weird traffic to 1.0.0.0 port 0/udp

I'm seeing some weird traffic to port 0/udp on 1.0.0.0. Finding anything on google is tricky.
I have tracked down this paper on Bogons though:

https://noc.sara.nl/nrg/presentations/RoN-Autumn-Meeting-2006-Bogon-IP-Addresses.pdf

Could be an interesting study :)