Captive bred yashas goby dorsal fins?

Chrisv.

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Has anyone purchased the captive bred yashas? The ones at my LFS and many I have seen offered on LA do not have long dorsal fins. At first I thought it was a maturity issue, but this past weekend I saw some really big cb yashas at my LFS-- with short dorsal.

Any ideas? Are the missing dorsal fins a casualty of group rearing, where conspecific aggression is the issue? Do these eventually grow back?

In general, how have these cb yasha gobies done for people?
 

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Has anyone purchased the captive bred yashas? The ones at my LFS and many I have seen offered on LA do not have long dorsal fins. At first I thought it was a maturity issue, but this past weekend I saw some really big cb yashas at my LFS-- with short dorsal.

Any ideas? Are the missing dorsal fins a casualty of group rearing, where conspecific aggression is the issue? Do these eventually grow back?

In general, how have these cb yasha gobies done for people?
To me the dorsal fin depicts males from females - This is also from me already knowing in many other fish long fins = Male, short fins = Female.
My yasha (No clue if it’s wild or not, I have had it for about 18 months though) has a long dorsal and ones in my LFS have mixed but usually there’s always a pair and one has the long dorsal fin whereas the other has a short dorsal fin.
 
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Chrisv.

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To me the dorsal fin depicts males from females - This is also from me already knowing in many other fish long fins = Male, short fins = Female.
My yasha (No clue if it’s wild or not, I have had it for about 18 months though) has a long dorsal and ones in my LFS have mixed but usually there’s always a pair and one has the long dorsal fin whereas the other has a short dorsal fin.
Interesting. I did notice that many of the captive bred yasha gobies on LA were listed as female and they had short fins. My understanding is that the dimorphism between males and females is limited to the presence or absence of a black dot on the fused ventral fins. Females and juveniles lack the spot. I've not heard anything about dorsal fin dimorphism.

I have no idea if the US captive bred yasha gobies are distributed internationally.
 

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Interesting. I did notice that many of the captive bred yasha gobies on LA were listed as female and they had short fins. My understanding is that the dimorphism between males and females is limited to the presence or absence of a black dot on the fused ventral fins. Females and juveniles lack the spot. I've not heard anything about dorsal fin dimorphism.

I have no idea if the US captive bred yasha gobies are distributed internationally.
There is a pair of Yasha's on DD now. Both with long dorsals and one with the spot on the ventral fin. So I agree with you. Spot makes it male.
 
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Chrisv.

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To make things even more confusing, the RWU aquaculture dept (which produces the cb yasha gobies in the us) Facebook page had a picture of a whole ton of yasha offspring, with long dorsal fins.
Screenshot_20211012-192708.png
 
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Chrisv.

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It’s so confusing. Maybe I can try reaching out to the folks at RWU. Maybe some of them are on r2r!
 

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Has anyone purchased the captive bred yashas? The ones at my LFS and many I have seen offered on LA do not have long dorsal fins. At first I thought it was a maturity issue, but this past weekend I saw some really big cb yashas at my LFS-- with short dorsal.

Any ideas? Are the missing dorsal fins a casualty of group rearing, where conspecific aggression is the issue? Do these eventually grow back?

In general, how have these cb yasha gobies done for people?
I have owned yashi gobies for almost 10 years now. My most recent one I bought had very long fin. He paired with my candy cane pistol right away within minutes. They lived together for about 2 months then one morning I woke up and pistol moved from there shared home in the sand under a rock to the other side of my 120 gallon. I was upset but yashi was even more upset then me. For weeks he looked for pistol but could not find him. Over this time I noticed his dorsel fin getting smaller and smaller. At about 1 month later it was almost completely gone no fin at all. Yashi still not happy constantly looking for is pistol mate he everntually jumped into my overflow. Days went by before I noticed. I removed yashi from overflow and used a long clear pvc pipe to reintroduce yashi to pistols new burro under another rock 4 feet away from there original home. Luckily Yashi swam right into the new burro and I immediately hear pistol start to pop his claws so I know yashi found his friend. Now important part over the next 2-3 months yashi dorsel fin started to grow back and about 4 months later it is good and long like never happens. I wonder how much of him losing his fin had to do with stress?
 

Baldguy

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I'll give you another twist. I was talking to one of the best lfs in my area. He's been selling bonded pairs of these captive bred yasha's. He gets a bunch in and lets them pair up on their own. He's kept up with some he's sold and says the supposed male never developed the black spot. Strange.
 

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I would venture to say dorsal fins will grow back once in less stressful environment…..
 
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Chrisv.

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I have owned yashi gobies for almost 10 years now. My most recent one I bought had very long fin. He paired with my candy cane pistol right away within minutes. They lived together for about 2 months then one morning I woke up and pistol moved from there shared home in the sand under a rock to the other side of my 120 gallon. I was upset but yashi was even more upset then me. For weeks he looked for pistol but could not find him. Over this time I noticed his dorsel fin getting smaller and smaller. At about 1 month later it was almost completely gone no fin at all. Yashi still not happy constantly looking for is pistol mate he everntually jumped into my overflow. Days went by before I noticed. I removed yashi from overflow and used a long clear pvc pipe to reintroduce yashi to pistols new burro under another rock 4 feet away from there original home. Luckily Yashi swam right into the new burro and I immediately hear pistol start to pop his claws so I know yashi found his friend. Now important part over the next 2-3 months yashi dorsel fin started to grow back and about 4 months later it is good and long like never happens. I wonder how much of him losing his fin had to do with stress?
Wow! That’s very interesting! I had never thought of the relationship between the shrimp and the goby to obligatory on the part of the goby.
 
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Chrisv.

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Well I’ve made a nuisance of myself and emailed someone at RWU. I will report back what they tell me!
 

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I believe that's something with the breeding causing the short dorsal. Plus RWU will not release males at this time,
 
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Chrisv.

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I believe that's something with the breeding causing the short dorsal. Plus RWU will not release males at this time,
I suspected that they might be holding back males. The live aquaria postings have been 100% female.

any idea why they are only releasing females? It’s not like the average aquarium keeper is competition, and the competition would no doubt go for wild brood stock.
 

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Wow! That’s very interesting! I had never thought of the relationship between the shrimp and the goby to obligatory on the part of the goby.
Well I’m not exactly saying that In my case it seemed yashi was very dependent on the pistol I’m sure yashis that have never been paired up before would not know what they’re missing therefore might not care something else could be the stress factor
 
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Chrisv.

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Well I’m not exactly saying that In my case it seemed yashi was very dependent on the pistol I’m sure yashis that have never been paired up before would not know what they’re missing therefore might not care something else could be the stress factor
These captive bred ones have never had a shrimp though and their fins look so…sad! I will post back if the RWU folks email me back. Still curious as to why they only release females.
 

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These captive bred ones have never had a shrimp though and their fins look so…sad! I will post back if the RWU folks email me back. Still curious as to why they only release females.
There is probably a very smaller % of males that are born so to keep the breeding process going keep males to have higher chance of more babies. And they are sad because they need to be adopted :)
 
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