scholarly journals Ecological Studies on Marine Algal-Dwelling Copepoda (Harpacticoida) from Wellington, New Zealand

2021 ◽  
Author(s):  
◽  
Geoffrey Richard Frederick Hicks

<p>A quantitative seasonal study has been made on aspects of the ecology of marine algal-dwelling harpacticoid copepods at Island Bay, Wellington, New Zealand. Results are based on 154 samples collected from six species of macro-algae between April 1973 and March 1974 and is the first integrated research programme into the population dynamics of members of the phytal meiobenthos. Harpacticoid species collected are listed and brief taxonomic and zoogeographic notes on selected species is given. An analysis is made of the southern hemisphere zoogeographic relationships of the N. Z. marine harpacticoid fauna and this suggests distinct affinities with the Magellanic region of South America. The numerical contribution of harpacticoids to the total phytal meiofauna shows them to be the dominant taxon. Density comparisons are made with parallel studies on the sediment meiobenthos; in general the phytal is comparable with those from sandy bottoms. Species occurrence on each algal substrate, their specific association between each seaweed and within the rocky shore algal biotope as a whole is assessed. Seasonal periodicity in population .density is variable and is dependent on the reproductive activity of individual species. Breeding data are analysed for twenty species and reveal continuous or protracted breeding seasons, providing useful comparisons with interstitial and epibenthic representatives. Substrate preference for particular algae by truly phytal-dwelling harpacticoids is demonstrated for the first time.</p>

2021 ◽  
Author(s):  
◽  
Geoffrey Richard Frederick Hicks

<p>A quantitative seasonal study has been made on aspects of the ecology of marine algal-dwelling harpacticoid copepods at Island Bay, Wellington, New Zealand. Results are based on 154 samples collected from six species of macro-algae between April 1973 and March 1974 and is the first integrated research programme into the population dynamics of members of the phytal meiobenthos. Harpacticoid species collected are listed and brief taxonomic and zoogeographic notes on selected species is given. An analysis is made of the southern hemisphere zoogeographic relationships of the N. Z. marine harpacticoid fauna and this suggests distinct affinities with the Magellanic region of South America. The numerical contribution of harpacticoids to the total phytal meiofauna shows them to be the dominant taxon. Density comparisons are made with parallel studies on the sediment meiobenthos; in general the phytal is comparable with those from sandy bottoms. Species occurrence on each algal substrate, their specific association between each seaweed and within the rocky shore algal biotope as a whole is assessed. Seasonal periodicity in population .density is variable and is dependent on the reproductive activity of individual species. Breeding data are analysed for twenty species and reveal continuous or protracted breeding seasons, providing useful comparisons with interstitial and epibenthic representatives. Substrate preference for particular algae by truly phytal-dwelling harpacticoids is demonstrated for the first time.</p>


Author(s):  
J.G. Jago ◽  
M.W. Woolford

There is a growing shortage of labour within the dairy industry. To address this the industry needs to attract more people and/or reduce the labour requirements on dairy farms. Current milk harvesting techniques contribute to both the labour requirements and the current labour shortage within the industry as the process is labour-intensive and necessitates long and unsociable working hours. Automated milking systems (AMS) have been in operation, albeit on a small scale, on commercial farms in Europe for a decade and may have the potential to address labour issues within the New Zealand dairy industry. A research programme has been established (The Greenfield Project) which aims to determine the feasibility of automated milking under New Zealand dairying conditions. A Fullwoods MERLIN AMS has been installed on a protoype farmlet and is successfully milking a small herd of 41 cows. Progress from the prototype Greenfields system offers considerable potential for implementing AMS in extensive grazing systems. Keywords: automated milking systems, dairy cattle, grazing, labour


2009 ◽  
Vol 62 ◽  
pp. 41-49 ◽  
Author(s):  
N.W. Waipara ◽  
J. Barton ◽  
L.A. Smith ◽  
H.M. Harman ◽  
C.J. Winks ◽  
...  

