Lisa Medwid, a film producer in Los Angeles, Calif., spends a lot of her time on the studio reading scripts and taking meetings. But not everything Medwid does on the lot is film project-related. She also sets up cages in and around sound stages so she can humanely trap feral cats and have them sterilized before returning them to their environment. "It's frustrating, because no matter how many cats I find and get to the vet, it seems like there is always at least one litter of feral kittens somewhere on the lot," Medwid says. "I've been here more than 10 years and I've never seen anything like this."

Medwid is not the only one who has noticed a sudden jump in the cat population. Shelters and rescue groups across the country are seeing a drastic increase in the number of litters being delivered to their doorsteps. While a few different factors influence such population increases, many experts suspect climate change is helping to fuel the kitty birthrate explosion.

According to Nancy Peterson of the Humane Society of the United States, the feline breeding season is impacted by temperature. She says, "In warmer climates, cats breed three times as opposed to two times a year. And as it gets warmer, they could breed even four times a year."

What you can do:
Medwid's advice to pet owners? "Spay and neuter your animals! With feral cats, it's pretty much out of our control, but if all pet owners would spay/neuter their kittens, we could go a long way towards getting the cat population under control."

Unfortunately, feline birthrate changes are not the only way global warming may be affecting our pets.

Fleas and Ticks
Few would disagree that fleas are a huge nuisance. But, you may not realize or worry that fleas, as carriers of fatal diseases like the Plague, could potentially become a serious health threat in the years to come. According to the Centers for Disease Control, cats, which catch the Plague from fleas, can transmit the disease to people. The Plague actually refers to a few different illnesses, the infamous Bubonic Plague being one of them. All are bacterial infections transmitted by parasites.

Other vector-borne diseases, such as Lyme disease (spread by ticks) and West Nile Virus, are linked to the seasons. With warmer weather occurring over a longer period of time, there is more opportunity for these diseases to spread. Although incidents of the Plague have been limited predominantly to the southwestern region of the country in recent years, a warmer climate could cause that to change. A foreboding sign is that this has been one of the worst years in recent history for fleas.

Andy Selfe, an equestrian in Warrenton, Va., who diligently administers flea control products to her cat and dogs, says, "From May on, the fleas were completely out of control. They were everywhere this summer and they got on everything and everyone." In July, she was one day late in applying a flea control product to her cat, Tom. Selfe says her pet became covered in fleas after she held him for only a few minutes.

What you can do:

• Be diligent about administering your cat's flea treatment on the proper schedule.
• Do not allow your pet access to the outdoors, especially to wooded and tall grass areas where ticks and fleas thrive.
• During the warmer months, check your pet daily for ticks.

Take precautions, but don't go overboard. Peterson warns, "You should be really careful when administering flea medication. Consult your vet so as not to overdose your pet -- for example, by applying topical treatment, using a flea collar, and then treating your home."

Exposure to Extreme Temperatures and Weather
One of the more bizarre effects of global warming is freak cold spells and colder temperatures in some parts. According to Bonner Cohen, PhD, a senior fellow at the National Center for Public Policy Research in Washington, D.C., "The climate will warm up in some places and cool off in some places."

You may have also noticed an increase in hurricanes. For pets in areas prone to these storms, the weather conditions can be deadly. And, of course, there are the higher temperatures to contend with, which put your pet at greater risk for developing heat stroke.

What you can do:

• Keep your cat indoors at all times.
• Never leave your pet exposed to the elements or inside the car in extreme temperatures.
• Always make sure your pet has access to plenty of water.
• Make arrangements for your pet now in the event of a natural disaster.

The Good News
According to Cohen, "Cats exhibit remarkable success at weathering the various changes the climate has gone through. They have been through three ice ages and the global warming periods that followed." Global warming's full effect on domesticated cats, however, remains an ongoing, worldwide experiment. With a little precaution and care on your part, your cat has a much better chance of weathering the changes.