My dog has started barking at night...

[WindyCommon]

I don't know why, and I'm not sure how to respond. So asking PH for advice in the usual way...

He's a show-type cocker spaniel, 2.5 yrs old. Wonderfully calm and kind - very much the perfect family dog. He's rarely left alone during the day, and is well-walked and played with. We are lucky to have a powerfully-built garden that he can run around when he wants to go outside. His life would be the envy of many dogs! Since we stopped using his crate (at about 6 months) he's slept in a luxurious Orvis sofa bed behind a gate in the passage leading to our utility room. He's always been the best of sleepers; even as a tiny puppy I think he only woke us up a handful of times. He puts himself to bed (as he always had done) at around 11pm and is normally waking up when my wife or I go downstairs between 6 and 6:30am.

Since Christmas he has started (4 times now) waking up in the night - 3am this morning - and barking/howling non-stop. I don't think he's been disturbed, or seen anything through the patio door. His barking isn't what I would identify as a warning/guarding bark, nor is it anything like his "I'm in pain please help" barks. The first couple of times I just thought "something's disturbed him - I'd better go down and see". I put him back in his bed and all was ok.

This isn't a pattern I'm prepared to bed in as normal though! Since my boys started to sleep properly - they are 9 and 11 now - I've enjoyed sleeping through again myself. Last night I talked with my wife about what we'd do if he went for a repeat performance. Our suspicion is that he's waking up and just deciding that he can summon company if he's determined enough with his barking. We concluded we'd just let him bark and not respond.

He started at 3am. After 30 minutes he'd woken up both of my kids. Not good, as today was their first day back in school. In a change of plan I went downstairs and delivered a convincing bking with no eye contact and the tap on the nose I use [rarely] when he transgresses. Dog was clearly surprised and chastened. He went back to bed and that was the end of it. This morning he was sheepish and somewhat submissive - clearly he knew that he'd been in trouble.

So...

Do dogs sometimes start to bark at night for no reason, or am I missing something? Is it age/development related?
Is being tough the right way to go with this?
What other options do I have? [we don't want him in our bedroom, he's not generally allowed upstairs]

All thoughts welcomed. Thank you in advance.

[GT03ROB]

Ours started doing the same about 6 months back. Every morning about 05:40. Finally realised it was because he picks up on the newspaper delivery man he drops off opposite. He can't see the man, the noise is imperceptible

There is probably something that is happening outside that your dog is picking up on. Could be a fox or something that he can sense.

[otolith]

If we don't put him in his crate and cover it up so he can't see out, my girlfriend's dog wakes the house up in the middle of the night going mental at foxes. He does it in the daytime too - squirrels, birds, etc, anything he sees in the garden gets barked at.