Sea Hares mating and eggs

dkegflorida · Oct 28, 2022

I must have had some sea hare eggs on some plants for my tank because I never bought any and one day I noticed 2 sea hares in my tank. That was about 6 weeks ago and now they are mating and laying eggs everywhere! I egg survived and is the size of the older ones already. I have been scraping the eggs off and discarding as I don't want anymore of them.

ISpeakForTheSeas · Oct 28, 2022

dkegflorida said:
I must have had some sea hare eggs on some plants for my tank because I never bought any and one day I noticed 2 sea hares in my tank. That was about 6 weeks ago and now they are mating and laying eggs everywhere! I egg survived and is the size of the older ones already. I have been scraping the eggs off and discarding as I don't want anymore of them.

Nice video!

I'm not an expert, but I believe these sea hares may be Bursatella leachii - if so, these actually become capable of reproduction after 2-3 months, then die shortly after mating. I'm not sure how long they last after mating, but I can't imagine them lasting too terribly long (based on their short lifespans and on the similar behaviors of many cephalopods, I'd guess probably a week or two at the most). How many egg casings have you had in your tank?

Also, for clarification here, you had one of the eggs hatch, develop, and settle into a new sea hare (now nearly the same size as the two adults) in your tank, yes?

TokenReefer · Oct 28, 2022

Pretty awesome looking. Makes my boring ol cuc look like a k car lol

vetteguy53081 · Oct 28, 2022

Nice- its amazing as to what their masses look like. Some look like silly string

dkegflorida · Oct 28, 2022

ISpeakForTheSeas said:
Nice video!

I'm not an expert, but I believe these sea hares may be Bursatella leachii - if so, these actually become capable of reproduction after 2-3 months, then die shortly after mating. I'm not sure how long they last after mating, but I can't imagine them lasting too terribly long (based on their short lifespans and on the similar behaviors of many cephalopods, I'd guess probably a week or two at the most). How many egg casings have you had in your tank?

Also, for clarification here, you had one of the eggs hatch, develop, and settle into a new sea hare (now nearly the same size as the two adults) in your tank, yes?

They first two started laying eggs about 4 weeks ago. And yes, on Oct 8 I saw a sea hare only 1" long and now it is the size of the parents and all 3 are laying eggs now.

dkegflorida · Oct 28, 2022

I took one from the main tank and put inside my indoor tank to clean up some algae. It already had eggs and deposited them 2 days after being in the tank :-(

ISpeakForTheSeas · Oct 28, 2022

dkegflorida said:
They first two started laying eggs about 4 weeks ago. And yes, on Oct 8 I saw a sea hare only 1" long and now it is the size of the parents and all 3 are laying eggs now.

Interesting. Now I’m curious how long the mating process goes, and how long it will take for the mating pair to die.

Anyway, if it is Bursatella leachii, the article I’ve found on rearing them says the eggs take ~8-9 days to hatch, and the larvae go through ~30-35 days as planktonic larvae before settling. So, I don’t know how long it takes for these guys to reach 1” in size, but if ~4 weeks is accurate, you most likely had that third one in your tank prior to the other two mating.

I honestly wouldn’t expect any survivors from the eggs in a normal tank, especially if you’re not dosing phyto regularly, so I wouldn’t worry too much about having a sea hare population explosion in your tank.

dkegflorida · Oct 28, 2022

ISpeakForTheSeas said:
Interesting. Now I’m curious how long the mating process goes, and how long it will take for the mating pair to die.

Anyway, if it is Bursatella leachii, the article I’ve found on rearing them says the eggs take ~8-9 days to hatch, and the larvae go through ~30-35 days as planktonic larvae before settling. So, I don’t know how long it takes for these guys to reach 1” in size, but if ~4 weeks is accurate, you most likely had that third one in your tank prior to the other two mating.

I honestly wouldn’t expect any survivors from the eggs in a normal tank, especially if you’re not dosing phyto regularly, so I wouldn’t worry too much about having a sea hare population explosion in your tank.

Thanks for the info. I will see what happens...

dkegflorida · Oct 29, 2022

I'm curious how long they have eggs inside them. Attached is a video of my sea hare today (that I moved to my inside aquarium 5 days ago) and its laying eggs for second time.

OldRed1 · Oct 29, 2022

dkegflorida said:
I must have had some sea hare eggs on some plants for my tank because I never bought any and one day I noticed 2 sea hares in my tank. That was about 6 weeks ago and now they are mating and laying eggs everywhere! I egg survived and is the size of the older ones already. I have been scraping the eggs off and discarding as I don't want anymore of them.

Dumb question, but how do I get the video to load?

Tcook · Oct 29, 2022

What does your main "tiled" tank look like?

dkegflorida · Oct 29, 2022

OldRed1 said:
Dumb question, but how do I get the video to load?

The videos were working yesterday. Today I can't view any videos on R2R on my phone. But works fine on my computer.

dkegflorida · Oct 29, 2022

Here are the videos again if you cannot load/view the previous ones.

marine

36 new items · Album by Douglas Kegler

photos.app.goo.gl

dkegflorida · Oct 29, 2022

Tcook said:
What does your main "tiled" tank look like?

dkegflorida · Oct 29, 2022

I uploaded pics to this folder.

marine

36 new items · Album by Douglas Kegler

photos.app.goo.gl

Tcook · Oct 29, 2022

dkegflorida said:
I uploaded pics to this folder.

marine

36 new items · Album by Douglas Kegler

photos.app.goo.gl

Wow. So those were real scuba sounds in your hare video!

dkegflorida · Oct 31, 2022

Yes. I have a diving ventilator I use. I uploaded a video of me scrubbing the bottom.

New video · Saturday, Oct 22, 2022 🎬

Tap to view!

photos.app.goo.gl

dkegflorida · Nov 12, 2022

ISpeakForTheSeas said:
Interesting. Now I’m curious how long the mating process goes, and how long it will take for the mating pair to die.

Anyway, if it is Bursatella leachii, the article I’ve found on rearing them says the eggs take ~8-9 days to hatch, and the larvae go through ~30-35 days as planktonic larvae before settling. So, I don’t know how long it takes for these guys to reach 1” in size, but if ~4 weeks is accurate, you most likely had that third one in your tank prior to the other two mating.

I honestly wouldn’t expect any survivors from the eggs in a normal tank, especially if you’re not dosing phyto regularly, so I wouldn’t worry too much about having a sea hare population explosion in your tank.

UPDATE - 8 weeks now since the first eggs were laid and the two are still moving along eating algae. As you suspected, I haven't seen any new ones but I haven't been diving inside the tank in 2 weeks.