Evidence for Adaptive Variation in the Orientation of Amitermes (Isoptera, Termitinae) Mounds From Northern Australia

1991 ◽  
Vol 39 (5) ◽  
pp. 569 ◽  
Author(s):  
P Jacklyn
Keyword(s):  
Northern Territory ◽  
Northern Australia ◽  
Termite Mounds ◽  
The West ◽  
Adaptive Value ◽  
Comprehensive Survey ◽  
Cape York ◽  
The Mean ◽  
Amitermes Meridionalis ◽  
Mound Sites

Amitermes meridionalis and Amitermes laurensis construct meridional termite mounds that are endemic to northern Australia. The first comprehensive survey of the orientation of these mounds, involving 68 mound sites across northern Australia, is described. The mean mound orientations of most coastal A. meridonalis sites were significantly (P < 0.05) to the west of those of most inland A. meridionalis sites. The mean orientations of most A. laurensis sites in Cape York Peninsula were significantly (P < 0.05) to the west of those of most A. meridonalis and A. laurensis sites in the Northern Territory. Most shaded mound sites had significantly (P < 0.05) greater variance in mound orientation than nearby open sites. It is suggested that the geographic variation in mound orientation is an adaptive response to differences in local environmental conditions and that such variation provides the key to explaining the adaptive value of meridional orientation.

Observations of the 'Critically Endangered' bare-rumped sheathtail bat Saccolaimus saccolaimus Temminck (Chiroptera: Emballonuridae) on Cape York Peninsula, Queensland.

2001 ◽  
Vol 23 (2) ◽  
pp. 185 ◽  
Author(s):  
S Murphy
Keyword(s):  
Papua New Guinea ◽  
Solomon Islands ◽  
Conservation Status ◽  
New Guinea ◽  
Fire Regimes ◽  
Wide Distribution ◽  
Northern Territory ◽  
Critically Endangered ◽  
Northern Australia ◽  
Cape York

THE bare-rumped sheathtailed bat Saccolaimus saccolaimus is a poorly understood species that has a wide distribution covering parts of India, Sri Lanka, Thailand, Myanmar, Malaya, Indonesia, New Guinea, the Solomon Islands and Northern Australia (Bonaccorso 1998). First collected in Australia by De Vis near Cardwell, the current known distribution in Queensland (Qld) extends from Bowen to Cooktown with one isolated specimen collected near Coen on Cape York Peninsula (Hall 1995; Duncan et al. 1999). It has also been recorded in the Alligator River area in the Northern Territory (McKean et al. 1981). The conservation status of S. saccolaimus in Qld has recently been defined as ?Critically Endangered?, and the species has not been recorded anywhere in Australia for at least 18 years (Duncan et al. 1999; Menkhorst and Knight 2001). The likely reasons for the apparent decline are unclear, but may involve land-clearing and changed fire regimes in the coastal zone where it is thought to occur (Duncan et al. 1999). In contrast, Bonaccorso (1998) considers S. saccolaimus to be secure, albeit also poorly known in Papua New Guinea.

Three new species of the sucking louse genus Hoplopleura (Phthiraptera: Anoplura: Hoplopleuridae) from rodents (Mammalia: Rodentia: Muridae) in northern Australia

Zootaxa ◽  
2017 ◽  
Vol 4247 (1) ◽  
pp. 31 ◽  
Author(s):  
HAYLEE J. WEAVER
Keyword(s):  
New Species ◽  
Northern Territory ◽  
Rodent Species ◽  
Northern Australia ◽  
Cape York ◽  
Louse Species ◽  
Three New Species

Three new species of the rodent louse genus Hoplopleura (Anoplura: Hoplopleuridae) are described and illustrated from Australia: H. melomydis new species from Melomys burtoni (Muridae: Hydromyini, grassland melomys) and M. capensis (Muridae: Hydromyini, Cape York melomys) from Queensland; H. notomydis new species and H. setosa new species from Notomys alexis (Muridae: Hydromyini, spinifex hopping mouse) from the Northern Territory. These new louse species are the first lice recorded from each of the three host rodent species. 

