In some cases, the hedgehogs, which are protected, had ingested rat poison, and others had eaten slugs or snails poisoned with metaldehyde, a compound substance commonly found in the cheaper form of slug pellets, according to Hedgehog Rescue Dublin.
Ecologist Yvonne McCann, who has been rescuing the nocturnal creatures at Rush, Co Dublin, since 2013, said cheaper slug pellets are “lethal” to the furtive creatures.
She is urging gardeners to switch to beer traps and other natural slug and insect deterrents or to use the dearer organic pellets.
Hedgehogs who sleep during the winter are in the middle of their breeding season right now.
Dozens of small hedgehogs, some blind newborns, which have been disturbed or abandoned, are also being brought into the centre as gardening activity increases and Yvonne currently has 10 baby urchins, also known as hoglets, on her hands.
Other hedgehogs have been injured in hedge trimming or lawn mowing accidents.
Luckily, the mother hedgehogs are with the 10 juniors brought to the rescue centre in recent weeks as a result of garden clean-ups, Ms McCann said. This makes feeding and rearing them much easier as otherwise, she has to use syringes filled with milk. Already nervous creatures, in spite of their appearance, frightened hedgehog mothers will eat or abandon their young, she pointed out.
Ms McCann urges people to cover any nests they find with the material removed, or with leaves immediately and “wait 24 hours”.
There is very little awareness about hedgehog nests, she said: “We would always advise people to quickly cover the nest up and leave it alone, if possible. Taking a mother and babies into rescue is so stressful on her and they quite often reject the babies.”
Hedgehogs snuggle down a couple of centimetres under sheds and hedges and gardeners don’t spot them until it is too late. In many cases the mothers, who are extremely shy, run off and abandon the nests (the male hedgehog takes no part in rearing the young).
However, if a hedgehog is “out and about during the day” chances are it does need help, she said.
Ironically, hedgehogs are themselves useful in the garden, munching up a wide variety of slugs and other insects, along with fallen fruit — so decreasing the need for garden chemicals.
Ms McCann said hedgehogs are less common in some areas than others and foxes and badgers can be a factor. Urban areas where many gardens are walled off can also deter hedgehogs — they like to roam freely and their homes are always temporary.