Spatial and temporal dynamics of temperate Australian rockpool ichthyofaunas

2003 ◽  
Vol 54 (2) ◽  
pp. 163 ◽  
Author(s):  
Shane P. Griffiths

Spatial and temporal variation, and factors influencing the structure of intertidal rockpool fish assemblages were quantitatively investigated at three large rocky headlands in south-eastern New South Wales, Australia. A total of 5244 fish from 46 species, mainly permanent intertidal residents from the families Clinidae, Blenniidae, Tripterygiidae, Gobiidae, Gobiesocidae and Girellidae, was caught in the rockpools. Numbers of species and individuals and dominance patterns of species showed significant variability within locations, possibly in response to variations in rockpool tidal height and volume, or environmental variables, such as temperature and dissolved oxygen. Species composition also differed among locations, probably as a result of availability of different habitats at each location, which may be preferred by different species. Fish assemblage structure was stable and persistent through time, presumably because rockpools are colonized only by species suitably adapted to the dynamic intertidal environment. Temporal variability in the abundance of some common species occurred during summer and autumn, mainly owing to recruitment of resident fishes. Directions for future research are given, which may contribute to an understanding of the processes that underpin these patterns.






2017 ◽  
Vol 68 (7) ◽  
pp. 1391 ◽  
Author(s):  
D. Harasti ◽  
K. A. Lee ◽  
R. Laird ◽  
R. Bradford ◽  
B. Bruce

Stereo baited remote underwater video systems (stereo-BRUVs) are commonly used to assess fish assemblages and, more recently, to record the localised abundance and size of sharks. The present study investigated the occurrence and size of white sharks (Carcharodon carcharias) in the near-shore environment off Bennett’s Beach, part of a known nursery area for the species in central New South Wales, Australia. Six stereo-BRUV units were deployed approximately fortnightly between August and December 2015 for periods of 5h in depths of 7–14m. Stereo-BRUVs successfully recorded 34 separate sightings of 22 individual white sharks. The highest number of individuals detected during a single day survey was eight. All C. carcharias observed on stereo-BRUVs were juveniles ranging in size from 1.50 to 2.46-m total length (mean±s.e., 1.91±0.05m; n=22). The time to first appearance ranged from 15 to 299min (mean±s.e., 148±15min). This study demonstrates that the use of stereo-BRUVs is a viable, non-destructive method to obtain estimates of the size and presence of white sharks, and may be useful in estimating relative abundance in near-shore environments where white sharks are known to frequent.



2021 ◽  
Vol 41 (3) ◽  
pp. 643-653
Author(s):  
Thomas Newsome

Few animals in Australia evoke as much controversy as the dingo. There are debates about its cultural significance, what to call it, and its ecological and economic impacts. Resolving these debates requires consensus and agreement among researchers, land managers and other stakeholders. To aid this, I briefly summarise how far we have come in terms of increasing our knowledge of the ecology and behaviour of dingoes since the Royal Zoological Society of New South Wales held its first symposium on the dingo in 1999. I summarise the key debates that have arisen during this period, and then summarise some of the key recommendations made in papers that were written following the 2019 symposium. I finish with some suggestions for future dingo research, focusing on (1) how we can better understand and appropriately acknowledge the cultural significance of the dingo through research, broader consultations and appropriate representations on national, state and local pest planning committees, (2) produce taxonomic consensus through the appointment of an independent panel and future research using genome-wide DNA technology, and (3) resolving ecological and economic debates via reintroduction experiments in both conservation and managed agricultural landscapes. Without such efforts, I see a future for the dingo that continues to be steeped in controversy and debate.



2020 ◽  
Vol 71 (1) ◽  
pp. 68 ◽  
Author(s):  
Brendan P. Kelaher ◽  
Andrew P. Colefax ◽  
Alejandro Tagliafico ◽  
Melanie J. Bishop ◽  
Anna Giles ◽  
...  

The turbulent waters off ocean beaches provide habitat for large marine fauna, including dolphins, sharks, rays, turtles and game fish. Although, historically, these assemblages have proven difficult to quantify, we used a new drone-based approach to assess spatial and temporal variation in assemblages of large marine fauna off four exposed beaches in New South Wales, Australia. In total, 4388 individual large marine animals were identified from 216 drone flights. The most common taxa, bottlenose dolphins (Tursiops spp.) and Australian cownose rays (Rhinoptera neglecta), occurred in 25.5 and 19.9% of flights respectively. White (Carcharodon carcharias), bull (Carcharhinus leucas) and other whaler (Carcharhinus spp.) sharks were observed in <1% of flights. There was significant variation in the structure of assemblages of large fauna among beaches, with those adjacent to riverine estuaries having greater richness and abundance of wildlife. Overall, drone surveys were successful in documenting the spatio-temporal dynamics of an impressive suite of large marine fauna. We contend that emerging drone technology can make a valuable contribution to the ecological information required to ensure the long-term sustainability of sandy-beach ecosystems and associated marine wildlife.



Water ◽  
2020 ◽  
Vol 12 (11) ◽  
pp. 2974 ◽  
Author(s):  
Bunyeth Chan ◽  
Peng Bun Ngor ◽  
Zeb S. Hogan ◽  
Nam So ◽  
Sébastien Brosse ◽  
...  

Inland fisheries management in Cambodia has undergone two major policy reforms over the last two decades. These reforms led to the abolishment of a century-old commercial fishing lot system in 2012 and the establishment of new fish sanctuary and community fishing areas. However, the status of fisheries and fish assemblages following the reforms is not well understood. Here, we investigated the temporal changes in fish catch weight and fish assemblage structure for the period 1995–2000 before fishing lot abolishment (BLA) and for the period 2012–2015 after the removal of all fishing lots (after lot abolishment-ALA) using time-series fish catch data recorded from the Tonle Sap Lake (TSL), one of the world largest inland fisheries. We found (i) mean catch trends vary seasonally, with stable catch trends during the BLA and decreasing catch trends during the ALA and (ii) significant shifts in fish assemblage composition, notably a shift from large-bodied, migratory, and/or predatory species during the BLA toward more short-distance migratory and/or floodplain, small-bodied species during the ALA. Fishing lot abolishment coincided with substantial changes to floodplain habitats and increases in fishing pressure, threatening TSL fish stocks. Flow alterations caused by dams and climate change may exacerbate the problem. Therefore, to realize the fisheries reform objectives, it is imperative to strengthen the fisheries’ governance and management system, including effective law enforcement, institutional strengthening, improved planning, cooperation, and coordination as well as clearly defined roles and responsibilities among concerned stakeholders at all levels.



Author(s):  
JC Noble

Semi-arid woodlands are an important part of the Australian landscape and they have been the focus for scientific research by CSIRO since the 1960s. This book reviews that research and sets it in a historical perspective. It examines the development of pastoral science, with particular reference to the farming frontier in western New South Wales, as well as research conducted by CSIRO over the past thirty years aimed at helping manage increasing shrub densities while improving productivity. The author discusses past, current and future research directions and looks at how management perceptions and approaches continue to change as understanding of ecological processes and new strategies evolve.



2006 ◽  
Vol 28 (2) ◽  
pp. 187 ◽  
Author(s):  
S. L. Radford ◽  
J. McKee ◽  
R. L. Goldingay ◽  
R. P. Kavanagh