Distribution and Status of the Northern nailtail wallaby, Onychogalea unguifera (Gould, 1841)

1991 ◽  
Vol 18 (6) ◽  
pp. 655 ◽  
Author(s):  
S Ingleby
Keyword(s):  
Geographical Distribution ◽  
National Parks ◽  
Western Australia ◽  
Northern Territory ◽  
Northern Australia ◽  
The West ◽  
Field Surveys ◽  
Using Data

Past and present distributions of 0. unguifera were compared using data from museums, explorers' records and field surveys conducted during 1986-88. There is little evidence of a decline in geographical distribution or abundance of this species during the last century, although numbers may have declined locally in parts of the West Kimberley in Western Australia. At present 0. unguifera is moderately common between latitudes 16� and 19�S. in the Northern Territory and western Queensland and in the East Kimberley region of Western Australia. It is uncommon towards the northern and southern limits of its range in each State. These limits correspond to latitudes 12�-14�S. and 20�-22�S. respectively. 0. unguifera appears to be under no immediate threat. However, its preferred habitats are poorly represented in National Parks and other conservation reserves throughout northern Australia, and this situation should be remedied.

scholarly journals Late Holocene Aboriginal shellfish production strategies in northern Australia: Insights from Prunung (Red Beach), Weipa, Cape York Peninsula

2015 ◽  
Vol 18 ◽  
Author(s):  
Michael Morrison
Keyword(s):  
Late Holocene ◽  
Western Cape ◽  
Northern Australia ◽  
The North ◽  
Mound Construction ◽  
Shell Mounds ◽  
Production Strategies ◽  
Cape York ◽  
Mound Sites

<span>Recent investigations into the role of shell mounds in late Holocene Aboriginal economies in northern Australia have focussed on one of the key constituents in mound sites: the intertidal bivalve, </span><em>Tegillarca granosa</em><span> (formerly </span><em>Anadara granosa</em><span>). Various researchers have suggested that shell mounds were constructed during production activities that were predominantly oriented towards exploitation of estuarine or marine ecosystems, with other resources being of secondary or supplementary importance during these times. Proponents of this model concede that it requires ongoing evaluation in relation to new quantitative data on mound composition, stratigraphy and chronology from shell mound sites across a range of different environmental contexts. At Weipa, in western Cape York Peninsula, recent research has been oriented toward collecting new data necessary for investigating the role of mound sites and the production strategies associated with their formation. In this paper, the results of excavations and analysis of a series of shell mounds at Prunung (Red Beach), to the north of Weipa, are presented. These results support the view that mound construction took place in the context of production activities strategically oriented towards intertidal flats, rather than broadly-based foraging within local site catchments, or a more generalised ‘estuarine’ orientation.</span>

New species of Drymopsalta Heath Cicadas (Cicadidae: Cicadettinae: Cicadettini) from Queensland and Northern Territory, Australia, with overview of genus

Zootaxa ◽  
2013 ◽  
Vol 3620 (1) ◽  
pp. 1-42
Author(s):  
A. EWART ◽  
L. W. POPPLE
Keyword(s):  
New Species ◽  
High Frequency ◽  
Similar Pattern ◽  
National Park ◽  
Northern Territory ◽  
Allopatric Species ◽  
Temporal Structures ◽  
Cape York ◽  
Three New Species ◽  
Tree Foliage

