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Chat Week 98 Transcript
12/10/98 - Harold De Lisle PHD

jeffb - good evening to Harold De Lisle PHD
Harold De Lisle - Good evening monitor lovers ... and others. I welcome scientific and technical questions, but since I am a slow typer, I will post detailed answers on the monitor forum over the next few days.
Harold De Lisle - my own research is on the behavior of monitors, especially relating to learning ability.
Harold De Lisle - I have 19 species at present

acanthurus - ok..I heard that since acanthurus are small monitors they are prolific breeders (prey items)...and I know beardies started off very expensive...but when they started mass prooducing the price dropped DRAMATICALLY...can you see this with acanthurus?
Harold De Lisle - I am NOT a breeder. In the wild, evidence is that acanthurus lat no more than one clutch per year.

Aredman - what species have you found to be most intellegent?
Harold De Lisle - Although my data stet is still limited to a few individuals of each species, I have found a kind of a tie between Crocs, bengals, and argus.

Boamaster - I just want to know where I can get a nice looking Green Tree monitor Male
jeffb - DnJ Reptiles
Boamaster - or does anyone want to buy my female.
Harold De Lisle - No more greens will be imported in the near future, There was a male available from Sunland Breeders a couple of months ago. $600

ChrisK - Dr. DeLisle: Please tell me what you know or what you theorize about the sources of vitamin d3 in Varanus. Do you have any idea how much of their d3 comes from UVB catalyzed synthesis versus dietary sources? Do you know of any literature on this specific topic?
Harold De Lisle - I don't know of any lit on the subject. I believe that most of their Vit D is synthesiized in their skin, as it is in most terrestrial verts.

dinopolis - I am wondering if the 19 species you have are yours or yours to study?And also,what determines the intelligence of one over the other in your studies?
Harold De Lisle - They are mine. I give them a number of the standardized tests, such as maze learning, that you give rats and other animals.

Duncan - What does the guest Feel should be done with the V. exanthematicus nomenclature?
Harold De Lisle - I am not aware of any exanthemiticus name problems. Please elaborate.
Duncan - as it deals with the white throat species/.subspecies problem
dinopolis - doh! the "s" word,lol
Harold De Lisle - Aha. Well, white-throats are DEFINITELY a separate species - albigularis. It has several subcpeices. There are presently no recognized subspecies of exanthematicus.
Duncan - Thanx
Harold De Lisle - Subspecies ... a big debate on another forum!!
jeffb - splitters vs. lumpers

Gorgo - What is the hatcling size for a crocodile monitor? What is the incubation time for the eggs (temp, and length of incubation)?
Harold De Lisle - I will have to get back to you on that, Gorgo. on the forum.

JamesA - I don't know much about Varanids but anyway how large do the crocs get ?All so what is a good book to get about crocs?
Harold De Lisle - Crocs get at least 9 ft., but it mostly tail. There is no BOOK on salavadorii, but several articles in mags exisst. One just recently in REPTILES

Jim - Do you know if monitors use pheromones in breeding? If so any information on the chemical nature of the pheromone - eg long chain ketone or alcohol?
Harold De Lisle - Yes, the work of Auffenberg indicates monitors use pheromones not only to indicate breeding condition but also to control much of the littlke social life they have, such as marking home ranges.
Harold De Lisle - Idon't think any of these secretions have been analyzed chemically.

JJ - How much prey would you estimate a wild Odatria eats in the wild on a daily average? What about larger species? How social are they in the wild (Odatria)?
Harold De Lisle - For monitors, its feast or famine. They will eat as much as they can catch, because tomorrow - maybe nothing!
Harold De Lisle - It's hard to do any averages.
JJ - Stomach counts?
Harold De Lisle - Stomach counts do not give you any idea of daily averages. That kind of a study would require regular flushing of stomachs.
Harold De Lisle - No monitors are really very social. Some tolerate the presence of others more than others - evening in the Odatria there is a big range of tolerance.

lisssa - yes,I am wondering if you have observed a higher level of intelligence in albigaris as opposed to say niloticus or other monitors
Harold De Lisle - No. I fear albigularis is toward the bottom of most of the tests I run.
lisssa - LOL ok I have one that is either real social or intelligent...'

marina - Several new monitors have been described just recently. Do you agree with the naming of these species or do you think some of them might actually be subspecific forms of previously recognized species?
Harold De Lisle - The two new monitors named in 1998 - yuwonoi and melinus - are very good, easily diagnosable species. Others are still in the works.

Mattmorelia - Do you feel the limited captive gene pool on some monitors (example: Varanus glauerti) will inevitably lead to a "dead" end of inbreeding? Is this even possible? (I've heard some recent developmental problems with some dwarf Varanids) I know it may be an "uneducated" question. I need to learn though! Thanks.
Harold De Lisle - I think you have a very good point. I know Frank R. will disagree vehemently, but if monitors are like most all other terrestrial verts., then inbreeding WILL be a problem in some of these lines with few ancestors.

Murray - What are the longevity numbers for monitors, esp. the nile?
Harold De Lisle - Most of the larger monitors live 20+ years. If I recall correctly, the official longevity record for a nile is 18 years. Smmaller species live less long.
Murray - I have a nile that is approching eighteen years old
Harold De Lisle - congrats! Be sure to report on it to the zoo people who keep these records.

