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Only a small fraction of the Earth's total biodiversity has been described. This is particularly true of parasitic fauna, due to the paucity of taxonomic expertise, funding, and interest in parasites. It is expected that co-extinctions will become the main cause of species loss with potentially half of the parasite species becoming extinct prior to their discovery. This article addresses this issue and highlights case studies from the Otago Museum (OMNZ) (Dunedin, New Zealand), providing examples of successful collaborations between government organisations, museums, and parasitologists in bridging knowledge gaps in parasite diversity. The case studies presented focus on the parasitic helminths from opportunistic necropsies of stranded marine mammals and deceased birds. Collections from these case studies have doubled the size of the parasite collection at the OM, making this institution the most important repository of parasitic helminths in the country. We encourage such collaborations between museums, governing bodies, indigenous communities, ecologists and parasitologists in enhancing our knowledge of parasite diversity. Furthermore, we urge scientists to deposit both host and parasite tissues from surveys, vouchers, along with their respective metadata so that samples can be adequately stored and curated, thus ensuring that parasite collections become a legacy for future generations of scientists. [ABSTRACT FROM AUTHOR]

Gradual ocean warming combined with stronger marine heatwaves (MHWs) can reduce abundances of foundation species that control community structures, biodiversity, and ecosystem functioning. However, few studies have documented long‐term succession trajectories following the more extreme events that cause localized extinctions of foundation species. Here, we documented long‐term successional changes to marine benthic communities in Pile Bay, New Zealand, following the Tasman 2017/18 MHW, which caused localized extinctions of dominant southern bull kelp (Durvillaea sp.). Six years on, multiscale annual and seasonal surveys show no sign of Durvillaea recolonization. Instead, the invasive annual kelp (Undaria pinnatifida), rapidly colonized areas previously dominated by Durvillaea, followed by large changes to the understory community, as Durvillaea holdfasts and encrusting coralline algae were replaced by coralline turf. Between 3 and 6 years after the total loss of Durvillaea, smaller native fucoids colonized in high densities. Although Undaria initially colonized plots throughout Durvillaea's tidal range, later in the succession Undaria only retained dominance in the lower intertidal zone and only in spring. Ultimately, the tidal zone was slowly replaced by alternative foundation species, composed of different canopy‐forming brown seaweeds that dominated different intertidal elevations, resulting in a net increase in canopy and understory diversity. This study is a rare example of long‐term effects following an extreme MHW that caused extinctions of a locally dominant canopy‐former, but these events and their associated dramatic changes to community structures and biodiversity are expected to become increasingly common as MHWs continue to increase in strength, frequency, and duration. [ABSTRACT FROM AUTHOR]

Biodiversity loss is a major global challenge of the 21st century. Ultimately, extinctions of species are determined by birth and death rates; thus, conservation management of at-risk species is dependent on robust demographic data. In this study, data gathered from 381 (227 females, 154 males) long-finned pilot whales (Globicephala melas edwardii) that died in 14 stranding events on the New Zealand coast between 2006 and 2017 were used to construct the first age- and sex-specific life tables for the subspecies. Survivorship curves were fitted to these data using (1) a traditional maximum likelihood approach, and (2) Siler's competing-risk model. Life table construction and subsequent survival curves revealed distinct differences in the age- and sex-specific survival rates, with females outliving males. Both sexes revealed slightly elevated rates of mortality among the youngest age-classes (<2 years) with postweaning mortality rates decreasing and remaining relatively low until the average life expectancy is reached; 11.3 years for males and 14.7 years for females. Overall (total) mortality is estimated to be 8.8% and 6.8% per annum for males and females, respectively. The mortality curve resembles that of other large mammals, with high calf mortality, lower postweaning mortality, and an exponentially increasing risk of senescent mortality. An accelerated mortality rate was observed in mature females, in contrast to the closely related short-finned pilot whale (G. macrorhynchus), which selects for an extension to the postreproductive life span. The reason for the observed differences in the mortality rate acceleration and postreproductive life span between the two pilot whale species have not been established and warrant further investigation. Obtaining robust information on the life history of long-lived species is challenging, but essential to improve our understanding of population dynamics and help predict how future pressures may impact populations. This study illustrates how demographic data from cetacean stranding events can improve knowledge of species survival rates, thus providing essential information for conservation management. [ABSTRACT FROM AUTHOR]

Habitat modification and introduced mammalian predators are linked to global species extinctions and declines, but their relative influences can be uncertain, often making conservation management difficult. Using landscape-scale models, we quantified the relative impacts of habitat modification and mammalian predation on the range contraction of a threatened New Zealand riverine duck. We combined 38 years of whio (Hymenolaimus malacorhynchos) observations with national-scale environmental data to predict relative likelihood of occurrence (RLO) under two scenarios using bootstrapped boosted regression trees (BRT). Our models used training data from contemporary environments to predict the potential contemporary whio distribution across New Zealand riverscapes in the absence of introduced mammalian predators. Then, using estimates of environments prior to human arrival, we used the same models to hindcast potential pre-human whio distribution prior to widespread land clearance. Comparing RLO differences between potential pre-human, potential contemporary and observed contemporary distributions allowed us to assess the relative impacts of the two main drivers of decline; habitat modification and mammalian predation. Whio have undergone widespread catastrophic declines most likely linked to mammalian predation, with smaller declines due to habitat modification (range contractions of 95% and 37%, respectively). We also identified areas of potential contemporary habitat outside their current range that would be suitable for whio conservation if mammalian predator control could be implemented. Our approach presents a practical technique for estimating the relative importance of global change drivers in species declines and extinctions, as well as providing valuable information to improve conservation planning. [ABSTRACT FROM AUTHOR]

Blowflies use open wounds or the accumulation of feces or urine in wool to lay their eggs. The larvae that emerge cause lesions in the host sheep, which can lead to death. They are found in Australia, New Zealand, and the United Kingdom. Nicholson's model describes the population dynamics of the Australian blowfly (Lucilia Cuprina). It incorporates environmental variation. The extinction of these flies depends on the time to oviposition and the time between generations. The Lyapunov function, which is positive with a negative derivative, provides the condition for the stability of the equilibrium point: the oviposition period must be sufficiently short, because the shorter it is, the more it favors the extinction of the species. The zero solution is the only equilibrium point, synonymous with the extinction of the population. Another species of blowfly, Lucilia Sericata, also attacks sheep in Australia. Both blowflies are ectoparasites of warm-blooded vertebrates, particularly domestic sheep. These two blowflies are related to share same mitochondrial DNA sequences, although the two species are distinct. Presumably to avoid competition between them. the egg-laying time of each species does not occur at the same time of year: L. Sericata prefers warmer months, thus in summer, while L. Cuprina is mainly active in autumn. Laying of eggs in different months allows avoiding competition between these species. This also binds them together. A sufficiently small egglaying delay then leads to the rapid extinction of both blowfly populations, provided they do not adapt. [ABSTRACT FROM AUTHOR]

The New Zealand huia (Heteralocha acutirostris) had the most extreme bill sexual dimorphism among modern birds. Given the quick extinction of the species, the cause of the dimorphism could only be hypothesised to reflect different trophic niches and reduce male/female competition. We tested that hypothesis by combining museum specimens, geometric morphometrics, and isotopic analyses. We used geometric morphometrics to describe bill shape; measured bulk (δ15Nbulk) and (δ13Cbulk) values from feather as proxies of the birds' foraging habitat and diet; and compared compound-specific stable isotopes analyses (CSIA) of nitrogen in amino acids (δ15NAA) in male–female pairs to estimate their trophic position. Sexes had significantly different, but overlapping feather δ15Nbulk and δ13Cbulk values, but δ15NAA indicated identical trophic positions and δ15Nbulk was not related to bill shape. Trophic position was less variable among females, consistent with a specialised foraging behaviour and, thus, supporting a partial male/female foraging segregation. [ABSTRACT FROM AUTHOR]

