Nicola Mitchell

Nicola Mitchell
University of Western Australia | UWA · School of Biological Sciences

PhD University of Adelaide

About

118
Publications
42,404
Reads
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Introduction
Our lab focuses on anticipating the impacts of environmental change on threatened species. Currently we work with freshwater turtles, sea turtles, skinks, frogs and mammals, employing skills in physiological ecology, genetics and environmental modelling to investigate the capacity of species to adapt to climate change. Pre-emptive conservation strategies such as assisted colonisation and targeted gene flow are a major research interest.
Additional affiliations
March 2005 - present
University of Western Australia
Position
  • Professor (Associate)
October 2000 - November 2002
Victoria University of Wellington
Position
  • Research Associate
Education
February 1997 - September 2000
University of Adelaide
Field of study
  • Environmental Biology

Publications

Publications (118)
Article
Full-text available
How will climate change affect species' reproduction and subsequent survival? In many egg-laying reptiles, the sex of offspring is determined by the temperature experienced during a critical period of embryonic development (temperature-dependent sex determination, TSD). Increasing air temperatures are likely to skew offspring sex ratios in the abse...
Article
Full-text available
Assisted colonization-the deliberate translocation of species from unsuitable to suitable regions-is a controversial management tool that aims to prevent the extinction of populations that are unable to migrate in response to climate change or to survive in situ. The identification of suitable translocation sites is therefore a pressing issue. Corr...
Article
Full-text available
The capacity of species to respond adaptively to warming temperatures will be key to their survival in the Anthropocene. The embryos of egg-laying species such as sea turtles have limited behavioural means for avoiding high nest temperatures, and responses at the physiological level may be critical to coping with predicted global temperature increa...
Article
Intra‐specific variation in the ability of individuals to tolerate environmental perturbations is often neglected when considering the impacts of climate change. Yet this information is potentially crucial for mitigating deleterious effects of climate change on threatened species. Here we assessed patterns of intra‐specific variation in desiccation...
Article
Environmental conditions experienced by animals constrain their energy acquisition and its subsequent allocation to growth and reproduction, which ultimately contributes to population dynamics. Understanding how environmental conditions affect these physiological processes is therefore important for predicting how threatened species will respond to...
Article
Full-text available
In the face of the current global extinction crisis, it is critical we give conservation management strategies the best chance of success. Australia is not exempt from global trends with currently the world’s greatest mammal extinction rate (~ 1 per 8 years). Many more are threatened including the dibbler ( Parantechinus apicalis ) whose remnant ra...
Article
Full-text available
Comprehensive assessments of species’ extinction risks have documented the extinction crisis and underpinned strategies for reducing those risks. Global assessments reveal that, among tetrapods, 40.7% of amphibians, 25.4% of mammals and 13.6% of birds are threatened with extinction. Because global assessments have been lacking, reptiles have been o...
Article
Full-text available
Comprehensive assessments of species’ extinction risks have documented the extinction crisis and underpinned strategies for reducing those risks. Global assessments reveal that, among tetrapods, 40.7% of amphibians, 25.4% of mammals and 13.6% of birds are threatened with extinction. Because global assessments have been lacking, reptiles have been o...
Poster
Full-text available
The Eastern Pacific Leatherback Population (EPLB) is considered critically endangered and current model projections predict functional extinction by 2080. The known key threats are; primarily, fisheries bycatch of adult and sub-adults, and secondarily, reduced hatchling output from nest loss. The Laúd OPO network has developed an action plan to att...
Poster
Full-text available
The East Pacific subpopulation of leatherback sea turtles (Dermochelys coriacea) is Critically Endangered as a result of historic unsustainable egg harvest and ongoing fisheries bycatch. Despite extensive and sustained conservation efforts, the most optimistic prediction is that the subpopulation will be functionally extinct by 2080. While populati...
Article
Full-text available
Aim The incidence of major fires is increasing globally, creating extraordinary challenges for governments, managers and conservation scientists. In 2019–2020, Australia experienced precedent‐setting fires that burned over several months, affecting seven states and territories and causing massive biodiversity loss. Whilst the fires were still burni...
