The island of Tokong Burung (or sometimes called Bird Island) is accessible by boats. The journey will take about 40 minutes from either Perhentian Besar (Big Island) or Perhentian Kecil (Small Island).
Also, Tokong Burung is about 5 minutes boat ride away from Pulau Rawa. Some tour operators may bring you here, some would just stop by at Pulau Rawa for snorkeling and return back to the Perhentian Besar or Perhentian Kecil without stopping at Tokong Burung.
While the marine life itself is not as prolific, but I was amazed by the clarity of the water. Perhaps the considerable distance of Tokong Burung from everything else in the Perhentians has preserved the visibility of this snorkeling spot.
Also, one could not find any traces of broken staghorn or table corals, which normally a ubiquitous sight in places infested by fin-equipped snorkelers. The corals are definitely healthier than most snorkeling spots in Perhentian. In term of variety, Tokong Burung fares quite well. I saw various types of hard corals such as green staghorn corals, boulder corals, flat corals, table corals, sea anemones, as well as colourful christmas tree worms and a rare colony of black crinoids!
Noticeably, this snorkeling spot does not have that much fish variety, only various specie of damselfish that I could find here. Nonetheless, from overall perspective, this is a nice place to snorkel!