We explored the behavioural and physiological responses of adult green-lipped mussel, Perna canaliculus by assessing synchronous measurements of mussels' cardiac activity and gaping pattern as a proxy for metabolic activity in response to decreasing temperature, oxygen concentration, or increasing anaesthetic (MgCl 2) concentration. We found that gaping magnitude of P. canaliculus , declined with decreasing temperature from 14 °C to 4 °C, with a corresponding decrease in heart rate (HR) by up to 80%. In contrast, the mussels maintained constant HRs and increased gaping magnitude with declining oxygen concentration (i.e., 8 mg O 2 L−1 to 1 mg O 2 L−1), with a depression of HR (i.e., 20% reduction from starting condition) only evident at 0.5 mg O 2 L−1, suggesting that this species is very tolerant to hypoxic conditions. MgCl 2 concentration of 30–50 g L−1 appeared to increase valve gaping and depress metabolic rate significantly as reflected in an increased relative gaping magnitude of up to 84% and a decreased HR of up to 80% respectively. These results reveal that onset of metabolic depression of P. canaliculus can be triggered below 10 °C, oxygen levels below 1 mg O 2 L−1 and MgCl 2 concentrations above 30 g L−1. Such conditions are likely to decouple the species from external disturbances and may have application potential to minimize the loss of this aquaculture species due to stress associated with harvesting and handling processes. • Heart rate of Perna canaliculus varied with temperature, oxygen and MgCl 2 levels. • P. canaliculus had decreased heart rate with declining temperature until 4 °C. • Heart rate of P. canaliculus was reduced when oxygen level dropped below 1 mg L −1. • P. canaliculus had depressed heart rate at MgCl 2 concentration beyond 30 g L −1. [ABSTRACT FROM AUTHOR]

Many ecological functions, including seed dispersal, pollination and the flow of nutrients between ecosystems, result from the movement of animals. The ongoing reduction and extinction of animal populations and species means that these functions are reduced or lost. As a result, conservation and restoration activities often seek to reinstate ecological functions to the communities from which they have been depleted.Advances in movement and allometric ecology offer a way to reconstruct the movement and emergent functions of extinct taxa. Here, we describe a framework for integrating insights from movement ecology with allometric relationships linking body mass to movement and other traits and demonstrate how this can be used to reconstruct the emergent functions of extinct taxa. Allometric relationships are best resolved for vertebrates (especially mammals), so we highlight potential gaps relevant to developing trait‐based allometric movement models for data‐depauperate taxa.To test our framework, we use it to estimate seed dispersal kernels for seven extant bird species for which seed dispersal distances are available. We then apply it to predict the movement activity and emergent seed dispersal kernels for three extinct endemic New Zealand bird species (two flightless and one volant), spanning four orders of magnitude in body mass.The model performs satisfactorily for the extant species, with predicted mean, median and maximum seed dispersal distances overlapping empirical estimates, but with a tendency to over‐prediction. If empirical data were available, the model could be calibrated for specific taxa or landscapes. The model shows that the three extinct bird species could have been important agents of long‐distance seed dispersal, and comparable functions are probably now absent in New Zealand's ecosystems.Summary. Trait‐based allometric models can be used to simulate the movement and associated functions of extinct animals. Reconstructing the functions of extinct (or data depauperate) species cannot be achieved by chaining together statistical relationships; such efforts must adequately represent natural history and carefully use computational model evaluation tools. A further challenge is adequately representing the effects of past landscape heterogeneity on disperser movement, fruit distribution and hence dispersal distances. A free Plain Language Summary can be found within the Supporting Information of this article. [ABSTRACT FROM AUTHOR]

Islands are epicenters of animal extinctions and population declines. These losses exacerbate biodiversity loss and disrupt ecological services in areas of high endemism. Island defaunation is primarily driven by invasive mammalian predators, and mammal eradications are reversing population declines for some island species. Invasive mammal eradications may also have the capacity to restore ecological interactions, along with the recovery of island fauna. Here we show that invasive mammal eradication in fenced ecosanctuaries results in higher rates of bird foraging on fruit, and higher bird‐mediated seed dispersal, than in similar forests without mammal eradication. We further show that higher foraging and seed dispersal is related to higher densities of native bird species, after accounting for natural variation in fruit availability. For the many other systems globally that are under threat from invasive mammals, New Zealand's fenced ecosanctuary model offers a promising tool for restoring biodiversity and ecosystem services. [ABSTRACT FROM AUTHOR]

Lineage through time plots (LTTs) are often used to explore past patterns of lineage diversification and community assembly. However, as they are based solely on extant species their ability to accurately depict past events can be questioned. Here, simulation models based on neutral processes are used to explore immigration and extinction scenarios to assist with interpretation of LTT plots generated from molecular clock age estimates for a nearly complete set of extant New Zealand vascular plant genera. With significant genus turnover, model simulations yield smooth exponential and linear semi-log LTT plots. Abrupt changes in extinction and immigration rates imposed in the scenarios caused only slight alterations of the curves. The vast majority of New Zealand vascular plant genera derive from trans-oceanic dispersal, and LTT plots generated from divergence dates and fossil data indicate consistently high turnover. Even major geological and climatic events leave minor signatures on LTT plots. Most notably, the maximum Oligocene Marine Transgression (27–22 Ma), when at least 85% of the current landmass was inundated, isn't clearly registered. By themselves, LTT plots shed little light on the biotic effects of climatic or geomorphic change in the remote past and need to be interpreted in the light of fossil and geological data. [ABSTRACT FROM AUTHOR]

Albatrosses are among the world's most imperiled vertebrates, with 73% of species threatened with extinction. Ingestion of plastic is a well‐recognized threat among three North Pacific species, but lesser known in the southern hemisphere, where it is considered a minor threat. As plastic entering the ocean is increasing while albatross populations decline, the threat of ocean plastic to albatross populations may be underestimated. We present case studies of 107 beach‐cast albatrosses of twelve species, received by wildlife hospitals in Australia and New Zealand, and estimate plastic ingestion and mortality rates for albatrosses in the southern hemisphere. Ingested plastic was present in 5.6% of individuals, and the cause of death in half of these cases. We estimate ingestion of plastic may cause 3.4–17.5% of nearshore mortalities and is worth consideration as a substantial threat to albatross populations. We provide clinical findings and "checklist" methodologies for identifying potential cases of foreign‐body gastrointestinal obstruction. We suggest practical policy responses, empowering decision makers to reduce albatross mortality from anthropogenic sources. [ABSTRACT FROM AUTHOR]

Invasive species are a major threat to biodiversity worldwide, causing many of the recent declines and extinctions of native species. Competition is a common mechanism through which invasive species impact the native biota. In particular, exploitative competition results when the invader outcompetes native species for essential resources, such as food and shelter sites. Despite being pervasive invaders, the ecological impacts of invasive lizards are understudied and it is often unknown whether these invaders have detrimental impacts. The plague skink (Lampropholis delicata), native to eastern Australia, has invaded several locations throughout the Pacific region (Hawaiian Islands, New Zealand, Lord Howe Island). However, no studies have documented the plague skink as having a negative impact on native species anywhere throughout its introduced range. Here, we conducted a mark‐recapture study in northern New Zealand (Shakespear Regional Park) to investigate whether the plague skink competes with native skink species (Oligosoma aeneum, O. ornatum, O. moco). Though the plague skink has a broader distribution within the study region and occurred across a broader range of habitats, there was substantial range and niche overlap between the plague skink and the three native skink species. Both the absolute capture rates and estimated population size of the plague skink were significantly higher than the three native skink species. Although plague skinks have smaller body sizes well as shorter and narrower heads than the native skink species, there was still considerable scope for dietary overlap among the species. While our study does not provide definitive evidence for competition between the plague skink and native skink species in New Zealand, we clearly demonstrate the presence of the core components required for exploitative competition to occur. Further field‐ and laboratory‐based studies will be required to confirm the existence of exploitative or interference competition by the plague skink in its introduced range. [ABSTRACT FROM AUTHOR]

