A team of researchers spent a month analysing reported animal sightings in order to collate a list of the 20 most elusive indigenous species.
More than 96 per cent of those surveyed said they had never spotted a nightjar – a nocturnal camouflaged bird, of which there are just 4,606 pairs in Britain.
Pine martens, which spend the majority of their time in the treetops, and number just over 3,000 UK-wide, are equally as elusive. The golden eagle, which has only been seen by 11 per cent of people across Britain, is one of the rarest species – totalling just 442.
The Natural Curiosities report found that more than half of the UK population have never seen an adder, dormouse or badger in their natural habitat.
Around a quarter had not seen common animals in the wild such as a hedgehog, fox or frog.
Dr Toni Bunnell, who led the team, said: “Only the very diligent amongst us will succeed in spotting any of the top ten in their natural habitat, but it is well worth the effort.”
Stoats and weasels also appeared in the top five most elusive animals, even though they number 462,000 and 450,000 respectively.
Broadcaster and naturalist Sir David Attenborough, who is to present new TV show David Attenborough’s Natural Curiosities, which inspired the report, added: “I’ve been lucky enough to see most of the animals listed in the wild except for the pine marten which are exceptionally hard to spot as they live up in the tree tops.
“The fact a quarter of British adults have never seen a hedgehog suggests we are witnessing dwindling numbers.”