Nanog LAN - no rDNS?

It appers to only work on the local nanog DNS servers

$ host 192.35.163.157
Host 157.163.35.192.in-addr.arpa not found: 3(NXDOMAIN)

$ host 192.35.163.157 ns1.nanog.org
Using domain server:
Name: ns1.nanog.org
Address: 192.35.164.32#53