus megalopa but as yet unoccupied). The combined zoeae in the single kreisel are then divided among the two double kreisels and the C. perlatus are all placed in the single kreisel so I can better track their progress.
Across the board, this proves to be too large of a population to sustain and I see massive die-offs on or around 10-14-20. At this point, it is also unclear how many of which species remain because they have all become intertwined.
10-15-20 I begin moving megalopa over to the transition tank, where all species reside together, eventually relocating 632 mixed-species megalopa to the transition tank.
10-25-20 The first megalopa takes a shell and walks onto land (assumed to be clypeatus as they are oldest). Over the next 25 days, 131 megalopa (mixed clypeatus, perlatus, and compressus) take shells and are moved to the temporary land tank.
10-31-20: Big Red (C. perlatus) spawns for the second time, on her own, in the saltwater pool. Roughly 3/4 of the spawn is siphoned out and added to the single kreisel where I can track them more carefully this time. The rest remain in the saltwater pool within the tank, but these do not appear to survive more than a day or two at most.
11-19-20: First C. perlatus megalopa from the second spawn is moved to the transition tank, where 5 or 6 remaining stragglers from the earlier batch are still taking shells or staying in the water in shells.
12-30-20: Final stats for 2020, there are: 125 C. clypeatus survivors; only 3 C. compressus survivors; and 0 C. perlatus survivors.
5-31-21: Hermit House officially moves from Lockport, New York to Blacksburg, Virginia. It’s a difficult move for the crabs and seems to delay C. clypeatus breeding by more than a month. The C. lila, C. perlatus, and C. compressus breeding individuals appear adversely affected by the move. As a result, there are no exotic spawns in 2021. All spawns in 2021 are from C. clypeatus.
9-28-21: Spawning begins. The first spawn is from one of the 2018 captive bred babies, now three years old. The saltwater pool is a 2.5 gallon, filtered tank, with live rock, copepods, amphipods, seagrass, and snails (for the first time not just a small pool with a bubbler). The crabs seem to like it and spawn nine more times over the next three months. It’s more than I can handle but I attempt to keep at least some from every spawn.
10-16-21: First megalopa begin to appear (on day 19, which is later than usual). Over the next nine days, 372 megalopa are moved to a makeshift transition tank. Lack of sufficient nannochloropsis (pandemic shipping delays and supply chain issues) and lack of natural light (in my new garage setup) are decidedly likely factors in the late transition.
10-24-21: The first megalopa begin to take shells and move onto land. Over the next week, 158 megalopa in shells are moved to the land tank.
11-13-21: 138 survivors are moved to the 20-gallon tall tank.
11-15-21: Survival rates are very low (for the second batch of spawns) and none are making megalopa. I have ~500 zoeae from the mid-October spawns and ~400 from the late October spawns remaining. Nannochloropsis finally arrives and is added to the tank.
11-16-21: The next batch of zoeae (all spawned in mid-to-late October) begin to transition to megalopa. This takes almost 21 days. Transition finally begins the day after fresh nannochloropsis arrives and the water is liberally dosed with it. I begin to suspect that the lipids in nanno are an essential element in surviving that difficult molt from Stage 5 to megalopa. Over the next twelve days, 451 megalopa are moved to the transition tank.
11-26-21: Temperatures and lighting in the garage make conditions less than ideal for megalopa and they incur heavy losses. I relocate the transition tank inside my house, move 138 survivors over, and cross my fingers.
12-2-21: The first megalopa (from the October spawns) take a shell and walk onto land. Over the next eleven days, 48 are moved to the land tank.
12-12-21: I begin to move the survivors over to the 20-gallon land tank and discover that phorid flies (adults and larvae) have found their way into the tank and have been killing the newest babies. Of the 48 survivors, only 29 remain.
12-31-21: A difficult and very frustrating breeding year ends without an accurate account of survivors (and only C. clypeatus, no exotics), but I expect it to be somewhere in the range of 100. A full count (and subsequent update) will take place in 2022.
9-6-22: (Day 1) First (a surprise) spawn of C. perlatus. Approximately 1,500 zoeae are placed into the new, larger kreisel build. Conditions kept at 33PPT salinity and 81 F temperature.
9-10-22: (Day 5) First sheds begin, about 20% shed ultimately shed on day five. They do not appear to eat live artemia, but are eating a number of powdered foods for corals and fish fry.
