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A mating situation with only one male and one female is fairly straight forward... and in the case of a breeding loan the 50/50 in which the male's owner and the female's owner each get 50% of the offspring is the norm in the hobby world.
Where things can get complicated is if one female is mated to multiple males while she is in the same instar. Females definitely take multiple partners in the wild ( http://cat.inist.fr/?aModele=afficheN&cpsidt=2720288 ) and this practice, when observed in captivity is believed to lead to more successful eggsacs. the reason this is so has to do with some specifics in tarantula reproductive biolgy. i will begin with a lesson in tarantula and general spider biology. first, please read http://www.thebts.co.uk/old_articles/natural.htm to brush up on the reproductive process of our friend the tarantula. theraphosid use what is refered to as defered reproduction. humans and probably most other mammals are nondeferred... when a woman is inseminated by a healthy mature male the sperm must merge with the egg in a matter of days or they will die. a human female can not defer the introduction of sperm to egg. tarantulas on the other hand do not introduce the sperm onto the eggs until they are actually laying the eggs and making the eggsac... further, female spiders who mate with multiple partners tend to produce more and larger eggsacs.
Now, since the terms of a normal 50/50 loan no longer apply, i submit that a single share system be used. A person gets a single share per spider they introduce into a breeding equation. e.g. If Adam breeds his male to his female and then later borrows a male from Beth then Adam has two shares and Beth has one share of any offspring produced subsequent to introduction of Beth's male to the female. If an eggsac with exactly 99 viable babies was produced after Beth's male was introduced to Adams female then Beth should get 33 babies and Adam should get 66 babies.
In the case of cohabitation it must be assumed that mating has taken place as once there are multiple male partners involved there will be no proof short of DNA analysis of parentage or actual status of insemination.
A CRITICAL POINT IN MULTIPLE MALE BREEDING SITUATIONS:
All owners should be made aware that a multiple male breeding situation is in the offering. All owners should agree to a system of dividing the spoils BEFORE any mating takes place. What should happen if the owner of a female enters into a 50/50 with the owner of a male, without telling the owner of the male that the female has already been mated during her current instar? I don't know right now, but that is a situation that has the potential to get ugly... *especially* if the owner of the female denies the owner of the male right to ANY of the offspring subsequently produced!
This thread is intended to discuss the finer points of nondyadic (not two partners) breeding loans.
http://www.thebts.co.uk/old_articles/natural.htm
http://cat.inist.fr/?aModele=afficheN&cpsidt=2720288
http://www.eeza.csic.es/eeza/documentos/articulo.pdf
Where things can get complicated is if one female is mated to multiple males while she is in the same instar. Females definitely take multiple partners in the wild ( http://cat.inist.fr/?aModele=afficheN&cpsidt=2720288 ) and this practice, when observed in captivity is believed to lead to more successful eggsacs. the reason this is so has to do with some specifics in tarantula reproductive biolgy. i will begin with a lesson in tarantula and general spider biology. first, please read http://www.thebts.co.uk/old_articles/natural.htm to brush up on the reproductive process of our friend the tarantula. theraphosid use what is refered to as defered reproduction. humans and probably most other mammals are nondeferred... when a woman is inseminated by a healthy mature male the sperm must merge with the egg in a matter of days or they will die. a human female can not defer the introduction of sperm to egg. tarantulas on the other hand do not introduce the sperm onto the eggs until they are actually laying the eggs and making the eggsac... further, female spiders who mate with multiple partners tend to produce more and larger eggsacs.
Now, since the terms of a normal 50/50 loan no longer apply, i submit that a single share system be used. A person gets a single share per spider they introduce into a breeding equation. e.g. If Adam breeds his male to his female and then later borrows a male from Beth then Adam has two shares and Beth has one share of any offspring produced subsequent to introduction of Beth's male to the female. If an eggsac with exactly 99 viable babies was produced after Beth's male was introduced to Adams female then Beth should get 33 babies and Adam should get 66 babies.
In the case of cohabitation it must be assumed that mating has taken place as once there are multiple male partners involved there will be no proof short of DNA analysis of parentage or actual status of insemination.