Article
Full-text available
After environmental disasters, species with large population losses may need urgent protection to prevent extinction and support recovery. Following the 2019–2020 Australian megafires, we estimated population losses and recovery in fire‐affected fauna, to inform conservation status assessments and management. Temperate and subtropical Australia. 20...
Article
Full-text available
Background Mammals, globally, are facing population declines. Strategies increasingly employed to recover threatened mammal populations include protecting populations inside predator-free havens, and translocating animals from one site to another, or from a captive breeding program. These approaches can expose predator-naïve animals to predators th...
Article
Full-text available
Targeted gene flow (TGF) could bolster the adaptive potential of isolated populations threatened by climate change, but could also lead to outbreeding depression. Here, we explore these possibilities by creating mixed- and within-population crosses in a terrestrial-breeding frog species threatened by a drying climate. We reared embryos of the crawl...
Article
Amphibian breeding is often linked to environmental cues. Given accelerating global climate change and habitat alteration, it is important to understand how environmental changes may affect male calling activity, the necessary precursor to mating. Here, we investigate the calling phenology and activity of Geocrinia alba, a critically endangered ter...
Article
Nest microclimates influence embryonic development and survival in many lineages, including reptiles with temperature-dependent sex determination. These microclimates are dependent on physical drivers and biological processes, such as embryonic metabolism, that generate heat. The flatback turtle (Natator depressus) has among the largest hatchlings...
Article
Full-text available
More than a third of the world’s amphibian species are listed as Threatened or Extinct, with a recent assessment identifying 45 Australian frogs (18.4% of the currently recognised species) as ‘Threatened’ based on IUCN criteria. We applied structured expert elicitation to 26 frogs assessed as Critically Endangered and Endangered to estimate their p...
Technical Report
Full-text available
In July 2020, the Conservation Planning Specialist Group (CPSG) of the International Union for Conservation of Nature (IUCN) Species Survival Commission (SSC) was enlisted by the international non-profit sea turtle conservation organization, Upwell, to design and facilitate a two-step decision making process to inform conservation efforts for the C...
Article
Full-text available
Drier and hotter conditions caused by climate change threaten species that exist close to their physiological limits, as well as those with limited ability to move. Habitat specialists may also be particularly vulnerable if they have specific abiotic requirements. Here we assess whether thermal and hydric constraints can explain the highly restrict...
Article
Our knowledge of the conservation status of reptiles, the most diverse class of terrestrial vertebrates, has improved dramatically over the past decade, but still lags behind that of the other tetrapod groups. Here, we conduct the first comprehensive evaluation (~92% of the world's ~1714 described species) of the conservation 1 Joint senior authors...
Article
Full-text available
The blue-tailed skink (Cryptoblepharus egeriae) is endemic to Christmas Island but underwent rapid population declines in the 1990s and 2000s and was listed as Extinct in the Wild in 2017. As invasive giant centipedes (Scolependra subspinipes) were implicated as a cause of a failed reintroduction of captive bred skinks into a fenced enclosure, we u...
Article
Full-text available
Until recently, the reptile fauna of Christmas Island in the Indian Ocean comprised five endemic species (two skinks, two geckos, and one snake) and one native, non-endemic skink. Four of these species were common and widespread until at least 1979, but by 2012 had disappeared from the wild. During the years of decline, little research was undertak...
Article
Full-text available
Defining species habitat requirements is essential for effective conservation management through revealing agents of population decline and identifying critical habitat for conservation actions, such as translocations. Here we studied the habitat-associations of two threatened terrestrial-breeding frog species from southwestern Australia, Geocrinia...
Article
Full-text available
In the original publication of the article, Figure 1 was published incorrectly. The correct figure is given below. The original article has been corrected.
Article
Full-text available
Many Australian mammal species now only occur on islands and fenced mainland havens free from invasive predators. The range of one species, the banded hare-wallaby (Lagostrophus fasciatus), had contracted to two offshore islands in Western Australia. To improve survival, four conservation translocations have been attempted with mixed success, and a...
Article
Ejaculate traits vary extensively among individuals and species, but little is known about their variation among populations of the same species. Here, we investigated patterns of intraspecific variation in male reproductive investment in the terrestrial-breeding frog Pseudophryne guentheri. Like most anurans, breeding activity in P. guentheri is c...
