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South Island (south + island)
Selected AbstractsEstimation of erosion and deposition volumes in a large, gravel-bed, braided river using synoptic remote sensingEARTH SURFACE PROCESSES AND LANDFORMS, Issue 3 2003Stuart N. Lane Abstract System-scale detection of erosion and deposition is crucial in order to assess the transferability of findings from scaled laboratory and small field studies to larger spatial scales. Increasingly, synoptic remote sensing has the potential to provide the necessary data. In this paper, we develop a methodology for channel change detection, coupled to the use of synoptic remote sensing, for erosion and deposition estimation, and apply it to a wide, braided, gravel-bed river. This is based upon construction of digital elevation models (DEMs) using digital photogrammetry, laser altimetry and image processing. DEMs of difference were constructed by subtracting DEM pairs, and a method for propagating error into the DEMs of difference was used under the assumption that each elevation in each surface contains error that is random, independent and Gaussian. Data were acquired for the braided Waimakariri River, South Island, New Zealand. The DEMs had a 1·0 m pixel resolution and covered an area of riverbed that is more than 1 km wide and 3·3 km long. Application of the method showed the need to use survey-specific estimates of point precision, as project design and manufacturer estimates of precision overestimate a priori point quality. This finding aside, the analysis showed that even after propagation of error it was possible to obtain high quality DEMs of difference for process estimation, over a spatial scale that has not previously been achieved. In particular, there was no difference in the ability to detect erosion and deposition. The estimates of volumes of change, despite being downgraded as compared with traditional cross-section survey in terms of point precision, produced more reliable erosion and deposition estimates as a result of the large improvement in spatial density that synoptic methods provide. Copyright © 2003 John Wiley & Sons, Ltd. [source] The use of fyke nets as a quantitative capture technique for freshwater eels (Anguilla spp.) in riversFISHERIES MANAGEMENT & ECOLOGY, Issue 4 2005D. J. JELLYMAN Abstract, Fyke netting is a convenient and effective technique for capturing freshwater eels, and catch-per-unit-effort is usually assumed to be an index of eel abundance. The present study investigated the potential of depletion fishing using baited fyke nets to obtain population estimates of longfin eels Anguilla dieffenbachii Gray, in a river in the South Island of New Zealand. The probability of capture (capture efficiency) of a single night's fishing increased with increasing size of eel, and ranged from 0.2 to 0.9 for eels <400 mm, to 0.7,0.9 for eels ,500 mm. The capture efficiency of baited vs unbaited nets was assessed in a small stream that was electric fished after netting trials were completed. Baited nets proved to be an effective method of assessing abundance of longfin eels (>400 mm) but not shortfins (A. australis Richardson); capture efficiency of the population of longfins (the sum of fyke caught and electric fished eels) was 0.4 for a single night's fyke netting, increasing to 0.8 over four nights. Comparable efficiencies for shortfins were <0.1 and 0.3 respectively. Unbaited nets were markedly less efficient for both species. [source] Catchment- and site-scale influences of forest cover and longitudinal forest position on the distribution of a diadromous fishFRESHWATER BIOLOGY, Issue 3 2005HANS S. EIKAAS Summary 1. The hydrologic connectivity between landscape elements and streams means that fragmentation of terrestrial habitats could affect the distribution of stream faunas at multiple spatial scales. We investigated how catchment- and site-scale influences, including proportion and position of forest cover within a catchment, and presence of riparian forest cover affected the distribution of a diadromous fish. 2. The occurrence of koaro (Galaxias brevipinnis) in 50-m stream reaches with either forested or non-forested riparian margins at 172 sites in 24 catchments on Banks Peninsula, South Island, New Zealand was analysed. Proportions of catchments forested and the dominant position (upland or lowland) of forest within catchments were determined using geographical information system spatial analysis tools. 3. Multivariate analysis of variance indicated forest position and proportion forested at the catchment accounted for the majority of the variation in the overall proportion of sites in a catchment with koaro. 4. Where forest was predominantly in the lower part of the catchments, the presence of riparian cover was important in explaining the proportion of sites with koaro. However, where forest was predominantly in the upper part of the catchment, the effect of riparian forest was not as strong. In the absence of riparian forest cover, no patterns of koaro distribution with respect to catchment forest cover or forest position were detected. 5. These results indicate that landscape elements, such as the proportion and position of catchment forest, operating at catchment-scales, influence the distribution of diadromous fish but their influence depends on the presence of riparian vegetation, a site-scale factor. [source] Liveweight gains of lambs from Caucasian clover/ryegrass and white clover/ryegrass swards on soils of high and low fertilityGRASS & FORAGE SCIENCE, Issue 2 2007A. D. Black Summary The high nutritive value and persistence under a wide range of climatic and soil fertility conditions make Caucasian clover a potentially useful forage legume but there is little information about the performance of livestock grazing Caucasian clover/grass swards. This study compared liveweight gains of lambs grazing Caucasian clover/perennial ryegrass and white clover/perennial ryegrass swards on high fertility (Olsen P 20 mg L,1, SO4 -S 12 mg kg,1) and low fertility (Olsen P 11 mg L,1, SO4 -S 7 mg kg,1) soils from 1998 to 2001 in the South Island of New Zealand. Mean annual liveweight gains were 1178 kg ha,1 for Caucasian clover/perennial ryegrass and 1069 kg ha,1 for white clover/perennial ryegrass swards at high fertility compared with 1094 kg ha,1 and 1015 kg ha,1, respectively, at low fertility. There