A CRITICAL POINT IN MULTIPLE MALE BREEDING SITUATIONS:
All owners should be made aware that a multiple male breeding situation is in the offering. All owners should agree to a system of dividing the spoils BEFORE any mating takes place. What should happen if the owner of a female enters into a 50/50 with the owner of a male, without telling the owner of the male that the female has already been mated during her current instar? I don't know right now, but that is a situation that has the potential to get ugly... *especially* if the owner of the female denies the owner of the male right to ANY of the offspring subsequently produced!
This thread is intended to discuss the finer points of nondyadic (not two partners) breeding loans.
Hi Chris,
Thanks for your input. And many congrats on yours and John's success with the C.crawshayi, this was the first successful attempt to breed these in the US, no?
I ask because if I introduce more then one or two different males to the female my chances of a sac are increased twofold at least.
Cheers,
Steve
Ive had them pair several times over a 1 month period in the tank they were kept in,since sperm is stored and released with the eggs into the sac the more the better,ive noticed higher yields on multiple mating produced sacs. let him enjoy it while he can.lol
Quote:
Much appreciated, Paul!Originally posted by Rookie
Hey Joy,
I'm almost afraid to ask, but did the male survive the mating process? I usually try to save most G.Pulchra pics that I come across so I can say to my friends "Few years from now, and there's Peso". But I honestly have to say those might be the nicest Pulchras I've seen so far in my hunt. Their coloration is awesome; almost jet black. They look great. They're also very appropriate for Halloween
Yes, he survived, though he wouldn't have if the female had had her way! I just caught him making a new sperm web today, so will put him back in with #1 female (the one in the picture is #2) once I've fed her up a bit.
Holley, it will be interesting to see if your male reacts differently to my females. It's amazing how differently they can respond to different (but seemingly identical) partners. The presence of Susan's male, too, may be a stimulant. I personally have had a much higher mating success rate with multiple males--100% except for the time I tried it with C. crawshayi. THAT was a circus!
Praying for fertility,
Paul
Joy
http://www.thebts.co.uk/old_articles/natural.htm
Most species possess a pair of spermathecae although in some species these have fused to form a single pocket. After a varying period of time the female constructs a thick silken mat upon which the eggs are deposited (between 20 and 1000 in total). The eggs are fertilised as they pass the openings to the spermathecae. Once finished, she will either cover the eggs with further silk layers suspending the egg sac within her retreat (many African species) or manipulate it into a spherical egg sac which she can grasp with her fangs (new world species, Hysterocrates spp. and most Asiatic species). The transportable egg sac species are able to move their egg sacs towards optimal heat and humidity conditions. Under captive conditions some Avicularia spp. have been seen to expose their egg sacs to the warmth of fluorescent tubes. It is likely that tarantulas expose their egg sacs to the warming early morning sun as some other mygalomorph species do (e.g. Macrothele calpeiana). The majority of tarantulas produce one egg sac between moults. There are species like Psalmopoeus cambridgei and Tapinauchenius purpureus which are capable of producing two egg sacs between moults (Pterinochilus murinus has even been known to produce three). Where multiple egg sacs are produced they are always produced consecutively following the dispersal of the spiderlings from the previous sac. Some captive, unmated females (Psalmopoeus cambridgei, P. reduncus and Tapinauchenius plumipes) have also been reported laying infertile egg sacs.
http://cat.inist.fr/?aModele=afficheN&cpsidt=2720288
Despite their general notoriety and popularity as pets, little is known of the behavioural ecology of'tarantulas' or theraphosid spiders. We studied a theraphosid of the Arizona deserts, Aphonopelma sp., to determine behavioural events crucial to successful courtship and mating. Males search for spatially scattered females and, at short range, may detect females by
substrate-borne cues. When two males are present with a single female, no direct competition such as aggression is observed. Both males may mate with a single female in rapid succession, with no evidence of post-copulatory mate guarding. Despite the potential for sexual cannibalism, courtship and mating behaviour patterns exhibit few aggressive elements and males nearly always survive sexual encounters with females. The mating system of this Aphonopelma species may best be described as a type of scramble-
competition polygyny, in which the ability of males to locate receptive females is an important determinant of mating success in males. Multiple mating by females renders predictions concerning fertilization success uncertain, due to the possibility of sperm competition and 'cryptic' female mate choice.
http://www.eeza.csic.es/eeza/documentos/articulo.pdf