The campaign involves a scratchcard with an image of an oil spill on a coastline, which recipients are encouraged to scratch away with a coin to reveal a penguin.
The creative then asks for a donation by sending in the money used to scratch away the oil, with the strapline "the money you used to clean this bird, could clean this bird".
As well as raising awareness of the zoo's conservation projects the direct mail campaign aims to boost visitor numbers. Being targeted are regular supporters and visitors to the zoo as well as those living in a reasonable travelling distance to the Bristol area.
Brendon Veale, Bristol Zoo corporate and events fundraising manager, said: "We loved the idea of connecting the problem directly with the donation. Because it's interactive it will make people think about why they're donating, which all helps build awareness of our wildlife conservation work."
Chris Ward, Personal managing partner, added: "We wanted to create something that appealed to all ages and which was simple, engaging and effective."
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