Although most populations of non‐native species arriving in new environments fail to establish, mechanisms behind failed biological invasions are still poorly understood.Propagule pressure has been found to be a dominant driver of establishment success, underpinned by processes such as stochasticity and Allee effects. While studies have revealed the presence of a component Allee effect in field populations, empirical support for demographic Allee effects has been limited.We used the leaf‐feeding beetle Neolema ogloblini, a biological control agent against the plant Tradescantiafluminensis, as a proxy invasive species to experimentally study the process of establishment. We investigated how the initial size of the population released affects the probability of establishment and population growth in the first season after introduction at isolated sites in New Zealand.The probability of establishment was found to increase with numbers of individuals released. A significant quadratic relationship was found between population size released and per capita population growth rate; that is per capita population growth rate initially increased as population size released increased but decreased at higher population levels.These results support the presence of a demographic Allee effect. However, as the influence of stochasticity (environmental and demographic) could not be completely separated from that of a demographic Allee effect, we conclude that extinction probability in the experimental populations of N. ogloblini was influenced by both a demographic Allee effect and stochasticity.Our study demonstrates and supports the concept that experimental biocontrol agent releases can be used for testing hypotheses regarding invasion biology. [ABSTRACT FROM AUTHOR]

The biodiversity in soil ecosystems is simultaneously incredibly rich and poorly described. In countries such as New Zealand, where high endemism in plant species emerged following extended geographical isolation, it is likely similar evolutionary pressures extended to soil microbial communities (our biodiversity 'dark matter'). However, we have little understanding of the extent of microbial life in New Zealand soils, let alone estimates of endemism, rates of species loss or gain, or implications for systems where plants and their microbiomes have co-evolved. In this study, we tested for the impacts of land-cover type (native forest, planted forest with exotic conifers, and pastoral agriculture) on soil bacterial communities and their functional potential, using environmental microarrays (PhyloChip and GeoChip, respectively). This evaluation was conducted across four environmentally different locations (Hokitika, Banks Peninsula, Craigieburn, and Eyrewell). The environment from which samples were collected was the largest and most significant factor associated with variation in bacterial community assemblage and function. As such, novel pockets of bacterial biodiversity, with discrete ecosystem function, may be present in New Zealand. There was some evidence to suggest that change in land cover affected soil bacterial species, but not their functions. Secondary testing found this effect was restricted to differences between native forest and agricultural land use. Bacterial communities and functions between native and planted forests were similar. Analysis of soil environmental properties among samples found that land cover effects were underpinned by changes in soil pH that typically accompanies application of lime in agricultural systems, but is uncommon in planted forests. When compared with other studies conducted in New Zealand, we conclude that: (1) different locations can harbour distinct communities of soil microbial diversity, and (2) land-use intensification, not land cover change per se, shifts microbial biodiversity through alteration of primary habitat conditions, particularly soil pH. [ABSTRACT FROM AUTHOR]

Biological invasions are a global consequence of an increasingly connected world and the rise in human population size. The numbers of invasive alien species – the subset of alien species that spread widely in areas where they are not native, affecting the environment or human livelihoods – are increasing. Synergies with other global changes are exacerbating current invasions and facilitating new ones, thereby escalating the extent and impacts of invaders. Invasions have complex and often immense long‐term direct and indirect impacts. In many cases, such impacts become apparent or problematic only when invaders are well established and have large ranges. Invasive alien species break down biogeographic realms, affect native species richness and abundance, increase the risk of native species extinction, affect the genetic composition of native populations, change native animal behaviour, alter phylogenetic diversity across communities, and modify trophic networks. Many invasive alien species also change ecosystem functioning and the delivery of ecosystem services by altering nutrient and contaminant cycling, hydrology, habitat structure, and disturbance regimes. These biodiversity and ecosystem impacts are accelerating and will increase further in the future. Scientific evidence has identified policy strategies to reduce future invasions, but these strategies are often insufficiently implemented. For some nations, notably Australia and New Zealand, biosecurity has become a national priority. There have been long‐term successes, such as eradication of rats and cats on increasingly large islands and biological control of weeds across continental areas. However, in many countries, invasions receive little attention. Improved international cooperation is crucial to reduce the impacts of invasive alien species on biodiversity, ecosystem services, and human livelihoods. Countries can strengthen their biosecurity regulations to implement and enforce more effective management strategies that should also address other global changes that interact with invasions. [ABSTRACT FROM AUTHOR]

Global change is increasing biotic homogenization globally, which modifies the functioning of ecosystems. While tendencies towards taxonomic homogenization in biological communities have been extensively studied, functional homogenization remains an understudied facet of biodiversity. Here, we tested four hypotheses related to long‐term changes (1991–2016) in the taxonomic and functional arrangement of freshwater macroinvertebrate assemblages across space and possible drivers of these changes. Using data collected annually at 64 river sites in mainland New Zealand, we related temporal changes in taxonomic and functional spatial β‐diversity, and the contribution of individual sites to β‐diversity, to a set of global, regional, catchment and reach‐scale environmental descriptors. We observed long‐term, mostly climate‐induced, temporal trends towards taxonomic homogenization but functional differentiation among macroinvertebrate assemblages. These changes were mainly driven by replacements of species and functional traits among assemblages, rather than nested species loss. In addition, there was no difference between the mean rate of change in the taxonomic and functional facets of β‐diversity. Climatic processes governed overall population and community changes in these freshwater ecosystems, but were amplified by multiple anthropogenic, topographic and biotic drivers of environmental change, acting widely across the landscape. The functional diversification of communities could potentially provide communities with greater stability, resistance and resilience capacity to environmental change, despite ongoing taxonomic homogenization. Therefore, our study highlights a need to further understand temporal trajectories in both taxonomic and functional components of species communities, which could enable a clearer picture of how biodiversity and ecosystems will respond to future global changes. [ABSTRACT FROM AUTHOR]

This account presents information on all aspects of the biology of Crassula helmsii (Kirk) Cockayne (New Zealand Pygmyweed, Australian Swamp Stonecrop) that are relevant to understanding its ecological characteristics and behaviour. The main topics are presented within the standard framework of the Biological Flora of the British Isles: distribution, habitat, communities, responses to biotic factors, responses to environment, structure and physiology, phenology, floral and seed characters, herbivores and disease, history, and conservation.Crassula helmsii is an invasive aquatic macrophyte originating from Australia and New Zealand. The first naturalized population was recorded in Britain in 1956. All British specimens appear to represent a single lineage. DNA analysis indicates that British specimens originate from Australia.Crassula helmsii is capable of growing in a wide range of lentic freshwater and riparian habitats. It may grow as free floating, submerged, emergent or terrestrial forms. Morphology can differ markedly on the same stem.Flowers are produced, but with no known pollinators outside of its native range. Reproduction is thought to be predominantly by asexual methods outside Australia and New Zealand, through stem fragmentation and dispersal. Seed germination outside the native range appears to be very rare and poorly understood.Crassula helmsii has been and still is controlled by active management because of fears that its capacity to produce monocultures will lead to loss of biodiversity in the plant communities it invades. Evidence for species losses due to colonization by C. helmsii is rather anecdotal, although suppression of native biomass through competition has been reported. No consistently effective control procedures have been identified. [ABSTRACT FROM AUTHOR]