was a higher mean proportion of clover in Caucasian clover/perennial ryegrass (0·19) than white clover/perennial ryegrass (0·11) swards, but there were no differences in total herbage production between the two clover/perennial ryegrass swards. The mean concentration of crude protein in the herbage of Caucasian clover (302 g kg DM,1) was higher than that in white clover (287 g kg DM,1) and grass herbage (227 g kg DM,1). Estimated mean metabolizable energy concentrations in the herbage were 12·5 MJ kg DM,1 for the two clovers and 11·6 MJ kg DM,1 for grass herbage. The difference in liveweight gain between swards on soils of high and low fertility was associated with an increase in total herbage production of similar composition and nutritive value, giving a greater number of grazing days for the swards on soils of high than low fertility. [source] Simulation of New Zealand's climate using a high-resolution nested regional climate modelINTERNATIONAL JOURNAL OF CLIMATOLOGY, Issue 9 2007Frank Drost Abstract A regional climate model (RCM) for New Zealand has been developed. The RCM is embedded within a GCM and both models are run under pre-industrial conditions. Seasonal mean output of the RCM is compared against NCEP data and the New Zealand national climate database. Regional and seasonal aspects of modelled surface temperature and precipitation are to a large extent simulated correctly. The main anomalies are related to the difficulty of incorporating New Zealand's orography appropriately and to the initial and lateral boundary conditions, which were supplied by the GCM. The largest anomalies occur over the Southern Alps, where the modelled temperatures are too low and where the amount of precipitation is too high. Many parts of the east coasts in both the North and South Island are too warm and too dry. Correlation patterns of temperature and precipitation with mean sea-level pressure differ considerably from the equivalent patterns constructed from NCEP data, but do show in general the dominant relationships between wind direction and temperature and precipitation. Copyright © 2006 Royal Meteorological Society [source] Trends in New Zealand daily temperature and rainfall extremesINTERNATIONAL JOURNAL OF CLIMATOLOGY, Issue 12 2001M.J. Salinger Abstract Trends in daily temperature and rainfall indices are described for New Zealand. Two periods were examined: 1951,1998, to describe significant trends in temperature and rainfall parameters; and 1930,1998, to ascertain the effects of two main circulation changes that have occurred in the New Zealand region around 1950 and 1976. Indices examined included frequencies of daily maximum and minimum temperatures, above and below specified percentile levels and at those levels, as well as frequencies of these above and below fixed temperature thresholds. Extreme daily rainfall intensity and frequency above the 95th percentile and the length of consecutive dry day sequences were the rainfall indices selected. There were no significant trends in maximum temperature extremes (,hot days') but a significant increase in minimum temperatures was associated with decreases in the frequency of extreme ,cold nights' over the 48-year period. There was a non-significant tendency for an increase in the frequency of maximum temperature extremes in the north and northeast of New Zealand. A decline occurred in frequency of the minimum temperature 5th percentile (,cold nights') of 10,20 days a year in many locations. Trends in rainfall indices show a zonal pattern of response, with the frequency of 1-day 95th percentile extremes decreasing in the north and east, and increasing in the west over the 1951,1996 period. Changes in the frequency of threshold temperatures above 24.9°C (25°C days) and below 0°C (frost days) are strongly linked to atmospheric circulation changes, coupled with regional warming. From 1930,1950 more south to southwest anomalous flow occurred relative to later years. In this period, 25°C days were less frequent in all areas except the northeast, and there was markedly more frost days in all but inland areas of the South Island compared with the 1951,1975 period. There was more airflow from the east and northeast from 1951 to 1975, the frequency of 25°C days increased and frost days decreased in many areas of New Zealand. In the final period examined (1976,1998), more prevalent airflow from the west and southwest was accompanied by more anticyclonic conditions. Days with a temperature of 25°C increased in the northeast only. Frost day frequencies decreased between 5 and 15 days a year in many localities, with little change in the west of the South Island and at higher elevation locations. Copyright © 2001 Royal Meteorological Society [source] Dynamics of common wasps in New Zealand beech forests: a model with density dependence and weatherJOURNAL OF ANIMAL ECOLOGY, Issue 4 2002N. D. Barlow Summary 1Nest densities of the common wasp ( Vespula vulgaris (L.)) were monitored at six sites for 13 years in the honeydew-rich southern beech ( Nothofagus spp.) forests of New Zealand's South Island. 2Densities of wasp nests were among the highest in the world, up to 30 ha ,1 , and at any one site varied approximately twofold over the study period. 3Strong but not overcompensating density dependence was identified, together with a negative effect of spring rainfall. 4The density dependence appeared to act from the number of autumn queens produced during one year to the number of mature (autumn) nests the next year, rather than through variations in queen production per nest. The same stage was also responsible for most of the variability in autumn nest numbers from year to year, with queen production per nest contributing less. 5Yearly changes in nest density could be summarized by a simple Ricker model including both density dependence and weather, thereby incorporating both previous hypotheses for the determination of wasp abundance. [source] Surviving glacial ages within the Biotic Gap: phylogeography of the New Zealand cicada Maoricicada campbelliJOURNAL OF BIOGEOGRAPHY, Issue 4 2009Kathy B. R. Hill Abstract Aim, New Zealand is an ideal location in which to investigate the roles of landscape and climate change on speciation and biogeography. An earlier study of the widespread endemic cicada Maoricicada campbelli (Myers) found two phylogeographically distinguishable major clades , northern South Island plus North Island (northern-SI + NI) and Otago. These two clades appeared to have diverged on either side of an area of the South Island known as the Biotic Gap. We sampled more intensively to test competing theories for this divergence. We aimed to discover if M. campbelli had survived within the Biotic Gap during recent glacial maxima, and if predicted areas of secondary contact between the two major clades existed. Location, New Zealand. Methods, We analysed mitochondrial DNA sequences (1520 bp; 212 individuals; 91 populations) using phylogenetic (maximum likelihood, Bayesian), population genetic (analysis of molecular variance) and molecular dating methods (Bayesian relaxed clock with improved priors). Results, We found strong geographical structuring of genetic variation. Our dating analyses suggest that M. campbelli originated 1.83,2.58 Ma, and split into the two major clades 1.45,2.09 Ma. The main subclades in the northern-SI + NI clade arose almost simultaneously at 0.69,1.03 Ma. Most subclades are supported by long internal branches and began to diversify 0.40,0.78 Ma. We found four narrow areas of secondary contact between the two major clades. We also found a difference between calling songs of the Otago vs. northern-SI + NI clades. Main conclusions, Phylogeographical patterns within M. campbelli indicate an early Pleistocene split into two major clades, followed by late Pleistocene range expansion and in situ population differentiation of subclades. The northern-SI + NI clade diversified so rapidly that the main subclade relationships cannot be resolved, and we now have little evidence for a disjunction across the Biotic Gap. Structure within the main subclades indicates rapid divergence after a common bottlenecking event, perhaps attributable to an extremely cold glacial maximum at c. 0.43 Ma. Clade structure and dating analyses indicate that M. campbelli survived in many refugia during recent glacial maxima, including within the Biotic Gap. The narrow overlap between the two major clades is attributed to recent contact during the current interglacial and slow gene diffusion. The two major clades appear to be in the early stages of speciation based on genetic and behavioural differences. [source] Genetic divergences pre-date Pleistocene glacial cycles in the New Zealand speckled skink, Oligosoma infrapunctatumJOURNAL OF BIOGEOGRAPHY, Issue 5 2008Stephanie N. J. Greaves Abstract Aim, To examine the hypothesis raised by Graham S. Hardy that Pleistocene glacial cycles suffice to explain divergence among lineages within the endemic New Zealand speckled skink, Oligosoma infrapunctatum Boulenger. Location, Populations were sampled from across the entire range of the species, on the North and South Islands of New Zealand. Methods, We sequenced the mitochondrial genes ND2 (550 bp), ND4 + tRNAs (773 bp) and cytochrome b (610 bp) of 45 individuals from 21 locations. Maximum likelihood, maximum parsimony and Bayesian methods were used for phylogenetic reconstruction. The Shimodaira,Hasegawa test was used to examine hypotheses about the taxonomic status of morphologically distinctive populations. Results, Our analysis revealed four strongly supported clades within O. infrapunctatum. Clades were largely allopatric, except on the west coast of the South Island, where representatives from all four clades were found. Divergences among lineages within the species were extremely deep, reaching over 5%. Two contrasting phylogeographical patterns are evident within O. infrapunctatum. Main conclusions, The deep genetic divisions we found suggest that O. infrapunctatum is a complex of cryptic species which diverged in the Pliocene, contrary to the existing Pleistocene-based hypothesis. Although Pleistocene glacial cycles do not underlie major divergences within this species, they may be responsible for the shallower phylogeographical patterns that are found within O. infrapunctatum, which include a radiation of haplotypes in the Nelson and Westland regions. [source] The New Zealand common smelt: biology and ecologyJOURNAL OF FISH BIOLOGY, Issue 1 2005F. J. Ward The common smelt is one of the most widespread indigenous freshwater fishes in New Zealand. One other member of the family Retropinnidae, Stokellia anisodon(Stokell), is present but is confined to a small region of the South Island. There are many diadromous as well as river and lake resident populations, the latter, sometimes a result of introductions to serve as forage fish for trout. Diadromous smelt spawn during austral autumn,winter on sand bars of lower riverine reaches. Larval stages inhabit coastal marine waters, and the postlarvae to immature stages re-enter rivers and some lowland lakes. Diadromous smelt are distinguished from lowland lake resident forms by high vertebral but low gill raker numbers and larger size and from those present in some isolated waters, by high vertebral numbers alone. Lake or reservoir resident smelt usually spawn in austral spring,summer on sandy shallows at stream mouths or along shorelines. Verified smelt ages (otolith analyses) indicate that in some populations most smelt mature and spawn after c. 1 year. Adult smelt feed on a spectrum of primarily invertebrate animals ranging from small zooplankters to insects and occasionally small fishes. Smelt are a major prey for both brown trout and rainbow trout. Adult smelt are a minor food for the Maori people. As postlarvae they are a component of a few ,whitebait' fisheries. Most smelt populations are increasingly affected by environmental changes induced by human activities. Although many studies have examined problems affecting smelt, further effort is required, along with more basic research. [source] Factors affecting recruitment of glass eels into the Grey River, New ZealandJOURNAL OF FISH BIOLOGY, Issue 5 2003D. J. Jellyman The arrival pattern of glass eels of the shortfin eel Anguilla australis and longfin eel Anguilla dieffenbachii was studied over a two successive migration seasons in the Grey River, South Island, New Zealand. Fishing was carried out on selected nights during September to November, for 3 h per night during 2000 and 2001. The number of shortfin glass eels exceeded longfins in both years; earliest glass eels (September) were larger than later glass eels (November), and longfins larger than shortfins, but there were significant differences in size between years for both species. Environmental variables affecting recruitment differed between years, but common variables for both years were sampling date, time after high tide (incoming tide preferred), time after sunset and moon phase; the influence of moon phase appeared to be expressed both through tides (spring tides preferred) and moonlight. During the year of higher discharge variability, both increasing discharge and increased turbidity were also important. [source] Women's readiness to follow milk product consumption recommendations: design and evaluation of a ,stage of change' algorithmJOURNAL OF HUMAN NUTRITION & DIETETICS, Issue 4 2001P. Gulliver Objective To investigate readiness to follow milk product consumption recommendations in two random samples of New Zealand women, using an algorithm designed and evaluated to assess the stage of change construct of the Transtheoretical Model. Protocol Women were classified according to stage of readiness to perform two goal behaviours: consumption of two or four servings of milk products per day. Stage classification, as determined by the algorithm, was evaluated by estimating mean calcium intake in each stage using a validated food frequency questionnaire. This was undertaken in two independent samples of women randomly selected from the electoral rolls of two cities in New Zealand's South Island. Results Over 60% of women were classified as maintaining an intake of two servings of milk products per day. Of those women not meeting the goal of two servings per day, 73% had no intention of increasing their consumption. Over 80% of women were in the precontemplation stage for consuming four servings of milk products per day. Mean calcium intakes were significantly higher in women classified in action and maintenance stages than in preaction stages of change for both goal behaviours. Conclusion Of those women not currently meeting the recommendation for two servings of milk products per day, most are in precontemplation, a stage characterized by resistance to change. Use of the staging algorithm developed in this study makes possible the classification of women according to their readiness to change, and thus the provision of appropriate stage-tailored advice. [source] Role of fluids in the metamorphism of the Alpine Fault Zone, New ZealandJOURNAL OF METAMORPHIC GEOLOGY, Issue 1 2001J. K. Vry Abstract Models of fluid/rock interaction in and adjacent to the Alpine Fault in the Hokitika area, South Island, New Zealand, were investigated using hydrogen and other stable isotope studies, together with field and petrographic observations. All analysed samples from the study area have similar whole-rock ,D values (,DWR = ,56 to ,30,, average = ,45,, n = 20), irrespective of rock type, degree of chloritization, location along the fault, or across-strike distance from the fault in the garnet zone. The green, chlorite-rich fault rocks, which probably formed from Australian Plate precursors, record nearly isothermal fluid/rock interaction with a schist-derived metamorphic fluid at high temperatures near 450,500°C (,D of water in equilibrium with the green fault rocks (,DH2O, green) ,,,18,; ,D of water in equilibrium with the greyschists and greyschist-derived mylonites (,DH2O, grey) , ,19, at 500°C; ,DH2O, green , ,17,; ,DH2O, grey , ,14, at 450°C). There is no indication of an influx of a meteoric or mantle-derived fluid in the Alpine Fault Zone in the study area. The Alpine Fault Zone at the surface shows little evidence of late-stage retrogression or veining, which might be attributed to down-temperature fluid flow. It is probable that prograde metamorphism in the root zone of the Southern Alps releases metamorphic fluids that at some region rise vertically rather than following the trace of the Alpine Fault up to the surface, owing to the combined effects of the fault, the disturbed isotherms under the Southern Alps, and the brittle,ductile transition. Such fluids could mix with meteoric fluids to deposit quartz-rich, possibly gold-bearing veins in the region c. 5,10 km back from the fault trace. These results and interpretations are consistent with interpretations of magnetotelluric data obtained in the South Island GeopHysical Transects (SIGHT) programme. [source] First cosmogenic 10Be constraints on LGM glaciation on New Zealand's North Island: Park Valley, Tararua Range,JOURNAL OF QUATERNARY SCIENCE, Issue 8 2008Martin S. Brook Abstract We report the first direct ages for late Quaternary glaciation on the North Island of New Zealand. Mt Ruapehu, the volcanic massif in the North Island's centre, is currently glaciated and probably sustained glaciers throughout the late Quaternary, yet no numeric ages have been reported for glacial advances anywhere on the North Island. Here, we describe cosmogenic 10Be ages of the surface layers of a glacially transported boulder and glacially polished bedrock from the Tararua Range, part of the axial ranges of the North Island. Results indicate that a limited valley glaciation occurred, culminating in recession at the end of the last glacial coldest period (LGCP, ca. 18,ka). This provides an initial age for deglaciation on the North Island during the last glacial,interglacial transition (LGIT). It appears that glaciation occurred in response to an equilibrium-line altitude (ELA) lowering of ,1400,m below the present-day mean summer freezing level. Ages for glaciation in the Tararua Range correspond closely to exposure ages for the last glacial maximum (LGM) from the lateral moraines of Cascade Valley in the South Island, and in Cobb Valley, in northern South Island. The corollary is that glaciation in the Tararua Range coincided with the phase of maximum cooling during MIS 2, prior to the Antarctic Cold Reversal (ACR), during the LGCP. Copyright © 2008 John Wiley & Sons, Ltd. [source] Millennia-long tree-ring records from Tasmania and New Zealand: a basis for modelling climate variability and forcing, past, present and future,JOURNAL OF QUATERNARY SCIENCE, Issue 7 2006Edward R. Cook Abstract Progress in the development of millennia-long tree-ring chronologies from Australia and New Zealand is reviewed from the perspective of modelling long-term climate variability there. Three tree species have proved successful in this regard: Huon pine (Lagarostrobos franklinii) from Tasmania, silver pine (L. colensoi) from the