Journal Articles
Permanent URI for this collectionhttps://mro.massey.ac.nz/handle/10179/7915
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Item Reproductive biology of male common dolphins (Delphinus delphis) in New Zealand waters.(Springer Nature, 2023-10-06) Palmer EI; Betty EL; Murphy S; Perrott MR; Smith ANH; Stockin KA; Siebert UReproductive parameters were assessed in 64 male common dolphins (Delphinus delphis) examined post-mortem from strandings and bycatch in New Zealand between 1999 and 2020. The stages of male sexual maturation were assessed using morphological measurements and histological examination of testicular tissue. Age was determined via growth layer groups (GLGs) in teeth. The average age (ASM) and length (LSM) at attainment of sexual maturity were estimated to be 8.8 years and 198.3 cm, respectively. Individual variation in ASM (7.5–10 years) and LSM (190–220 cm) was observed in New Zealand common dolphins. However, on average, sexual maturity was attained at a similar length but at a marginally younger age (< 1 year) in New Zealand compared to populations in the Northern Hemisphere. All testicular variables proved better predictors of sexual maturity compared to demographic variables (age and total body length), with combined testes weight the best outright predictor of sexual maturity. Reproductive seasonality was observed in male common dolphins, with a significant increase in combined testes weight in austral summer. This aligns with most other studied populations, where seasonality in reproduction is typically observed. Given the known anthropogenic impacts on New Zealand common dolphins, we recommend that these findings be used as a baseline from which to monitor population-level changes as part of conservation management efforts.Item When and how to say goodbye: An analysis of Standard Operating Procedures that guide end-of-life decision-making for stranded cetaceans in Australasia(Elsevier Ltd, 2022-04) Boys RM; Beausoleil NJ; Betty EL; Stockin KAStandard Operating Procedures (SOPs) are tools used to ensure management best practice during emergency incidents including wildlife interventions, such as cetacean strandings. The compromised state of stranded cetaceans means humane end-of-life decisions may be considered, and SOPs frequently guide this process. This study evaluated SOPs for end-of-life decision-making and technically enacting euthanasia of stranded cetaceans across Australasia. The aim was to highlight similarities and differences in management and explore directions to improve stranded cetacean welfare. SOPs were requested from the eight government authorities across Australia and New Zealand. All SOPs were evaluated for decision-making criteria, yielding 29 parameters for the implementation of end-of-life decisions. Euthanasia and palliative care were options for end-of-life, with palliative care recommended when euthanasia was not feasible or presented human safety risks. Three euthanasia methods were recommended. Ballistics was recommended in seven SOPs, chemicals in five and explosives in three SOPs. Variability existed in the exact procedures and equipment recommended in all three methods. Additionally, only five SOPs provided criteria for verifying death, while only two recommended time-to-death be recorded, hindering evaluation of the welfare impacts of end-of-life decisions and euthanasia procedures. Our findings highlight the need for detailed guidance and consistency in end-of-life decisions and euthanasia techniques to ensure reliable welfare outcomes. Systematic, standardised data collection at euthanasia events across regions is required to facilitate assessment of welfare impacts and develop evidence-based recommendations. International collaboration is key to developing objective criteria necessary to ensure consistent guidance for end-of-life decisions.Item Marine mammal conservation: over the horizon(Inter-Research, 2021-03-25) Nelms SE; Alfaro-Shigueto J; Arnould JPY; Avila IC; Nash SB; Campbell E; Carter MID; Collins T; Currey RJC; Domit C; Franco-Trecu V; Fuentes MMPB; Gilman E; Harcourt RG; Hines EM; Hoelze AR; Hooker SK; Johnston DW; Kelkar N; Kiszka JJ; Laidre KL; Mangel JC; Marsh H; Maxwe SM; Onoufriou AB; Palacios DM; Pierce GJ; Ponnampalam LS; Porter LJ; Russell DJF; Stockin KA; Sutaria D; Wambiji N; Weir CR; Wilson B; Godley BJ; McMahon CMarine mammals can play important ecological roles in aquatic ecosystems, and their presence can be key to community structure and function. Consequently, marine mammals are often considered indicators of ecosystem health and flagship species. Yet, historical population declines caused by exploitation, and additional current