Low Adsense eCPM after traffic spike?

Interested in other webmaster experiences.

[dutch_dude]

I have a website which has some pretty massive spikes in visitor numbers due to its subject. (only natural search engine traffic, no spam) The spikes are mostly very short in time, sometimes as short as an hour.

I recently had such a spike and now in the following days with normal visitor numbers my eCPM is terrible. It is so low I am even considering dropping Adsense and to make my own ads for affiliate programs.

Do other webmasters with Adsense and spikes in visitor numbers have this same experience of very low eCPM when visitor numbers are back to normal? Trying to determine if it is coincidence or a pattern.

[webnoob]

traffic spike for an hour? sounds like spiders to me.

[dutch_dude]

No it's natural traffic. The site's forum is loaded with new posts too in such a spike.

[WallyWorld]

My EPC has been dropping every day since hitting recent highs just after the Google changes to AdWords earlier this month. Now the EPC is the lowest I've seen it in several months. I think it is because advertisers are adjusting their campaigns to the new AdWords model.

I know I've dropped some of my AdWords campaigns and lowered some PPC amounts because of poor performance since the change. Maybe it's just August but we'll see.

[dutch_dude]

WallyWorld:

Thanks, sounds like a logical explanation. Hoping it will get better. I am not looking forward to weeks of work to figure out and tweak affiliate programs ;)