South Island of New Zealand, and kauri (Agathis australis) from the North Island of New Zealand. Each of these species is very long-lived and produces abundant quantities of well-preserved wood for extending their tree-ring chronologies back several millennia into the past. The growth patterns on these chronologies strongly correlate with both local and regional warm-season temperature changes over significant areas of the Southern Hemisphere (especially Huon and silver pine) and to ENSO variability emanating from the equatorial Pacific region (especially kauri). In addition, there is evidence for significant, band-limited, multi-decadal and centennial timescale variability in the warm-season temperature reconstruction based on Huon pine tree rings that may be related to slowly varying changes in ocean circulation dynamics in the southern Indian Ocean. This suggests the possibility of long-term climate predictability there. Copyright © 2006 John Wiley & Sons, Ltd. [source] Semiarid land rehabilitation by direct drilling in the South Island, New Zealand,plant species and establishment technologyLAND DEGRADATION AND DEVELOPMENT, Issue 5 2004B. J. Wills Abstract Large areas of the east coast and inland basins of the South Island, New Zealand, are affected by periodic drought and/or semiarid climatic conditions, particularly during cyclic El Niño climatic events. The severity of these environmental conditions places great stress on introduced and native pasture species and frequently results in poor establishment of new pastures using standard drilling techniques. The objective of this study was to determine effective, practical means of rehabilitating semiarid land (about 470,mm annual rainfall) on a site in Central Otago. A comparison of two direct drilling methods, a novel strip-seeder drill and a standard hoe-coulter drill, was conducted in a trial initiated during spring 1998. Five drought-tolerant forage species were established: wheatgrass (Thinopyron intermedium), tall oat grass (Arrhenatherum elatius), birdsfoot trefoil (Lotus corniculatus), hairy dorycnium (Dorycnium hirsutum) and bluebush (Kochia prostrata). For the 2000/2001 growing season, species established with the strip-seeder drill had an overall mean herbage biomass of 235,g,m,,2,, three-times that for the hoe-coulter drill (77,g,m,,2,, P,<,0·001). Differences in herbage biomass between species were observed, with hairy dorycnium (mean 328,g,m,,2,) producing significantly (P,<,0·001) more herbage biomass than the other species. After the third spring, the percentage ground cover recorded from transects across the strip-seeder drill plots (cf. the hoe-coulter drill) was: wheatgrass,41,per,cent (10,per,cent); tall oat grass,44,per,cent (25,per,cent); birdsfoot trefoil,25,per,cent (5,per,cent); hairy dorycnium,50,per,cent (19,per,cent); and bluebush,4,per,cent (0,per,cent). The native plant content of the resident vegetation was reduced as a result of the drilling treatments and also when fertilizer was added to undistrubed pasture. The strip-seeder drill is capable of providing superior plant growth on dryland sites even during adverse drought conditions. It produces a furrow approximately 16,cm wider than the hoe-coulter drill, exerts a greater shattering effect on the soil structure and places fertilizer at depth. It is suggested that this assists plant establishment by providing good seedling protection from wind and sun, and subsequent plant growth by allowing easier root penetration to the subsoil where nutrients and moisture are available. Copyright © 2004 John Wiley & Sons, Ltd. [source] Conservation status and causes of decline of the threatened New Zealand Long-tailed Bat Chalinolobus tuberculatus (Chiroptera: Vespertilionidae)MAMMAL REVIEW, Issue 2 2000Colin F. J. O'Donnell ABSTRACT Historical anecdotes and preliminary monitoring since 1990 indicate that New Zealand Long-tailed Bats (Chalinolobus tuberculatus, Vespertilionidae) are now rare or absent at many sites where formerly they were common. Chalinolobus tuberculatus appeared to be common throughout New Zealand in the 1800s but by 1900,30 it was becoming scarce in many districts. Formal surveys in the South Island since 1990 either failed to find C. tuberculatus, or recorded bats in low numbers. Of eight sites where transect counts were undertaken, bats were recorded frequently at two sites (45,66% of counts; Eglinton and Dart Valleys), rarely at four sites (2.4,10.7% of counts), and were not recorded at the remaining two sites despite considerable survey effort. Of 10 sites where stationary counts using automatic detector units were used, no C. tuberculatus were recorded in three areas (153 nights combined), they were found rarely at six sites (2.1,21.0% of nights; 461 nights combined) and were recorded commonly only in the Eglinton Valley (85% of 120 nights). Assertions that C. tuberculatus are ,common' and that the conservation status is ,secure' are questionable and this review supports suggestions that the species should be classed as ,Vulnerable'. Possible causes of decline have been suggested including clearance and logging of lowland forests, predation by introduced mammals and owls, competition for roost sites by introduced mammals, birds and wasps, and human interference and disturbance at roosting sites. However, authors' claims have all been speculative and unsubstantiated. There has been no research undertaken to quantify these claims, and this is required urgently. The results of these preliminary surveys provide a new baseline against which future population trends might be compared. Increased effort using standardized monitoring techniques, applied at a national level, is required to confirm the possible trends and to help identify the best sites where conservation managers may attempt to restore the population level. [source] Identifying mammalian predators from bite marks: a tool for focusing wildlife protectionMAMMAL REVIEW, Issue 1 2000P. O'B. ABSTRACT Dead Sooty Shearwater, Puffinus griseus, chicks and adults were collected from seven colonies on South Island, New Zealand in the 1993,96 breeding seasons. An estimated 97% of 118 deaths were from predation. Thirty-four definite predator bite pairs were identified on 27 carcasses. Twenty-one (78%) of the carcasses had bite pairs with intercanine distances < 9.5 mm which suggests that Stoats (Mustela erminea) were