Do bottles with blue-tinted water repel stray dogs and cats?

A resident from Malolos, Bulacan, was left puzzled after his neighbors began leaving bottles filled with blue-tinted water outside their homes.

According to Kuya Kim's report on "24 Oras," Thursday, the residents would add bluing powder to the water to give it its blue hue.

"Hindi ko po alam kung sino 'yung nagpasimula, pero nakita na lang po namin na may mga gumagawang kapitbahay. Parang nag-spread, lahat po gumagawa," said Reymond Vitalla.

One neighbor, Leopoldo Santos, shared that they started putting out the bottles to repel stray dogs and cats from urinating in their area. But this only seemed to ward off the animals at first, as the strays eventually came back to urinate and defecate in their area.

According to Kuya Kim, this practice isn't unique to the Philippines. Some people in India also leave out water bottles filled with colored water in an attempt to repel strays. The practice is also done in Spain, Japan, Argentina, and Mexico, where some use bottles filled with plain water.

The Japanese, in particular, call this practice "nekoyoke" or "scare-cats."

Per Kuya Kim, some theorize that cats and dogs get scared to get close to the bottles when these refract light. Another theory could be that dogs do not like the smell of the bluing powder.

But does the practice actually repel stray cats and dogs?

Dr. Sean Evan Javier, a veterinarian, said there is no evidence to prove this is true.

"Wala pang napapatunayan na 'yung paglalagay ng tina o kulay asul talagang makakapag-deter sa mga galang aso," Javier said on "24 Oras."

It is also unknown where this practice originated.

— CDC, GMA Integrated News