Another factor is lifespan. Wong says hamsters have a short, two-year life expectancy; rabbits will keep thumping for about nine years; dogs can wag their tails for about 15 years; cats might purr for up to 20 years; parrots can keep singing for 80 years; and terrapin turtles have the longest lifespan, rounding out at a century.

With five adoption centres (Wan Chai, Kowloon Centre on Princess Margaret Road, Mong Kok and two centres in Sai Kung), the SPCA has approximately 100 to 120 animals waiting for homes.

It costs HK$400 to adopt a domestic short-hair cat, HK$550 for a pedigree or long-hair cat, while mixed-breed dogs are HK$600, and pure-breed dogs will set owners back about HK$1,000, depending on the breed.

The adoption fee for dogs, cats, rabbits and chinchillas includes a veterinary check-up, de-worming and de-fleaing, vaccinations for the first year, micro-chipping and desexing. Dogs also receive a heartworm test and rabies vaccination.

Wong recommends looking through the animal adoption section on the SPCA's website. Then potential owners should visit the centre to interact with the animal.

'When people look at a picture, they always think the animal looks cute, but in reality dogs can jump up, bark, scratch, play fight and of course pee and poo,' Wong explains.

Potential owners need to provide proof of address. The SPCA will then check that pets are allowed. 'Some private or public estates don't allow pets and we don't want a pet to be adopted, only to eventually get kicked out,' Wong says. Tenants of rented apartments also need to obtain a document from the landlord that states animals are permitted.

The founder of Hong Kong Dog Rescue (HKDR), Sally Andersen, says the charity has about 400 animals waiting for a new home. To start the process, applicants must fill out a questionnaire to see if the new home is suitable and what breed would be the best match.

While the HKDR is always looking for new owners, its turns down 'a lot' of potential adopters. 'There are two main reasons: one is that the dog would be left alone all day while the owner is out at work; and the other is not enough exercise. Some people never walk a dog, or only once or twice a week, which is common,' Andersen says.

She adds that getting a dog should be a family decision and should never be because a young child wants one. 'Next week [he or she] will want something else ... dogs are a long-term [commitment] and if you can't guarantee to look after one for 15 years plus, then foster instead.'

Where to adopt: