Diel and tidal abundance of fish larvae in a barrier-estuary channel in New South Wales

2001 ◽  
Vol 52 (7) ◽  
pp. 995 ◽  
Author(s):  
T. Trnski

In four 24-h series of ichthyoplankton sampling during winter (June–July) 1996 in Swansea Channel (which connects Lake Macquarie with coastal waters of central New South Wales, Australia) 3367 fish larvae representing at least 77 species were collected. The larval fish community clustered by sampling date and by diel phase. Diel phase had a stronger influence on abundance of more common taxa than did tide phase, and also most influence on community structure. For most taxa there was no difference in abundance between flood and ebb tides, regardless of the estuarine or marine source of the eggs and larvae. All but two of 16 common species were present in Swansea Channel throughout their entire larval stage. The sparids Acanthopagrus australis and Rhabdosargus sarbawere present in the channel only at settlement-competent sizes. These two species showed evidence of selective presence in the channel during a particular diel or tidal phase, with A. australis apparently preferring night-flood tides, which would aid migration to the estuarine nursery habitats in Lake Macquarie. The ability or inclination to escape the strong bi-directional flows in channels seems limited to only a few taxa that appear to respond to physical cues and tidal current flows.

1988 ◽  
Vol 28 (5) ◽  
pp. 561 ◽  
Author(s):  
HL Davies ◽  
E Devaud

A March-April joining of Merino ewes was compared with a June-July joining in central New South Wales at a low stocking rate on subterranean clover based pastures over 3 years. In all years, ewes joined in June were heavier (P < 0.05) than ewes joined in March (55 v. 52 kg). Liveweights at the start of lambing and liveweight change from joining to lambing were also high and favoured the later lambing group. The proportion of ewes lambing (97% March v. 93% June) and proportion of ewes twinning (29% March v. 20% June) were not significantly different between the 2 groups, but consistently favoured the March-April joining. Perinatal mortality was low (9.4% March v. 7.1% June) and not significantly different between the 2 groups, but was consistently lower in the June joined group. Number of lambs weaned per 100 ewes joined was also not significantly different, but was higher each year in the March joined group (1 13% March v. 105% June). The growth rate of the lambs (both singles [24% greater, 248 v. 200 g/day] and twins [37% greater, 2 13 v. 155 g/day]) was consistently in favour of March joined ewes. Mean greasy fleece weights of the ewes were not significantly different between the 2 groups, but were in favour of the late joined group (4.83 v. 4.50 kg). Time of joining significantly affected liveweights and greasy and clean fleece weights of the progeny at the shearing in the year following their birth in favour of March joining. These data suggest that, despite a nutritional advantage to the ewes in late pregnancy and milder weather at lambing with a June-July joining, a March- April joining is the preferred option on the Central Tablelands of New South Wales.


1989 ◽  
Vol 11 (2) ◽  
pp. 61 ◽  
Author(s):  
PJS Fleming ◽  
TJ Korn

A monthly survey involving officers from eastern New South Wales Pastures Protection Boards was conducted over four years from 1982 to 1985. Information was collected on the number and type of livestock attacked within each board district, sightings of wild dogs, the number of wild dogs kiied, the method by which they were kiied and the locations at which the observations occurred. A total of 25,644 livestock animals were reported killed or wounded from four regions; the North-East Coastal Region, the North-East Tablelands Region, the Central-East Region and South-East Region. Sheep were the most commonly attacked domestic animals followed by cattle and goats. Regional differences were apparent in the type of livestock killed and seasonal patterns of predation were evident. We recommend that annual control programmes be brought forward from June/July to late April in order to precede predation peaks.


