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Citizen‐science projects focused on ecology and conservation have been growing in popularity in recent years, offering many opportunities for researchers and volunteers alike. Two principal approaches to citizen‐science projects in ecology can be characterized as the data‐first approach and the question‐first approach. Here, we highlight the value of question‐first citizen‐science projects for providing insights into the ecology and management of urban wildlife, using case studies on (1) beneficial insects (pollinators, predators and parasitoids) and (2) possums and gliders in Australian cities and towns. The question‐first approach has many benefits, offering a platform to engage volunteers with the scientific process and the broader context of an ecological or conservation problem, while also connecting them with their local environment. Identifying the questions to be addressed in a citizen‐science project ahead of data collection allows for co‐design and stronger collaboration with volunteers, community groups, local experts, and landscape managers. Question‐first citizen science can also provide valuable ecological data that extend substantially beyond presence‐only records, including presence‐absence data collected via timed surveys and information on animal behavior and interspecific interactions. However, establishing and maintaining question‐first citizen‐science projects can be challenging, requiring the building and maintenance of many relationships and a multidisciplinary approach that goes well beyond the usual activities of an academic researcher. Well‐designed, question‐first citizen science has the capacity to achieve both scientific rigor and meaningful engagement with volunteer participants. [ABSTRACT FROM AUTHOR]

Wildfires are increasing in both frequency and intensity in many ecosystems, with climate change models predicting further escalations in fire-prone environments. Set against this background is the global decline of amphibians, with up to 40% of species facing extinction from multiple additive threats. Despite these disturbing figures, it is currently unclear how increasing fire frequency may impact the long-term persistence of frog populations., Following a severe wildfire in south-eastern Australia in 2009, field surveys indicated healthy tree frog populations. However, the 2009 fire had significant impacts on genetic diversity, including increased levels of inbreeding and declines in effective population size., Using stochastic population modelling under a range of fire-frequency scenarios, we demonstrate that amphibian populations in fire-prone environments may be increasingly vulnerable to extinction, particularly where rates of immigration are low., Synthesis and applications. This study of amphibian population genetics before and after a major wildfire emphasizes the importance of integrating both ecological and genetic data into population models. This will help managers make more appropriate conservation decisions regarding fire management of natural environments, especially those containing threatened populations. Priorities for agencies involved in planning controlled burns should consider carefully the timing of controlled burns, along with maintaining habitat connectivity. [ABSTRACT FROM AUTHOR]

1. Ecologists and conservation biologists consider many issues when designing a field study, such as the expected value of the data, the interests of the study species, the welfare of individual organisms and the cost of the project. These different issues or values often conflict; however, neither animal ethics nor environmental ethics provides practical guidance on how to assess trade-offs between them. 2. We developed a decision framework for considering trade-offs between values in ecological research, drawing on the field of ecological ethics. We used a case study of the population genetics of three frog species, in which a researcher must choose between four methods of sampling DNA from the study animals. We measured species welfare as the reduction in population growth rate following sampling, and assessed individual welfare using two different definitions: (i) the level of suffering experienced by an animal, and (ii) the level of suffering combined with loss of future life. 3. Tipping the tails of tadpoles ranked as the best sampling method for species welfare, while collecting whole tadpoles and buccal swabbing of adult frogs ranked best for the first and second definitions of individual welfare, respectively. Toe clipping of adult frogs ranked as the worst sampling method for species welfare and the first definition of individual welfare, and equal worst for the second definition of individual welfare. 4. When considering species and individual welfare simultaneously, toe clipping was clearly inferior to the other sampling methods, but no single sampling method was clearly superior to the other three. Buccal swabbing, collecting tadpoles and tail tipping were all preferred options, depending on the definition of individual welfare and the level of precision with which we assessed species welfare. 5. Synthesis and applications. The decision framework we present can be used by ecologists to assess ethical and other trade-offs when planning field studies. A formal decision analysis makes transparent how a researcher might negotiate competing ethical, financial and practical objectives. Defining the components of the decision in this way can help avoid errors associated with human judgement and linguistic uncertainty. [ABSTRACT FROM AUTHOR]

Male frogs call to attract females for mating and to defend territories from rival males. Female frogs of some species prefer lower-pitched calls, which indicate larger, more experienced males. Acoustic interference occurs when background noise reduces the active distance or the distance over which an acoustic signal can be detected. Birds are known to call at a higher pitch or frequency in urban noise, decreasing acoustic interference from low-frequency noise. Using Bayesian linear regression, we investigated the effect of traffic noise on the pitch of advertisement calls in two species of frogs, the southern brown tree frog (Litoria ewingii) and the common eastern froglet (Crinia signifera). We found evidence that L. ewingii calls at a higher pitch in traffic noise, with an average increase in dominant frequency of 4.1 Hz/dB of traffic noise, and a total effect size of 123 Hz. This frequency shift is smaller than that observed in birds, but is still large enough to be detected by conspecific frogs and confer a significant benefit to the caller. Mathematical modelling predicted a 24% increase in the active distance of a L. ewingii call in traffic noise with a frequency shift of this size. Crinia signifera may also call at a higher pitch in traffic noise, but more data are required to be confident of this effect. Because frog calls are innate rather than learned, the frequency shift demonstrated by L. ewingii may represent an evolutionary adaptation to noisy conditions. The phenomenon of frogs calling at a higher pitch in traffic noise could therefore constitute an intriguing trade-off between audibility and attractiveness to potential mates. [ABSTRACT FROM AUTHOR]