Article
Full-text available
Species with restricted ranges and long generation times are vulnerable to climate change due to limited opportunity to disperse or adapt. Australia’s rarest reptile, the western swamp turtle Pseudemydura umbrina , persists naturally in only one seasonal swamp that holds water in the Austral winter and spring. A marked reduction in winter rainfall...
Article
Full-text available
Just as organisms do not passively exist in their environment, developing sea turtle embryos affect their own incubation microclimate by producing metabolic heat and other waste products. This metabolic heat ultimately contributes to successful development, but it is unclear how it influences embryonic traits such as hatchling sex, and whether tren...
Article
Full-text available
Australia hosts approximately 10% of the world's reptile species, the largest number of any country. Despite this and evidence of widespread decline, the first comprehensive assessment of the conservation status of Australian terrestrial squamates (snakes and lizards) was undertaken only recently. Here we apply structured expert elicitation to the...
Article
Both the development rate and sex of sea turtle embryos depend on incubation temperature, as all species of sea turtle are ectotherms and show temperature‐dependent sex determination (TSD). Theory predicts that selection should act on populations to optimise developmental times and primary sex ratios. In this study, we use a consistent methodology...
Article
The continual development of ecological models and availability of high-resolution gridded climate surfaces have stimulated studies that link climate variables to functional traits of organisms. A primary constraint of these studies is the ability to reliably predict the microclimate that an organism experiences using macroscale climate inputs. Thi...
Article
Quantifying organismal sensitivity to heat stress provides one means for predicting vulnerability to climate change. Birds are ideal for investigating this approach, as they display quantifiable fitness consequences associated with behavioural and physiological responses to heat stress. We used a recently developed method that examines correlations...
Article
Full-text available
Tropical montane forests (TMFs) are major centers of evolutionary change and harbor many endemic species with small geographic ranges. In this systematic map, we focus on the impacts of anthropogenic habitat degradation on TMFs globally. We first determine how TMF research is distributed across geographic regions, degradation type (i.e., deforestat...
Article
Terrestrial-breeding amphibians are likely to be vulnerable to warming and drying climates, as their embryos require consistent moisture for successful development. Adaptation to environmental change will depend on sufficient genetic variation existing within or between connected populations. Here, we use Single Nucleotide Polymorphism (SNP) data t...
Technical Report
Full-text available
Maintaining mammal populations on havens – whether they are naturally occurring or translocated – has helped to prevent further mammal extinctions, and consolidated protection for other species. These havens fall under the management of many organisations, ranging from local councils, community groups and small private organisations to large non-go...
Technical Report
Full-text available
Many Australian mammal species are highly susceptible to predation by introduced cats and foxes. At least 34 Australian endemic mammal species have been made extinct since 1788, about 10% of Australia's terrestrial fauna, and predation by cats and foxes was a major contribution to most of those extinctions. Maintaining mammal populations on havens...
Article
Full-text available
In the last 30 years, islands and fenced exclosures free of introduced predators (collectively, havens) have become an increasingly used option for protecting Australian mammals imperiled by predation by introduced cats (Felis catus) and foxes (Vulpes vulpes). However, Australia's network of havens is not expanding in a manner that maximizes repres...
Book
Lizards and snakes (squamate reptiles) are the most diverse vertebrate group in Australia, with approximately 1000 described species, representing about 10% of the global squamate diversity. Squamates are a vital part of the Australian ecosystem, but their conservation has been hindered by a lack of knowledge of their diversity, distribution, biolo...
Technical Report
Full-text available
Overview (Chapter 1) The Kimberley coast remains a region of inadequate knowledge to understand the status of regional marine turtle stocks that face multiple contemporary pressures such as climate change, marine debris, coastal development and increasing visitation. Existing knowledge reveals scattered information on the distribution and relative...
Article
Full-text available
The thermal environment of sea turtle embryos has marked effects on many aspects of their development and energetics and has consequences for posthatching stages. Here we incubated Chelonia mydas embryos from Ningaloo Reef in Western Australia at a range of temperatures (27°, 29°, 30°, 31°, 32°, and 30° ± 5°C) to determine development rates and the...
Article
When organisms encounter heterogeneous environments, selection may favor the ability of individuals to tailor their phenotypes to suit the prevailing conditions. Understanding the genetic basis of plastic responses is therefore vital for predicting whether susceptible populations can adapt and persist under new selection pressures. Here, we investi...