In 1996, guidelines were produced for capture and radio-tracking protocols for koala (Phascolarctos cinereus) research within New South Wales (NSW). An integrated project commenced in 1998 to examine P. cinereus ecology and health status in Pine Creek State Forest. This project utilised intensive clinical and pathological assessment protocols on captured P. cinereus in combination with radio-tracking and ecological investigations. The methods used in this project were referred to the NSW Koala Research Committee (KRC) for review in mid 1999 due to the political profile of the study area. The KRC assessed the project protocols and reviewed the original guidelines incorporating some of the protocols used in the Pine Creek project. The outcome is a new set of protocols for P. cinereus research within NSW which are more explicit and restrictive than those applied to P. cinereus research elsewhere or to research on other species. In their current form the new guidelines require a substantial investment in time, equipment, personnel and finance; factors that may deter or restrict future, comprehensive ecological research on P. cinereus populations. They inadequately provide for some practices we believe important in minimising the invasiveness of P. cinereus capture. We propose amendments to the guidelines in the areas of personnel required, behavioural assessment, capture methods, processing safety and tracking frequency. We suggest that these amendments will render the guidelines more accessible to a broader range of projects, and easier to apply under field conditions while preserving the intent to maintain P. cinereus welfare and research best practice.



1981 ◽  
Vol 32 (2) ◽  
pp. 227 ◽  
Author(s):  
SF Rainer ◽  
RC Fitzhardinge

The relationship between spatial patterns in the physical environment and patterns in community and trophic structure in the benthic fauna was investigated in an estuary with periodic deoxygenation of the near- bottom water. Six sites were sampled between intertidal mangroves and an 8 m deep basin of Port Hacking, N.S.W. A total of 163 species was collected, ranging from 11 to 94 at each site. Both frequency and biomass were least in the central basin and highest in a bed of the seagrass Zostera capricorni Aschers. The abundances at these sites encompass the range of values previously recorded for estuaries on the east coast of Australia. The dominant species differed from those reported from other New South Wales estuaries, although the same species were usually present. The distribution of common species was limited by fluctuations in dissolved oxygen levels, but not obviously so by sediment differences or short-term fluctuations in water temperature or salinity. Frequency-based diversity and evenness values were similar to those from other estuarine areas. Biomass-based values were lower at most sites than frequency-based values. Patterns of diversity and evenness could not be simply interpreted as indicators of environmental harshness in the community.



1991 ◽  
Vol 13 (2) ◽  
pp. 118 ◽  
Author(s):  
DJ Munnich ◽  
PC Simpson ◽  
HI Nicol

A survey of natural and improved paddocks on 34 farms was conducted over winter within a 60 km radius of Goulburn on the Southern Tablelands of New South Wales. Seventeen of the properties which were found to have significant (greater than 10 per cent) proportions of potentially useful native grasses were resurveyed in the subsequent summer to identify specific Danthonia spp. The survey revealed that useful native yearlong green species such as Microlaena stipoides and Danthonia spp. were relatively abundant in natural paddocks surveyed over winter (16 per cent and 10 per cent respectively), Danthonia being represented by four common species. These natural paddocks, most of which contained Trifolium subterraneum and had some superphosphate input, carried 80 per cent as many stock as their improved counterparts in terms of average DSE/ha. Factors such as cultivation and the presence of naturalized or sown species influenced the abundance of these species, but species differences were apparent. Cultivation reduced the abundance of Danthonia spp. but did not affect the abundance of M. stipoides, which was thus more prevalent than Danthonia spp. in improved pastures. Microlaena stipoides was also more prevalent in uncleared than cleared paddocks. The frequency of Danthonia spp. was negatively associated with high percentage frequencies of annual grasses (principally Vulpia spp.), declining by approximately 2.5 per cent for each 10 per cent increase in annual grasses over winter. The proportion of M. stipoides observed in paddocks appeared to be more influenced by sown pasture species, with lowest percentages recorded where species such as Phalaris aquatica had been sown and highest percentages where no exotic species had been introduced. The abundance of M. stipoides was affected by pH, with percentage frequency increasing as pH declined (down to pH 4 (Cacl~)), indicating the possible acid tolerance of this species. Species' percentages recorded changed with season. For example, Danthonia percentages recorded were considerably greater over summer when flowering heads were obvious than those recorded in winter. This aspect highlights the importance of recording different species during specific seasons to increase the accuracy of frequency estimates.



Sign in / Sign up

Export Citation Format

Share Document