Investigations and Monitoring Unit

Auckland, New Zealand

Investigations and Monitoring Unit

Auckland, New Zealand
SEARCH FILTERS
Time filter
Source Type

Dunphy B.J.,University of Auckland | Landers T.J.,Investigations and Monitoring Unit | Sagar R.L.,University of Auckland | Ranjard L.,University of Auckland | Rayner M.J.,University of Auckland
Marine Ecology Progress Series | Year: 2015

Within breath-hold diving endotherms, procellariiform seabirds present an intriguing anomaly as they regularly dive to depths not predicted by allometric models. How this is achieved is not known as even basic measures of physiological diving capacity have not been undertaken in this group. To remedy this we combined time depth recorder (TDR) measurements of dive behaviour with haematology and oxygen store estimates for 3 procellariiform species (common diving petrels Pelecanoides urinatrix urinatrix; grey-faced petrels Pterodroma macro ptera gouldi; and sooty shearwaters Puffinus griseus) during their incubation phase. Among species, we found distinct differences in dive depth (average and maximal), dive duration and dives h-1, with sooty shearwaters diving deeper and for longer than grey-faced petrels and common diving petrels. Conversely, common diving petrels dove much more frequently, albeit to shallow depths, whereas grey-faced petrels rarely dived whatsoever. Such differences in dive behaviour were reflected in haematological parameters, with sooty shearwaters having higher red blood cell counts and haematocrit (Hct) values compared to common diving and grey-faced petrels; whereas common diving petrels had significantly lower Hct but possessed higher haemoglobin concentrations per cell and greater respiratory oxygen stores than both sooty shearwaters and grey-faced petrels. Such results provide the first insights into the physiological traits underpinning procellariiform dive behaviour, and confirm the trend for deep-diving seabirds to have proportionally lower blood and respiratory oxygen stores than shallow divers. © Inter-Research 2015.


Walker J.W.,Investigations and Monitoring Unit | Van Duivenboden R.,RMPro | Neale M.W.,Investigations and Monitoring Unit | Neale M.W.,University of Auckland | Neale M.W.,Golder and Asso. NZ Ltd
New Zealand Journal of Marine and Freshwater Research | Year: 2015

Microbiological contamination arising from faecal pollution is a widespread effect of human activity on aquatic systems, with management of the issue complicated because contamination sources are often unknown. Recent advances in molecular techniques have permitted the use of host-specific genetic markers to apportion sources of faecal pollution. In this study, we used a tiered approach employing faecal indicator bacteria and Bacteroidales markers to identify faecal sources in an urban setting. Canine sources were the most common source of faecal contamination, which led to a programme of education and targeted management. A single, but substantial, source of human faecal contamination was identified that was subject to corrective action and its effectiveness validated by supplementary monitoring. This study supports the use of a tiered approach for the identification of faecal contamination sources in New Zealand, including the use of faecal indicator bacteria and more complex source-tracking analysis using genetic markers. © 2015 The Royal Society of New Zealand.


Buckthought L.E.,Investigations and Monitoring Unit | Clough T.J.,Lincoln University at Christchurch | Cameron K.C.,Lincoln University at Christchurch | Di H.J.,Lincoln University at Christchurch | Shepherd M.A.,Agresearch Ltd.
New Zealand Journal of Agricultural Research | Year: 2016

The extent to which the wetted soil area of a urine patch influences surrounding pasture is relatively unknown. The study objective was to use 15N tracer to quantify pasture N uptake in the ‘wetted’ and periphery areas of a spring deposited bovine urine patch over 311 days. Ruminant 15N enriched urine was applied to soil creating a circular wetted area, ‘zone A’ (800 kg N ha−1), with and without urea fertiliser (35 kg N ha−1). Pasture yields, 15N recovery and soil inorganic-N dynamics were monitored from zone A and two peripheral zones, B and C. Fertiliser had no effect on cumulative urinary 15N recovery in pasture (50%–52%). Average cumulative pasture 15N recovery in zones A, B and C were 30.6%, 17.3% and 4.2%, respectively. Soil inorganic-15N recovery occurred in zones A and B, declining with distance from the wetted area. The results suggest an effective urine patch area of 0.95 m2 or 3.4 times the wetted area. © 2016 The Royal Society of New Zealand


