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willbenn
03-05-2010, 10:48 PM
not sure exactly where this thread should go but since people oftne mention destruction of wild populations on this forum i figured its as good a place as any.

with the several smugglers that have been caught over the past few months, there has been a lot of talk about how smugglers contribute to species becoming threatened or possibly extinct. this has gotten me thinking. ive been racking my brain trying to come up with some species of gecko (or even other reptiles) that have become threatened due to collection solely for the pet trade. im sure there are some but i cant think of any off the top of my head. im not talking about collection for food or by-products, im talking strictly for the live pet trade without other factors involved like habitat destruction or introduction of non native animals. there has to be some in areas of asia and possibly northern africa. can anyone enlighten me?

Ruru
03-05-2010, 11:15 PM
I don't think there would be any species affectd by the pet trade that haven't also been affected by habitat destruction, predation by introduced species or predation by humans. Good luck in your search!

willbenn
03-05-2010, 11:22 PM
ruru - what about if we count some habitat destruction and introduced species, can you think of any that are mainly affected by collecting? i honestly cant think of any. there are certainly local populations that are strongly affected by collecting but if a range is so small that collection is potentially threatening to a species, that species is already in BIG trouble

danscantle
03-06-2010, 01:16 AM
I can't think of any. A couple of sketchy Europeans vs. Rats vs. Habitat destruction. Some are probably worse than others...

luc
03-06-2010, 07:39 AM
not sure exactly where this thread should go but since people oftne mention destruction of wild populations on this forum i figured its as good a place as any.

with the several smugglers that have been caught over the past few months, there has been a lot of talk about how smugglers contribute to species becoming threatened or possibly extinct. this has gotten me thinking. ive been racking my brain trying to come up with some species of gecko (or even other reptiles) that have become threatened due to collection solely for the pet trade. im sure there are some but i cant think of any off the top of my head. im not talking about collection for food or by-products, im talking strictly for the live pet trade without other factors involved like habitat destruction or introduction of non native animals. there has to be some in areas of asia and possibly northern africa. can anyone enlighten me?
Two species that became endagered because of the pet trade are shinisaurus crocodilurus and corucia zebrata.

willbenn
03-06-2010, 11:20 AM
luc - both are good examples, but i question whether either species became endangered mainly from collecting. both species have also been heavily affected by other factors like deforestation. a good question is - if people had not collected those species, would they still be endangered?

i could be wrong but i think shinisaurus were threatened/endangered before they became popular in the pet trade. the numbers were definitely in decline from habitat destruction and pollution.

the zebrata is a good one. they were exported in large numbers before they received CITES II status.

oli
03-07-2010, 07:27 PM
what about some of the australian species where habitat destruction is less of an issue like the n. deleani for instance?

tanala
03-08-2010, 04:58 AM
after the description of Goniurosaurus luii and araneus, some populations declined drastically due to massive collecting. I dont know if they recovered, nor if these populations are affected by habitat destruction etc. Another species that could suffer is Lygodactylus williamsi. I have another example: there was concern that some Mantella species (frog genus from Madagascar) are threatened because of over-collecting. However, several studies couldnt show that - even in areas with high collecting pressure, populations seem to be stable. But Mantellas are a different kind of animal group. It seems they can recover by a high reproduction rate. Geckos dont have high reproduction rates, so if looking after influences on populations of animals that are of concern to the pet trade, you have to take many aspects of their life history into consideration.

Sebastian
03-10-2010, 04:05 PM
ive been racking my brain trying to come up with some species of gecko (or even other reptiles) that have become threatened due to collection solely for the pet trade. im sure there are some but i cant think of any off the top of my head.

As already mentioned Lygodactylus williamsi is a good example. This species lives in an extremely small area and thousands of them have been exported.These days they are sold at a loss. (for 20-50 USD)
At the moment I don't think that CB williamsi can counterbalance that and future will show if it is possible to list them on CITES.

willbenn
03-11-2010, 11:36 AM
oli - n. deleani does have a small range but i was actually told by an aussie herper that deleani are fairly common in their range.

tanala - the goniurosaurus are an interesting possibility. the l. williamsi are also greatly affected by deforestation. and i would think everything from madagascar is more greatly affected by habitat loss/deforestation than collecting. from what i have read, over 80% of the islands original forest is gone.

willbenn
03-11-2010, 12:00 PM
what about some species with an extremely small range? some of the newly described aussie leaf tails are said to only occur in one small mountain area. fortunately for them, i can't imagine they could be over collected due to australias restrictions. what about species from countries that don't have serious restrictions?

sebastian - you mentioned that l. williamsi has a small range. do you think collecting is more harmful to their population than the deforestation that is happening within their range?