threats, such as climate change, fisheries bycatch, pollution and maritime development, continue to impact many marine mammal species, and at least 25% are classified as threatened (Critically Endangered, Endangered or Vulnerable) on the IUCN Red List. Conversely, some species have experienced population increases/recoveries in recent decades, reflecting management interventions, and are heralded as conservation successes. To continue these successes and reverse the downward trajectories of at-risk species, it is necessary to evaluate the threats faced by marine mammals and the conservation mechanisms available to address them. Additionally, there is a need to identify evidence-based priorities of both research and conservation needs across a range of settings and taxa. To that effect we: (1) outline the key threats to marine mammals and their impacts, identify the associated knowledge gaps and recommend actions needed; (2) discuss the merits and downfalls of established and emerging conservation mechanisms; (3) outline the application of research and monitoring techniques; and (4) highlight particular taxa/populations that are in urgent need of focus.Item Reproductive biology of female common dolphins (Delphinus delphis) in New Zealand waters(Springer-Verlag GmbH, 2022-11-20) Palmer EI; Betty EL; Murphy S; Perrott MR; Smith ANH; Stockin KA; Crocker DReproductive biology was assessed in 106 female common dolphins (Delphinus delphis) examined post-mortem from stranding and bycatch events along the New Zealand coastline between 1997 and 2019. The average age (ASM) and length (LSM) at sexual maturity was estimated at 7.5 years and 183.5 cm, respectively. The total number of corpora in mature individuals increased with age and appeared to persist throughout life. Ovarian asymmetry was apparent, with the left ovary displaying higher rates of ovulation, and a maximum of 19 corpora recorded for a 24-year-old female. The estimated ovulation and annual pregnancy rates for mature females were 0.39 year-1 and 30%, respectively. Conception and calving occurred year-round, with a weak seasonal increase observed in late austral spring and early austral summer. As these data did not clearly show whether seasonality was present, the gestation, lactation, and resting periods were calculated as either 12.6 or 12.8 months based on the presence/absence of seasonality, respectively. Similarly, calving interval ranged from 3.15 to 3.2 years, depending upon whether seasonality was considered. The estimated LSM of the New Zealand population aligns with other populations globally, although the estimated ASM is younger by approximately 6 months. Other reproductive parameters align with Northern Hemisphere populations, although demonstrate variation, which may reflect adaptations to local conditions such as water temperature and prey availability. As the species is subject to anthropogenic impacts including pollution and bycatch, we suggest our findings be used as a baseline with which to monitor trends in population parameters.Item Lameness prevalence and management practices on Irish pasture-based dairy farms(BioMed Central Ltd, 2022-06-08) Browne N; Hudson CD; Crossley RE; Sugrue K; Kennedy E; Huxley JN; Conneely MBackground Lameness is a painful disease, which negatively impacts dairy cow production and welfare. The aim of this observational study was to determine herd lameness prevalence, describe current lameness management practices and identify the presence of established risk factors for lameness on Irish pasture-based dairy farms. Farms were visited once during grazing (99 farms) and again during housing (85 farms). Lameness scoring was carried out at each visit (AHDB 0–3 scale); cows were classified as lame if they scored two or three. Farm management practices and infrastructure characteristics were evaluated via farmer questionnaires and direct measurements of farm infrastructure. Results Median herd-level lameness prevalence was 7.9% (interquartile range = 5.6 – 13.0) during grazing and 9.1% (interquartile range = 4.9 – 12.0) during housing; 10.9% of cows were lame at a single visit and 3.5% were lame at both visits (chronically lame or had a repeat episode of lameness). Fifty-seven percent of farmers were not familiar with lameness scoring and only one farm carried out lameness scoring. Only 22% of farmers kept records of lame cows detected, and 15% had a lameness herd health plan. Twenty-eight percent of farmers waited more than 48 h to treat a lame cow, and 21% waited for more than one cow to be identified as lame before treating. Six percent of farmers carried out routine trimming and 31% regularly footbathed (> 12 times per year). Twelve