Island formation is a key driver of biological evolution, and several studies have used geological ages of islands to calibrate rates of DNA change. However, many islands are home to "relict" lineages whose divergence apparently pre‐dates island age. The geologically dynamic New Zealand (NZ) archipelago sits upon the ancient, largely submerged continent Zealandia, and the origin and age of its distinctive biota have long been contentious. While some researchers have interpreted NZ's biota as equivalent to that of a post‐Oligocene island, a recent review of genetic studies identified a sizeable proportion of pre‐Oligocene "relict" lineages, concluding that much of the biota survived an incomplete drowning event. Here, we assemble comparable genetic divergence data sets for two recently formed South Pacific archipelagos (Lord Howe; Chatham Islands) and demonstrate similarly substantial proportions of relict lineages. Similar to the NZ biota, our island reviews provide surprisingly little evidence for major genetic divergence "pulses" associated with island emergence. The dominance of Quaternary divergence estimates in all three biotas may highlight the importance of rapid biological turnover and new arrivals in response to recent climatic and/or geological disturbance and change. We provide a schematic model to help account for discrepancies between expected versus observed divergence‐date distributions for island biotas, incorporating the effects of both molecular dating error and lineage extinction. We conclude that oceanic islands can represent both evolutionary "cradles" and "museums" and that the presence of apparently archaic island lineages does not preclude dispersal origins. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • New Zealand birds of prey are examples of island gigantism. • They are closely related to much smaller Australian birds. • Island gigantism evolved within a short evolutionary time frame. • Establishment of Australian birds in NZ was facilitated by Pleistocene climate change. Abstract Prior to human arrival in the 13th century, two large birds of prey were the top predators in New Zealand. In the absence of non-volant mammals, the extinct Haast's eagle (Hieraaetus moorei), the largest eagle in the world, and the extinct Eyles' harrier (Circus teauteensis) the largest harrier in the world, had filled ecological niches that are on other landmasses occupied by animals such as large cats or canines. The evolutionary and biogeographic history of these island giants has long been a mystery. Here we reconstruct the origin and evolution of New Zealand's giant raptors using complete mitochondrial genome data. We show that both Eyles' harrier and Haast's eagle diverged from much smaller, open land adapted Australasian relatives in the late Pliocene to early Pleistocene. These events coincided with the development of open habitat in the previously densely forested islands of New Zealand. Our study provides evidence of rapid evolution of island gigantism in New Zealand's extinct birds of prey. Early Pleistocene climate and environmental changes were likely to have triggered the establishment of Australian raptors into New Zealand. Our results shed light on the evolution of two of the most impressive cases of island gigantism in the world. [ABSTRACT FROM AUTHOR]

New Zealand’s endemic King Shag ( Leucocarbo carunculatus ) has occupied only a narrow portion of the northeastern South Island for at least the past 240 years. However, pre-human Holocene fossil and archaeological remains have suggested a far more widespread distribution of the three Leucocarbo species (King, Otago, Foveaux) on mainland New Zealand at the time of Polynesian settlement in the late 13th Century CE. We use modern and ancient DNA, and morphometric and osteological analyses, of modern King Shags and Holocene fossil Leucocarbo remains to assess the pre-human distribution and taxonomic status of the King Shag on mainland New Zealand, and the resultant conservation implications. Our analyses show that the King Shag was formerly widespread around southern coasts of the North Island and the northern parts of the South Island but experienced population and lineage extinctions, and range contraction, probably after Polynesian arrival. This history parallels range contractions of other New Zealand seabirds. Conservation management of the King Shag should take into account this species narrow distribution and probable reduced genetic diversity. Moreover, combined genetic, morphometric and osteological analyses of prehistoric material from mainland New Zealand suggest that the now extinct northern New Zealand Leucocarbo populations comprised a unique lineage. Although these distinctive populations were previously assigned to the King Shag (based on morphological similarities and geographic proximity to modern Leucocarbo populations), we herein describe them as a new species, the Kohatu Shag ( Leucocarbo septentrionalis ). The extinction of this species further highlights the dramatic impacts Polynesians and introduced predators had on New Zealand’s coastal and marine biodiversity. The prehistoric presence of at least four species of Leucocarbo shag on mainland NZ further highlights its status as a biodiversity hotspot for Phalacrocoracidae. [ABSTRACT FROM AUTHOR]

The New Zealand acanthisittid wrens are the sister-taxon to all other “perching birds” (Passeriformes) and – including recently extinct species – represent the most diverse endemic passerine family in New Zealand. Consequently, they are important for understanding both the early evolution of Passeriformes and the New Zealand biota. However, five of the seven species have become extinct since the arrival of humans in New Zealand, complicating evolutionary analyses. The results of morphological analyses have been largely equivocal, and no comprehensive genetic analysis of Acanthisittidae has been undertaken. We present novel mitochondrial genome sequences from four acanthisittid species (three extinct, one extant), allowing us to resolve the phylogeny and revise the taxonomy of acanthisittids. Reanalysis of morphological data in light of our genetic results confirms a close relationship between the extant rifleman ( Acanthisitta chloris ) and an extinct Miocene wren ( Kuiornis indicator ), making Kuiornis a useful calibration point for molecular dating of passerines. Our molecular dating analyses reveal that the stout-legged wrens ( Pachyplichas ) diverged relatively recently from a more gracile ( Xenicus -like) ancestor. Further, our results suggest a possible Early Oligocene origin of the basal Lyall’s wren ( Traversia ) lineage, which would imply that Acanthisittidae survived the Oligocene marine inundation of New Zealand and therefore that the inundation was not complete. [ABSTRACT FROM AUTHOR]

For many extinct species, direct evidence of diet (e.g. coprolites, gizzard/intestinal contents) is not available, and indirect dietary evidence (e.g. stable isotopes) must be relied upon. The Late Holocene fossil record of New Zealand provides a unique opportunity to contrast palaeodietary reconstructions for the extinct moa (Aves: Dinornithiformes) using stable isotopes and coprolite/gizzard contents. Palaeodietary reconstructions from isotopes are found to contradict those based on direct dietary evidence. We discuss reasons for this and advocate, where possible, for the use of multiple lines of evidence in reconstructing the diets of extinct species. [ABSTRACT FROM AUTHOR]

New Zealand's diverse lizard fauna is under threat, particularly from predation by invasive mammals and ongoing habitat destruction. Advances in genetic techniques have greatly enhanced our understanding of the lizard fauna. Previously sparse island populations of species have recovered strongly following eradication of pest mammals and translocations of lizards to newly mammal-free islands have boosted security for some species. Recent success with intensive predator control and predator-proof fencing on the mainland shows promise for lizard populations in easily accessible sites. However, the plight of many species whose range does not include pest-free islands remains precarious and taxonomic uncertainty means we do not yet understand the full suite of species in need of protection. Further advances in predator control techniques and increased funding for lizard conservation management are needed to prevent species extinctions. [ABSTRACT FROM AUTHOR]

Christine E. Thacker, James J. Shelley, W. Tyler McCraney, Peter J. Unmack, and Matthew D. McGee, 'Delayed Adaptive Radiation among New Zealand Stream Fishes: Joint Estimation of Divergence Time and Trait Evolution in a Newly Delineated Island Species Flock', I Systematic Biology i , https://doi.org/10.1093/sysbio/syab014 The originally published version of this manuscript included a mislocalized specimen for one of the I Gobiomorphus breviceps i subpopulations. Analysis of the correct data yielded small changes in the values for divergence time estimates, inferred speciation and extinction rates, and model-fit statistics for the RevBayes and sequential trait-dependent diversification and disparity analyses. [Extracted from the article]

