The burnings do not appear to be related or part of a trend, but the callousness of the attacks has sparked outrage and shined a light on the issue of animal abuse, Marano said.
Chloe was found June 24 in East Germantown, her entire face burned along with her belly and most of her legs; she died the next day at a New Jersey animal hospital. Hercules was found last Thursday in West Oak Lane with extreme burns on his legs and back, and suffering from smoke inhalation. He is receiving extensive medical care, including skin grafts.
Marano said Hercules' condition was improving. "He has started to eat on his own," and is no longer sedated, she said. "He's a little fighter, and we're all pulling for him."
PSPCA has a few leads in those cases, but no arrests have been made. Donations have poured in, allowing the agency to offer a $5,000 reward for information about Chloe, and $1,500 about Hercules.
"We're pretty sure there's somebody in the neighborhood who witnessed this," Marano said. "It's hard to set an animal on fire and not have someone notice it. The animals were probably whining and barking and crying."
Tips are crucial to solving animal abuse cases, said Sarah Speed, the Humane Society's Pennsylvania director. "These cases are extraordinarily difficult to prosecute because the victim can't talk," she said.
Witness testimony is sometimes the only way to prove that "the injury was inflicted, not accidental, and that it was inflicted by the person you are prosecuting," she said. But it can also be hard to come by.
In urban areas, there can be a "don't-snitch" mentality that discourages witnesses from coming forward, said Suzanne McAllister, a psychologist at the Animals and Society Institute, based in Jenkintown. "There's this fear that, 'If I can do this to an animal, there's no telling what I'll do to you,' " she said.
Under Pennsylvania law, abuse of domestic animals is a misdemeanor, punishable by up to two years in prison and a $5,000 fine. Other states distinguish between lower-level abuse, like neglect or abandonment, and torture.
The PSPCA receives more than 10,000 animal-abuse calls a year, Marano said, but the vast majority are cases of neglect, like malnourishment or leaving a dog in a hot car. "Extreme forms of cruelty like this do happen," she said, "but four cases in four weeks is a lot."
For McAllister, who runs a psychotherapy program for animal abusers, the cases bring to mind "the copycat phenomenon." Some perpetrators are looking for attention or a feeling of power, she said, and may be inspired to replicate what someone else has done.
"It's more likely," Speed said, "that the severity of these cases is catching more attention. ... This seems to be really sadistic individuals who are torturing animals."
There have been other recent cases of violence against animals in Philadelphia, including a man who set his neighbor's cat on fire, and a woman who doused stray cats in ammonia, killing one and sickening two. Those cases didn't garner as much attention, Marano said, because they had an obvious motive - the perpetrators were angry at the animals or their owners.
The burnings, she said, represent "a whole other mentality."
McAllister said this type of abuse indicated a lack of empathy that most people would find "appalling. They're so disconnected from their own feelings that ... it doesn't even compute for them that the animal is suffering."
She pointed to research "suggesting that people who abuse animals go on to commit other acts of violence."
The rally will be at 7 p.m. at 350 E. Erie Ave.
Animal abuse can be reported to PSPCA's Anti-Cruelty Hotline, 866-601-7722.
Contact Jessica Parks
at 215-854-2771 or firstname.lastname@example.org.