9-10-22: (Day 6) Approximately 60% shed on day six. Lots of partial water changes. A rough population count yields 1,100 survivors (~50 lost).
9-11-22: (Day 7) Final 20% shed into larval stage two. Good coloration developing. Some 10% remain small/colorless.
9-13-22: (Day 8) Still not eating live artemia. A day filled with doubts.
9-14-22: (Day 9) Saw a very few sheds, perhaps the start of larval stage three, or stragglers making stage two (more likely). Salinity ran high overnight (35-36 PPT), gradually adjusted readings back down to 33 PPT.
9-15-22: (Day 10) Approximately 50% shed today, visibly larger, definitely moving into stage three.
9-16-22: (Day 11) Lots more sheds. Did a full clean to remove brown algae that had overtaken all surfaces of the kreisel.
9-18-22: (Day 13) 795 C. perlatus survivors in various larval stages. Still no sign they are eating artemia. Spent many hours removing larger stage artemia as they also consume food and defecate, fouling the water faster than zoeae alone.
9-19-22: (Day 14) Shed day, moving into larval stage four. 225 sheds removed.
9-20-22 (Day 15) Removed 265 C. perlatus sheds today.
9-21-22: (Day 16 and Day 4): Received an overnight shipment of C. lila zoeae from Darcy Madsen. Nearly all survived transit. Experimentally added a few day-four C. lila zoeae to the C. perlatus stage-four zoeae. No obvious issues, no aggression observed. C. lila are very slow and docile. Extremely small eyes (tiny black pinpoints) compared to larger-eyed C. perlatus and C. clypeatus. C. lila are still highly light-reactive, though, despite having small eyes, also very pale of color and sluggish as zoeae … until touched, then C. lila exhibit spastic jerking movements (escape response?).
9-22-22: (Day 17 perlatus; Day 5 lila; Day 1 clypeatus). Moved 755 surviving C. perlatus to the original 10-gallon kreisel. Moved lilas to the new large kreisel (hereafter referred to as Big K), and set up the old double kreisel for the PPs.
9-24-22 (Day 19 perlatus; Day 7 lila; Day 3 clypeatus). First morning observation reveals that C. lila have all made megalopa overnight after only a week in the water. 704 moved to a hastily assembled transition tank that is 12″ deep (no exit provided, initially). C. lila megalopa are ravenous and eat in a feeding frenzy. Two C. perlatus megalopa are found in the ten-gallon kreisel, both deceased, 552 still surviving as zoeae. 7,400 C. clypeatus stage one zoeae are moved to the recently emptied Big K. Meredith Hass takes ~7,000 C. clypeatus zoeae to attempt to raise.
9-25-22: (Day 20 perlatus; Day 8 lila; Day 4 & 1 clypeatus). 64 C. perlatus megalopa get moved temporarily to a half-full side of the double kreisel. Huge new spawn of C. clypeatus in the 2.5 gallon saltwater pool inside the 120-gallon tank. C. lila continue to eat various sinking pellet foods voraciously.
9-26-22: (Day 21 perlatus; Day 9 lila; Day 5 & 2 clypeatus). Completed transition tank for C. perlatus megalopa and moved 87 over. 552 C. perlatus are still zoeae.
9-27-22: (Day 22 perlatus; Day 10 lila; Day 6 & 3 clypeatus). 57 C. perlatus megalopa are moved to transition tank. Unclear what they are eating. Plan to remove them and target feed (they will eat in a small container with a bright light shining on them). Shipped 3,000 C. clypeatus zoeae each to Heather Baumer and Jaimie Heard for their individual breeding attempts. ~750 zoeae in each fish bag with 2 cups saltwater (37 PPT salinity to help with buoyancy) and 12% nannochloropsis added was sufficient to assure survival during transit.
9-28-22: (Day 23 perlatus; Day 11 lila; Day 7 & 4 clypeatus). 20 more C. perlatus megalopa are moved to the transition tank. C. clypeatus are (thankfully) eating live artemia now.
9-29-22: 30 more C. perlatus megalopa moved to transition tank.
9-30-22: (Day 25 perlatus; Day 13 lila; Day 9 & 6 clypeatus). 17 C. perlatus megalopa moved to the transition tank. C. lila megalopa (previously swimming) suddenly vanished. Hopefully moved into shells.
