Monitor Care & Natural History; Zoo & Pet Experiences

[_Varanidae_]

Murrindindi,

The scientific study linked to on the first page of this thread answers many of the questions you are asking. It reports the cause of death for 85 monitor lizards kept by the Bronx Zoo over the past four decades, even breaking the data down by species- and discusses the data's implications for husbandry and reproductive management.

[murrindindi]

Originally Posted by _Varanidae_

Murrindindi,

The scientific study linked to on the first page of this thread answers many of the questions you are asking. It reports the cause of death for 85 monitor lizards kept by the Bronx Zoo over the past four decades, even breaking the data down by species- and discusses the data's implications for husbandry and reproductive management.

O.k, thanks for that, I missed it. (That`s been a recurring problem of mine)....
Edit: It`s only showing the abstract, I`ll have to order a copy from the library.

[jarich]

Stefan, Im pretty sure Robert would send you a copy if you give him your email.

[murrindindi]

Originally Posted by jarich

Stefan, Im pretty sure Robert would send you a copy if you give him your email.

Thanks, I have contacted Robert previously, though I bet he`s forgotten already!

[_Varanidae_]

Frank, judging by your comment about working at the zoo when Sam Lee first started, I take it you haven't been with the BZ herp dept. since the mid/late 1990s? While I am not sure where your career took you after the BZ, you may have missed out on some important publications and improvements made in the fields of varanid biology and husbandry since then. Several have introduced paradigm shifts in the way monitors are kept.

For example, although a controversial figure in the monitor community due to his abrasive personality, Frank Retes played a pivotal role in the advancement of monitor husbandry during the 1990s and was one of the first to employ basking temperatures which were much hotter than those deemed acceptable by convention at the time. This was a major game changer, and enabled many more monitor species to be bred with greater frequency than in years and decades past (and to multiple CB generations). Here is the citation of the article which first introduced this idea of HOT basking sites which I highly recommend checking out:

Retes, F. & D. Bennett. 2001. Multiple generations, multiple clutches, and early maturity in four species of monitor lizards (Varanidae) bred in captivity. Herpetological Review 32(4): 244-245.

This is not to say that these changes were readily adopted or welcomed with open arms- there were many skeptics and opponents of this approach for quite some time. Prior to this shift, yes, some monitors were bred on occasion in zoos and private collections (the review articles by Horn & Visser, 1989, 1997 provide excellent overviews of breeding in the past). However, if you were to look closely at earlier published accounts of reproduction, you will see that egg viability was terrible (it still is today in many zoos; low viability was also seen at the BZ- see: Reproduction of varanid lizards (Reptilia: ... [Zoo Biol. 2012 May-Jun] - PubMed - NCBI), eggs were rarely nested properly- scattered instead atop the substrate or in water basins, and successful cases of breeding were rarely, if ever repeated, and almost never on a consistent basis. While some of these issues are still present today, conditions have much improved since before this shift in the way heat is provided to monitors.

Upon talking with many colleagues in the zoo field while undertaking the three zoo-based varanid studies I conducted while at the BZ (the third- a study on life expectancy and longevity in zoos is forthcoming), I was shocked to learn that most zoos were not familiar with the publication above, or any of the other more recent publications that have helped improve standards of varanid husbandry over the last 10-15 years. As I mentioned above, taxon management accounts currently in use by zoos for studbook species were compiled in 1996, and clearly exemplifies this issue.

Chronic dehydration is another major problem in captivity (this actually gets more attention in our retrospective study), and is highly relevant in cases of gout. Considering that most varanids originate from either very humid environments or arid environments where they spend large amounts of time inside burrows and other retreats where the air is at or near saturation, screen cages or exhibits with large areas of ventilation and shallow substrates have not cut it. The conditions these types of setups produce can accelerate the rate of evaporative water loss and dehydration in captive monitors. Chronic dehydration can lead to gout and other physiological disorders, and ultimately death. As our study reports, 50% of V. melinus, 33% of V. griseus (a strict desert-dwelling species!), and 33% of V. varius died of gout at the BZ. Temperatures and humidity levels are a big deal and heavily tied in to the success of varanids in captivity.

If anyone is interested in reading more, I'll gladly send you both research articles dealing with varanids at the BZ.

Best,

Robert

[crocdoc]

Originally Posted by bronxzoofrank

...am starting to see personal criticisms which I will not address in any event.

