FWIW, the most common problem I've seen when this happens is that someone's left a meta robots "noindex" tag on the page template during development and forgotten to remove it. Worth checking. You would be surprised how often this occurs.
You might also want to check your DNS setup, and check with your registrar and host that your site is functioning. A mistake in robots.txt could affect how the site is seen on all engines.
Another possibility, you don't quite describe what might be involved in this...
Moved one month ago from one site (301) to anothe
Any chance this was an old domain, perhaps an exisiting site, repurposed to take avantage of existing links? If so, there a lot of possibilities, none of them really good...
- possibly, the old domain had been burned so badly that all of the search engines were in agreement...
- also, possibly, the number of backlinks doesn't mean as much as the quality. 100+ can be a lot of backlinks, or not many at all, depending on what they are. Have you run a backlink checker on those inbound links, and looked at some of the linking sites?
I wouldn't know how to account for various search engines having similar reactions to the situation, except to say that I increasingly see Google and Bing reacting similarly to inbound links from throw-away domains. Additionally, DuckDuckGo is actually a meta search engine, relying on API data from other engines, which in turn rely on each other, so it's not as independent. as you might at first believe... albeit the privacy it affords is independent.
