You're not alone Craig. I get it myself sometimes though perhaps not quite as badly as you. It sometimes takes me a few seconds after hearing the call to delve the depths of my memory to identify it. Especially if it's a bird I've not heard for a while like newly arrived summer migrants.
I'm probably not the worlds greatest when it comes to birdcalls and song. I'm not completely rubbish though, and I can probably identify 95% plus of UK common birds by sound. But sometimes, like today I have a complete mind warp. Walking round the edge of Walker fold I kept hearing a bird call. I knew the call. I can hear it now and know I've heard it hundreds of times before. I also know, I know what makes that call.... BUT I CANT REMEMBER!!!!!! What is even more annoying is next time I hear it I'll just think 'oh there's a .....whatever' and not give it a second thought.
Please tell me I'm not alone with this affliction!
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No one on their death bed ever said they wished they'd spent more time at work. http://bitsnbirds.blogspot.co.uk