Article
The complex life history of sea turtles presents challenges for researchers. These slow-growing, longlived reptiles occupy several habitats throughout their life cycle, including oceanic environments where they are difficult to study. Consequently, much research on sea turtle biology has focussed on the nesting environment. Yet, to effectively mana...
Preprint
Full-text available
Intra-specific variation in the ability of individuals to tolerate environmental perturbations is often neglected when considering the impacts of climate change. Yet this information is potentially crucial for mitigating any deleterious effects of climate change on threatened species. Here we assessed patterns of intra-specific variation in desicca...
Article
Dynamic energy budget (DEB) theory provides a generalised way to quantify how an organism assimilates and utilizes energy throughout its life cycle. Over 800 DEB models have been created to date, typically under the assumption of constant food supply. The Critically Endangered, semi-aquatic western swamp turtle occupies an ephemeral wetland environ...
Article
Full-text available
Climate change is driving a pervasive global redistribution of the planet's species. Species redistribution poses new questions for the study of ecosystems, conservation science and human societies that require a coordinated and integrated approach. Here we review recent progress, key gaps and strategic directions in this nascent research area, emp...
Article
Full-text available
Climate change is driving a pervasive global redistribution of the planet's species. Species redistribution poses new questions for the study of ecosystems, conservation science and human societies that require a coordinated and integrated approach. Here we review recent progress, key gaps and strategic directions in this nascent research area, emp...
Article
Full-text available
Context: Many Australian mammal species are highly susceptible to predation by introduced domestic cats (Felis catus) and European red foxes (Vulpes vulpes). These predators have caused many extinctions and have driven large distributional and population declines for many more species. The serendipitous occurrence of, and deliberate translocations...
Article
Full-text available
Context: Over the last 230 years, the Australian terrestrial mammal fauna has suffered a very high rate of decline and extinction relative to other continents. Predation by the introduced red fox (Vulpes vulpes) and feral cat (Felis catus) is implicated in many of these extinctions, and in the ongoing decline of many extant species. Aims: To assess...
Article
Full-text available
A common feature of many citizen science projects is the collection of data by unpaid contributors with the expectation that the data will be used in research. Here we report a teaching strategy that combined citizen science with inquiry-based learning to offer first year university students an authentic research experience. A six-year partnership...
Data
Microsoft Excel database of responses to quantitative survey questions (Likert scale, yes/no) from 2011–2014. (XLSX)
Data
Demographics (frequency in percentage) of students who completed pre and post surveys in each year of the study. (DOCX)
Data
Intercoder reliability assessment for qualitative analysis, showing the percent agreement and Krippendorf’s alpha values for each theme. (DOCX)
Data
Microsoft Excel database of qualitative responses to survey questions from 2011–2014. (XLSX)
Article
Full-text available
Distributions of Earth’s species are changing at accelerating rates, increasingly driven by human-mediated climate change. Such changes are already altering the composition of ecological communities, but beyond conservation of natural systems, how and why does this matter? We review evidence that climate-driven species redistribution at regional to...
Article
Full-text available
Southwest Australia (SWA) is a global biodiversity hotspot and a centre of diversity and endemism for the Australo-Papuan myobatrachid frogs. Myobatrachus gouldii (the turtle frog) has a highly derived morphology associated with its forward burrowing behaviour, largely subterranean habit, and unusual mode of reproduction. Its sister genera Metacrin...
Data
Representative parsimony phylograms for each of the four nDNA genes sequenced in this study. For each gene one of the 1,000 saved parsimony trees is shown. Branch lengths are indicated for each gene. Myobatrachus gouldii samples are indicated by a black line and other taxa represent outgroup species. (PDF)
Data
Map depicting locations of Myobatrachus gouldii specimens sampled for sequence data and morphology. Sampling gaps can be seen by comparing the ‘Morphology’ and ‘Genotyped’ markers to Western Australian Museum (WAM) locality data, from which the range of M. gouldii is inferred. (DOC)
Data
Phylogeny of 42 Myobatrachus gouldii samples and outgroups based on the combined nd2 and rpl3 data, and their distribution across eastern Australia. Here we show the relationships among the ve clades based on a concatenated RAxML analysis. Numbers beside nodes refer to ML bootstrap support. (PDF)