Duggan I.C.,University of Waikato | Neale M.W.,Investigations and Monitoring Unit | Robinson K.V.,NIWA - National Institute of Water and Atmospheric Research | Verburg P.,NIWA - National Institute of Water and Atmospheric Research | Watson N.T.N.,University of Waikato
Aquatic Invasions | Year: 2014

The North American calanoid copepod Skistodiaptomus pallidus is an emerging invader globally, with non-indigenous populations recorded from constructed waters in New Zealand, Germany and Mexico since 2000. We examined the effects of S. pallidus establishment on the zooplankton community of a natural lake, Lake Kereta, where it was first recorded in late-2008, coincident with releases of domestically cultured grass carp (Ctenopharyngodon idella). Although not present in any of our samples prior to August 2008, S. pallidus was found in all samples collected in the subsequent five years. ANOSIM indicated zooplankton community composition significantly differed between samples collected before and after S. pallidus invasion, whether the invader was included in the analysis or not. Zooplankton species affected most greatly were the copepods Calamoecia lucasi and Mesocyclops sp., which decreased in their relative importance, and the cladocerans Bosmina meridionalis and Daphnia galeata, which increased. Rotifer species were relatively unaffected. As the length of grass carp released were >6.5 cm, direct predatory effects by this species on the zooplankton community are unlikely. Associated reductions in macrophyte biomass could explain increases in the relative abundances of planktonic cladocerans (B. meridionalis and D. galeata). However, the effect of macrophyte reduction by grass carp on zooplankton communities is considered to be limited elsewhere, while the reduced macrophyte biomass cannot explain the decrease in relative abundance of the native planktonic calanoid copepod C. lucasi. Competition between C. lucasi and S. pallidus is the most compelling explanation for the reduction in importance of the native calanoid copepod species. Skistodiaptomus pallidus appears to have undergone a "boom-and-bust" cycle in Lake Kereta, increasing in relative abundance in the first three years following establishment, before declining in importance. © 2014 The Author(s).


Buckthought L.E.,Investigations and Monitoring Unit | Clough T.J.,Lincoln University at Christchurch | Cameron K.C.,Lincoln University at Christchurch | Di H.J.,Lincoln University at Christchurch | Shepherd M.A.,Agresearch Ltd.
Agriculture, Ecosystems and Environment | Year: 2015

Urine patches are the primary source of N loss from pastoral systems due to the high N loading that occurs over a relatively small area. However, few studies have sought to determine the effect of concurrently deposited urine and fertiliser on the fate of N in pastoral systems, even though the application of fertiliser soon after grazing is commonly practised, while no studies have examined seasonal effects of any interaction. The objective of this study was therefore, to understand how the combination of fertiliser-N and urine affected fertiliser-associated NO3 - leaching losses and plant uptake of N. A two year lysimeter study was undertaken with urine (800kg Nha-1) applied in either autumn or spring. Urea fertiliser enriched with 15N was applied to these lysimeters at rates equivalent to 200 or 400kg Nha-1 per year according to the standard regional practice.Urine and fertiliser at the 400kg Nha-1 rate increased total NO3 - leaching by up to 58kgha-1 (P<0.001), from urine applied in either autumn or spring. Fertiliser applied at 200kg Nha-1 did not increase N leaching from urine patches. Fertiliser 15N recovery in drainage was <2.2% and was not affected by fertiliser rate. Pasture uptake accounted for up to 52% of the fertiliser 15N recovery and this increased with increasing fertiliser rates, even in the presence of urine. Recovery of fertiliser 15N in the soil at the end of the experiment averaged 22% with the majority of this in the top 10cm soil.These results indicate that the potential for leaching of fertiliser N, applied to a urine patch, is low, and that avoiding fertiliser application over urine patches, reduces leaching losses of fertiliser-N by <2%, which is minimal in terms of total N loss mitigation. However, at high fertiliser application rates to urine patches (i.e. 400kg Nha-1), the total N leaching from non-fertiliser (non 15N-enriched) sources can increase. Further work is required to quantify these effects at the paddock scale. The results also show that NO3 - leaching losses were greater from autumn applied urine compared to spring applied urine by up to 306kg NO3 --Nha-1. © 2015 Elsevier B.V.


