Pattern analysis of Scleropyll trees aggregated to different degrees

1970 ◽  
Vol 18 (2) ◽  
pp. 237
Author(s):  
WE Westman ◽  
DJ Anderson

Pattern analysis data are presented for a number of tree species populations sampled from two sites located in dry sclerophyll forest within the Ku-ring-gai Chase park of New South Wales. The distributions proved to be predominantly contagious or random, with regularity occurring only occasionally. Observed variations in the degree of aggregation exhibited by a species were taken into account in interpreting pattern analysis curves. The relation of pattern analysis data to sample quadrat data fitted to known mathematical models is extremely variable, and it is shown that pattern at block sizes other than the one under consideration may suppress the appearance of deviations from randomness at block sizes which do show contagion when sampled with randomly placed quadrats. The possible origins of contagious distributions in eucalypt forest are briefly discussed.

2016 ◽  
Vol 64 (2) ◽  
pp. 171 ◽  
Author(s):  
R. J. Turner ◽  
Peter Smith

Mistletoe proliferation has contributed to eucalypt decline in rural lands in south-eastern Australia, but has seldom been recorded within forests. We report here on mistletoes increasing deep inside extensive eucalypt forest near Eden. Mistletoes (chiefly Amyema pendula (Sieber ex Spreng.) Tiegh., some Muellerina eucalyptoides (DC.) Barlow) were counted in 180 plots in various logging and burning treatments within a long-term experimental area. In 141.4 ha, there were 516 mistletoes in 1990–1991, and 1478 mistletoes in 2004–2006. The number of trees with mistletoes increased (doubling in logged coupes and almost tripling in unlogged coupes), and the number of mistletoes per tree increased (by ~30%). However, mistletoe prevalence remained low in 2004–2006 (2.7% of trees in logged coupes and 3.7% in unlogged coupes). Intensive logging limited the increase in mistletoe-bearing trees, probably because there were fewer trees available in logged coupes, but had no significant effect on the increase in mistletoes per tree. Low-intensity prescribed burns had no significant effect on mistletoe numbers, even with a high frequency of burning, probably because of their low scorch heights. We suggest that the observed increase in mistletoes in this forest, rather than indicating an ecological imbalance, is part of a natural cycle of boom and bust, with populations crashing in severe wildfires.


1976 ◽  
Vol 27 (4) ◽  
pp. 551 ◽  
Author(s):  
RDJ Tilzey

The fish fauna of all major streams within the Lake Eucumbene catchment in south-eastern New South Wales was sampled by electrofishing or poisoning with rotenone. Galaxias coxii was found in only four, and G. olidus in only one other of the 27 streams sampled whereas the introduced salmonids (Salmo trutta or S. gairdneri, or both) occurred in all but the stream containing G. olidus. Values for galaxiid biomass were low in comparison with those for trout where both occurred together. Sampling in 1971 and 1974 in the one stream observed in 1971 to contain only G. olidus spanned an invasion by S. gairdneri and by 1974 the galaxiid species had completely disappeared below a natural barrier to trout, but above this barrier the biomass and population structure of G. olidus had not changed greatly compared to the 1971 values. This indicated that the presence of S. gairdneri was the sole environmental factor causing galaxiid disappearance below the barrier. Historical data for the catchment area suggested that the introduction and subsequent success of trout are primarily responsible for the present, much fragmented galaxiid distribution.


1986 ◽  
Vol 13 (2) ◽  
pp. 203 ◽  
Author(s):  
RH Harden ◽  
RJ Muir ◽  
DR Milledge

The effects of varying transect width and census duration on the number of birds counted, the density estimate, number of species detected and the percentage of unidentified birds were examined in rainforest and wet sclerophyll forest at Mount Nardi in northern New South Wales. The nine combinations of three strip widths (40, 60 and 80 m) and three durations of census (24, 18 and 12 min) were compared in 200-m-long transects in each forest. The census of birds was more sensitive to changes in census duration than in strip width, and the effects were greater in the rainforest than the wet sclerophyll forest. Both the precision of the density estimates and the number of species detected were highest for the narrowest strips censused for the longest time. The bias of the density estimate varied with the treatments both within and between forests, and thus the strip transect could not be used to compare them. We suggest that variation in bias between sites may be a problem common to all transect counts of birds.


Two specimens of this curious animal, lately brought from New South Wales, the one male and the other female, and both full grown and perfect, having been submitted to the inspection and close examination of Mr. Home, by Sir Joseph Banks, this gentle­man has availed himself of the favourable opportunity to draw up the full account of all that is hitherto known concerning its habits, of its external appearance, and internal structure now before us. The animal has hitherto been only found in the fresh-water lakes, in the interior parts of the above-mentioned country. It does not swim upon the surface of the water, but comes up occasionally to breathe. It chiefly inhabits the banks of these lakes, and is supposed to feed in the muddy places which surround them; but the particular kind of food on which it subsists is not known.


