Do I need a safari guide in Udawalawe National Park?

Yes. The Department of Wildlife Conservation lists permit rules for national parks. One rule says each visitor must stay with an officer picked by the park office during the whole visit. This is not the same as paying for an extra private naturalist.

The officer or tracker has to ride in the vehicle that is allowed under the permit terms. Your safari operator can arrange these steps for you. You may also choose to hire a specialist who can speak English for extra talks on wildlife or for bird spotting, but that part costs extra in some cases.