Megafaunal extinction followed the prehistoric human settlement of islands across the globe, but the exact duration and dynamics of the extinction processes are difficult to determine. The New Zealand moa (Aves, Dinornithiformes) are a prime example, where, despite an extensive fossil and archaeological record, debate continues about their extinction chronology and how extinction timings varied among regions and species. We apply probabilistic sightings methods to 111 high-quality radiocarbon dates (from a pool of 653 dates) on moa remains from natural and archaeological sites to provide a high-resolution spatio-temporal chronology of moa extinction. We interpret this alongside an estimated time for the onset of hunting pressure, obtained by applying the same methods to the most reliable proxies for initial human settlement of New Zealand: coprolites of and seeds gnawed by the commensal Pacific rat ( Rattus exulans ). By comparing local and national extinction times, we discriminate between the point at which hunting stopped (economic extinction) and the total extinction of moa (ca 150 and 200 years after settlement, respectively). Extinction occurred contemporaneously at sites separated by hundreds of kilometres. There was little difference between the extinction times of the smallest (20–50 kg) and largest (200+ kg) moa species. Our results demonstrate how rapidly megafauna were exterminated from even large, topographically- and ecologically-diverse islands such as New Zealand, and highlight the fragility of such ecosystems in the face of human impacts. [ABSTRACT FROM AUTHOR]

Understanding the mechanisms underlying population declines is critical for preventing the extinction of endangered populations. Positive feedbacks can hasten the process of collapse and create an ‘extinction vortex,’ particularly in small, isolated populations. We provide a case study of a male-biased sex ratio creating the conditions for extinction in a natural population of tuatara (Sphenodon punctatus) on North Brother Island in the Cook Strait of New Zealand. We combine data from long term mark-recapture surveys, updated model estimates of hatchling sex ratio, and population viability modeling to measure the impacts of sex ratio skew. Results from the mark-recapture surveys show an increasing decline in the percentage of females in the adult tuatara population. Our monitoring reveals compounding impacts on female fitness through reductions in female body condition, fecundity, and survival as the male-bias in the population has increased. Additionally, we find that current nest temperatures are likely to result in more male than female hatchlings, owing to the pattern of temperature-dependent sex determination in tuatara where males hatch at warmer temperatures. Anthropogenic climate change worsens the situation for this isolated population, as projected temperature increases for New Zealand are expected to further skew the hatchling sex ratio towards males. Population viability models predict that without management intervention or an evolutionary response, the population will ultimately become entirely comprised of males and functionally extinct. Our study demonstrates that sex ratio bias can be an underappreciated threat to population viability, particularly in populations of long-lived organisms that appear numerically stable. [ABSTRACT FROM AUTHOR]

This essay explores how the scientific community interpreted the discoveries of extinct giant birds during the mid-nineteenth century on the islands of New Zealand and Madagascar. It argues that the Aepyornis of Madagascar was understood through the moa of New Zealand because of the rise of global networks and theories. Indeed, their global connections made giant birds a sensation among the scientific community and together forged theories and associations not possible in isolation. In this way, this paper argues for a closer look at how the creation of science emerged from a world framework that involved multiple sites of discovery and interpretation that continually influenced and reshaped scientific theories. It also stresses the importance of local naturalists in participating in this global exchange of knowledge. [ABSTRACT FROM PUBLISHER]

Highlights: [•] Understanding the factors that determine extinction risk is vital for effective conservation. [•] Relative to other vertebrate groups, extinction risk has rarely been examined in reptiles. [•] We conduct the most comprehensive study of extinction risk within a reptile group. [•] Body size, geographic range size and habitat specialization were the strongest predictors of extinction risk. [•] We place our results in context with studies on extinction risk in other vertebrate groups. [ABSTRACT FROM AUTHOR]

Effective sampling and detection plays an important role in the surveillance and management of invasive species. Invasive ants are prime candidates for imperfect detection because of their small size, cryptic nature and also because of their strong association with human transportation around the globe. We examined site occupancy, colonization-extirpation dynamics and detection probability of Argentine ant populations in the Auckland region of New Zealand. Comparison of 175 sites from 2002 to 2007 shows the dynamic nature of Argentine ants, with an extirpation rate of 33% and a colonization rate of 8%. Baited vials gave relatively poor detection for Argentine ants, despite repeated sampling. If Argentine ants were present at a location, their probability of detection using baited vials was, on average, only P = 0.55 (±SE = 0.04). However, this probability depended on the duration that baited vials were left out. Detectability was highest for vials set out for three (P = 0.52-0.75) or 6 h (P = 0.53-0.82). Detection probability for visual searching was 0.895. We use these data to suggest improvements in the design of surveys for Argentine ants. Research on detection theory and its applications for surveillance and eradication is a major gap for invasive ants. [ABSTRACT FROM AUTHOR]

Background: Analysis of ancient DNA has provided invaluable information on past ecologies, ancient populations, and extinct species. We used a short snippet of highly variable mitochondrial control region sequence from New Zealand's moa to characterise a large number of bones previously intractable to DNA analysis as well as bone fragments from swamps to gain information about the haplotype diversity and phylogeography that existed in five moa species. Methodology/Principal Findings: By targeting such 'snippets', we show that moa populations differed substantially in geographic structure that is likely to be related to population mobility and history. We show that populations of Pachyornis geranoides, Dinornis novaezealandiae, and Dinornis robustus were highly structured and some appear to have occupied the same geographic location for hundreds of thousands of years. In contrast, populations of the moa Anomalopteryx didiformis and Euryapteryx curtus were widespread, with specific populations of the latter occupying both the North and South Islands of New Zealand. We further show that for a specific area, in this case a North Island swamp, complete haplotype diversity and even sex can be recovered from collections of small, often discarded, bone fragments. Conclusions/Significance: Short highly variable mitochondrial 'snippets' allow successful typing of environmentally damaged and fragmented skeletal material, and can provide useful information about ancient population diversity and structure without the need to sample valuable, whole bones often held by museums. [ABSTRACT FROM AUTHOR]

Predicting future species extinctions from patterns of past extinctions or current threat status relies on the assumption that the taxonomic and biological selectivity of extinction is consistent through time. If the driving forces of extinction change through time, this assumption may be unrealistic. Testing the consistency of extinction patterns between the past and the present has been difficult, because the phylogenetically explicit methods used to model present-day extinction risk typically cannot be applied to the data from the fossil record. However, the detailed historical and fossil records of the New Zealand avifauna provide a unique opportunity to reconstruct a complete, large faunal assemblage for different periods in the past. Using the first complete phylogeny of all known native New Zealand bird species, both extant and extinct, we show how the taxonomic and phylogenetic selectivity of extinction, and biological correlates of extinction, change from the pre-human period through Polynesian and European occupation, to the present. These changes can be explained both by changes in primary threatening processes, and by the operation of extinction filter effects. The variable patterns of extinction through time may confound attempts to identify risk factors that apply across time periods, and to infer future species declines from past extinction patterns and current threat status. [ABSTRACT FROM AUTHOR]

