Culling Offspring

A much overlooked and underused practice

The voluntary culling of offspring is a practice all too few people participate in. In reality this is a disservice to the hobby as a whole on several levels, and has amounted to a disturbing trend.

In today's world of information, knowledge, and availability of animals, the number of people breeding reptiles increases every year.
All these things are indeed assets to the hobby, but the relative ease of reproducing many species has resulted in virtually every person in possesion of a pair of leopard geckos or cornsnakes to feel they have to breed them.
The problem lies in the fact that this results in nothing more than more animals being produced without rhyme or reason and very little progress being made.
In part, the reason behind this lies in the desire for monetary gain. If an egg hatches, the baby will be sold regardless of whatever characteristics that baby might or might not bear. This includes behavioral traits as well.
The simple truth is this is irresponsible and not every hatchling produced needs to be added to the gene pool.

What we have today is a multitude of small time breeders with one pair of this and one pair of that just hatching eggs for the sake of producing more animals and selling everything produced with no regard for the betterment of the captive lineages. This often results in the sale of sibling pairs, which promotes inbreeding for no purpose, and the sale of mediocre animals which will go on to produce more mediocre animals and so on.
The entire attitude of breeding for the sake of producing more animals to sell needs to be corrected.

I have seen estimates that in excess of 150,000 leopard geckos were produced this year(2002). My point is why should you or I put together a group of leos for breeding? What purpose would it serve? None whatsoever beyond the generation of a small amount of additional income.
The current effort put into the reproduction of many common species must be shifted to the area of refinement, and this is dependant on culling.

So what is culling anyway? Contrary to the belief of some, culling is not keeping the best one or two offspring for your group and selling the rest. Many large scale professional breeders refer to this as culling, but it is just a facet of selective breeding, since they would have just sold them all if none met their personal standards to merit keeping.
Culling is the destruction of any offspring bearing any undesirable, or less desirable traits. By traits, I do not mean only color and pattern.

I realize that the intentional killing of certain offspring is distasteful to some, and will be considered cruel by many. I am not writing this however to cater to the warm and fuzzy opinions of many today who claim the title of "herper" just because they keep a few reptilian pets.
Many people hold an inherent sympathy for the weak, or just the lives of the less desireable. There is little room for this shortsighted approach.
Nature itself is harsh and unforgiving in its methods and in what individuals are allowed to reproduce. We too must become strict in our standards, but we have to use different criteria.

That brings us to the question of how will the culling of offspring be accomplished? The answer will vary depending on the species involved. The degree of culling must be based on the relative abundance of a species as captive born. The more common a species, the more strict the criteria should be. Species which remain rarely bred may be limited to the culling of only deformed or otherwise defective offspring, while the most common species should be culled using much broader standards.

First and foremost, any offspring with physical deformities should be culled. Snakes born with one eye, or a spinal kink etc should not be sold. Likewise, lizards born with turned feet or deformed limbs should never leave your possesion.
Even though in many cases these conditions are not genetic, there is simply no reason to add less than perfect specimens to an already saturated market. It is all the more applicable if the condition is genetic, or suspected to be so. These animals should never be allowed to reproduce.
The only time that this standard could be relaxed would be when it concerns a species which is very limited in availability, and the specimen only has a minor nongenetic blemish but is still capable of needed reproduction.
Note I said species, not morph. Just because a morph is rare (and thereby commanding the coveted higher price tag), is no excuse to sell deformed specimens. Case in point, one eyed albino boas. There exists the possibility that this condition is a genetic defect resulting from inbreeding. When these snakes were still bringing several thousand dollars, a grand or two was deducted from the price of the one eyed individuals and they were sold regardless. This was greed, no more, no less.