the principal predators. One chick was killed by a feral House Cat (Felis catus), and it is likely that feral Ferrets (M. furo) were responsible for a proportion of the deaths. Nearly three quarters of definite Stoat bite pairs were identified in the head region. The analyses of bite marks offers cheap and statistically reliable identification of predators provided carcasses are collected fresh and flesh is removed to examine tooth punctures in bone. [source] Contrasting mtDNA diversity and population structure in a direct-developing marine gastropod and its trematode parasitesMOLECULAR ECOLOGY, Issue 22 2009DEVON B. KEENEY Abstract The comparative genetic structure of hosts and their parasites has important implications for their coevolution, but has been investigated in relatively few systems. In this study, we analysed the genetic structure and diversity of the New Zealand intertidal snail Zeacumantus subcarinatus (n = 330) and two of its trematode parasites, Maritrema novaezealandensis (n = 269) and Philophthalmus sp. (n = 246), using cytochrome c oxidase subunit I gene (COI) sequences. Snails and trematodes were examined from 11 collection sites representing three regions on the South Island of New Zealand. Zeacumantus subcarinatus displayed low genetic diversity per geographic locality, strong genetic structure following an isolation by distance pattern, and low migration rates at the scale of the study. In contrast, M. novaezealandensis possessed high genetic diversity, genetic homogeneity among collection sites and high migration rates. Genetic diversity and migration rates were typically lower for Philophthalmus sp. compared to M. novaezealandensis and it displayed weak to moderate genetic structure. The observed patterns likely result from the limited dispersal ability of the direct developing snail and the utilization of bird definitive hosts by the trematodes. In addition, snails may occasionally experience long-distance dispersal. Discrepancies between trematode species may result from differences in their effective population sizes and/or life history traits. [source] New Zealand phylogeography: evolution on a small continentMOLECULAR ECOLOGY, Issue 17 2009GRAHAM P. WALLIS Abstract New Zealand has long been a conundrum to biogeographers, possessing as it does geophysical and biotic features characteristic of both an island and a continent. This schism is reflected in provocative debate among dispersalist, vicariance biogeographic and panbiogeographic schools. A strong history in biogeography has spawned many hypotheses, which have begun to be addressed by a flood of molecular analyses. The time is now ripe to synthesize these findings on a background of geological and ecological knowledge. It has become increasingly apparent that most of the biota of New Zealand has links with other southern lands (particularly Australia) that are much more recent than the breakup of Gondwana. A compilation of molecular phylogenetic analyses of ca 100 plant and animal groups reveals that only 10% of these are even plausibly of archaic origin dating to the vicariant splitting of Zealandia from Gondwana. Effects of lineage extinction and lack of good calibrations in many cases strongly suggest that the actual proportion is even lower, in keeping with extensive Oligocene inundation of Zealandia. A wide compilation of papers covering phylogeographic structuring of terrestrial, freshwater and marine species shows some patterns emerging. These include: east,west splits across the Southern Alps, east,west splits across North Island, north,south splits across South Island, star phylogenies of southern mountain isolates, spread from northern, central and southern areas of high endemism, and recent recolonization (postvolcanic and anthropogenic). Excepting the last of these, most of these patterns seem to date to late Pliocene, coinciding with the rapid uplift of the Southern Alps. The diversity of New Zealand geological processes (sinking, uplift, tilting, sea level change, erosion, volcanism, glaciation) has produced numerous patterns, making generalizations difficult. Many species maintain pre-Pleistocene lineages, with phylogeographic structuring more similar to the Mediterranean region than northern Europe. This structure reflects the fact that glaciation was far from ubiquitous, despite the topography. Intriguingly, then, origins of the flora and fauna are island-like, whereas phylogeographic structure often reflects continental geological processes. [source] Three-genome mosses: complex double allopolyploid origins for triploid gametophytes in SphagnumMOLECULAR ECOLOGY, Issue 7 2009ERIC F. KARLIN Abstract This paper documents the occurrence of allotriploidy (having three differentiated genomes) in gametophytes of two Southern Hemisphere Sphagnum species (S. australe, S. falcatulum). The pattern of microsatellite alleles indicates that both species are composed of a complex of allodiploid and allotriploid gametophytes, with the latter resulting from two allopolyploidization events. No haploid (n = x) gametophytes were found for either species. The ploidal levels suggested by the pattern of microsatellite alleles were confirmed by flow cytometry and Feulgen DNA image densitometry. For both S. australe and S. falcatulum, the respective allodiploid plants (or their ancestors) are one of the parent species of the allotriploid plants. This is the first report of triploidy in Sphagnum gametophytes occurring in nature and also the first report of the presence of three differentiated genomes in any bryophyte. It is also the first report of intersectional allopolyploidy in Sphagnum, with S. australe appearing to have parental species from Sphagnum sections Rigida and Sphagnum, and S. falcatulum having parental species from Sphagnum sections Cuspidata and Subsecunda. In both species, the allotriploid cytotypes were the most prevalent cytotype on the South Island of New Zealand. The pattern of microsatellite alleles shows the presence of two genetically distinct populations of allodiploid S. australe, possibly indicating multiple origins of polyploidy for that allodiploid cytotype. Morphological evidence is also highly indicative of recurrent polyploidy in the allotriploid cytotype of S. falcatulum. Allopolyploidy has clearly played a major evolutionary role in these two Southern Hemisphere taxa. This study, in conjunction with