Birds have long fascinated scientists and travellers, so their distribution and abundance through time have been better documented than those of other organisms. Many bird species are known to have gone extinct, but information on subspecies extinctions has never been synthesised comprehensively. We reviewed the timing, spatial patterns, trends and causes of avian extinctions on a global scale, identifying 279 ultrataxa (141 monotypic species and 138 subspecies of th polytypic species) that have gone extinct since 1500. Species extinctions peaked in the early 20 century, then fell until the th mid 20 century, and have subsequently accelerated. However, extinctions of ultrataxa peaked in the second half of the 20th century. This trend reflects a consistent decline in the rate of extinctions on islands since the beginning of the 20th century, but an acceleration in the extinction rate on continents. Most losses (78.7% of species and 63.0% of subspecies) occurred on oceanic islands. Geographic foci of extinctions include the Hawaiian Islands (36 taxa), mainland Australia and islands (29 taxa), the Mascarene Islands (27 taxa), New Zealand (22 taxa) and French Polynesia (19 taxa). The major proximate drivers of extinction for both species and subspecies are invasive alien species (58.2% and 50.7% of species and subspecies, respectively), hunting (52.4% and 18.8%) and agriculture, including non-timber crops and livestock farming (14.9% and 31.9%). In general, the distribution and drivers of subspecific extinctions are similar to those for species extinctions. However, our finding that, when subspecies are considered, the extinction rate has accelerated in recent decades is both novel and alarming. [ABSTRACT FROM AUTHOR]

Four British bumblebee species ( Bombus terrestris, Bombus hortorum, Bombus ruderatus and Bombus subterraneus) became established in New Zealand following their introduction at the turn of the last century. Of these, two remain common in the United Kingdom ( B. terrestris and B. hortorum), whilst two ( B. ruderatus and B. subterraneus) have undergone marked declines, the latter being declared extinct in 2000. The presence of these bumblebees in New Zealand provides an unique system in which four related species have been isolated from their source population for over 100 years, providing a rare opportunity to examine the impacts of an initial bottleneck and introduction to a novel environment on their population genetics. We used microsatellite markers to compare modern populations of B. terrestris, B. hortorum and B. ruderatus in the United Kingdom and New Zealand and to compare museum specimens of British B. subterraneus with the current New Zealand population. We used approximate Bayesian computation to estimate demographic parameters of the introduction history, notably to estimate the number of founders involved in the initial introduction. Species-specific patterns derived from genetic analysis were consistent with the predictions based on the presumed history of these populations; demographic events have left a marked genetic signature on all four species. Approximate Bayesian analyses suggest that the New Zealand population of B. subterraneus may have been founded by as few as two individuals, giving rise to low genetic diversity and marked genetic divergence from the (now extinct) UK population. [ABSTRACT FROM AUTHOR]

Abstract: Spores of the dung-fungi Sporormiella are routinely used as a proxy for past megaherbivore biomass and to pinpoint the timing of extinctions. Further ecological insight can also be gained into the impacts that followed initial human arrival in a region through correlation of spore abundance with other proxies (e.g. pollen, charcoal). Currently, the use of Sporormiella as a palaeoecological proxy has been restricted to landmasses where large-herbivore guilds are dominated by mammals. Here, we use New Zealand as a case study to show that the method can also be applied effectively to islands dominated by large avian herbivores. We examine 44 dung samples from 7 localities to show that Sporormiella spores were widely distributed in the dung of endemic avian herbivores (South Island takahe (Porphyrio hochstetteri), kakapo (Strigops habroptilus), and several species of extinct moa, identified by ancient DNA analysis). In addition, we show that Sporormiella spores in a forest soil core from the Murchison Mountains, South Island, accurately trace the post-settlement decline of native avian herbivores, and combined with high-resolution radiocarbon dating reveal severely reduced local herbivore populations by the late 17th Century AD. The spores also trace the subsequent spread of Red deer (Cervus elaphus) introduced to the area in the early 20th Century AD. Our results suggest Sporormiella spores may provide a useful new tool for examining extinctions on numerous islands where terrestrial herbivore guilds were dominated by birds or reptiles. Our findings also highlight the need to consider entire herbivore communities (including birds and reptiles) when examining Late Pleistocene continental Sporormiella records, where the focus has often been tracing the decline of populations of large mammals. [Copyright &y& Elsevier]

Abstract: This research combines automated Geographical Information Systems (GIS) and iterative logistic regression scripting to data-mine for terrain variables that predict stoat (Mustela erminea) visitation to tracking-stations in a New Zealand indigenous forest and explore the impact of spatial analysis scale on modelling outcomes. Variables such as curvature and density of tracks are dependent on the scale of the analysis window used to compute the values. With automated GIS analysis it is possible to derive a large number of terrain parameters that vary in computational scale. It is common for analysts to make nominal choices regarding the size and type of analysis windows when calculating these derived variables, without testing the statistical validity of that choice. Stoats are a significant pest in New Zealand and threaten extinction for a number of vulnerable native species. Field data on stoat activity, based on footprint tracking tunnels, were used to develop an Akaike Information Criterion (AIC) optimised predictive model applying stepwise model selection. Once the optimal model was determined, the sensitivity of the model to different terrain parameters was tested by systematically substituting each variable and calculating the difference this made to the model equation. The most dominant terrain predictors influencing stoat visitation were proximity to tracks, altitude, northerly and easterly aspect, mean curvature, and topographical position and slope. Proximity to tracks and mean curvature were the most sensitive variables to analysis scale. This paper demonstrates the importance of considering scale in developing predictive models and the need to test many ecologically sensible analysis scales in order to find the best predictive variables. The paper concludes that GIS-based spatial data extraction, combined with automated statistical data mining methods, has an important role in developing accurate animal activity models. [Copyright &y& Elsevier]

Abstract: A brief appraisal of marine fossils from high latitudes and episodically cold climate especially in east Australia and New Zealand during Late Palaeozoic and Early Mesozoic times shows patterns of evolution and survival that differ from those adduced for the palaeotropics and Northern Hemisphere. Examples taken from amongst phyla Scyphozoa, Bryozoa, Brachiopoda and Classes Bivalvia and Class Cephalopoda suggest these attributes: [1.] Evolution and demise of species and genera proceeded at a rate close to that known for palaeotropical and Northern Hemisphere macro-invertebrates, but involved fewer families and orders. [2.] Possibly, intraspecific variation was greater amongst southern palaeohemisphere Permian species than in those of the Permian palaeotropics. [3.] There was no proven diminution of life at the end of the Guadalupian (Middle Permian) at southern high latitudes, where however the fossil record is meagre for this interval. Younger Wuchiapingian and Changhsingian faunas were moderately diverse. [4.] There is no evidence for a high latitude Southern Hemisphere anoxic event in the Early Triassic despite claims of a world-wide anoxic interval. Nor has any substantial volcanic eruption or bolide impact left any marked traces in the sedimentary record. [5.] As a consequence, some major groups such as Bryozoa and Conulariida (Staurozoa) survived the end-Permian extinction shock in the Southern Hemisphere. [6.] Other major groups appear to have survived better in the south than in the north, notably, mollusc Bivalvia and Cephalopoda. It therefore appears likely that Triassic seas were restocked substantially from the Southern Hemisphere and that the Permian extinction shock was asymmetric with respect to latitudes in its distribution and affect. [ABSTRACT FROM AUTHOR]

Mainstream conservation has been long dominated globally by the protected area paradigm. This approach has been widely challenged in recent years, and new conservation initiatives have emerged. The situation is mirrored in New Zealand, where ongoing biodiversity loss has prompted reappraisal. Within this context, we highlight the plight of kiwi, focusing on Northland and efforts there to (re)make space for this iconic bird which is at risk of extinction. While the state has primarily responded by fortifying 'islands' on public conservation land, Far North communities are working in a variety of ways and localities, both within and beyond 'the fortress', to secure a future for the 'people's bird'. [ABSTRACT FROM AUTHOR]

