Sun compass in animals internal clock to determine their heading, and that they had learnt the actual direction down to the sea on their particular beach. Lockley's experiments with Manx shearwaters ("Puffinus puffinus") showed that when released "under a clear sky" far from their nests (in Skokholm), the seabirds first oriented themselves and then "flew off in a direct line for Skokholm", making the journey rapidly. For example, one of the birds, released at Boston airport, arrived in Skokholm 12½ days later; Lockley calculated that if the birds flew for 12 hours per day, they must have travelled at 20 miles per hour, their
Trevor H. Worthy the Waitomo frog ("Leiopelma waitomoensis"). In the 1990s Worthy discovered several fossil bird species new to science, including the long-billed wren ("Dendroscansor decurvirostris") in 1991, Scarlett's shearwater ("Puffinus spelaeus") in 1991, and the Niue night heron ("Nycticorax kalavikai") in 1995. In 1991 he also described the Northland skink, a fossil skink species new to science. In 1998 Worthy excavated subfossil bones in Fiji, where he found remains of the flightless Viti Levu giant pigeon ("Natunaornis gigoura"), the Viti Levu scrubfowl ("Megapodius amissus"), the Viti Levu snipe ("Coenocorypha miratropica"), the giant Fiji ground frog ("Platymantis megabotoniviti"), and the small freshwater crocodile