2014 ◽  
Vol 62 (1) ◽  
pp. 100 ◽  
Author(s):  
Klaus Henle ◽  
Will Osborne ◽  
Frank Lemckert

There is increasing concern about the global decline of amphibians and reptiles. One problem with documenting declines and identifying underlying causes is the absence of historical data to compare to current data. Here we provide historic data for Kioloa on the south-eastern coast of New South Wales. In this region considerable clearing of natural forest and woodland and creation of farmland ponds took place during the second half of the 20th century. The Australian National University has a field station at Kioloa and R.E. Barwick introduced us to the field station and what was known of the herpetofauna in the mid-1980s. We undertook detailed observational surveys of the herpetofauna at this time and we revisited the area at other times, focusing on the coastal habitats. We found 13 species of frogs and 11 species of reptiles. Three further frog species and one reptile species known to occur in the area in the 1980s were not detected by us. More recently, one further frog species and six reptile species were added to the list, raising the total to 17 frog and 18 reptile species. The number and composition was similar to other locations of coastal New South Wales, except for some of the rarely encountered species. No strictly forest-dependent species were observed in the partially cleared survey area and such species presumably had already disappeared from these areas already before we commenced our observations. The frog Pseudophryne bibronii was still common in tall open-forest but was uncommon in partially cleared areas. Six species of frogs and one species of reptile presumably benefited from the anthropogenic habitat modifications. No declines of common species of reptiles occurred between the mid-1980s and 1993 but all species of frogs were very rare in 1993 due to very dry conditions. Litoria aurea, a threatened species of frog that was widespread in the mid-1980s, survives (2012) only at one site in the area.


1976 ◽  
Vol 16 (83) ◽  
pp. 871
Author(s):  
PM Dowling ◽  
RCG Smith

The objective of this study was to determine the time of year that maximized establishment and . minimized the risk of failure in aerial sowing of pasture seed on the Northern Tablelands of New South Wales. This was achieved by relating a set of monthly measurements of establishment spanning two years to mean soil moisture, predicted by a water balance model for the six-week period following sowing. From this relationship, establishment was simulated for 61 years using historical rainfall data to estimate probability density functions of establishment for each week of the year. From these functions it was concluded that maximum establishment with minimum risk can be expected from sowing in the June-July period. For perennial species plant survival over the first summer is of more practical importance than per cent establishment. Our data on plant survival, although not presented, indicated a close relationship existed between establishment and survival and supported the conclusion that the optimal time for oversowing is June-July.


1976 ◽  
Vol 16 (83) ◽  
pp. 871
Author(s):  
PM Dowling ◽  
RCG Smith

The objective of this study was to determine the time of year that maximized establishment and . minimized the risk of failure in aerial sowing of pasture seed on the Northern Tablelands of New South Wales. This was achieved by relating a set of monthly measurements of establishment spanning two years to mean soil moisture, predicted by a water balance model for the six-week period following sowing. From this relationship, establishment was simulated for 61 years using historical rainfall data to estimate probability density functions of establishment for each week of the year. From these functions it was concluded that maximum establishment with minimum risk can be expected from sowing in the June-July period. For perennial species plant survival over the first summer is of more practical importance than per cent establishment. Our data on plant survival, although not presented, indicated a close relationship existed between establishment and survival and supported the conclusion that the optimal time for oversowing is June-July.


1979 ◽  
Vol 1 (4) ◽  
pp. 363 ◽  
Author(s):  
AD Wilson ◽  
WE Mulham

The regeneration of several shrub and tree species in western New South Wales was recorded after widespread natural fires in the summer of 1974175. At 25 locations, plots were established in the wake of the fires and observations were recorded of the rue damage, the regrowth of the plants and post-fire seedling establishment. Interest was centred on species regarded as woody weeds. Fourteen months after the fires, the average survival of seven of the most common species was: Callitris columellaris (white cypress pine) 275, Acac~a aneura (mulga) 16%, Dodonaea attenuafa (narrow-leaved hopbush) 26%, Cassia eremophila var. platvpoda (punty) 48%, Acacia homalophylla (yarran) 87%, Eremophila mitchell~i (budda) 88% and Eremophila sturtii (turpentine) 87%. These results are for plants whose leaves were totally scorched or burnt. For Dodonaea attenuafa and Cassia eremophila there was a large difference in recovery between locations, a difference which was not explicable in term of fire intensity or shrub size. Post-fue seedling establishment occurred with these two shrubs, particularly with D. attenuata, which had high seedling numbers on eight of the eleven locations.