Abstract: Ancient DNA was isolated from the bones of 267 individuals of the extinct New Zealand moa (Aves: Dinornithiformes) from two late Holocene deposits [Pyramid Valley (PV) and Bell Hill Vineyard (BHV)] located 5.7km apart in North Canterbury, South Island. The two sites’ combined fossil record cover the last 3000years of pre-human New Zealand and mitochondrial DNA confirmed that four species (Dinornis robustus, Euryapteryx curtus, Emeus crassus, and Pachyornis elephantopus) were sympatric in the region. However, the relative species compositions in the two deposits differed significantly with D. robustus and E. crassus being most abundant at PV while E. curtus outnumbered the other three moa taxa combined at BHV. A subsample of 227 individuals had sufficient nuclear DNA preservation to warrant the use of molecular sexing techniques, and the analyses uncovered a remarkable excess of females in both deposits with an overall male to female ratio of 1:5.1. Among juveniles of E. curtus, the only species which was represented by a substantial fraction of juveniles, the sex ratio was not skewed (10 ♂, 10 ♀), suggesting that the observed imbalance arose as a result of differential mortality during maturation. Surprisingly, sex ratios proved significantly different between sites with a 1:2.2 ratio at BHV (n =90) and 1:14.2 at PV (n =137). Given the mobility of large ratites, and the proximity of the two fossil assemblages in space and time, these differences in taxonomic and gender composition indicate that moa biology and the local environment have affected the fossil representation dramatically and several possible explanations are offered. Apart from adding to our understanding of moa biology, these discoveries reinforce the need for caution when basing interpretation of the fossil record on material from a single site. [Copyright &y& Elsevier]

The ratite moa (Ayes: Dinornithiformes) were a speciose group of massive graviportal avian herbivores that dominated the New Zealand (NZ) ecosystem until their extinction ≈600 years ago. The phylogeny and evolutionary history of this morphologically diverse order has remained controversial since their initial description in 1839. We synthesize mitochondrial phylogenetic information from 263 subfossil moa specimens from across NZ with morphological, ecological, and new geological data to create the first comprehensive phylogeny, taxonomy, and evolutionary timeframe for all of the species of an extinct order. We also present an important new geological/paleogeographical model of late Cenozoic NZ. which suggests that terrestrial biota on the North and South Island landmasses were isolated for most of the past 20-30 Ma. The data reveal that the patterns of genetic diversity within and between different moa clades reflect a complex history following a major marine transgression in the Oligocene, affected by marine barriers, tectonic activity, and glacial cycles. Surprisingly, the remarkable morphological radiation of moa appears to have occurred much more recently than previous early Miocene (Ca. 15 Ma) estimates, and was coincident with the accelerated uplift of the Southern Alps just Ca. 5-8.5 Ma. Together with recent fossil evidence, these data suggest that the recent evolutionary history of nearly all of the iconic NZ terrestrial biota occurred principally on just the South Island. [ABSTRACT FROM AUTHOR]

Abstract: Previous estimates of molluscan biodiversity during the Neogene in New Zealand have revealed a pattern of significant diversity decline during the latest Miocene. This study uses an occurrence-based dataset (derived from published literature) to examine this pattern in further detail with both traditional synoptic measures and subsequent sampling standardization. Synoptic analyses of regional-scale data reveal diversity trajectories similar to those previously established, and rarefaction techniques demonstrate that the inferred pattern of Late Miocene diversity decline and Early Pliocene rebound is only somewhat biased by variations in sampling intensity. The pattern is also affected by temporal variations in the preservation of shelf paleoenvironments, with representation of highly diverse shallow-water facies varying considerably between biostratigraphic stages. The sampling and corresponding synoptic genus richness of biogeographic areas within the New Zealand region is also uneven. Within a single sedimentary basin sampled at high temporal resolution (Wanganui Basin), new data suggest that Late Miocene faunas were as diverse as those of the Early Pliocene, contrasting with the pattern of diversity decrease and subsequent increase observed at the regional spatial scale in prior studies. However, an ecological analysis of the new data demonstrates that turnover and restructuring of benthic communities did take place at the end of the Late Miocene. These findings suggest that spatial scale and temporal resolution are important considerations in determining the magnitude of diversity and ecological change observed in paleontologic studies. Contemporaneous biodiversity may not be similarly expressed at varying spatial or temporal scales in the fossil record. Rather, regional patterns of diversity change are governed by a complex interplay of not only large-scale environmental factors (e.g. temperature control), but also independent basin-scale processes (e.g. basin subsidence) and local sampling intensity. [Copyright &y& Elsevier]

Abstract: The discovery in New Zealand of Late Holocene deposits of coprolites from extinct avian megaherbivores has provided a unique opportunity to gain a detailed insight into the ecology of these birds across ecologically diverse habitats. Macrofossil analysis of 116 coprolites of the giant ratite moa (Aves, Dinornithiformes) reveals a diverse diet of herbs and low shrubs in both semi-arid and high rainfall ecological zones, overturning previous models of moa as dominantly browsers of trees and shrubs. Ancient DNA analysis identified coprolites from four moa species (South Island giant moa, Dinornis robustus; upland moa, Megalapteryx didinus; heavy-footed moa, Pachyornis elephantopus and stout-legged moa, Euryapteryx gravis), revealing a larger dietary variation between habitat types than between species. The new data confirm that moa fed on a variety of endemic plant taxa with unusual growth forms previously suggested to have co-evolved with moa. Lastly, the feeding ecologies of moa are shown to be widely different to introduced mammalian herbivores. [Copyright &y& Elsevier]

Abstract: Australia has been cited as a weak link in anthropogenic models of megafauna extinction, but recent work suggests instead that the evidence for rapid extinction shortly after human arrival is robust. The global model is revisited, based on the contention that late Pleistocene megafauna extinctions took place rapidly on islands, and some islands (such as Australia and the Americas) are much larger than others. Modern dating methods are increasingly able to refine chronologies, and careful scrutiny suggests that hundreds of dates should be deleted from archives. An updated summary of results from New Zealand, North America and Australia is presented, with a brief discussion on why temperate refugia offering protection from climate change ultimately did not work, strongly supporting the global extinction hypothesis pioneered by Paul Martin. [Copyright &y& Elsevier]

The introduction of predatory mammals to oceanic islands has led to the extinction of many endemic birds. Although introduced predators should favour changes that reduce predation risk in surviving bird species, the ability of island birds to respond to such novel changes remains unstudied. We tested whether novel predation risk imposed by introduced mammalian predators has altered the parental behaviour of the endemic New Zealand bellbird (Anthornis melanura). We examined parental behaviour of bellbirds at three woodland sites in New Zealand that differed in predation risk: 1) a mainland site with exotic predators present (high predation risk), 2) a mainland site with exotic predators experimentally removed (low risk recently) and, 3) an off-shore island where exotic predators were never introduced (low risk always). We also compared parental behaviour of bellbirds with two closely related Tasmanian honeyeaters (Phylidonyris spp.) that evolved with native nest predators (high risk always). Increased nest predation risk has been postulated to favour reduced parental activity, and we tested whether island bellbirds responded to variation in predation risk. We found that females spent more time on the nest per incubating bout with increased risk of predation, a strategy that minimised activity at the nest during incubation. Parental activity during the nestling period, measured as number of feeding visits/hr, also decreased with increasing nest predation risk across sites, and was lowest among the honeyeaters in Tasmania that evolved with native predators. These results demonstrate that some island birds are able to respond to increased risk of predation by novel predators in ways that appear adaptive. We suggest that conservation efforts may be more effective if they take advantage of the ability of island birds to respond to novel predators, especially when the elimination of exotic predators is not possible. [ABSTRACT FROM AUTHOR]

