Overland movements by the Australian chelid, Chelodina longicollis, have been documented extensively, and their relative straightness has led observers to conclude that these turtles must have a navigational sense. We observed terrestrial migration by adult C. longicollis between a permanent fresh- water lake and an ephemeral swamp in Jervis Bay National Park, New South Wales, from January-March 1994. Migrating turtles used similar non-random paths to reach their goal; movements were exclusively diurnal and occurred only under sunny conditions. Experimental studies of the orientation mechanism showed that on sunny days turtles from 2.5 km away demonstrated highly significant directional orien- tation, but that this ability was disrupted on overcast days. Animals field-tested from a distant (23 km) population oriented randomly. Turtles acclimated to a 6 hr phase-advanced light regime demonstrated a clockwise shift in their angle of orientation which was not significantly different from the expected 90?, thus implicating a biological clock component in their sun-compass orientation. Open field vs. arena (no view of horizon) trials suggest the probable use of terrestrial landmarks in navigation. Olfactory cues may play an important role in terrestrial orientation because animals tested in a Y-tank showed highly sig- nificant directional preference when swamp mud and debris were used in one of the arms.
An extensive survey was conducted on Bowen Island, Jervis Bay National Park, to locate and describe the breeding sites of Litoria aurea. Five small potentially suitable wetlands were located from aerial photographs and systematic foot-based traverses of the island. Opportunistic monitoring of these sites was undertaken during the period early November 1995 to late January 1996. Low numbers of males were heard calling at three of the five sites, but no indication of successful breeding was recorded. All wetlands on the island were found to be naturally occurring and none contained fish. A preliminary description of the wetlands and observations on the seasonal extent of calling is presented. Because the island is effectively buffered from nearby mainland populations of L. aurea, the island population should be given a priority for conservation, and appropriate monitoring and management conducted to ensure its long-term survival.
The New South Wales population of the Mountain Pygmy-possum Burramys parvus was estimated at 500 adults in 8 km2 of boulder-heath habitat during surveys in the 1980's. In 1989, this estimate was increased to 1312 adults based on further surveys in four of the identified habitat patches. However, further research indicated that population density varied greatly between habitat patches and that the original extent of habitat and the revised population estimate had been overestimated. Because of the high degree of uncertainty regarding the total population size of B. parvus in New South Wales and the relative value of each habitat patch, including those in ski resorts, it was necessary to re-evaluate these estimates. Results based on data collected between 1996 and 2001 indicated an adult population of around 613±92 in 1.85 km2 of boulderfield habitat. This population was distributed in scattered colonies within a modelled bioclimatic range of 444 km2 of suitable climate, based on modelling of the then known...
'/%3e%3c/defs%3e%3cpath fill='%23012169' d='M0 0h10080v5040H0z'/%3e%3cpath stroke='%23fff' stroke-width='.6' d='m0 0 6 3m0-3L0 3' clip-path='url(%23b)' transform='scale(840)'/%3e%3cpath stroke='%23e4002b' stroke-width='.4' d='m0 0 6 3m0-3L0 3' clip-path='url(%23c)' transform='scale(840)'/%3e%3cpath stroke='%23fff' stroke-width='840' d='M2520 0v2520M0 1260h5040'/%3e%3cpath stroke='%23e4002b' stroke-width='504' d='M2520 0v2520M0 1260h5040'/%3e%3cg fill='%23fff'%3e%3cuse xlink:href='%23d' x='2520' y='3780'/%3e%3cuse xlink:href='%23a' x='7560' y='4200'/%3e%3cuse xlink:href='%23a' x='6300' y='2205'/%3e%3cuse xlink:href='%23a' x='7560' y='840'/%3e%3cuse xlink:href='%23a' x='8680' y='1869'/%3e%3cuse xlink:href='%23e' x='8064' y='2730'/%3e%3c/g%3e%3c/svg%3e)
'%3e%3cpath fill='%23012169' d='M0 0v30h60V0z'/%3e%3cpath stroke='%23fff' stroke-width='6' d='m0 0 60 30m0-30L0 30'/%3e%3cpath stroke='%23C8102E' stroke-width='4' d='m0 0 60 30m0-30L0 30' clip-path='url(%23b)'/%3e%3cpath stroke='%23fff' stroke-width='10' d='M30 0v30M0 15h60'/%3e%3cpath stroke='%23C8102E' stroke-width='6' d='M30 0v30M0 15h60'/%3e%3c/g%3e%3c/svg%3e)
