Festuca species), and meadow-grasses (various Poa species). Common couch (Elymus repens) is also used. Nectar sources Adults feed primarily on bramble (Rubus fruticosus agg.), carline thistle (Carlina vulgaris), devil's-bit scabious (Succisa pratensis), fleabane (Pulicaria dysenterica), hemp agrimony (Eupatorium cannabinum), wild privet (Ligustrum vulgare), ragwort (Jacobaea vulgaris), red clover (Trifolium patense), thistles (Cirsium and Carduus species), thyme (Thymus praecox), and water mint (Mentha aquatica). Behaviour Activity The gatekeeper butterfly tends to rest on vegetation during overcast or hazy sunshine conditions. During sunny weather, it flies from flower to flower gathering nectar. The gatekeeper is a relatively active butterfly, but not very mobile, as seen when comparing it to a similar species, Maniola jurtina. Mobility in butterflies refers to the distance covered from flying, while activity refers to how often they are in flight. In an experiment assessing wing damage, P. tithonus showed faster wing damage as a result of their increased activity, and these results showed that activity levels do not necessarily correlate with mobility. Their low mobility may also explain why they can be very abundant at one site, but not at a similar habitat only a few kilometres away. Males fly more and are generally more active by spending most of their time locating mates. P. tithonus is a protandrous species, meaning the males emerge before the females. As a result, females usually only mate once, so they have more time available for resting, nectar feeding, host plant selection, and oviposition. Weather influences Weather has been found to have a significant influence on population size. Warm, dry summers tend to result in the biggest increase in gatekeeper population. This weather trend may explain why P. tithonus numbers have been low in northern Britain because of the cooler summers and that range expansion has resulted from climate change. Weather as a cause for changes in relative abundance has been supported in other ways, as well. Changes have also been synchronous between species including P. tithonus, with weather being a potential explanation. Based on these findings on the impact of climate, their abundance is expected to become 50% greater by 2080 given a large climate change. Reproduction One generation of gatekeeper butterflies occurs each year, with adults emerging in July and peaking in early August, and only a few adults remain at the end of the month. No specific courtship ritual is known, but the male scent spots most likely play