Evaluation of camera traps for monitoring European rabbits before and after control operations in Otago, New Zealand

2012 ◽  
Vol 39 (7) ◽  
pp. 621 ◽  
Author(s):  
A. David M. Latham ◽  
Graham Nugent ◽  
Bruce Warburton
Keyword(s):  
New Zealand ◽  
Statistical Power ◽  
Vantage Point ◽  
Camera Traps ◽  
Alternative Methods ◽  
Monitoring Methods ◽  
Control Operation ◽  
Point Counts ◽  
Rabbit Haemorrhagic Disease ◽  
European Rabbits

Context European rabbits (Oryctolagus cuniculus) are reaching plague proportions again in some parts of New Zealand as the effect of rabbit haemorrhagic disease begins to wane. Effective monitoring techniques are required to quantify the success of alternative methods of controlling rabbits, such as poisoning. Aim To evaluate camera traps as a method of estimating the percentage of rabbits killed in a poison control operation, and to compare results obtained from cameras with those from traditional monitoring methods (spotlight transects and vantage-point counts). Methods We deployed cameras and conducted vantage-point counts and spotlight transects to compare a priori statistical power. We then used these monitoring methods to estimate percentage kill from a case study rabbit-control operation using sodium fluoroacetate (compound 1080). Key results Cameras had good statistical power to detect large reductions in rabbit numbers (>90%) and the percentage kill estimated using cameras was comparable with spotlight transects and vantage-point counts. Conclusions Cameras set up at fixed sampling locations can be an effective method of quantitatively assessing rabbit population control outcomes. We recommend that ≥6 cameras per 100 ha should remain active for at least 5 days before and 5 days following control, so as to obtain reliable estimates of percentage kill. Implications Cameras may be preferable to conventional monitoring methods where there is insufficient area to walk or drive transects, terrain is too rugged or scrubby for transects, and there are no or few vantage points from which to count rabbits.

Capturing the cryptic: a comparison of detection methods for stoats (Mustela erminea) in alpine habitats

2017 ◽  
Vol 44 (5) ◽  
pp. 418 ◽  
Author(s):  
Des H. V. Smith ◽  
Kerry A. Weston
Keyword(s):  
New Zealand ◽  
Early Summer ◽  
Camera Traps ◽  
Detection Methods ◽  
Monitoring Methods ◽  
Mustela Erminea ◽  
Detection Rates ◽  
Artificial Nests ◽  
Alternative Detection ◽  
Tracking Tunnels

Context The ability to monitor the spatial distribution and abundance of species is essential for detecting population changes, and assessing the progress of conservation management programs. Stoats (Mustela erminea) are a serious conservation pest in New Zealand, but current monitoring methods are not sensitive enough to detect stoats in all situations. Aims We compare the effectiveness of the most commonly employed method for monitoring mustelids in New Zealand, footprint-tracking tunnels, with two alternative detection methods, camera traps and artificial nests. We were interested in determining whether alternative detection methods were more sensitive in detecting stoats than tracking tunnels. Methods We established a network of tracking tunnels, artificial nests and camera traps within alpine habitat. Devices were checked for stoat detections weekly across two seasons, in spring–early summer and autumn. Differences in detection rates and cost effectiveness among methods were analysed among seasons. Key results In spring–early summer, the time to first stoat detection using footprint-tracking tunnels was 61 days, compared with 7 days for camera traps and 8 days for artificial nests. The rate of stoat detection using artificial nests was significantly higher than it was using tracking tunnels (coef = 3.05 ± 1.29, P = 0.02), and moderately higher using camera traps (coef = 1.34 ± 1.09, P = 0.22). In autumn, when overall detectability of stoats was higher, there was no significant difference in detection rates among the three methods, although camera traps again recorded the earliest detection. Artificial nests were the most cost effective detection method in both seasons. Conclusions Artificial nests and camera traps were more efficient at detecting stoats during their spring breeding season (when they are known to be difficult to detect), compared with the more established footprint-tracking tunnel method. Artificial nests have potential to be developed into a monitoring index for small mammals, although further research is required. Both methods provide an important alternative to footprint tracking indices for monitoring stoats. Implications Our study demonstrated the importance of calibration among different monitoring methods, particularly when the target species is difficult to detect. We hypothesise that detection methods that do not rely on conspicuous, artificially constructed devices, may be more effective for monitoring small, cryptic mammals.

scholarly journals Age and Infectious Dose Significantly Affect Disease Progression after RHDV2 Infection in Naïve Domestic Rabbits