Three new species are described in the genus Drymopsalta Ewart, previously known only from D. crepitum Ewart and D. daemeli Distant. The three new species occur in Southern Queensland and Northern Territory. D. wallumi sp. nov. occurs along coastal S.E. Queensland, whereas D. hobsoni sp. nov. is restricted to the Bringalily State Forest, near Inglewood, southern inland Queensland. D. acrotela sp. nov. is found in the Litchfield National Park and other locations near Jabaluka, Cahills Crossing, E. Alligator River and Nourlangie, all across the northern Northern Territory. D. crepitum occurs on the Cape York Peninsular extending into the southern Gulf, while D. daemeli occurs in two localised regions in central coastal N.S.W. Each of the species inhabits heath vegetation, often spilling-over into adjacent tree foliage. The species of Drymopsalta are small and inconspicuous cicadas (<15 mm body length) with relatively high frequency songs (~15 to 22 kHz). The temporal structures of the normal calling songs follow a similar pattern in each species, consisting of the emission of short chirps (comprising 2–16 ticks). Between the chirps are emitted one (D. wallumi, D. hobsoni, D. acrotela), two (D. daemeli) or 1–9 (D. crepitum) intervening single ticks. The species can be distinguished by the timing and the number of these single ticks relative to the adjacent chirps with the notable exception of D. hobsoni and D. acrotela. The calling songs of these two allopatric species are indistinguishable, an unusual feature in Australian cicadas. Two additional song variants are described, a more unstructured chirping song without intervening single ticks observed in each of the species except D. crepitum, and periodic extended buzzing echemes emitted within the calling songs (excepting the D. wallumi song).

The Role of Intraseasonal Variability in the Nature of Asian Monsoon Precipitation

2007 ◽  
Vol 20 (17) ◽  
pp. 4402-4424 ◽  
Author(s):  
Carlos D. Hoyos ◽  
Peter J. Webster
Keyword(s):  
Indian Ocean ◽  
Time Scales ◽  
Temporal Variability ◽  
Asian Monsoon ◽  
Monsoon Rainfall ◽  
Mountain Range ◽  
Monsoon Precipitation ◽  
The West ◽  
The Mean ◽  
Rainfall Estimates

Abstract The structure of the mean precipitation of the south Asian monsoon is spatially complex. Embedded in a broad precipitation maximum extending eastward from 70°E to the northwest tropical Pacific Ocean are strong local maxima to the west of the Western Ghats mountain range of India, in Cambodia extending into the eastern China Sea, and over the eastern tropical Indian Ocean and the Bay of Bengal (BoB), where the strongest large-scale global maximum in precipitation is located. In general, the maximum precipitation occurs over the oceans and not over the land regions. Distinct temporal variability also exists with time scales ranging from days to decades. Neither the spatial nor temporal variability of the monsoon can be explained simply as the response to the cross-equatorial pressure gradient force between the continental regions of Asia and the oceans of the Southern Hemisphere, as suggested in classical descriptions of the monsoon. Monthly (1979–2005) and daily (1997–present) rainfall estimates from the Global Precipitation Climatology Project (GPCP), 3-hourly (1998–present) rainfall estimates from the Tropical Rainfall Measuring Mission (TRMM) microwave imager (TMI) estimates of sea surface temperature (SST), reanalysis products, and satellite-determined outgoing longwave radiation (OLR) data were used as the basis of a detailed diagnostic study to explore the physical basis of the spatial and temporal nature of monsoon precipitation. Propagation characteristics of the monsoon intraseasonal oscillations (MISOs) and biweekly signals from the South China Sea, coupled with local and regional effects of orography and land–atmosphere feedbacks are found to modulate and determine the locations of the mean precipitation patterns. Long-term variability is found to be associated with remote climate forcing from phenomena such as El Niño–Southern Oscillation (ENSO), but with an impact that changes interdecadally, producing incoherent responses of regional rainfall. A proportion of the interannual modulation of monsoon rainfall is found to be the direct result of the cumulative effect of rainfall variability on intraseasonal (25–80 day) time scales over the Indian Ocean. MISOs are shown to be the main modulator of weather events and encompass most synoptic activity. Composite analysis shows that the cyclonic system associated with the northward propagation of a MISO event from the equatorial Indian Ocean tends to drive moist air toward the Burma mountain range and, in so doing, enhances rainfall considerably in the northeast corner of the bay, explaining much of the observed summer maximum oriented parallel to the mountains. Similar interplay occurs to the west of the Ghats. While orography does not seem to play a defining role in MISO evolution in any part of the basin, it directly influences the cumulative MISO-associated rainfall, thus defining the observed mean seasonal pattern. This is an important conclusion since it suggests that in order for the climate models to reproduce the observed seasonal monsoon rainfall structure, MISO activity needs to be well simulated and sharp mountain ranges well represented.

