Country diary: a nocturnal predator cuts life short

My dog slunk across the lawn, crunching guiltily. She had been sniffing around the garden pond and found something tasty. I shut her in the house and went to investigate.

Hidden beneath a clump of pendulous sedge, I discovered an untidy, scrabbled-together heap of broken reeds containing nine large eggs. Five were pale blue, three were greeny-brown and one was an indeterminate light colour.

They were duck eggs, from a wild mallard. The blue ones were slightly bigger and much grubbier than the rest, indicating perhaps that they were laid first and had been rolled around more.

Mallards lay once every couple of days and do not start incubating until the clutch is complete, usually at around 12 eggs. With 10 eggs in total, including the one the dog filched, the female and occasionally her mate must have been active outside my kitchen window for about two weeks. My pride in being an observant country diarist was bruised. How could I have missed them?

With the dog banned from that part of the garden, I went back later to check if the duck had returned. She was there, sitting tight, neck snaked flat, astonishingly well camouflaged. Her brown and buff-striped plumage mimicked the vegetation, only an eye stood out, unblinking orange ringed with black.

She laid one more egg and then began to brood. The drake was absent during the day but roosted near her every night, flying in at dusk, punctuating the melodious evening songs of blackbirds and robins with loud, repetitive quacks.

A week into incubation she rearranged her nest, adding feathers pulled from her breast and rags of moss. When she was away feeding, I noticed there were now only eight eggs, all blue. There had to be a nocturnal predator, possibly rats but most likely a fox.

One morning about 10 days before hatching was due, I found the duck and drake together on the water, paddling in agitated circles. The nest was scuffled out and the whole clutch gone. I think a vixen took the eggs, carrying them off to feed her cubs. The ducks flew away and have not returned.

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