Buckthought L.E.,Investigations and Monitoring Unit | Clough T.J.,Lincoln University at Christchurch | Cameron K.C.,Lincoln University at Christchurch | Di H.J.,Lincoln University at Christchurch | Shepherd M.A.,Agresearch Ltd.
New Zealand Journal of Agricultural Research | Year: 2015

Significant areas of ruminant-grazed pastures are simultaneously covered by excreted urine and fertiliser nitrogen (N). However, the effect of overlapping N inputs on nitrous oxide (N2O) emission factors has not been studied. Three rates of 15N-labelled urea fertiliser were applied with either no urine, an autumn-urine or a spring-urine application. These treatments were applied to perennial ryegrass pasture (Lolium perenne L.) and N2O fluxes were determined over 373 days using standard static closed chamber techniques. Cumulative N2O-N fluxes ranged from 766 to 4332 g N2O-N ha-1 (0.36%-0.74% of total N applied) and were lowest in the absence of urine; however, no fertiliser rate effect occurred regardless of urine presence or season of application. Urine-elevated N2O-N fluxes followed urine applications for up to 40 days, resulting in lower fertiliser contributions to the N2O-N fluxes at these times. Total 15N recoveries as N2O-N were ≤0.04% and did not differ with fertiliser rate. © 2015 The Royal Society of New Zealand.


Ming'ate F.L.M.,Kenyatta University | Rennie H.G.,Lincoln University at Christchurch | Memon A.,Investigations and Monitoring Unit
Land Use Policy | Year: 2014

Many natural resource management researchers have focused either on institutional design and evaluation or on livelihood outcomes per se without explicitly acknowledging and rigorously examining linkages between the two. Thus, a major gap in the current literature on co-management institutional arrangements is the extent to which co-management has strengthened the livelihoods of poor forest-dependent communities. This gap is addressed in this paper by developing and testing an argument that well-designed co-management arrangements have strengthened the livelihood outcomes of poor forest-dependent communities in a Kenyan case study. The hybrid analytical framework developed for this analysis situates Ostrom's (1990) design criteria for co-management institutions in the broader context of the Sustainable Livelihood Framework. It then uses this analytical framework to evaluate the Arabuko-Sokoke Forest Reserve (ASFR) co-management initiative in Kenya, based on a three-step process. First, the paper provides an overview of current institutional arrangements for governance of the ASFR co-management regime. Second, it evaluates the extent to which these governance arrangements can be characterized as devolved collaborative governance, informed by Ostrom's (1990) design principles and third, it evaluates the extent to which the livelihood outcomes of forest dependent communities that are participants in the co-management project have had their livelihoods strengthened as a result of the ASFR co-management governance arrangements. The paper demonstrates that the institutional arrangements for ASFR co-management are relatively nascent and emerging because the governance arrangements for the ASFR co-management project cannot be characterized as fully devolved de jure collaborative governance. Notwithstanding this, the findings reveal that participant forest-dependent communities in the co-management project had improved livelihoods compared to forest-dependent communities outside the co-management scheme. It is suggested that this is due to the de facto co-management arrangements. © 2014.