Investigation into the diet of the central rock-rat (Zyzomys pedunculatus)

2003 ◽  
Vol 30 (5) ◽  
pp. 513 ◽  
Author(s):  
Theresa J. Nano ◽  
Cate M. Smith ◽  
Elizabeth Jefferys
Keyword(s):  
Sample Size ◽  
Conservation Status ◽  
Microscopic Analysis ◽  
Faecal Pellet ◽  
Northern Territory ◽  
The West ◽  
Major Food ◽  
Seasonal Shift ◽  
Leaf Consumption

The diet of the rare central rock-rat, Zyzomys pedunculatus, was assessed by microscopic analysis of 18 faecal pellet samples collected from four different sites in the west MacDonnell Ranges in the Northern Territory. Samples were collected from the four sites in summer (n = 13), one site in winter (n = 3), and two sites in spring (n = 2). Four major food categories were observed in the samples: seed, leaf, stem and insect. Seed was by far the most dominant food in the overall diet of Z. pedunculatus, making up 72% of identifiable particles, leaf was secondary (21%), while stem and insects contributed only 3% and 4% respectively. Although the sample size was small, no major seasonal shift between seed and invertebrate dominance was evident. Seed dominated the diet in both summer and winter, though winter seed consumption was lower (78% v. 58%). The level of seed consumption in the two spring samples was highly divergent (38% v. 93%), stressing the need for more samples to be collected from dry periods. Lowered rates of seed consumption during winter and in one of the spring samples were accompanied by increases in leaf consumption. Insect consumption remained low across all sampled seasons, suggesting that this species is not an omnivore. Rather, the dominance of seed in the diet suggests that Z. pedunculatus is primarily a granivore, a finding that has implications for the conservation status and management of this little-known species.

scholarly journals La Niña–like Mean-State Response to Global Warming and Potential Oceanic Roles

2017 ◽  
Vol 30 (11) ◽  
pp. 4207-4225 ◽  
Author(s):  
Tsubasa Kohyama ◽  
Dennis L. Hartmann ◽  
David S. Battisti
Keyword(s):  
Global Warming ◽  
Southern Oscillation ◽  
Forced Response ◽  
Equatorial Pacific ◽  
La Niña ◽  
The West ◽  
La Nina ◽  
The Mean ◽  
Mean State ◽  
Sst Gradient

Abstract The majority of the models that participated in phase 5 of the Coupled Model Intercomparison Project global warming experiments warm faster in the eastern equatorial Pacific Ocean than in the west. GFDL-ESM2M is an exception among the state-of-the-art global climate models in that the equatorial Pacific sea surface temperature (SST) in the west warms faster than in the east, and the Walker circulation strengthens in response to warming. This study shows that this “La Niña–like” trend simulated by GFDL-ESM2M could be a physically consistent response to warming, and that the forced response could have been detectable since the late twentieth century. Two additional models are examined: GFDL-ESM2G, which differs from GFDL-ESM2M only in the oceanic components, warms without a clear zonal SST gradient; and HadGEM2-CC exhibits a warming pattern that resembles the multimodel mean. A fundamental observed constraint between the amplitude of El Niño–Southern Oscillation (ENSO) and the mean-state zonal SST gradient is reproduced well by GFDL-ESM2M but not by the other two models, which display substantially weaker ENSO nonlinearity than is observed. Under this constraint, the weakening nonlinear ENSO amplitude in GFDL-ESM2M rectifies the mean state to be La Niña–like. GFDL-ESM2M exhibits more realistic equatorial thermal stratification than GFDL-ESM2G, which appears to be the most important difference for the ENSO nonlinearity. On longer time scales, the weaker polar amplification in GFDL-ESM2M may also explain the origin of the colder equatorial upwelling water, which could in turn weaken the ENSO amplitude.

scholarly journals The Characteristics of West Season Wind and Wave as well as Their Impacts on Ferry Cruise in The Kalianget-Kangean Cruise Route, Madura, Indonesia