Salvator - Will the Halmahera blue tail, the "blue" monitor, be given species status or become a subspecies of doreanus? Also do they have a final scientific name for these varanids yet?
Harold De Lisle - No official name yet. I suspect, because they are allopatric of all other blues, that they will eventually receive full species status. Allopatric means geographically separated.

Forest - Do you feel that recreating the atmospheric pressure of the wet season is a possible reason that S.E. asian forest monitors are so difficult to get to reproduce in captivity?
Forest - Specifically monitors with prominent sinus cavity.
Harold De Lisle - That is a very reasonable hypothesis. But it may be even more complicated than that. It seems some monitors can hold off egg laying until just the right amount of moisture has fallen to give the eggs a chance.

t-rick - I have a pair of albigularis,that I'm going to be housing outside.Should I keep them together or separate prior to breeding? And why?
Harold De Lisle - In the wild they live quite separately. When the breeding season comes, the male sets off to locate the females. See if you can duplicate this in some way, my suggestion.

Pyro - Earlier you said varanids are amoung the most intelligent of lizards. I suspect this is a well known fact that everyone just accepts. But what sort of clues have they given that indicate their high intelligence? Have studies have been published on this matter? That differs from other lizards.
Harold De Lisle - No studies published yet. Data are too scant. But in all the standard learning tests they do best. Of course, I am defining "intelligence" as the ability to learn.
Harold De Lisle - An ackie can find food at the en d of a maze at least 10 times quicker than a leopard gecko.

Aredman - with all the restriction's on importation lately, how will it effect us herpers on buying them in the future? i know you don't breed yourself but i'm just curious of your opinion
Harold De Lisle - I am also very concerned. I have to get my specimens the same way as the rest of you. I hope Indonesia gets its house in oreder soon.
Harold De Lisle - It is also nonsense that bengals are on appendix I. They are one of the commonest lizards in se Asia.

Artrellia - Do you think there are any larger subspecies of salvadorii still undiscovered? What is the temperature of heating salvadoriis' eggs? I got a clutch of 8 eggs about 2-3 weeks ago.
Harold De Lisle - Congrats on that clutch. It's on the large size. I doubt if there are any subspecies of salvadorii.
Harold De Lisle - No info on inccubation temps. Ask Frank R.
Artrellia - Thanks i'll keep you posted about the eggs
Harold De Lisle - I friend of mine lost a clutch of 4 salavdorii. Very touchy.

Duncan - Harold De Lisle, can you post a cite for the official naming of Aalbigularis as a sep. sp..?
Harold De Lisle - Albigularis was named all the way back in 1802. It was just that Mertens (THE monitor god) did not recognize it as sperarte. Bohme in 1988 set it straight.
Harold De Lisle - Bonn. Zool. Monog. 27:1

Forest - Have you heard of any sucessful breeding of V. melinus yet? I know eggs were laid from wild caught gravid females,but how about new breedings?
Harold De Lisle - No haven't heard anything. I suppose it's too soon for even wild conceived eggs to hatch. Monitos have a LONG incubation period. 6 months for the larger species, at least.

Igmom - I was late getting here so you may have answered this.....what is the easist monitor to keep in captivity for the average reptile enthusiast? regard to housing, feeding, lighting
Harold De Lisle - For a beginner, I recommend a savanna. They a cheap, relatively docile, and easy to feed etc. Of course, they do require a larger cage than the small ones like acanthurus.
jeffb - I use a metal horse trough for mine
jeffb - it looks kinda strange in the living room
Harold De Lisle - I use a very wierd assortment of cages myself.

Igmom - Does acanthurus have a more common name....JeffB LOL No stranger than igs in my dining room!
jeffb - red ackies
jeffb - ackies
JJ - spiny-tailed monitors
Igmom - Thanks!

JJ - Whay don't you breed your animals? (assuming the above statement was true)
Harold De Lisle - Too many other irons in the fire. You need lost of space to breed monitors. I have always been very limited that way.

Ophidiophile - I work summers in Papua New Guinea about 30 miles in from the north coast
Ophidiophile - and 40 miles from the Irian border. People often catch monitors there
Ophidiophile - that look very argus-like but have vaguely blue tails. I'm wondering if they're argus or blue-tails. Not much is known about this particular area.
Ophidiophile - Any ideas?
Harold De Lisle - Nice. I have been to Irina Jaya once - Jayapura
Harold De Lisle - You were not far from me,
Harold De Lisle - Ground or trees?
Ophidiophile - Arboreal mostly
Harold De Lisle - They are then most likely doreanus, which is fairly common along the north coast. That is, blue-tails.
Ophidiophile - I thought they were likely doreanus. Thanks
Ophidiophile - Pretty vague data to go on I know - sorry

midy - what is the avaliability of blue tails in the US?
Harold De Lisle - From what I hear, few Indonesian monitors of any kind are avauilable in the US right now.

marina - I have another question, too: Here at UT Arlington, there is a student who does work on learning behavior in gould's monitors. But, she's a psych student. Does your work fit more in the realm of biology or psych and why?
Harold De Lisle - Well, I consider it neuroBIOLOGY.
Harold De Lisle - I look at behavior from a biological aspect.
marina - Hm. Our neurobiologists like to get right at the brain. ;)

JJ - Do you work with mainly indo species or others too?
Harold De Lisle - Others too

JJ - Do you keep them in naturalistic vivaria?
marina - Thanks. I just don't know much about your work and wanted to find out more.

jeffb - thank you for being our guest Harold De Lisle

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