percent put severely lame cows in a closer paddock and 8% stated that they used pain relief to treat severely lame cows. Over 50% of farms had at least one cow track measurement that was classified as rough or very rough, and cow tracks were commonly narrow for the herd size. On 6% of farms, all cubicle beds were bare concrete (no matting or bedding) and on a further 6% of farms, there was a combination of cubicles with and without matting or bedding. On 56% of farms, all pens contained less than 1.1 cubicles per cow and on 28% of farms, a proportion of pens contained less than 1.1 cubicles per cow. Conclusions Overall, this study identified infrastructure and management practices which could be improved upon. The comparatively low lameness prevalence demonstrated, compared to fully housed systems, also highlights the benefits of a pasture-based system for animal welfare; however, there remains scope for improvement.Item Role typology for health and safety representatives(EMERALD GROUP PUBLISHING LIMITED, 1/08/2012) Harris LA; Olsen KB; Walker RJPurpose: The purpose of this paper is to focus on the development of a health and safety (HS) representative role typology that demonstrates how representatives enact their roles and improve occupational health and safety (OHS) under New Zealand law. It aims to consider the factors that influence the roles that HS representatives' assume. Design/methodology/approach: This qualitative, cross-perceptual study centres on the role enactments of eight HS representatives at two metal manufacturers. Semi-structured interviews were conducted with HS representatives, managers, workers, senior managers, OHS managers and a union convenor. "Types" were differentiated by the HS representatives' purpose, activities and OHS impacts. Findings: In total, four HS representative role "types" were identified: administrators, workshop inspectors, problem solvers and craft experts. Administrators implemented and operated OHS management systems and improved OHS management. Workshop inspectors undertook compliance and monitoring roles and improved workers' attitudes towards OHS. Problem solvers found solutions to control hazards and improved production from an OHS perspective. Craft experts applied technical knowledge to influence strategic OHS decisions. Role enactment appeared to be influenced by representatives' expert power, job roles and the organisational role definition. Representatives operating under both managerial and worker defined HS representative systems, increased worker "voice" by providing an avenue to redress OHS concerns. Practical implications: Implications arise for OHS policy, HS representative training courses and organisational/managerial support. Originality/value: The paper presents a HS representative role typology distinctively based on cross-perceptual data that also provides a more holistic perspective of the HS representative role by considering representatives' purpose, role enactment and OHS impact. © Emerald Group Publishing Limited.Item Decision-making for foot-and-mouth disease control: Objectives matter.(2016-06) Probert WJM; Shea K; Fonnesbeck CJ; Runge MC; Carpenter TE; Dürr S; Garner MG; Harvey N; Stevenson MA; Webb CT; Werkman M; Tildesley MJ; Ferrari MJFormal decision-analytic methods can be used to frame disease control problems, the first step of which is to define a clear and specific objective. We demonstrate the imperative of framing clearly-defined management objectives in finding optimal control actions for control of disease outbreaks. We illustrate an analysis that can be applied rapidly at the start of an outbreak when there are multiple stakeholders involved with potentially multiple objectives, and when there are also multiple disease models upon which to compare control actions. The output of our analysis frames subsequent discourse between policy-makers, modellers and other stakeholders, by highlighting areas of discord among different management objectives and also among different models used in the analysis. We illustrate this approach in the context of a hypothetical foot-and-mouth disease (FMD) outbreak in Cumbria, UK using outputs from five rigorously-studied simulation models of FMD spread. We present both relative rankings and relative performance of controls within each model and across a range of objectives. Results illustrate how control actions change across both the base metric used to measure management success and across the statistic used to rank control actions according to said metric. This work represents a first step towards reconciling the extensive modelling work on disease control problems with frameworks for structured decision making.
