The unfortunate reality is that we have far fewer butterflies than we used to, with some species becoming "locally extinct" (lost from a given region). The main culprit is habitat loss, with fields becoming more-intensively farmed and land given over to developers, for example. Even commoner species are feeling the pinch. Another factor is climate change which, although beneficial for some species, has resulted in unsuitable conditions for others. But it should also be remembered that certain species, such as the Red Admiral and Painted Lady, are primarily the result of immigration of adult butterflies from the continent. Their numbers therefore naturally fluctuate from year to year.
Several species of butterfly hibernate in the UK - Brimstone, Comma, Large Tortoiseshell, Peacock and Small Tortoiseshell. In recent years, with climate change, we're also starting to see the successful overwintering of Clouded Yellow and Red Admiral. Such species tend to look for sheltered areas in which to hibernate, which is why they are sometimes seen in houses and garages. However, an unnaturally warm environment, such as a house that is centrally heated, can be quite detrimental since the butterfly will become active and use up the essential body fats that will see it through the winter. The best thing to do is to be "cruel to be kind". One option is to place the butterfly in a cold and dark environment and out of the way of predators, such as in a log pile, an outhouse, or a hollow tree. Alternatively, on the next sunny day that is sufficiently warm, release the individual outside so that it can find a more suitable location in which to hibernate itself.
There are so many variables that will help determine the likely candidate - size, colour, location, time of year, and so on. But the best starting point is take a look at the Identification page which can be accessed by Clicking here.
Select the species you're interested in finding from either the Home page, or one of the species family pages. The "Distribution and Sites" section found on each species page links to a page containing a map of the UK, showing the distribution of the species, and any specific sites where this species can be found. Also see the next question!
Select the species you're interested in finding from either the Home page, or one of the species family pages. The species page contains a chart showing the time of year when each stage can be found.
Select the Flight Times - Sorted by Date link, which is found under the "Species" menu. You'll be given the option to look at typical flight times, as well as earliest flight times.
The site information contained in this website is fairly extensive and may well contain the specific site you're interested in. The first place to start is the Sites page, which is found under the "Species" menu. On this page you can select a particular grid square which will take you to a separate page containing a map of that square, the sites in that square, and the species found at that site.
Select the Larval Foodplants link, which is found under the "Species" menu.
Select the species you're interested in from either the Home page, or one of the species family pages. Larval foodplants are listed on each species page.
Select the Nectar Sources link, which is found under the "Species" menu.
Select the species you're interested in from either the Home page, or one of the species family pages. Nectar sources are listed on each species page.