Does Spawn Fishing Hurt Bass Population?

Oregon Fish and Wildlife thinks so. see (page down) to
Special Request for Crane Prairie Lake: :

http://members.tripod.com/~merilu88/a_tmbc.html

Seems like the previously voluminous but illegally introduced largemouth
bass population at Crane Prairie lake has plummeted. To fix the problem
(restore LM bass to previous huge numbers) ODF&W has requested all June
Crane Prairie tournaments to be cancelled and for the public not to bass
fish in June 07 and 08.

Does spawn bass fishing have any serious affect on bass mortality or
population degradation? Has anyone seen any research anywhere to
substantiate or repudiate ODF&W's position that no over spawn bass fishing
will increase fry survivability and restore LM bass population numbers?

Thanks.
John