Viruses ◽  
2021 ◽  
Vol 13 (6) ◽  
pp. 1184
Author(s):  
Robyn N. Hall ◽  
Tegan King ◽  
Tiffany O’Connor ◽  
Andrew J. Read ◽  
Jane Arrow ◽  
...  
Keyword(s):  
New Zealand ◽  
Disease Progression ◽  
Case Fatality Rate ◽  
Low Dose ◽  
Case Fatality ◽  
Wild Rabbit ◽  
Fatality Rate ◽  
Infectious Dose ◽  
Welfare Impacts ◽  
Rabbit Haemorrhagic Disease

Rabbit haemorrhagic disease virus 2 (RHDV2 or GI.2, referring to any virus with lagovirus GI.2 structural genes) is a recently emerged calicivirus that causes generalised hepatic necrosis and disseminated intravascular coagulation leading to death in susceptible lagomorphs (rabbits and hares). Previous studies investigating the virulence of RHDV2 have reported conflicting results, with case fatality rates ranging from 0% to 100% even within a single study. Lagoviruses are of particular importance in Australia and New Zealand where they are used as biocontrol agents to manage wild rabbit populations, which threaten over 300 native species and result in economic impacts in excess of $200 million AUD annually to Australian agricultural industries. It is critically important that any pest control method is both highly effective (i.e., virulent, in the context of viral biocontrols) and has minimal animal welfare impacts. To determine whether RHDV2 might be a suitable candidate biocontrol agent, we investigated the virulence and disease progression of a naturally occurring Australian recombinant RHDV2 in both 5-week-old and 11-week-old New Zealand White laboratory rabbits after either high or low dose oral infection. Objective measures of disease progression were recorded through continuous body temperature monitoring collars, continuous activity monitors, and twice daily observations. We observed a 100% case fatality rate in both infected kittens and adult rabbits after either high dose or low dose infection. Clinical signs of disease, such as pyrexia, weight loss, and reduced activity, were evident in the late stages of infection. Clinical disease, i.e., welfare impacts, were limited to the period after the onset of pyrexia, lasting on average 12 h and increasing in severity as disease progressed. These findings confirm the high virulence of this RHDV2 variant in naïve rabbits. While age and infectious dose significantly affected disease progression, the case fatality rate was consistently 100% under all conditions tested.

Using complementary remote detection methods for retrofitted eco-passages: a case study for monitoring individual koalas in south-east Queensland

2016 ◽  
Vol 43 (5) ◽  
pp. 369 ◽  
Author(s):  
C. E. Dexter ◽  
R. G. Appleby ◽  
J. P. Edgar ◽  
J. Scott ◽  
D. N. Jones
Keyword(s):  
Road Construction ◽  
Primary Objective ◽  
Correlated Data ◽  
Camera Traps ◽  
Detection Methods ◽  
Urban Landscapes ◽  
Monitoring Methods ◽  
Monitoring Method ◽  
Phascolarctos Cinereus ◽  
The Individual

Context Vehicle-strike has been identified as a key threatening process for koala (Phascolarctos cinereus) survival and persistence in Australia. Roads and traffic act as barriers to koala movement and can impact dispersal and metapopulation dynamics. Given the high cost of wildlife mitigation structures such as purpose-built fauna-specific underpasses or overpasses (eco-passages), road construction and management agencies are constantly seeking cost-effective strategies that facilitate safe passage for fauna across roads. Here we report on an array of detection methods trialled to verify use of retrofitted road infrastructure (existing water culverts or bridge underpasses) by individual koalas in fragmented urban landscapes in south-east Queensland. Aims The study examined whether the retrofitting of existing road structures at six sites facilitated safe passage for koalas across roads. Our primary objective was to record utilisation of retrofitted infrastructure at the level of the individual. Methods We used a combination of existing monitoring methods such as GPS/VHF collars, camera traps, sand plots, and RFID tags, along with a newly developed animal-borne wireless identification (WID) tag and datalogging system, specifically designed for this project, to realise the study aims. Key results We were able to verify 130 crossings by koalas involving a retrofitted structure or a road surface over a 30-month period by using correlated data from complementary methods. We noted that crossings were generally uncommon and mostly undertaken by only a subset of our tagged individuals at each site (21% overall). Conclusions An important element of this study was that crossing events could be accurately determined at the level of the individual. This allowed for detailed assessment of eco-passage usage, rather than the more usual approach of simply recording species’ presence. Implications This study underscores the value of identifying the constraints of each individual monitoring method in relation to site conditions. It also highlights the benefits of contingency planning to limit data loss (i.e. using more than one method to collect data). We suggest an approach that uses complementary monitoring methods has significant advantages for researchers, particularly with reference to improving understanding of whether eco-passages are meeting their prescribed conservation goals.