other recent research, indicates that allopolyploidy is a common, if not the predominant, form of polyploidy in Sphagnum. [source] Across the Southern Alps by river capture?MOLECULAR ECOLOGY, Issue 10 2000Freshwater fish phylogeography in South Island, New Zealand Abstract We used DNA analysis of galaxiid fish to test a hypothesis of localized headwater capture in South Island, New Zealand. The restricted western, but widespread eastern, distributions of three nonmigratory freshwater fish species suggest that part of the east-flowing Waiau River has been captured by the west-flowing Buller River. However, mitochondrial control region (Kimura 2-parameter distance = 4.1,5.4%) and microsatellite flanking sequences do not support a relationship between Waiau (N = 4 fish sequences) and western populations (N = 8) of Galaxias vulgaris. Instead, the point of capture is probably to the north-east, perhaps the Nelson lakes region. Phylogenetic analysis indicates that western populations, along with populations in the north-east (N = 18), represent a previously unidentified monophyletic Evolutionarily Significant Unit, possibly a cryptic species. We suggest a general caveat for zoogeographic conclusions based on distributional data alone. [source] Phylogeographical pattern correlates with Pliocene mountain building in the alpine scree weta (Orthoptera, Anostostomatidae)MOLECULAR ECOLOGY, Issue 6 2000S. A. Trewick Abstract Most research on the biological effects of Pleistocene glaciation and refugia has been undertaken in the northern hemisphere and focuses on lowland taxa. Using single-strand conformation polymorphism (SSCP) analysis and sequencing of mitochondrial cytochrome oxidase I, we explored the intraspecific phylogeography of a flightless orthopteran (the alpine scree weta, Deinacrida connectens) that is adapted to the alpine zone of South Island, New Zealand. We found that several mountain ranges and regions had their own reciprocally monophyletic, deeply differentiated lineages. Corrected genetic distance among lineages was 8.4% (Kimura 2-parameter [K2P]) / 13% (GTR + I + ,), whereas within-lineage distances were only 2.8% (K2P) / 3.2% (GTR + I + ,). We propose a model to explain this phylogeographical structure, which links the radiation of D. connectens to Pliocene mountain building, and maintenance of this structure through the combined effects of mountain-top isolation during Pleistocene interglacials and ice barriers to dispersal during glacials. [source] Landslide events on the West Coast, South Island, 1867,2002NEW ZEALAND GEOGRAPHER, Issue 1 2005J. L. Benn Abstract:, A new landslide event inventory based on a literature search has been compiled for the West Coast of New Zealand. Rainfall has been identified as the most frequent reported landslide generating mechanism by far, followed by other/unknown means, then earthquakes. Small-magnitude, high-frequency, rainfall-induced events have historically caused the most damage to property and infrastructure, with many of the region's highways and settlements being repeatedly affected by landslides. Since 1874, landslides have caused at least 36 fatalities in the region. More historical research is needed to fill chronological and geographical gaps in the record, and to complement scientific research. Such information is useful for hazard planning purposes. [source] Spatial Scale and the Geography of Tobacco Smoking in New Zealand: A Multilevel PerspectiveNEW ZEALAND GEOGRAPHER, Issue 2 2003GRAHAM MOON ABSTRACT Smoking in New Zealand is more common in deprived areas and in areas with a significant Maori population. Despite its status as a major health problem there has been little work investigating this apparent geography of smoking Data from the 1996 Census is used to construct a multilevel ,proportions-as-responses' model of smoking prevalence. This enables an exploration of the geography of smoking at different spatial scales. Levels within the model distinguish contextual variation between local authorities, census area units and meshblocks. Particular account is taken of the influence of deprivation and ethnicity on smoking. Results confirm the importance of ethnicity and deprivation and indicate that cross-level interaction between meshblock and census area unit measures is significant. They also challenge crude stereotypes about the apparent geography of smoking and suggest that, while levels of smoking may be high in parts of North Island, they are less high than might be expected given the socio-demographic composition of the areas concerned. Conversely, smoking is more prevalent than expected in parts of South Island. The paper notes the health policy implications of these emergent geographies. [source] Macrophytes in Urban Stream Rehabilitation: Establishment, Ecological Effects, and Public PerceptionRESTORATION ECOLOGY, Issue 3 2006Scott T. Larned Abstract Efforts to rehabilitate degraded urban streams generally focus on improving physical habitat and rarely include reestablishing biota such as macrophytes. Our objectives in this study were to propagate and transplant native macrophytes into a South Island, New Zealand, urban stream undergoing rehabilitation, assess macrophyte survival and growth, and determine whether native macrophytes suppress non-native macrophytes and/or enhance stream invertebrate communities. Effects of native macrophytes on invertebrates and non-native macrophytes were assessed after transplanting patches of native macrophytes into a 230-m-long stream section. A 100-m-long section upstream was left unplanted for subsequent comparisons. Following the study, a survey was conducted to gauge public opinion about the rehabilitation project and determine whether macrophytes were prominent in perceptions of stream health. In the first growing season, native macrophyte cover in the planted stream section increased from 1.5 to 20%, and then decreased during winter. Regrowth from rhizomes led to rapid aboveground growth during the second year, when cover reached 51%. Non-native macrophytes colonized the stream the first year, but native macrophytes appeared to limit the spread of non-natives, which were absent in the planted section by the second spring. Native macrophyte establishment did not enhance invertebrate communities as predicted; few invertebrate metrics differed significantly between the planted and unplanted sections. Pollution- and