Neale M.W.,Investigations and Monitoring Unit | Neale M.W.,University of Auckland | Moffett E.R.,Investigations and Monitoring Unit | Moffett E.R.,University of Auckland
Ecological Engineering | Year: 2016

Stream daylighting is a radical form of restoration which aims to improve morphological, chemical and ecological condition through the re-creation of an open channel from a buried or piped channel. Whilst empirical assessments of its efficacy are lacking, it is hypothesised that the substantial changes in habitat, channel form and energy supply arising from daylighting would lead to a significant changes in stream invertebrate communities, particularly where source populations of macroinvertebrates exist upstream. In this first published study of the ecological outcomes arising from a daylighting project, changes in the invertebrate community were assessed in two reaches of an urban stream catchment in Auckland, New Zealand's largest city, which were daylighted in early 2013. The two reaches allowed a paired assessment, where one of the reaches had a large area of intact native forest in its headwaters. Stream macroinvertebrates were sampled monthly pre- and post-daylighting to assess changes in stream macroinvertebrate communities. Community composition significantly changed pre- to post-daylighting (PERMANOVA Pseudo-F = 2.0978, P= 0.0018), where communities in different reaches changed by 58% and 71%, respectively. Taxonomic richness did not change with daylighting; however taxa replacements were apparent with 44 new taxa being collected in daylighted reaches and 11 taxa disappearing. Daylighting resulted in marked changes in energy resources and improved habitat in the short-term which altered invertebrate communities from biofilm feeding collector-browser communities to algal grazer communities. Although daylighting did not fully restore these streams from the effects of urbanisation, it is one practical option for the management of urban streams. Further, the presence of a local source population was an important determinant of stream community structure. Where source populations existed upstream community responses to daylighting were greater, including increased abundances of sensitive taxa. © 2015 Elsevier B.V.


Moffett E.R.,Investigations and Monitoring Unit | Moffett E.R.,University of Auckland | Neale M.W.,Investigations and Monitoring Unit | Neale M.W.,University of Auckland | Neale M.W.,Golder Asso. NZ Ltd.
New Zealand Journal of Marine and Freshwater Research | Year: 2015

Whilst volunteer monitoring has many benefits for both volunteers and professionals, volunteer data must be validated to understand the value and potential applications of information from volunteer monitoring programmes. Our study aimed to assess the concordance between volunteer and professional data, including state and trend assessments. We compared macroinvertebrate data collected by volunteers using a simplified identification protocol to data collected by professionals following standard national protocols for collection and identification. We found that volunteer and professional macroinvertebrate data expressed as summary indices of ecological health were significantly correlated. However, the coarser level of taxonomic identification in the volunteer dataset limited the use of taxon richness as a biodiversity measure. We also demonstrated that the ability of volunteer data to detect long-term trends in ecological health is comparable to professional data. Overall, stream monitoring data collected by volunteers provided an assessment of stream health that was concordant with assessments based on data collected by professionals, indicating that volunteer data could be used to support professional monitoring programmes. © 2015 The Royal Society of New Zealand.


Lau K.E.M.,University of Auckland | Washington V.J.,University of Auckland | Fan V.,University of Auckland | Neale M.W.,University of Auckland | And 4 more authors.
Freshwater Biology | Year: 2015

In stream ecosystems, bacterial communities play an important role in nutrient and energy cycling processes as they are among the most numerous and active organisms at the basal trophic level of the stream food web. Bacterial communities in stream biofilms have been shown to correlate well with different catchment land use and therefore provide an opportunity for the development of a novel ecological indicator of stream ecosystem health. In this study, a bacterial community index (BCI) model was developed and validated using a national data set of biofilm bacterial community profiles collected from 223 streams across seven geographical regions in New Zealand. The six-component BCI model was generated using the partial least squares regression method to associate the multivariate bacterial community profile with the macroinvertebrate community index, which is a well-established indicator of stream health. Despite strong regional clustering of the bacterial community profiles, the BCI was indicative of the level of disturbance in the catchment, as shown by significant correlations with a wide range of independent indicators of water quality, macroinvertebrate community data, ecosystem functioning and catchment land-use data. The BCI was able to explain 35% of the variation in a multi-metric index incorporating ten common ecological parameters, suggesting that the stream bacterial communities could provide useful information about the ecosystem integrity. The BCI provides a novel ecosystem assessment tool, which can be used to complement existing stream health measures in the management of anthropogenic impacts on freshwater streams and rivers. © 2015 John Wiley & Sons Ltd.

Loading Investigations and Monitoring Unit collaborators
Loading Investigations and Monitoring Unit collaborators