There has been considerable recent interest in how human-induced species loss affects community and ecosystem properties. These effects are particularly apparent when a commercially valuable species is harvested from an ecosystem, such as occurs through single-tree harvesting or selective logging of desired timber species in natural forests. In New Zealand mixed-species rain forests, single-tree harvesting of the emergent gymnosperm Dacrydium cupressinum, or rimu, has been widespread. This harvesting has been contentious in part because of possible ecological impacts of Dacrydium removal on the remainder of the forest, but many of these effects remain unexplored. We identified an area where an unintended 40-year "removal experiment" had been set up that involved selective extraction of individual Dacrydium trees. We measured aboveground and belowground variables at set distances from both individual live trees and stumps of trees harvested 40 years ago. Live trees had effects both above and below ground by affecting diversity and cover of several components of the vegetation (usually negatively), promoting soil C sequestration, enhancing ratios of soil C:P and N:P, and affecting community structure of soil microflora. These effects extended to 8 m from the tree base and were likely caused by poor-quality litter and humus produced by the trees. Measurements for the stumps revealed strong legacy effects of prior presence of trees on some properties (e.g., cover by understory herbs and ferns, soil C sequestration, soil C:P and N:P ratios), but not others (e.g., soil fungal biomass, soil N concentration). These results suggest that the legacy of prior presence of Dacrydium may remain for several decades or centuries, and certainly well over 40 years. They also demonstrate that, while large Dacrydium individuals (and their removal) may have important effects in their immediate proximity, within a forest, these effects should only be important in localized patches containing high densities of large trees. Finally, this study emphasizes that deliberate extraction of a particular tree species from a forest can exert influences both above and below ground if the removed species has a different functional role than that of the other plant species present. [ABSTRACT FROM AUTHOR]

In the time between speciation and extinction, a species' ecological and biogeographic footprint—its occupancy—will vary in response to macroecological drivers and historical contingencies. Despite their importance for understanding macroecological processes, general patterns of long-term species occupancy remain largely unknown. We documented the occupancy histories of Cenozoic marine mollusks from New Zealand. For both genera and species, these show a distinct pattern of increase to relatively short-lived peak occupancy at mid-duration, followed by a decline toward extinction. Thus, species at greatest risk for extinction are those that have already been in decline for a substantial period of time. This pattern of protracted rise and fall stands in contrast to that of incumbency, insofar as species show no general tendency to stay near maximal occupancy once established. [ABSTRACT FROM AUTHOR]

Habitat fragmentation causes extinction of local animal populations by decreasing the amount of viable “core” habitat area and increasing edge effects. It is widely accepted that larger fragments make better nature reserves because core-dwelling species have a larger amount of suitable habitat. Nevertheless, fragments in real landscapes have complex, irregular shapes. We modeled the population sizes of species that have a representative range of preferences for or aversions to habitat edges at five spatial scales (within 10, 32, 100, 320, and 1000 m of an edge) in a nation-wide analysis of forest remnants in New Zealand. We hypothesized that the irregular shapes of fragments in real landscapes should generate statistically significant correlations between population density and fragment area, purely as a “geometric” effect of varying species responses to the distribution of edge habitat. Irregularly shaped fragments consistently reduced the population size of core-dwelling species by 10–100%, depending on the scale over which species responded to habitat edges. Moreover, core populations within individual fragments were spatially discontinuous, containing multiple, disjunct populations that inhabited small spatial areas and had reduced population size. The geometric effect was highly nonlinear and depended on the range of fragment sizes sampled and the scale at which species responded to habitat edges. Fragment shape played a strong role in determining population size in fragmented landscapes; thus, habitat restoration efforts may be more effective if they focus on connecting disjunct cores rather than isolated fragments. [ABSTRACT FROM AUTHOR]

Pest control is a key activity undertaken to conserve threatened and declining species. Although bioeconomic analysis has been used to contrast the relative efficiency of control strategies where pests affect economic resources, the same approaches have been adopted rarely in conservation settings. The Mohua ( Mohoua ochrocephala ) is an insectivorous passerine indigenous to beech ( Nothofagus spp.) forests in New Zealand's south island. Mohua have undergone a 75% range contraction since stoats ( Mustela erminea ) (which prey on nests and nesting females) were introduced to the south island in the late 1800s. Mohua nests are particularly vulnerable when stoat abundance increases in response to eruptions in the density of introduced house mice ( Mus musculus ), which in turn respond to semiperiodic (4–6 year) mass seeding (masting) of beech trees. Controlling stoats only when their abundance poses a threat to Mohua fledging success would theoretically maximize the efficiency with which Mohua are protected. To better synchronize stoat control with periods of high stoat density, control could be initiated according to (1) time since last control, (2) beech seedfall, (3) mouse abundance, or (4) stoat abundance. Monitoring the three environmental cues, however, incurs costs that should be taken into account when considering their relative efficiency. I derived an empirically based stochastic model that links sequential change in beech seedfall, mouse, and stoat abundance to a simple demographic model for Mohua. I used the model to contrast the relative cost-efficiency of achieving conservation outcomes for Mohua (specified in a quasi-extinction framework), initiating stoat control according to these cues. The use of environmental cues reduced the frequency with which stoat control had to be undertaken to achieve Mohua conservation outcomes by more than 50%. For some cues, however, the costs of monitoring outweighed the savings that could be achieved through reduced frequency of stoat control. The interplay between costs of monitoring environmental cues and the frequency with which stoat control had to be undertaken meant that the most efficient strategy was dependent on the conservation outcome specified for Mohua. My results demonstrate the utility of bioeconomic analysis in formulation of pest management strategies to achieve conservation outcomes. [ABSTRACT FROM AUTHOR]

1. Nucleotide sequences of a 280 base pair region of the cytochrome b gene were used to assess genetic diversity and to infer population histories in the New Zealand mayfly Acanthophlebia cruentata. 2. A hierarchial examination of populations from 19 streams at different spatial scales in the central and northern North Island of New Zealand found 34 haplotypes. A common haplotype was found in all central region streams and unique haplotypes in northern streams. Several central streams had region specific haplotypes with genetically differentiated populations at the 70–100 km scale. 3. Haplotype diversity was high (0.53–0.8) at most sites, but low (0–0.22) in some central sites. amova analyses found significant genetic diversity among regions (69%) and among catchments (58%). Most population pairwise FST tests were significant, with non-significant pairwise tests among sites in the central region and pairs of sites between neighbouring streams. 4. The levels of sequence divergence are interpreted as the result of Pleistocene divergence in multiple refugia, leading to the evolution of regionally unique haplotypes. The low diversity in some central region populations may result from recent colonisation following local extinctions, associated with volcanic events. [ABSTRACT FROM AUTHOR]

Populations established with a small number of founders are thought to have a high risk of extinction due to allee effects, demographic stochasticity, inbreeding and reduced genetic variation. We tested whether the initial number of birds released was related to persistence in reintroductions of saddlebacks (Philesturnus carunculatus) and robins (Petroica australis) to New Zealand offshore islands. Data were analysed for 31 populations that had been observed for at least 3 years since reintroductions. The numbers released ranged from 5–188. Most of the populations (26) survived and grew, including five from less than 15 founders, and four out of the five extinctions were attributable to introduced mammalian predators. The number of individuals released did not significantly affect extinction probability. The ability of these small releases to establish populations can be attributed to the closed nature of the islands (allowing birds to find mates), low mortality rates following release and high growth rates at low density. Stochastic simulation models based on data from two reintroduced populations suggested that populations with four founders (two male, two female) would have a negligible chance of extinction through demographic stochasticity and would be able to grow even if there were high rates of egg failure through inbreeding. [ABSTRACT FROM AUTHOR]