sediment-tolerant invertebrate taxa were abundant in both sections, suggesting that invertebrate colonization was limited by water quality or sedimentation, not macrophyte composition. Survey respondents considered the stream to be visually and ecologically improved after rehabilitation, and macrophyte establishment was generally considered positive or neutral. [source] Polymorphism of the ovine ,3 -adrenergic receptor gene (ADRB3) and its association with wool mean staple strength and yieldANIMAL GENETICS, Issue 6 2009R. H. Forrest Summary We investigated the possibility that variation in ovine ADRB3 is associated with various wool traits, in particular mean staple strength (MSS). Polymerase chain reaction-single strand conformational polymorphism analysis of part of the ADRB3 intron was used to genotype 695 Merino lambs born on three farms in the South Island of New Zealand and which were shorn as 2-tooths. For each fleece, MSS, mean fibre diameter, mean staple length and yield were measured. The results from mixed-effects models and half-sib analyses suggest that ADRB3 alleles A and D have a negative impact on some wool traits, whereas ADRB3 alleles C and E appear to have a positive impact, with allele C potentially having a greater impact than allele E on MSS. This variation in the ADRB3 may assist in the genetic selection for increased MSS and yield in Merino sheep. [source] Spatial analysis of oblique photo-point images for quantifying spatio-temporal changes in plant communitiesAPPLIED VEGETATION SCIENCE, Issue 2 2010P. Michel Abstract Question: Can spatial analytical techniques be used to extract quantitative measurements of vegetation communities from ground-based permanent photo-point images? Location: Mount Aspiring National Park, south-western South Island, New Zealand. Methods: Sets of ground-based photographs representing two contrasting vegetation types were selected to test two spatial analytical techniques. In the grid technique, a grid was superimposed onto the photographs and the frequency of species presence in each grid-square was calculated to estimate species abundance/cover over the defined area. In the object-oriented technique, the photographs were segmented into meaningful objects, based on the colour of the pixels and the textural patterns of the images, and the area occupied by an object in the image was used to derive species abundance/cover over the area. Results: Both techniques allow quick and easy classification of digital elements into ecologically relevant categories of vegetation components. The grid technique appeared more robust, being quick and efficient, accommodating all image types and providing presence/absence matrices for multivariate analysis. Fewer classes were identified using the object-oriented technique, in particular for the forest interior site and for small individual plants such as Astelia spp. Conclusions: Both techniques showed potential for the objective quantitative analysis of long-term vegetation monitoring of cover and changes of several component species, using repeat ground-based photographs more specifically for grassland habitats. However, both rely to various degrees on manual classification. Corrective factors and strict protocols for taking the photographs are necessary to account for variation in view angles and to compute values more representative of absolute species abundance. [source] A high-resolution modelling case study of a severe weather event over New ZealandATMOSPHERIC SCIENCE LETTERS, Issue 3 2008Stuart Webster Abstract In this article, the ability of the Met Office Unified Model to simulate the severe weather over the South Island of New Zealand, on 8 January 2004 is investigated. Simulations were run at horizontal resolutions of between 60 and 1 km. The modelled broad-scale rainfall and wind features, most notably the area-averaged accumulated rainfall, were found to converge with resolution. At the highest resolutions, all the observed rainfall and wind features of this event were captured well by the model. Even the 12-km-resolution model is able to resolve the broad elongated ridge-like structure of the Southern Alps and qualitatively capture the main features of the rainfall and wind fields. Copyright © 2008 Royal Meteorological Society and Crown Copyright 2008, published by John Wiley & Sons, Ltd. [source] Anzygina, a new genus for some Australasian microleafhopper species formerly placed in the genus Zygina Fieber (Cicadellidae: Typhlocybinae: Erythroneurini)AUSTRALIAN JOURNAL OF ENTOMOLOGY, Issue 2 2009Murray J Fletcher Abstract Species of Erythroneurini (Cicadellidae: Typhlocybinae) currently placed in the genus Zygina and found in Australia, New Zealand and some neighbouring islands are transferred to the new genus Anzygina, type species Erythroneura sidnica Kirkaldy, following comparison with the type species of the genus: Typhlocyba nivea Mulsant and Rey. New combinations are Anzygina sidnica (Kirkaldy), Anzygina honiloa (Kirkaldy), Anzygina melanogaster (Kirkaldy) and Anzygina sativae (Evans) from Australia, Anzygina toetoe (Cumber), Anzygina agni (Knight), Anzygina dumbletoni (Ghauri) and Anzygina ramsayi (Knight) from New Zealand, Anzygina zealandica (Myers) from Australia and New Zealand, Anzygina jowettae (Knight) from Norfolk Island and Anzygina medioborealis (Ghauri) from Papua New Guinea. Lectotypes are designated for Erythroneura honiloa Kirkaldy and E. sidnica Kirkaldy. Anzygina billi sp.n. is described from SE Qld, and Anzygina barrattae sp.n. is described from the South Island of New Zealand. A. agni is a new record for Australia and is presumed to be Australian in origin. A. dumbletoni has a distribution which suggests that it also is introduced to New Zealand although its origins are not known. A. ramsayi, A. barrattae and A. toetoe, all of which appear to be New Zealand endemics, show affinity with each other based on aedeagal structure. A key to these species, based on males, is provided. The lack of male syntypes for Erythroneura honiala Kirkaldy and Erythroneura lubra Kirkaldy precludes establishment of their identities relative to other species of the genus, and both names are regarded as having nomen dubium status. Australian species not transferred to Anzygina are Zygina evansi (Ross) and Zygina ipoloa (Kirkaldy), both of which belong elsewhere. [source] | ||||||||||||||||||||||||||||