The accuracy of host range testing in weed biocontrol programmes using plant pathogens has been questioned prompting a research programme into the field safety record of pathogens used for weed biocontrol in New Zealand Nationwide disease surveys were conducted from 20002009 and focused on species closely related to target weeds and therefore potentially most at risk of attack These surveys identified pathogens associated with any disease symptoms observed on nontarget hosts Disease damage attributable to biocontrol agents was observed on two nontarget plants Pustules of the blackberry rust Phragmidium violaceum were found on the endemic Rubus species R cissoides (bush lawyer tataramoa) at one location This result was predicted from host range safety tests conducted prior to its arrival in New Zealand No nontarget damage was observed in the remaining case studies confirming to date that all biocontrol pathogens are highly host specific to their target weeds


2020 ◽  
Author(s):  
Michael Joy ◽  
KJ Foote ◽  
P McNie ◽  
M Piria

© 2019 CSIRO. The number of New Zealand's freshwater fish listed as threatened has increased since 1992 when the first New Zealand threat classification system list was compiled. In this study, temporal and land cover-related trends were analysed for data on freshwater fish distribution, comprising more than 20 000 records for the 47 years from January 1970 to January 2017 from the New Zealand Freshwater Fish Database. The analysis included individual species abundance and distribution trends, as well as an index of fish community integrity, namely the Index of Biotic Integrity (IBI). Of the 25 fish species that met the requirements for analysis to determine changes in the proportion of sites they occupied over time, 76% had negative trends (indicating declining occurrence). Of the 20 native species analysed for the proportion of sites occupied over time, 75% had negative trends; 65% of these were significant declines and more species were in decline at pasture sites than natural cover sites. The average IBI score also declined over the time period and, when analysed separately, the major land cover types revealed that the IBI declined at pasture catchment sites but not at sites with natural vegetation catchments.


Author(s):  
B.J. Wills ◽  
G.B. Douglas ◽  
J. Mckenzie ◽  
K.D. Trainor ◽  
A.G. Foote

Intermediate and pubescent wheatgrasses (Thinopyrum intermedium) are potentially useful as dryland forage grasses in New Zealand. The recent literature on their international and local use in pasture and cropping situations is reviewed. Under semi-arid conditions at Bendigo Station over a 13-year period, cv. Luna wheatgrass has spread several metres from the original drill lines and it provides very high ground cover. In terms of dryland soil resource conservation this contrasts with adjacent cocksfoot and, to a lesser extent, lucerne plots which have wide-spaced plants interspersed with litter and much bare ground. In a mixed drilling containing wheatgrass, hairy dorycnium, birdsfoot trefoil and sheep's burnet, the first two species now dominate. At Takapau, central Hawke's Bay, annual yields from intermediate and pubescent wheatgrasses produced over 80% of the yield of 10 New Zealand cultivars in spring, summer and autumn, and 65% in the winter. Of the wheatgrasses, cv. Topar intermediate wheatgrass and a pubescent wheatgrass (unnamed line) were the lowest yielding, whereas cv. Oahe and cv. Mandan produced the highest yields. Cv. Greenleaf pubescent wheatgrass had higher foliar nitrogen content than all other species, but in vitro organic matter digestibility was less than 700 g OM/kg DM. Although the wheatgrasses had satisfactory herbage yield and nutritional value, better alternative species are available for pastoral farming in central Hawke's Bay. On Belfield in the Hakataramea Valley, cv. Rush has been the most vigorous wheatgrass for establishment and it seems to handle cold winds and frost well. Hay made from a wheatgrass/ lucerne mix is considered better than that from the individual species as this can increase production by 40-50%, depending on soil and climatic conditions. Usually only one cut per year is taken from the mixed pasture. Crop maintenance includes the application of 200 kg/ha of sulphur super extra every 3-4 years and the pH is maintained at about 5.9-6.4 by liming. A significant advantage is that no stock health, pest or plant disease problems have been noted as yet with any of the wheatgrass varieties available in New Zealand. Keywords: dryland agriculture, New Zealand, Thinopyrum, wheatgrass


2019 ◽  
Vol 64 (No. 5) ◽  
pp. 228-230
Author(s):  
E Cermakova ◽  
M Oliveri ◽  
Z Knotkova ◽  
Z Knotek

The aim of this study was to evaluate the effectiveness of deslorelin acetate in the regulation of reproductive activity in captive leopard geckos (Eublepharis macularius). Fourteen healthy adult females were separated into two groups. Under general anaesthesia, deslorelin acetate implants (4.7 mg) or placebo implants were administered into the coelom of ten female geckos and four female geckos, respectively. One healthy adult male Leopard gecko was added to each group of females (five females with GnRH implants and two females with placebo implants). The geckos were regularly monitored over two breeding seasons (visual examination, weight control). Nesting sites were checked daily. There were no postoperative complications or any other health problems during the study. Implant administration did not result in long-term suppression of reproductive function. No significant differences were found in the number of clutches between the female groups (deslorelin implants versus placebo implants) or in the number of clutches between the two breeding seasons. Deslorelin acetate implants did not interfere with ovarian activity in captive female leopard geckos. The use of GnRH agonist implants is not an appropriate method for control of reproductive function in female leopard geckos.