Check List ◽  
2016 ◽  
Vol 12 (6) ◽  
pp. 2008 ◽  
Author(s):  
Tom R. Davis

A study of fishes from Port Stephens in New South Wales, Australia has identified first records for three species in New South Wales — Genicanthus watanabei (Yasuda & Tominaga, 1970), Parupeneus indicus (Shaw, 1803), and Plectorhinchus chaetodonoides (Lacépède, 1801) — and southernmost records for a further four species: Cantherhines fronticinctus (Günther, 1866), Coris bulbifrons (Randall & Kuiter, 1982), Mulloidichthys vanicolensis (Valenciennes, 1831), and Paracirrhites forsteri (Schneider, 1801). New sightings were up to 980 km south of previous records, indicating prolonged survival of tropical fish larvae in the East Australian Current.


1993 ◽  
Vol 83 (4) ◽  
pp. 563-578 ◽  
Author(s):  
P. C. Gregg ◽  
G. P. Fitt ◽  
M. Coombs ◽  
G. S. Henderson

AbstractLight traps were operated between September and April for five years on towers on mountain tops at two locations in northern New South Wales, Australia. The traps were designed so that their lights could only be seen from above, and therefore only insects engaged in high altitude flight, presumed to be migrants, were captured. The catch consisted mostly of Noctuidae and Sphingidae. Sweep netting failed to reveal local breeding, and for many species there were few host plants close to the traps. A total of 51,580 moths were trapped at Point Lookout and 10,223 at Mt Dowe. Sphingids, mostly Hippotion scrofa (Boisduval), comprised 26.9% of the catch at Point Lookout, but only 2.6% at Mt Dowe, and there were more species of noctuids at Point Lookout (44) than at Mt Dowe (15). The most common noctuid species were Agrotis infusa (Boisduval), Mythimna convecta (Walker), Helicoverpa punctigera (Wallengren), H. armigera (Hübner), Dasygaster nephelistis Hampson and A. munda Walker. Known or suspected migrants comprised 94.6% of the catch at Point Lookout and 99.9% at Mt Dowe. However, there were at least 24 species not previously suspected as migrants. The seasonal distribution of catches varied between sites and years. Some species showed peaks in both spring and autumn in some years, but only in spring in other years. Many of the less common species were caught only in summer and autumn. Large catches were usually obtained overs short periods (1–2 nights), separated by long periods when catches were very low. These large catches, which were thought to represent major migrations, accounted for 76% of the catch in 3% of the trapping period at Point Lookout, and 87% of the catch in 2% of the trapping period at Mt Dowe.


1982 ◽  
Vol 33 (4) ◽  
pp. 731 ◽  
Author(s):  
RW Everett ◽  
JF Taylor ◽  
K Hammond

Month-age adjustment factors for milk and butterfat yields were estimated from 504063 lactations on 239 518 cows located in 6 145 herds in New South Wales by mixed model methods, which eliminate biases due to genetic trends, environmental trends and culling. June, July and August are the most favourable months for calving, and December and January are the least favourable, resulting in 8 to 22% less production. Friesian cows are less affected by calendar month of calving than the other breeds. Results indicate the existence of large differences between breeds in rate of maturity. Ayrshire and Jersey cows attain mature yields at a younger age than AIS, Guernsey, Friesian and AMZ cows.


1990 ◽  
Vol 38 (5) ◽  
pp. 445 ◽  
Author(s):  
S Mcintyre ◽  
RDB Whalley

A survey of 100 sites on the northern tablelands, New South Wales (Australia) was conducted to determine the composition of Vulpia populations in ruderal and pasture habitats. Of the four species recorded, two were widespread and common [Vulpia bromoides (L.) Gray and V. myuros (L.) Gmel.] and two were rare and newly recorded for the region [V. muralis (Kunth) Nees and V. ciliata (Pers.) Link]. Mixed stands of the two common species occurred at 88% of the sites sampled, although V. bromoides was more abundant with an average frequency of 61% compared with 38% for V. myuros. Two forms of V. myuros were present and these usually occurred in mixed stands, with forma myuros more widespread and abundant than forma megalura [V. megalura (Nutt.) Rydb.]. Relative frequencies were compared for a range of site characteristics: habitat type, parent material, latitude, aspect and altitude. However, variation in abundance of V. bromoides and V. myuros in relation to these factors was insignificant, suggesting that both species have a broad ecological amplitude. Although ecological differentiation between species could not be detected at the scale of this survey, it is likely that such differences may exist at a smaller spatial, or on a temporal scale.


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