Metabetaeus lohena larvae update
Posted: Wed Mar 21, 2012 2:56 pm
The short version is that I have kept one M. lohena larvae alive for the last 36 hours from 6am Tues to now about 6pm Wed.
Doing a take off of Paul Harvey now for the rest of the story.
Doing a little research it is believed that M. lohena larvae needs full salt water to develop. The advantage of plantonic larvae is that they can colonize new areas far afield by drifting on the currents and feeding on other planton. This would account for the limited yolk sac that Mustafa noticed in the previous pictures. This is opposed to H. rubra which produces a non feeding larvae with a large yolk sac that basically stays where it is released. I could provide the list of references upon request if you wish to read the scientific papers.
With a limited yolk sac in a larvae even for species with an abrieviated time as larvae feeding is a problem. I found an interesting article from this forum about breeding orange shrimp. This article discussed the modified french method for feeding the shrimp larvae. Basically you create a soup of algae to feed the larvae. No other food. Apparently algae is high in proteins. The larvae feeds off the algae and produces waste that feeds the algae. Without any other kinds of feeding you reduce your chances of crashes. The algae still needs the 16 hours of direct light.
Well problem number one. I crashed the algae. Nannochloropsis sp. I did not provide the algae with 16 hours of direct artificial light. I started another batch with good results but not before one female released her larvae. Now for problem number two. The next female dropped her clutch and I missed it. The third female's clutch I would not lose without a fight. I turned off the lights except for a pen light on the tank cover. My previous experience is that the larvae are strongly attracted to the light. I checked on the tank every hour from 8pm to 1am. Unfortunetly I fell asleep and woke up at 6am. The clutch was gone and no larvae to be found. Why didn't I use an alarm to wake myself? I was saved by daylight savings time. It was still fairly dark and after a thorough inspection I found two larvae. I caught one with my turkey baster and transfered it to the algae tank. The other larvae sank to the bottem and could not be found.
I was hoping for thirty maybe twenty or even ten but one is better than naught. I had the day off since I had to go to the dentist. About once a hour I checked on my larvae. By about noon or 6 hours in the algae soup the larvae was not floating but rested on the bottom of the tank. I was sure it was near death. Coming home from the dentist and after some chores I checked on the larvae again about 6pm. It was still alive. I checked again before bed, upon waking and coming home from work today and the larvae was alive and still on the tank bottom.
I am fully prepared for the larvae to be dead by bed time but obviously hope not. My algae soup has a sg of about 1.020+. Temps are room temps about 75 deg. f. 10000k light source inches from tank. Should the larvae die I will use the current protocol again. It seem logical until it fails after several attempts. No pictures available. Very difficult to see let alone film the larvae. Will provide update.
Ken P
Doing a take off of Paul Harvey now for the rest of the story.
Doing a little research it is believed that M. lohena larvae needs full salt water to develop. The advantage of plantonic larvae is that they can colonize new areas far afield by drifting on the currents and feeding on other planton. This would account for the limited yolk sac that Mustafa noticed in the previous pictures. This is opposed to H. rubra which produces a non feeding larvae with a large yolk sac that basically stays where it is released. I could provide the list of references upon request if you wish to read the scientific papers.
With a limited yolk sac in a larvae even for species with an abrieviated time as larvae feeding is a problem. I found an interesting article from this forum about breeding orange shrimp. This article discussed the modified french method for feeding the shrimp larvae. Basically you create a soup of algae to feed the larvae. No other food. Apparently algae is high in proteins. The larvae feeds off the algae and produces waste that feeds the algae. Without any other kinds of feeding you reduce your chances of crashes. The algae still needs the 16 hours of direct light.
Well problem number one. I crashed the algae. Nannochloropsis sp. I did not provide the algae with 16 hours of direct artificial light. I started another batch with good results but not before one female released her larvae. Now for problem number two. The next female dropped her clutch and I missed it. The third female's clutch I would not lose without a fight. I turned off the lights except for a pen light on the tank cover. My previous experience is that the larvae are strongly attracted to the light. I checked on the tank every hour from 8pm to 1am. Unfortunetly I fell asleep and woke up at 6am. The clutch was gone and no larvae to be found. Why didn't I use an alarm to wake myself? I was saved by daylight savings time. It was still fairly dark and after a thorough inspection I found two larvae. I caught one with my turkey baster and transfered it to the algae tank. The other larvae sank to the bottem and could not be found.
I was hoping for thirty maybe twenty or even ten but one is better than naught. I had the day off since I had to go to the dentist. About once a hour I checked on my larvae. By about noon or 6 hours in the algae soup the larvae was not floating but rested on the bottom of the tank. I was sure it was near death. Coming home from the dentist and after some chores I checked on the larvae again about 6pm. It was still alive. I checked again before bed, upon waking and coming home from work today and the larvae was alive and still on the tank bottom.
I am fully prepared for the larvae to be dead by bed time but obviously hope not. My algae soup has a sg of about 1.020+. Temps are room temps about 75 deg. f. 10000k light source inches from tank. Should the larvae die I will use the current protocol again. It seem logical until it fails after several attempts. No pictures available. Very difficult to see let alone film the larvae. Will provide update.
Ken P