1. Toe clipping is commonly used in population ecology to identify individual amphibians, particularly frogs and toads. Toe clipping may influence the return rate of the marked animals, although results of previous studies have appeared to be contradictory. 2. We re-analysed available data using Bayesian statistics to examine how the return rate of frogs may change with the number of toes removed. 3. Our re-analysis indicated that toe clipping reduces the return rate by 4–11% for each toe removed after the first, assuming the effect is the same for all toes. 4. A second analysis allowed the effect of removing each toe to change linearly with the number removed. This indicated that when one toe had already been removed, the return rate was reduced by 3·5% (95% credibility interval of 0–7%) upon removal of a second. The reduction in return rate on removal of an additional toe was 30% (95% credibility interval of 20–39%) when seven toes had already been removed. 5. When considering the cumulative effect of toe clipping, the return rate of frogs with two toes removed was estimated to be 96% of those with one toe removed. This ratio decreased to 28% for frogs with eight toes removed. 6. Synthesis and applications. We found that the effect of toe clipping on the return rate of amphibians increases with the number of toes removed. Because this effect is reasonably consistent among studies, the estimated impact should be recognized in future work that uses toe clipping to estimate population sizes and survival rates. In addition, our study has important implications for the ethical treatment of animals, the continued use of toe clipping to mark species of conservation concern, and the removal of multiple toes from an individual frog or toad. Journal of Applied Ecology (2004) 41, 780 –786 [ABSTRACT FROM AUTHOR]

Loss and fragmentation of habitat resulting from the clearing of forests for agriculture and urban development threaten the persistence of thousands of species worldwide. The clearing of native forest to plant a monoculture of exotic trees may also reduce and fragment the habitat available for indigenous plants and animals. Metacommunity theory suggests that the species richness of a community in a patch of habitat will increase with patch size but decrease with patch isolation. We investigated whether replacement of native Eucalyptus forest with a plantation of Pinus radiata has reduced and fragmented habitat for frogs, leading to a lower species richness of frog communities in the pine plantation and in small and/or isolated remnant patches of native forest. We surveyed frogs at 60 sites at streams and wetlands in the pine plantation, remnant patches of native forest surrounded by pines, and adjacent areas of contiguous native forest near Tumut in New South Wales, Australia. Only two of eight species of frogs were recorded in the pine plantation, and regression modelling indicated that streams and wetlands in the pines supported fewer frog species than those in remnant patches or the intact native forest. In addition, species richness tended to be higher at wide, shallow swamps and marshes near the headwaters of streams, with herbs, grasses, shrubs, reeds, sedges and rushes in the emergent and fringing vegetation. There was little evidence to suggest that larger eucalypt remnants supported more species of frogs, or that remnants isolated by greater expanses of pines supported fewer species, but we had low power to detect these effects with our data set. Our results support the preservation of all remnants of native forest along drainage lines and around swamps, soaks and bogs, regardless of size. Where new pine plantations are established, for example, on cleared agricultural land, care should be taken to maintain the structural and vegetative characteristics of water bodies to ensure that they continue to provide suitable breeding habitat for frogs. [Copyright &y& Elsevier]

Environmental contamination contributes to the threatened status of many amphibian populations. Many contaminants alter behaviour at concentrations commonly experienced in the environment, with negative consequences for individual fitness, populations and communities. A comprehensive, quantitative evaluation of the behavioural sensitivity of amphibians is warranted to better understand the population-level and resultant ecological impacts of contaminants. We conducted a systematic review and meta-analysis evaluating behavioural changes following exposure to contaminants. Most studies were conducted in North America and Europe on larval stages, and 64% of the 116 studies focussed on the effects of insecticides. We found that a suite of contaminants influence a wide range of behaviours in amphibians, with insecticides typically invoking the strongest responses. In particular, insecticides increased rates of abnormal swimming, and reduced escape responses to simulated predator attacks. Our analysis identified five key needs for future research, in particular the need: (1) for researchers to provide more details of experimental protocols and results (2) to develop a strong research base for future quantitative reviews, (3) to broaden the suite of contaminants tested, (4) to better study and thus understand the effects of multiple stressors, and (5) to establish the ecological importance of behavioural alterations. Behavioural endpoints provide useful sub-lethal indicators of how contaminants influence amphibians, and coupled with standard ecotoxicological endpoints, can provide valuable information for population models assessing the broader ecological consequences of environmental contamination. Unlabelled Image • Chemical contamination is driving amphibian declines, often at sub-lethal concentrations. • We used meta-analysis to quantify responses to a suite of contaminants. • Contaminants caused abnormal swimming and affected escape responses. • Behaviours were typically altered in meaningful ways. • Understanding behavioural alterations help predict ecological implications. [ABSTRACT FROM AUTHOR]