Prose and Controversies: Culling

In the gecko breeding world, “culling” refers to “putting down” or killing  undesirable specimens.  All breeders recognize that some geckos hatch with undesirable traits.  The question is, when to eliminate these geckos and how to do it.

Who to Cull

There is little debate about putting down hatchlings that have severe deformities which will lead to a shortened, painful life.  These deformities include lack of eyelids in eublepharid geckos and abdominal hernias where the abdominal wall has not closed and cannot be repaired.  The real question comes when considering what to do about hatchlings that may have a reduced, but reasonable quality of  life or those whose genetic makeup could potentially weaken the gene pool of the species.

For example:

  • geckos with minor abnormalities that may require some special care such as notched eyelids (in eublepharid species) or foreshortened legs
  • geckos with cosmetic abnormalities that don’t require special care such as tail kinks, (congenitally) missing toes, bulgy eyes
  • geckos that appear not to gain weight or thrive compared to others of their age and species
  • geckos that have “muddied” genetics, such as leopard geckos that are het for more than one strain of albino
  • siblings of geckos that have “muddied” genetics or deformities

Those who favor culling some or all of the geckos that could have a reasonable quality of life as described above feel that the minor abnormalities observed may in fact be signs of more serious internal abnormalities that we can’t see.  These geckos, if bred, could significantly weaken the gene pool, especially for species where the captive population already has limited genetic diversity. Since there’s no way to guarantee that these geckos won’t be bred, it’s better for the gene pool if they are eliminated.  By the same token, some breeders would prefer to cull any gecko with “questionable” genetics and, by extension, all siblings as well, for the sake of the gene pool.  The feel that as long as they are selectively breeding, they have the responsibility to make appropriate selections to insure the strength and quality of the gene pool.

Gecko keepers who are opposed to culling point out that any animal that can have a decent quality of life deserves the chance to live.  They feel that most, if not all, species of geckos in captivity continue to be resilient and viable and that weak specimens will likely not breed well and will ultimately be eliminated from the gene pool through natural selection.

Obviously the culling issue mirrors the controversy of when human life begins as relates to the deliberate termination of pregnancy with all the accompanying political, religious and personal aspects!

How to Cull

There are a number of methods keepers use to cull hatchlings.  Some feed the hatchlings to other reptiles, feeling that death will be quick and the hatchling is providing some nutrition to another creature.  Other culling methods that have been recommended include use of a CO2 chamber, cooling and freezing, or bringing the animal to the vet for euthanization.  There has been much debate about which methods are humane and non-painful.

The Questions

Please let us know your thoughts and opinions by filling out the Response Box below.  Feel free to address the following questions or to bring up other issues not yet raised:

Under what circumstances should culling be done?

Should geckos be culled because of their genetic make-up alone?

What is the most humane method for “putting down” a gecko?

What are the ethical considerations with culling?

Is there any difference between considerations about ending a gecko’s life and ending a human’s life?

Comments are now closed. Thank you.


Gecko Time will publish the responses on June 11.



What do you think?

Written by Aliza

Aliza is a home care speech therapist living in the Boston area. She successfully bred a variety of gecko species between 2005 and 2017. She currently cares for a large number of geckos as well as a few frogs and bearded dragons. Other interests which she pursues in her copious free time include work in ceramics, practicing aikido and surfing the internet.

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