tcpdump for 'disassoc' not supported

[ofthecentury]

I am getting wireless disassociation attacks.
I wanted to look at the packets via:
`tcpdump -nettt -I -i athn0 -s 256
type mgt subtype disassoc`
but I get an error:
"tcpdump: type not supported on linktype 0x1"
Should work according to man tcpdump.