#data matters

The image reads: @WWF_Tigers: “More privately-owned tigers exist in US than wild ones in the world. WWF continues to call on US legislation to better control ownership of big cats, and prevent them from being laundered into wildlife trafficking rings #HoustonTiger” The image is a link to the CNN news story about the tiger. 

This is a problem. 

The number of tigers WWF is quoting here is 14 years old.

They’re from that one non-peer-reviewed census by Werner in 2005. As far as I can tell, WWF has been sourcing their 2008 “Paper Tigers” report for an estimated number of 5,000 tigers in the United States for the past 11 years. (Only 1,129 of those were actually in private or “pet” homes) The authors who wrote that report didn’t do their own census work on US tiger populations - instead, they used Werner’s 2005 paper as a major basis for their analysis, noted that it might not be completely accurate because of off-grid / hidden tigers, and ended by concluding there’s a “rough estimate of some 5,000 tigers in captivity” in the US. There has not been a single follow-up study in over a decade that has checked if those numbers are still accurate. (Except for mine, which indicates they’re not). 

More importantly, that report by WWF in 2008 found zero evidence that US tigers from the pet population were ending up in international black markets. They recommended a number of changes to the US regulatory system - like the closure of the generic tiger loophole in the Captive Bred Wildlife program - which have actually been implemented since, and laws about ownership and breeding of dangerous big cats in the US have only gotten stricter since 2008. It stands to reason that you’d expect less trafficking in that situation, not more. This assumption is reinforced by the fact that in all of the exposes about tiger farms and international black market trafficking of tiger parts published in the last couple years, not a single one even mentioned the participation of US entities or the involvement of US tigers! 

So, to sum up, WWF’s tiger account is tweeting out 14-year-old data and actively contradicting the results of one of their organizations’ own major reports. Apparently the “number of pet tigers in the US” is such common knowledge now that even international conservation organizations don’t need to fact-check it before they make public statements. 

Remember how earlier this year, I mentioned in a couple of posts that the claimed pet tiger population numbers in the United States just didn’t make sense? Well, here’s - finally - some published research on that! This piece is one of a multiple-part investigation into the messaging around the captive big cat crisis. 

To try to figure out where the incredibly high numbers of pet tigers were sourced from, I started tracking claims both in the media and academic publications back to their sources. And what I found, going back over fifteen years, is that basically none of the higher numbers actually had any solid data behind them. All of the academic sources continually cite a single census as being the most likely estimate to be accurate; it’s from 2005 and it found only a little under 5000 tigers in the United States. (The published version of the census includes basically no methodology, but having interviewed experts who were involved in the data collection for the census about where that information came from, I also agree that it was likely to be highly accurate at the time - even for the “off-grid” pet cats that didn’t show up in government databases). 

What becomes clear, when you look at all the claims across both the media publications and academic articles, is that over the last two decades, two different narratives developed with regards to pet tigers: conservation organizations like the WWF chose to stick with citing the most recent accepted academic data in their publications, and have not strayed from the estimate of 5,000 tigers since even though regulatory changes in the United States have likely decreased the number of pet tigers in the country; in contrast, animal advocacy groups and their peers inflated the numbers they chose to cite - assuming that there were still hidden animals that the 2005 census didn’t find - and tend to repeat their claims without referring to any sources that support their numbers. The media then goes to write a story on the “pet tiger crisis” and always consistently picks the highest possible estimate because it makes for a sexier story (without checking it’s veracity, because animal advocacy groups are assumed to be a credible source), and once those claims have been repeated by trustworthy news outlets like CNN and Business Insider they’ll be in the public consciousness forever.    

If you’re interested in seeing the evolution the tiger population claims in the media over the years, and where they originated, there’s detailed graphs in the linked article. When contrasted with the sources that have actual academic data behind them, there’s a very distinct difference. 

The tl;dr: Any claimed tiger population larger than 5,000 animals has no actual data to back it up. The last census of pet tigers that’s currently considered a credible source by academia was completed in 2005. Everything else is the result of a very complicated game of telephone in which mainstream reporters didn’t actually fact-check the claims they were repeating.