sorting crickets by size

[oldseahorse]

Living in costa rica, I rescued some red eyed leaf frogs as eggs from a place that would have certain death. Initially I fed them with captured fruit flies. I captured some house crickets and bred them, as there are no "feeders" for sale in central america. But I was inexperienced during the breeding, and now have crickets of all sizes mixed together .I would appreciate ideas on how to separate these bugs into sizes, as my frogs can are kinda like Goldilocks, they want them "just right" Thanks Mike in Paradise

[elly]

All I can suggest is removing the big ones by hand.

[DEW]

Hi Mike,

I just had the same problem. I had a bunch of very small (pinhead) with progressively larger babies. I could feed the larger to the baby grays but feeding the pinheads now would be a waste of a cricket. I finally tried something that worked well for me. I put all of the crickets that were in that group in small plastic containers. The first container I drilled a bunch of very tiny holes in it all around the bottom, just large enough for the pinheads and smaller to get out. I took those and put them in one cricket keeper to grow. The next container had slightly larger holes to let the next size out,I put them in another cricket keeper. Each container had progressively larger holes.
From now on I will not leave the egg trays in the breeding containers as long and there will be less discrepancy in size.

[oldseahorse]

O K great idea. I tried your suggestion and am having some success. My last generation is getting ready to breed, they are starting to get wings. Any idea how long they start laying eggs after the get their wings ? And ...... how long do you suggest I leave the egg medium in with them , before moving to the incubating container. Muchos Gracias
I am just starting out and don't know much.

[DEW]

Here is a great page on cricket breeding from Fluker's teacher aids, cricket biology. It goes into great detail about lifecycle and breeding.
A quick rundown of the basics are; When the last instar molts and develops wings, called emergence, the cricket is called a day one adult. Females and males become sexually active at 3-4 days post emergence. females do not lay eggs until fertilization takes place. Once she has begun to oviposit (lay eggs) at about 10 days of age if a successful mating has taken place and if all the right conditions are met the eggs will start to hatch at 13 days if incubated at 86 degrees F. so, as you can see there are a number of variables.
For the full text;
http://www.flukerfarms.com/PDFs/Cricket.pdf
Hopes this helps.

As for the sorting. I left my containers with the holes in a larger container overnight. Make sure the holes are tiny, just barely large enough to allow the size cricket you are wanting to separate to exit container, otherwise larger crickets can squeeze through. You also may wish to use a pretty thick plastic container for the holes otherwise larger crickets will make the holes larger quickly. Make sure to provide afood and a water source in both containers, you may wish to provide a food source that is a more attractive in the outer container than what is provided in the inner container. I used a mixture of chicken starter, fish food flakes, frog food, and nori ( seaweed sheets) the same thing used in sushi rolls. these provide a stronger smell than what I usually provide but I went a little further and provided only a piece of carrot and a piece of potato for the food and the water source in the inner container, just basic necessities. This will encourage the smaller crickets to investigate the smell.

Good luck,
Dani

Sorry, forgot the question about how long to let females have access to egg trays.I experimented with several methods and what I found was; If I left the container in for a week or longer I had a greater variation in size in that batch than if I allowed only three days ( those just finished hatching) and all are close in size.

I also used a "screen" on top of the medium so that that other crickets were not burrowing through the media and eating the eggs. I got a much higher hatch rate using the screen. The problem with the screen method was getting just the right size hole and making sure it is cut to the exact size of the container if placed inside and directly on top of the media (touching) otherwise the females had to struggle to ovaposit if above the media at all and if the screen was not exactly the right size to fit tightly in the container then the other crickets were able to get under the screen. As for right size, I tried several and was amazed at what the crickets could squeeze through or get around. The only thing I found was the metal mesh top of an 30 gallon tank! Not exactly economical but what I had here and I was getting frustrated. You could also secure a piece of the metal mesh (or whatever else you find that works)over the top of your container just make sure the media is all the way to the top so it touches the mesh. Using this method I had a far larger hatch rate than without any restriction to access to the eggs by other crickets. This allowed me to have fewer crickets in the breeding colony or just a really large number of hatchlings per container, an enormous advantage when feeding as many little frogs as I am

[oldseahorse]

Wow I put in a nickel and get out a dollar ! Thanks so much Dani . It looks like I will have a about a month between when my correct sized feeders will be too big and a new batch will be a quarter inch in size , and ready to feed. I'll have to go back to fruit flies. And.... the calcs for the "house cricket" in Flukers , may not be the same as my wild caught , now cultured central American black crickets. No pet store with rickets or THOUSANDS of mile. So much to learn. The saying in Spanish is "poco a poco" little by little. Las question for now..... how big are the holes in the screen that you used to prevent the adults from eating the eggs ? Mike in Costa Rica