A very important part of a breeding project that is often overlooked is to have a plan. Before you start to breed a species you need a goal, a result you are aiming for, a set of standards you want to meet.
The process begins of course with the careful selection of your founding stock. Do not be in a hurry to get your group together. Know what you are looking for and do not let the price figure in too heavily. Never settle for lower quality in order to save money. The founding stock is the basis of the entire project, and if you cut corners at the beginning, you are crippling your own efforts. Do not buy siblings with the intention of breeding them to each other. There is nothing wrong with buying siblings, but also buy another pair form a seperate bloodline and cross the pairs.

Now the main issue, you've hatched eggs, what do you cull? This is where it gets subjective. With all the possible breeding programs, there is no one answer. Alot will depend on the goals you established earlier.
Generally speaking, any offspring which are not at least as high quality as the parents are subject to culling. There is no reason to step backward. Anything involving the color or pattern traits will largely depend on the tastes of the breeder and his level of dedication to the perfection of the blood line.

Other characteristics however, should be held to stricter standards. For instance if you are breeding mountain kingsnakes or gray bands you will have some problem feeders. If, after a reasonable amount of time, you have some specimens that refuse to eat mice devoid of any manipulation, they should be culled. Nonfeeders should not be sold in the first place, even at discounted prices, and those that remain so should be removed from the gene pool. This will strengthen the captive lineages.

Likewise, if a specimen just fails to thrive it should be culled. I spent several years keeping and breeding bearded dragons. One fact of breeding this and other species which produce fairly large numbers of offspring is that a small percentage of them just will not take off. Some people, out of a sense of sympathy, or obligation, will put great effort into nursing these individuals, coaxing them to eat etc. I allowed several dragons to die naturally from their refusal to hunt for themselves, it needs to be done. My wife took one dragon many years ago and hand fed it, spending an hour or so per day for 4 weeks convincing it to eat. While this is a noble act, these animals should be culled. The weak have no place in the gene pool, and saving such animals is not doing the species, or future keepers any favors. The dragon my wife spent so much time with grew into a healthy adult, but we kept her until her natural death nine years later, and she was never bred.

These are merely some examples meant to make you think about where you are going with your breeding projects. Producing an animal for no reason other than to have a few more babies to sell is no longer acceptable in this time of over saturation of many species.
Where many common species are concerned, there exists no reason for experienced hobbyists to produce them at all. Their efforts are much better spent working with other species that are in need of being produced.

Things like leopard geckos and cornsnakes, including the common morphs, are already produced by the tens of thousands. These species are ideal for the kids, and the less experienced to get their first taste of breeding, and this is great. However, if you are an experienced hobbyist producing yet more leopard geckos, you are accomplishing nothing outside of your own self serving interests. At least a portion of every breeders efforts should be aimed at the advancement of the hobby as a whole.

I myself have been guilty to a degree of several points I have mentioned here. I'm not trying to convince you to stop producing common species. I am only saying that with many species the numbers being produced are more than adequate. More focus should be placed on quality rather than the quantity of the common species, and alot of the effort put into pumping out even more of these would be of better service to the hobby if applied to less common species, especially those that are not bred due to the lack of potential for financial reward.
In the past I have worked toward producing abberantly patterned California kings. This project was just for the enjoyment of seeing the odd patterns. In the process though, I also produced many average, or even below average looking hatchlings. I sold them all, often wholesale, just to move them. This practice benefitted nothing, and many of those should have really been culled. The availability of average looking cal kings does not warrant my producing even more. It does nothing for the refinement of the species, nor is there a need for more of these in the pet trade.

The majority of people will refuse to take culling to that level. They would equate culling a healthy but imperfectly banded cal king to lighting a cigarette with a $20 bill. These people will ensure the over abundance of the most common species, and their status as disposable pets. They also make it easier for those of us less concerned with money, and more so with the betterment of these species and the hobby as a whole to practice more strict culling.
At the very least, poor feeders, and weak or deformed hatchlings should be destroyed. There is really no valid excuse for selling them and their culling will only improve the gene pool.
Culling is not easy, and I do not enjoy it any more than you. As responsible breeders though, we must practice it to some degree.