It looks like the forecast is for some hot weather .
And though the message about Dogs Die In Hot Cars / Don't Walk Your Dog in the Heat are well known , small fur covered rodents and lagamorphs are at high risk too .
There will be new pet owners this year who have never had a summer with a vunerable dependant animal so if this can help then great . Also if it's egg sucking tips for your granny then great .
But if it saves just one furry creature ......
Indoors or Outdoors . But especially outdoors where you cannot keep an eye on them 24/7
Wood and plastic are insulators so they warm up and hold heat
If they're in full sun they cannot escape the glare
Guinea-pigs especially like to hide in hay or boxes which insulates them further (I love them but they aren't the brightest
)
They need constant fresh water , maybe add an extra bottle .
Be aware too much salady food can make them loose . But things like cucumber , a bit of watermelon (and skin) , rinse a few leaves in water to give them extra moisture
Keep an eye on their bottoms - a loose pooh dirty bottom is a magnetic for flies (Flystrike is a grim and often fatal condition)
Prevention of heatstroke
Shade
Freeze a 2 litre plastic bottle of water , wrap in newspaper and place in the accomodation
Extra cage/hutch clean
A ceramic floor tile to sit on , nice and cool
We used to give them eating hay in a few toilet roll tubes or solid hay cookies , and less bedding . Shredded paper , fleece .
If they go out and it gets realy warm , a big towel wrung out (damp not dripping ) will create a cool breeze .
I had a couple of fitted sheets which made good run shades
Our guineas went out after the hottest part of day (their PigShed was lovely and cool in the shade of a tree) so they were cool in the day time
They loved prancing about after dusk........but so do foxes .
We had Fort Knox metal runs pegged down but you do need to check regularly for things digging in (they want to feed their young )
Guinea pigs don't dig but rabbits certainly can.
If you do get a heatstroked animal - pancaked flat , rapid breathing and lethargic - get them in a damp towel and off to the vet as an emergency
Check the lawn for those pesky weeds that are poisonous . Buttercups , daisies , .
And if I had a £ for everyone who said "Guinea-Pigs come from Peru , they can cope with -20c or 40c " I'd be mailing this from my villa in the Seychelles !
They are domestic so 'lose' a lot of their ancestors skills
Enjoy the sun and let them enjoy it too in safety .