Hanging game birds is very common in the UK. All Pheasant shot in the UK are normally hung (whole and unplucked for several days). Pheasant are shot in the autumn here, the temperatures normally being <10C.
The idea of hanging is to improve flavour. Game birds can be pretty tastless if not hung or aged correctly.
I wasn't sure about hotter climates so I did a bit of research and came across this site.
It states (quoting good sources):
Pheasants hung for 9 days at 50°F have been found by overseas taste
panels to be more acceptable than those hung for 4 days at 59°F or for
18 days at 41°F. The taste panels thought that the birds stored at
59°F were tougher than those held for longer periods at lower
temperatures. Pheasants hung at 50°F became more ‘gamy’ in flavour and
more tender with length of hanging.
50F is about 10C. It does though also say:
Furthermore, an English study from 1973 found that clostridia and e.
coli bacteria form very rapidly once you get to about 60°F, but very
slowly — and not at all in the case of clostridia — at 50°F.
It ends with the advice:
- Keep your birds as cool and as separate as possible in the field. Use a game strap, not the game bag in your vest.
- Separate your birds in the truck or put them in a cooler — do not get them wet!
- Hanging your birds by the neck or feet does not matter, as several studies has shown.
- Hang the birds between 50 to 55°F for at least three days, up to a week with an old rooster. Old roosters will have horny beaks, blunt
spurs and feet that look like they have been walked on for quite some
time. They will also have a stiff, heavy keelbone. Hen pheasants only
need 3 days.
- Do not hang any game birds that have been gut-shot or are generally torn up. Butcher these immediately and use them for a pot pie.
- Dry-pluck any bird that has hung for more than 3 days. Wash and dry your birds after you pluck and draw them. Only then should you freeze
them.
This leads me to say that your correct that in a hot climate you may suffer potential disease when hanging birds or keeping them whole for long periods of time. I would suggest that if the temperature is 55F(12C) or above you should gut, pluck and get the carcass into cold storage ASAP, though this will limit the flavour when compared to a hung bird.