1975 ◽  
Vol 15 (2) ◽  
pp. 42
Author(s):  
D. Graham Jenkins

BIOSTRATIGRAPHIC DOCUMENTATION of fossil species of planktonic foraminifera has played a major role in correlating marine Cenozoic rocks because of their relatively high diversity, abundance, rapid evolution and wide geographic distribution. A major step was undertaken in Trinidad in 1945 with the division of the Oligocene-Miocene rocks into three zones based on planktonic foraminifera and with the intensive oil-search on the island, there began an equally intensive research programme and rapid development in the study.Two research projects, independent of each other, were initiated in Gippsland. Victoria in the 1950s which resulted in publications: (1) from surface samples, a faunal unit system was devised for the Upper Eocene-Miocene. and (2) 11 named planktonic foraminiferal zones were established in a four-foot sampled Oligocene-Miocene sequence of the Lakes Entrance oil shaft. The latter scheme was tested and expanded for 3 years during oil exploration on the East Coast of New Zealand during 1959-1962 and a further four years was spent thoroughly testing, and expanding it into 21 zones sub-dividing the whole Cenozoic time of 67my. The zones can be identified in both surface and sub-surface sections and used for direct, accurate correlations of marine rock sequences thus providing the geologist with essential data for the construction of maps and subsurface control.The zonal scheme was re-exported back to South Australia, later to Gippsland and used there with minor local changes in the off-shore oil exploration; in 1973 the zonal scheme was further tested during the Deep Sea Drilling Project Leg 29 in the area south of New Zealand and Australia.Studies of planktonic foraminifera and allied microfossils has resulted in the cheapest and most reliable method for rapid age determinations of Cenozoic marine rocks; in perspective it plays a minor, but essential role in oil-search. The zonal scheme is a dynamic model subject to change and improvement.


1999 ◽  
Vol 5 (1) ◽  
pp. 16 ◽  
Author(s):  
Hiltrun Ratz ◽  
Brian Murphy

The endemic Yellow-eyed Penguin Megadyptes antipodes is threatened by habitat loss and introduced predators on mainland New Zealand. Nine colonies in the Catlins (south-east coast of South Island) were studied to measure breeding success, penguin abundance, and predator abundance in three successive breeding seasons (1991/92 to 1993/94). Nest numbers increased in all nine colonies in the three years despite predation (probably by Stoats Mustefa erminea) being the most important cause of breeding failure. Larger colonies with higher breeding success were in small gullies with limited shrubs and bushes rather than in the most intact mature forest colonies hitherto assumed to be optimal habitat for the birds. Penguin nests were concentrated near the forest edge, but predators were not, so the predation risk was not elevated near the forest edge. Fragmentation of the original forest habitat had no observable adverse effect on breeding success. Stoats dominated the predator guild, while Ferrets M. furo and Feral Cats Felis catus were rare. Trapping to kill predators early in the season had no marked effect on subsequent predation losses, but trapping intervention when a predation outbreak occurred curtailed further chick deaths. A simple population model predicts that Yellow-eyed Penguins populations will grow provided the average total chicks loss is less than 43% per season, or at least 0.85 chick per nest fledges each year. This requires predation losses to be less than 34%.


Author(s):  
Nasser Almesfer ◽  
Dmytro Y. Dizhur ◽  
Ronald Lumantarna ◽  
Jason M. Ingham

The material properties of New Zealand’s heritage clay brick unreinforced masonry (URM) buildings were investigated and are reported herein. Material data was collected from a total of 98 New Zealand clay brick URM buildings and a database was compiled that was comprised of various masonry material properties. The intention behind the reporting of information and data presented herein was to provide indicative values to the professional engineering community to aid as preliminary input when undertaking detailed building assessments for cases where in-situ testing and brick and mortar sample extraction are not feasible. The data presented is also used to support the relationships for URM material properties that have been recommended by the authors for incorporation into the next version of the NZSEE seismic assessment guidelines for URM buildings. Although researchers from Europe, USA, India and Australia have previously studied the material properties of clay brick unreinforced masonry, knowledge on New Zealand URM material properties was poor at the time the study commenced. Therefore, a research programme was undertaken that was focused on both in-situ testing and laboratory testing of samples extracted from existing New Zealand clay brick URM buildings.


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