1986 ◽  
Vol 34 (6) ◽  
pp. 675 ◽  
Author(s):  
TC Chambers ◽  
MA Regan

Two well preserved axes discovered in the Late Devonian Mudstones at Barraba, New South Wales, Australia, have an anatomy resembling that of Polyxylon elegans described in 1939 by Read and Campbell from the Late Devonian New Albany Shale of Indiana, U.S.A. in the northern hemisphere. We have erected a new species, Polyxylon australe, for these larger axes from the southern hemisphere. From our study of the anatomy of both the Australian and American axes we agree with Leclercq, who in 1970 grouped Polyxylon with the Cladoxylopsida. However, in Polyxylon australe the protoxylem appears to be exarch at the tips of the xylem arms while in most other members of the Cladoxylopsida the protoxylem seems to be confined to a peripheral loop in each radially aligned vascular segment. The occurrence of two species of the one genus with similar anatomical structures, geographically at great distance from one another, raises some interesting questions of Late Devonian phytogeography.


2014 ◽  
Vol 36 (1) ◽  
pp. 29 ◽  
Author(s):  
Rebecca L. Drury ◽  
Fritz Geiser

We quantified activity patterns, foraging times and roost selection in the eastern blossom-bat (Syconycteris australis) (body mass 17.6 g) in coastal northern New South Wales in winter using radio-telemetry. Bats roosted either in rainforest near their foraging site of flowering coast banksia (Banksia integrifolia) and commuted only 0.3 ± 0.1 km (n = 8), whereas others roosted 2.0 ± 0.2 km (n = 4) away in wet sclerophyll forest. Most bats roosted in rainforest foliage, but in the wet sclerophyll forest cabbage palm leaves (Livistonia australis) were preferred roosts, which likely reflects behavioural thermoregulation by bats. Foraging commenced 44 ± 22 min after sunset in rainforest-roosting bats, whereas bats that roosted further away and likely flew over canopies/open ground to reach their foraging site left later, especially a female roosting with her likely young (~4 h after sunset). Bats returned to their roosts 64 ± 12 min before sunrise. Our study shows that S. australis is capable of commuting considerable distances between appropriate roost and foraging sites when nectar is abundant. Bats appear to vary foraging times appropriately to minimise exposure to predators and to undertake parental care.


1987 ◽  
Vol 14 (3) ◽  
pp. 263 ◽  
Author(s):  
D. Lunney

Seven species of possums and gliders were found during a survey in logged coastal forests near Bega, New South Wales. A study of the preferences for the various tree species showed that both commercial and non-commercial species must be retained to support the full range of possum and glider species. Spotlight searches were carried out in 6 adjacent felling areas each autumn from 1981 to 1983. Four species (Petaurus breviceps, P. australis, Petauroides volans and Pseudocheirus peregrinus) were seen frequently enough to determine their habitat preferences. There were significantly fewer possums and gliders in logged areas, with a greater effect on some species, e.g. P. volans, than others, e.g. P. breviceps. Fire rendered the logged areas even less habitable, and drought compounded the effects of logging and fire by further reducing numbers. Deep unlogged gullies were found to be crucial refuges from logging, fire and drought. The primary conclusions are that the current logging operation is causing a significant reduction in numbers, and that gullies need to be redefined to include all drainage lines and to remain unlogged.


1983 ◽  
Vol 31 (6) ◽  
pp. 881 ◽  
Author(s):  
TR Grant ◽  
M Griffiths ◽  
RMC Leckie

Female platypuses captured in waters of eastern New South Wales were found to be lactating between the months of October and March. Lactating females were most numerous in December, accounting for 64% of females captured. Non-lactating females were taken in all months, indicating that not all females breed successfully every year. There was no significant difference between the fatty acid complement of milk taken from a platypus lactating very late in the season and those of others sampled in December at the peak of the lactation season. Some evidence exists that females do not become reproductive until at least their second year of life. Some females were found lactating in consecutive years, and others lactated one year and not in the one following. Animals of over 9 years of age are known to breed. Most juveniles were captured in February, March and April, and it is suggested that the young leave the breeding burrows for the first time in late January through to March, and become independent from their mothers, who are ceasing lactation at that time.


2000 ◽  
Vol 27 (1) ◽  
pp. 1 ◽  
Author(s):  
Stephen Phillips ◽  
John Callaghan ◽  
Valerie Thompson

An assessment of the tree species preferences of koalas inhabiting forest and woodland communities growing on Quaternary deposits in the Port Stephens area, New South Wales, was undertaken between November 1994 and March 1996. Using a plot-based methodology, 3847 trees were sampled, comprising 15 Eucalyptus species and 17 species of non-eucalypt. Evidence of tree use by koalas, specifically the presence of koala faecal pellets, was recorded from beneath 10 Eucalyptus species and 9 species of non-eucalypt. Tree species preferences were determined by analyses of log- likelihood ratios derived from data based on the presence/absence of koala faecal pellets, rather than on gross counts. This approach confirmed significant variation in the levels of utilisation amongst and between different tree species, and that two in particular – swamp mahogany (E. robusta) and drooping red gum (E. parramattensis) – were most preferred. Increases in the levels of use of other tree species were also positively associated with the presence of E. robusta and/or E. parramattensis. Levels of utilisation of E. robusta and E. parramattensis did not alter significantly in response to changes in their respective densities, suggesting that the relative abundance of both was important in terms of understanding the carrying capacity of vegetation communities utilised by koalas. The results have established the success with which an enumerative approach to the interpretation of faecal pellet data can be utilised to clarify the tree species preferences of koalas. Application of the approach for habitat assessment and mapping purposes is also discussed.


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