10-1-22: (Day 26 perlatus; Day 14 lila; Day 10 & 7 clypeatus). (Adult C. clypeatus mating behavior observed, second round of the season.) Used a large siphon to remove the shells in the C. lila transition tank and found more than 100 survivors both in shells and unshelled. Fed them and returned to the transition tank. Will do this every morning going forward.
10-10-22: (Day 35 perlatus; Day 23 lila; Day 19 & 16 clypeatus). First C. perlatus observed wearing a shell (in the water). 3 C. lila moved to land (they appear to spend a LONG time in the water, in shells, before coming onto land). Only 750 C. clypeatus zoeae remain, despite best efforts to keep them alive. Very discouraging.
10-14-22: (Day 39 perlatus; Day 27 lila; Day 23, 20, & 1 clypeatus). New C. clypeatus spawn this morning. Will be shipping most of these to other potential breeders. Exhaustion has overtaken all personal efforts.
10-17-22: Shipped ~3,000 four-day-old C. clypeatus to Meredith Hass by UPS overnight. (2 c saltwater each bag, 37-38 PPT to help with buoyancy, and 60ml of nannochloropsis for oxygen and food. All survived transit.)
10-18-22: (Day 43 perlatus; Day 31 lila; Day 27, 24, & 5 clypeatus). 53 C. lila have been moved to land in shells. 15 C. perlatus megalopa are moved into the C. lila transition tank as it was becoming too much to keep two, active transition tanks cleaned and fed.
10-20-22: City-wide power outage today. Hermit House’s new emergency generator saved the day. No losses.
10-24-22: Approximately 3,000 C. clypeatus zoeae are shipped by overnight UPS to Jaimie Heard for her third (fourth?) breeding attempt this year.
10-25-22: Approximately 3,000 C. clypeatus zoeae are shipped by overnight UPS to Michelle Kuhn for her first breeding attempt.
10-31-22: (Day 56 perlatus; Day 44 lila). Broke down straw transition tank to find three dead that had made the final transition to land hermit and drowned. Found two still living megalopa and placed them in the saltwater pool in the lila tank. One immediately took a shell and walked out, the other is believed to have done the same later. Final count would make it 76 C. lila captive-bred babies and 3 C. perlatus captive-bred babies.
11-4-22: (Day 60 C. perlatus; Day 48 C. lila). Moved all babies from the large kritter keeper land tank to the 20-tall nursery tank. Moved 79 over, which (if I counted correctly when I moved them to land the first time), means there have been zero losses. However, for the first time since 2018, there are no C. clypeatus survivors out of all the spawns and all the attempts. None by me, and none by any of the other breeders who tried this year.
- C. lila do not appear to catch and eat live artemia and may even eat very little before making megalopa on day seven (after two larval stages), but nannochloropsis during the zoeal stages seems to be beneficial. They eat ravenously as megalopa and spend an extended amount of time in the transition tank as shell-wearing megalopa (15-20 days). C. lila thrive in a deep-water transition tank with tall driftwood for climbing out and above the waterline.
- C. perlatus also do not appear to eat live artemia as zoeae (not at any stage). C. perlatus do benefit from direct feeding, though–both as zoeae (in 4 larval stages) and after making megalopa (on or after day 19). They did not seem to benefit from deeper water in the transition tank the way C. lila did, but it did not appear to hurt them, either. They did not climb out on their own–not with a ramp, nor with the driftwood. They stayed in the water, eating and growing, but without taking shells for more than a month as megalopa. After successfully forcing the last few survivors to leave the water (as a last, desperate effort), I have concluded that captive-bred C. perlatus will benefit from/appear to require external pressure/environmental stress to encourage them to take shells and leave the water. If I had figured this out sooner, I would have had around a dozen survivors from that original 1,500 instead of three.
- Something is definitely missing for C. clypeatus in my new setup. The past two years (in Virginia, in my garage) have been a real struggle and there were no survivors at all this year. The only variable I can think that has completely changed is that of natural sunlight. In my Lockport setup, the kreisel sat directly in front of a window and received lots of bright, natural sunlight from the back side during daylight hours. In my new setup, the light has been very bright, but all overhead, and all artificial lighting. In 2023, I will try the kreisel in a location that receives bright, natural sunlight for C. clypeatus.
The adoption form for any of my captive-bred babies can be found here.If you would like to donate funds to help further the cause of sustainable, ethical, hermit crab husbandry, you can do so here: Thank you!