As pointed out in the question What temperature ranges are appropriate for a pet rabbit? temperatures above 85 °F (29 °C) are hazardous to rabbits. How can I help my rabbit stay cool in warm temperatures?
Domestic rabbits, are from rabbits native to Europe (Spain and Portugal), they are crepuscular, being most active around dawn and dusk. In the wild, they tend to spend the heat of the day in relatively cool underground warrens. Temperatures above 85F (29C) can be life threatening to them.
Optimally a pet rabbit will be kept in an air conditioned home, but this is not always possible. Options for supplemental cooling are:
- An electric fan that provides a breeze that the rabbit can enter and leave at will
- A bottle of frozen water that the bunny can snuggle up to (optional wrap in towel)
- A ceramic tile (available from DIY stores) provides a cool place to lay when temperatures temporarily get high during the day
- Ceramic tiles can be frozen and rotated in and out of the freezer for long hot spells.
- Cool water dabbed or wiped on a rabbits ears will moisten the hair and the evaporation will help cool the rabbit
When we are camping with our rabbits, we generally leave them in the air conditioned camper, while we go out and have adventures during the heat of the day.
Often a rabbit presence is required at an educational or fund raising event, where air condition is not available. Shade is important but is not enough when temp get high. In these cases we take a cooler with a few 1 liter sized frozen bottles. Some bunnies will snuggle next to them to stay cool, other bunnies dislike the condensation on the bottles. For the rabbits that don't like being next to the bottle of ice, I moisten my fingers with water (often the cool condensation) and rub it on their ears to help them cool down. A rabbits ears are a major part of their heat regulation system.
Although my rabbit doesn't seem particularly troubled by heat, sometimes I place a freezer pack atop his cage. It provides a cool downdraft and dripping cool water.
He does not like to sit or snuggle a cold object. Anything that's cold enough to stay cool to the touch on a hot day, will be either freezing after a minute's snuggle, or doesn't have enough heat capacity to last long. Once a bunny's butt has been frozen once, he won't be very inclined to sit on the same device again.
I wish to point out some other options I came across for cooling off rabbits in extreme heat, while the webpage does not refer to rabbits as Pets directly it does discuss solutions to cooling off rabbits that I do not see mentioned here including using Misters (a very common practice for cooliing animals and humans here in Phoenix). Also setup your hutches so they are under trees, this way there is no direct sunlight on the the hutch roofs radiating a high temperature.
Here is the web page with other thoughts on dealing with heat when raising rabbits.