Animal rescue groups are working overtime to find pets left behind in their owners' struggle to survive floods caused by Hurricane Harvey.

Austin Pets Alive saved hundreds of stranded dogs, including many from local shelters, which would otherwise have been euthanized. 

"The people in Houston especially weren't really prepared for this," Austin Pets Alive Executive Director Dr. Ellen Jefferson told "Fox & Friends" on Monday. "I think it caught a lot of people unaware, and they're just trying to save their own lives."

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Hurricane Harvey made landfall Friday, leaving the Rockport and Corpus Christi area devastated and dropping about 50 inches of rain on Houston. Those who tried to wait out the storm in Houston were left stranded in their flooded homes.

Emergency rescue groups' priority is human lives, but they have tried to save family pets whenever possible as well.

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