Sebastian
03-11-2010, 06:19 PM
sebastian - you mentioned that l. williamsi has a small range. do you think collecting is more harmful to their population than the deforestation that is happening within their range?
I know ppl who have been there to study the situation of L.williamsi and I definately think that collecting is much more harmful to them than any other issue.

willbenn
03-13-2010, 09:14 PM
sebastian - thanks for the info! they are an incredible colored species so the huge interest in them does not suprise me one bit. it would be a shame if they dropped to critical numbers because of their popularity so let's hope captive breeding efforts can take some pressure off

DJreptile
03-18-2010, 10:38 PM
So after a brief search of a couple of databases I could not come up with any papers addressing the situation you're putting forth.

I honestly think the idea of a population of any organism only being influenced by collecting for the pet trade is purely hypothetical. You're not going to find anywhere with collecting being the sole pressure on a population. Even with Corucias and Shinisauri at the very least you're looking at animals which are used by the local populace for food. In China there's also the rampant pollution and population growth everywhere so I don't see how a solid argument for collecting as the primary pressure on Shinisaurus populations can be made, and the Solomon Islands are so small and host to invasive rats, cats, and dogs all of which are animals I can see exerting a strong competitive/predatory pressure on Corucia populations, and if Fire Ants have made it there in their journey across the South Pacific then they're definitely going to be a problem for all the native wildlife.

It seems to me collecting really becomes an issue when it is an additional pressure on top of things like habitat destruction and invasive species. You see a similar pattern in fishery management where species can endure large harvests with little/no discernable impact but the second a developer fills up the one salt marsh where a species goes to spawn, or pollution fouls the food chain causing massive plankton die offs then all of a sudden previously sustainable levels of harvesting have a dramatic impact on population numbers.

Of course one could argue collectors are what save species. All it takes is a handful of dedicated hobbyists to create a self sustaining captive population while the wild ones are having there habitat brought down around their ears. For most of the smaller, more obscure species hobbyists are the only ones who will even bother with them. Zoos have limited budgets and thus have to focus on what will bring people through their doors and hope they make a little extra money to support work with some of the other species while academic institutes are concerned primarily with expanding their collections of pickled animals and publishing papers. You're not going to find many researchers out in the field bringing home breeding groups random little geckos or little brown frogs to start breeding because the forest where they were found is being bulldozed as we speak. It's the random collector who happens to see that little geckos or little brown frog and falls in love with it that will spend the time and money necessary to see a viable captive breeding population started.

So, while I'm willing to accept collecting for the pet trade as one pressure on wild populations of herps I've noticed a dearth of good scientific research into the matter and analagous situations, like fishery management, seem to suggest habitat/environmental maintenance is the key to preserving species and it is only after the habitat has been compromised that a species becomes susceptible to additional pressures. Which is why it irritates me to no end when I see people bashing the pet trade. There's no science behind it, just a host of assumptions and an unwillingness to examine the real issues of habitat loss, and how our chosen lifestyles are the driving force behind said problem.

*steps down off soapbox*

willbenn
03-19-2010, 01:47 PM
DJ - i couldn't agree with you more. these reptile species have been around for many, many years because they have adapted to natural pressures like predation and temporary habitat change. if a fire burns down a wooded area, that habitat eventually grows back, but if its cleared for agriculture/farming, or human population expanse, its gone for good. with collecting, the collectors only see a very small percentage of a population and are thus limited in the numbers they can collect. its all part of the natural predation model, the geckos that are less wary and make themselves more vulnerable to predators (both animals and humans in this case) will be the ones that are eaten, or caught. the ones that are more wary and cautious are the ones that will pass on their genes and better the chances for survival of the species. the problem is when humans alter habitat and make it no longer viable to its inhabitants. whether its by habitat destruction, landscape alteration (i.e. builing dams or rerouting water flow), pollution, introduction of non-native/invasive species, etc etc, it generally causes major problems for the species that have evolved/survived in that area for thousands and thousands of years.

bottom line, reptile species don't become threatened/endangered solely by collecting/poaching for the pet trade. now if you're a black rhino or an animal that stands out like the las vegas skyline, then poaching is certainly an issue.