There is nothing personal in these comments. It's simply a matter of what we know about varanid husbandry having changed over the years and those low basking temperatures are known to result in issues. When new keepers see a blog by someone that says they have worked at major zoos, they may try to copy the techniques outlined in your care section and that will lead to trouble for their monitors. We have a responsibility to ensure people start out on the right foot.

Originally Posted by bronxzoofrank

while there are and will always be problems, exceptions to the rule...Again, there are a number of ways to go about providing proper care

The exceptions to the rule are the monitors that fare well at those low basking temperatures. You'd be surprised at the difference when monitors are kept at higher basking temperatures. They feed better, grow faster, live longer and will breed readily. There may be a number of ways to go about providing proper care, but if one has been proven time and time again to be better than another, it is best that one puts that technique into a care sheet.

[fuzzhc]

Whilst my input wont mean much as im a fairly new savannah owner just thought id share my experience. When I first got mine I followed the pet shops and various websites guidelines with a lower humidity, sand and a basking area of 95-100 degree F.

A few months past and my monitor was worse for wear. He was sluggish, spent alot of his time in his water bowl and ate maybe a few crickets every couple of days at most and hadnt grown a single inch since I first got him.

When deficating which wasnt very often, it would always be in his water bowl. Since then I have been given the great advice to bump up the temps, humidity and a deeper substrate. At 60-70% humidity and a 140 basking area he has improved beyond belief.

He is very active and is growing like wild fire eating 2-3 small sized mice and a load of locusts and worms every day. Heck ive even got him hand feeding every day now and doing death rolls to prize the food from my tongs. I would highly recommend giving the higher temps and humidity a go.

[philipniceguy]

while I of course have never been to BZ I however have been to many UK based zoos and I yet to find one that has healthy active monitors on show. I sure some zoos are trying new stuff but very few of them which is very upsetting as they have the time, money and resources to pretty much do anything. If I had that sort of money and space I sure I would be going the extra mile toward groundbreaking new care.

[infernalis]

Why has this thread fell silent?

[murrindindi]

Originally Posted by infernalis

Why has this thread fell silent?

Perhaps the OP`s pride got in the way of progress (discussion)...
If "they" won`t listen how will it ever change??

[infernalis]

Originally Posted by murrindindi

Perhaps the OP`s pride got in the way of progress (discussion)...
If "they" won`t listen how will it ever change??

I have the utmost respect for Frank's past & his career, I just really wish his opinion was not immovable.

Scientific research & private experiences have since proven that elevated temperatures, paying attention to humidity and deep soil substrates produce far healthier / robust Varanids in captivity.

History has also proven that under metabolised Varanids become lethargic, obese and their organs fail prematurely.

Three of the worlds leading Varanid specialists, with enough books, telecasts and research papers among them to build a small library have also pointed out the very same observations.

[bronxzoofrank]

Originally Posted by murrindindi

Perhaps the OP`s pride got in the way of progress (discussion)...
If "they" won`t listen how will it ever change??

Please see comment#29; I'll read some of the forwarded articles when possible; cannot comment on these studies without reading...given what I know of note-taking/daily log entries at the zoo, hard to imagine how studies can accurately examine deaths dating back 4 decades, but, again, I'll need to read the articles. It will take some time, no point in my commenting until then..

[bronxzoofrank]

Originally Posted by Akuma223

I really don't understand why this guy is so foolish as to not change the obvious faults with his care :/ In the short time I've had my Rudicollis its very clear which temperatures work best. He seems to be doing more harm then good because of his obstinateness.

Please refrain from personal attacks

[murrindindi]

Originally Posted by Akuma223

I really don't understand why this guy is so foolish as to not change the obvious faults with his care :/ In the short time I've had my Rudicollis its very clear which temperatures work best. He seems to be doing more harm then good because of his obstinateness.

Hi, I`m not sure if Frank Indiviglio keeps monitors himself, he only stated he`s worked with them, but he does author the care guides which obviously need updating.
He did say he was very busy and would look into the points raised, so maybe he will return again quite soon?

[bronxzoofrank]

Originally Posted by murrindindi

Perhaps the OP`s pride got in the way of progress (discussion)...
If "they" won`t listen how will it ever change??

Please do not comment on my perceived personality traits, pl see earlier response to this post also.