Readers' observations on nature.
Early in May I discovered a dead hedgehog in my garden, in a curled, relaxed position. It appeared unharmed and asleep, but it was dead. Could it have been poisoned? Kilian Keyes, Waterfall, Co Cork
Your hedgehog may have returned to hibernation because of the very cold weather in April when it could seem dead. But it may have died during such a temporary hibernation because it had exhausted its fat and had not enough time between hibernations to replenish it.
I was walking in the rain across the sodden football fields in Bushy Park, Dublin, when I spotted a solitary heron standing in the centre of one of the empty pitches picking earthworms from the wet ground as they surfaced. John Riordan, Terenure, Dublin 6W
I was walking along the cliffs of Tory at the beginning of May and disturbed a colony of Sandwich terns. Three or four followed me for a distance behaving in an aggressive manner swooping low and squawking noisily. C Henry, Cork
You were too near their nesting site.