The marbled underside wings are a superb example of disruptive patterning, enabling the butterfly to blend perfectly into a variety of different environments. The butterfly spends long periods at rest, and is equally well concealed when resting on tree trunks, bare earth, shingle or rocks.

When disturbed, Graylings take flight instantly, twisting and looping rapidly, just above the ground, before re-settling nearby on bare earth or on a tree trunk or fallen branch. When settling at ground level they usually rest on a pale object such as a stone or a piece of dry wood.

Upon landing they snap their wings shut, but raise the forewings so that the eyespot near the apex is visible. This way, any bird which spots where they have landed, and attacks, is likely to aim at the eyespot rather than at the body of the butterfly. Once the Grayling feels safe, it lowers the forewing to hide the eyespot behind the hindwing.

In cool conditions the butterflies tilt over to present the maximum area of wing surface to the sun, which quickly raises their body temperature. This enables them to maintain high energy levels, and remain alert at all times, instantly ready to fly up and intercept potential mates. In hot conditions they tilt their wings in the opposite direction to avoid over-heating, by minimising the amount of sunlight hitting the wings. This form of thermoregulation is commonly known as tilt-basking.

Favourite nectar sources include bell heather and cross leaved heath. Graylings often settle head-downwards when nectaring at these plants, enabling them to reach more easily into the drooping flowers with their proboscises. When feeding at other flowers such as marjoram, hemp agrimony, valerian or bramble they settle conventionally. The butterflies also commonly imbibe sap from pine trunks at heathland sites, and from ash trunks at calcareous habitats.

Graylings do not normally open their wings when settled, but copulated females will do so briefly when approached by a second intruding male, or by an intruding human. At such times the wings are held half open or fully open for 3 or 4 seconds, displaying the richly coloured upperside and prominent ocelli. I have observed this on several occasions and drawn the conclusion that this reaction probably functions to startle or deter avian and reptilian predators.

Normally the butterflies rest at ground level, but at some sites they prefer to settle on tree trunks, and at sites in northern and western England they habitually settle on dry-stone walls. In July 2007 at Wareham Heath I found a male settled on a log. Every time I approached, it flew up, then circled around me and resettled on the same log. Despite this apparent territorial behaviour, Graylings do not normally appear to actively defend their "territories" against other males, but simply use them as perches from which to intercept passing females.

Observations at Arnside Knott in July 2009 showed males often share their territories, e.g. I found one small patch of scree on which 5 males were settled. However, other observation contradict this - on 2 other occasions I watched solitary males at rest, neither of which were wary, allowing me to approach very closely for photography. On both occasions while I was crouched in front of the insect another Grayling flew by, triggering the settled male to dart up instantly and intercept it. A battle ensued in which the pair spiralled to a height of about 2 metres, chasing each other rapidly in tight circles until the intruding male was driven off. The "owner" of the scree patch then dashed instantly back to reclaim his patch, landing right in front of me. In both instances each of the Graylings had distinctive nicks in the wings which enabled me to positively ascertain which of the pair "owned" the territory and reclaimed it.