Reptiles and Amphibians in Captivity - Breeding, Longevity and Inventory: a brief history

Reptiles and Amphibians in Captivity
Breeding, Longevity and Inventory:
a brief history

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Reprinted from International Zoo Yearbook (1989)28:7-9.

The Inventory of Live Reptiles and Amphibians in Captivity: a brief history

Frank L. Slavens
Curator of Reptiles, Woodland Park Zoological Gardens, 5500 Phinney Avenue North, Seattle, Washington 98103, USA

In 1975, as the United States was preparing for its 200th birthday celebration, I thought it would be an appropriate time to review what we, as keepers of reptiles, had achieved. A number of questions seemed pertinent: What had we done in the past 200 years: Are we still keeping 'postage stamp' collections? What species do we keep? Which do we breed and what breeding potential exists? Upon reflection it appeared that we did not have the means to answer any of these and I began to consider the production of an inventory of living captive reptiles and amphibians.

Letters were sent to 62 zoos requesting their inventories. Although only 23 responded, it was a start. I set up folders for each reptile and amphibian family with a single sheet of paper for each species reported. In the early years all the inventory information was compiled by hand. Breeding potential, based on numbers of known sex, was calculated in longhand. When all the data received had been entered and evaluated, the final results were presented in a typed 79-page report entitled "The Working Guide to Breeding Potential for Reptiles and Amphibians in United States Zoos, 1976. This was mimeographed, bound and distributed to institutions at no cost.

When the exercise was repeated in 1977 some 57 zoos responded and, again processed by hand, the typewritten information appeared in a 141-page document entitled "Inventory of Live Reptiles and Amphibians in North American Collections, current January 1, 1977. It took until July 1978 to compile and only 35 photocopies were distributed. When the inventory was again updated, in 1980, private breeders were included and more detailed information on reproduction was requested. A total of 82 collections responded (49 public and 33 private) and the resulting 156 typewritten pages were taken to a local printer for printing and binding. This enabled the data to be made more widely available.

The inventory had clearly become an annual event. In 1981 70 public and 90 private collections replied and the data covered 179 typed pages. Since the printer's bill was considerably more than was recuperated at the moderate charge made per copy, I purchased a very old printing press and a binding machine and, with the help of Eldon Slavens, the new volume was printed, collated and bound after sustained, and frequently frustrating efforts.

By the end of that year personal computers were becoming available and I purchased an IBM model. With a feeling that the computer revolution had arrived, I was ready to apply the new technology; to my dismay my computer did not have the slightest 'idea' what a Leopard gecko was; in fact it did not 'know' what a reptile was. Furthermore its memory was limited to 64K and databases were outside my understanding. Nevertheless a word processor was helpful in preparing the 197-page 1982 inventory which covered 176 (69 public and 107 private) collections and the 1983 inventory, covering 198 (75 and 123) collections. Data were now arriving from abroad and in this edition the words "in North American Collections" were replaced in the title by "in captivity". The volume, which included a new bibliography of husbandry and captive breeding, had grown to 254 pages.

The data recorded continued to grow and by 1985 I was not only taxing the limits of my word processor and printing press but also finding the task overwhelming. A considerable time was spent in setting up a database for handling the information. Kenneth Slavens helped me write the necessary programs to process the inventory, breeding and longevity data and because this greatly limited the time available only a single request for information was mailed. As a result the response was reduced from 260 collections in 1985 to 145 collections in 1986.

By 1987 I was able to evaluate and collate data from 307 collections representing 30 countries and produce the complete inventory with the aid of the computer. The final volume, 345 pages in length, featured inventory, longevity and breeding sections, which included descriptive information on successful breeding techniques from responding collections. The 402-page 1988 edition contains data from 400 collections. The breeding bibliography which was last published in the 1985 edition has grown considerably. It has not been possible to include it with the inventory report for the last few years but I hope to make it available soon.

Annual updates are planned for several years into the future. Keepers are asked to submit information as current on 1 January each year and are encouraged to include detailed longevity records and breeding results for the previous year. Titles of references relevant to reptile and amphibian reproduction are also requested.

Although ISIS has recently begun to include reptiles and amphibians in its stock records from zoos and other public collections, because of its individual specimen charges I fear that keepers will list only their most valuable animals, often a small proportion of the total stock. If the future response to ISIS is favorable and if private collections are included, an inventory may be available from ISIS. In these circumstances I would be able to concentrate my annual report on breeding, longevity and bibliographical records.

Anyone keeping live reptiles and amphibians is urged to contribute to the annual inventory which is summarized in appendix 1.

Acknowledgments: I am grateful to all those keepers who responded to the questionnaires each year. My thanks and appreciation also go to my father, Eldon Slavens, and my brother, Ken Slavens, for their many hours of help with this project

Appendix 1


1. A complete inventory of all reptiles and amphibians living in your collection as of January 1. Sexes of adult animals should be included and listed male (1.0.0) female (0.1.0) unknown (0.0.1). Juvenile animals should also be listed using the same format. For example, 1.2.1 + juv 0.0.10 would read: 1 adult male, 2 adult females, 1 adult of unknown sex, 0 juvenile males, 0 juvenile females, and 10 juveniles of unknown sex.

2. A list of all species bred during the previous year. Information may be sparse with simply and indication that the taxon was bred during the year, or it may be quite lengthy including, but not limited to: dates of copulation, dates of egg laying and hatching, types of substrates and temperature used during incubation, light cycles, hibernation, etc. Any type of valuable information up to three or four paragraphs may be used.

3. A list of all specimens in your collection which you believe may set longevity records for the species. List the date of acquisition; your specimen ID number; the sex; estimated age at capture; wild or captive bred; living or dead; there is also room for brief notes.

4. A list of any publications (including books, museum bulletins, journals, magazines, etc.) with reference to reproduction of captive reptiles and amphibians. Supplement the listing which appears in the 1985 edition.

5. Please be sure to list your name, address and telephone numbers as you want them listed. All information should be sent to Frank L. Slavens, P.O. Box 645, Lyle, Washington, 98635, USA.

Manuscript submitted 10 November 1988.

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