It depends on each individual shelter and if/how they record that information. But I've looked at shelter data from all over the country and haven't seen much intake data where they indicate that the pet was turned in because the owner died. When I did see it, was a tiny fraction of the total, and I don't know how many were euthanized (the outcome may have been listed but it wasn't something we were looking at so I didn't record it) Most pets are in the shelter because they were lost or because their owners had housing issues.
There's a lot of open source animal shelter intake data shared online though, so you could start by looking at the shelters in your foundation's area and see what you can find. Or check a big city nearby, because larger metropolitan municipal shelters are more likely to share information online.
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M Saucedo
GIS Analyst
Pets for Life
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