2021 ◽  
Vol 29 (3) ◽  
Author(s):  
Viv Djanat Prasita ◽  
Lukman Aulia Zati ◽  
Supriyatno Widagdo
Keyword(s):  
Wind Speed ◽  
Wave Height ◽  
The West ◽  
Wind Speeds ◽  
Wave Patterns ◽  
Time Stamps ◽  
The Mean ◽  
Two Peaks ◽  
The Impact ◽  
Descriptive Statistical Analysis

The wind and wave conditions in the waters of the Kalianget-Kangean cruise route in the west season are relatively high so that these winds and waves can have a dangerous impact on that cruise route. The aim of this research was to analyze the characteristics of wind speed and wave height over a 10 year period (2008-2017), as well as to evaluate the weekly patterns for three months (December 2017-February 2018). These time stamps represent the west season in waters at Kalianget-Kangean route, and to identify the impact of winds and wave on this path. The method used in this research is descriptive statistical analysis to obtain the mean and maximum values ​​of wind speed and wave height. Wind and wave patterns were analyzed by WRPlot and continued with mapping of wind and wave patterns in the waters of Kalianget-Kangean and its surroundings. The data used was obtained from the Meteorology, Climatology and Geophysics Agency. The results show wind and wave characteristics with two peaks formed regularly between 2008-2017, marking the west and east monsoons. In addition, the wind speed and wave height were generally below the danger threshold, ie <10 knots and <2 m, respectively. However, there are exceptions in the west season, especially at the peak in January, where the forces are strengthened with a steady blowing direction. The maximum wind speed reaches and wave height reaches 29 knots and 6.7 m, respectively. The weekly conditions for both parameters from December 2017 to February 2018 were relatively safe, for sailing. Moreover, January 23-29, 2018 featured extreme conditions estimated as dangerous for cruise due to the respective maximum values of 25 knots and 3.8 m recorded. The channel is comparably safe, except during the western season time in December, January, February, characterized by wind speeds and wave height exceeding 21 knots and 2.5 m, correspondingly.

scholarly journals Mean Zonal Drift Velocities of Plasma Bubbles Estimated from Keograms of Nightglow All-Sky Images from the Brazilian Sector

2019 ◽  
Author(s):  
Fabio Vargas ◽  
Christiano Brum ◽  
Pedrina Terra ◽  
Delano Gobbi
Keyword(s):  
Standard Deviation ◽  
Drift Velocity ◽  
Velocity Estimation ◽  
Plasma Bubble ◽  
The West ◽  
Equatorial Station ◽  
Plasma Bubbles ◽  
Latitude Station ◽  
The Mean

We present in this work a method for estimation of plasma bubble mean zonal drift velocities using keograms generated from images of the OI 6300.0 nm nightglow emission collected from an equatorial station -- Cariri (7.4$^\circ$S, 36.5$^\circ$W), and a mid-latitude station -- Cachoeira Paulista (22.7$^\circ$S, 45$^\circ$W), both in the Brazilian sector. The mean zonal drift velocities were estimated for 239 events recorded from 2000 to 2003 in Cariri, and for 56 events recorded over Cachoeira Paulista from 1998 to 2000. It was found that plasma bubble zonal drift velocities are smaller ($\sim$60 ms$^{-1}$) for events occurring later in the night compared to those occurring earlier ($\sim$150 ms$^{-1}$). The decreasing rate of the zonal drift velocity is of $\sim$10 ms$^{-1}$/h. We have also found that, in general, bubble events appearing first in the west-most region of the keogram are faster than those appearing first in the east-most region of the keograms. Larger zonal drift velocities occur from 19 LT to 23 LT in a longitude range from 37$^\circ$ to 33$^\circ$. The method of velocity estimation using keograms compares favorably against the mosaic method developed by \cite{Arruda:2005}, but the standard deviation of the residuals for the zonal drift velocities from the two methods is $\sim$15 ms$^{-1}$

Sign in / Sign up

Export Citation Format

Share Document