scholarly journals Molecular epidemiology of Rabbit haemorrhagic disease virus

2002 ◽  
Vol 83 (10) ◽  
pp. 2461-2467 ◽  
Author(s):  
S. R. Moss ◽  
S. L. Turner ◽  
R. C. Trout ◽  
P. J. White ◽  
P. J. Hudson ◽  
...  
Keyword(s):  
Disease Virus ◽  
Nucleotide Sequencing ◽  
Molecular Evidence ◽  
Rabbit Haemorrhagic Disease Virus ◽  
Rabbit Haemorrhagic Disease ◽  
Molecular Phylogenetic ◽  
Virulent Virus ◽  
Rabbit Bone ◽  
European Rabbits ◽  
Haemorrhagic Disease

Millions of domestic and wild European rabbits (Oryctolagus cuniculus) have died in Europe, Asia, Australia and New Zealand during the past 17 years following infection by Rabbit haemorrhagic disease virus (RHDV). This highly contagious and deadly disease was first identified in China in 1984. Epidemics of RHDV then radiated across Europe until the virus apparently appeared in Britain in 1992. However, this concept of radiation of a new and virulent virus from China is not entirely consistent with serological and molecular evidence. This study shows, using RT–PCR and nucleotide sequencing of RNA obtained from the serum of healthy rabbits stored at 4 °C for nearly 50 years, that, contrary to previous opinions, RHDV circulated as an apparently avirulent virus throughout Britain more than 50 years ago and more than 30 years before the disease itself was identified. Based on molecular phylogenetic analysis of British and European RHDV sequences, it is concluded that RHDV has almost certainly circulated harmlessly in Britain and Europe for centuries rather than decades. Moreover, analysis of partial capsid sequences did not reveal significant differences between RHDV isolates that came from either healthy rabbits or animals that had died with typical haemorrhagic disease. The high stability of RHDV RNA is also demonstrated by showing that it can be amplified and sequenced from rabbit bone marrow samples collected at least 7 weeks after the animal has died.

Should immunocontraception be used for wildlife population management?

2004 ◽  
Vol 26 (1) ◽  
pp. 61 ◽  
Author(s):  
DW Cooper
Keyword(s):  
Immune Response ◽  
New Zealand ◽  
Immune Responses ◽  
Fundamental Problem ◽  
Public Perceptions ◽  
Published Data ◽  
Red Foxes ◽  
European Rabbits ◽  
Selection For ◽  
Self Antigens

Immunocontraception involves eliciting an immune response against eggs, sperm or hormones so that successful reproduction is prevented. Work in Australasia is aimed at European rabbits (Oryctolagus cuniculus), red foxes (Vulpes vulpes), house mice (Mus musculus), common brushtail possums (Trichosurus vulpecula), koalas (Phascolartcos cinereus) and kangaroos (Macropus spp.), with the vaccines involved all containing self antigens or their relatives. Two fundamental problems have been inadequately addressed in this research. The first problem is that it is difficult to obtain strong immune responses against self antigens and so the vaccines may be ineffective. Most published data on the effect of immunocontraceptives on reproduction involve the use of an adjuvant of which there are many kinds. The materials enhance the immune response greatly. The most frequently used is Freund?s adjuvant which can cause chronic suffering. Its use on wildlife will lead to very negative public perceptions. There has been no convincing demonstration that successful immunocontraception is possible with any method of vaccination likely to be used in the field, if success is defined as contraception of a proportion of the population high enough for management requirements. If it is assumed that success can be achieved, the second fundamental problem arises with two potential consequences. Even with adjuvant, a substantial minority of the vaccinated animals remains fertile. The first consequence is that since failure to be contracepted is likely to be in part genetic, there is likely to be rapid selection for these non-responders. The method will become ineffective in a few generations. The second problem is that the offspring of the animals which breed will have altered immune responses. Their capacities to respond to their own pathogens or to harbor pathogens of other species in the same ecosystem are likely to be changed. The presence of chlamydia in P. cinereus and bovine tuberculosis in New Zealand T. vulpecula means that responses to these pathogens would have to be studied in offspring of immunocontracepted parents to ensure that the offspring were not more susceptible to them. New Zealand intentions to put an immunocontraceptive into a T. vulpecula gut worm must be viewed with caution by Australia. The eggs of transgenic worms will be easily transplanted either accidentally or deliberately back into Australia, and so infect T. vulpecula in Australia.

scholarly journals Comparison of predation by two suburban cats in New Zealand

2017 ◽  
Vol 3 (1) ◽  
pp. 85-90 ◽  
Author(s):  
John E. C. Flux
Keyword(s):  
New Zealand ◽  
House Sparrow ◽  
Bird Species ◽  
House Mice ◽  
Domestic Cats ◽  
Mesopredator Release ◽  
Song Thrush ◽  
Top Predators ◽  
European Rabbits ◽  
Native Birds

AbstractTo study the effects domestic cats may have on surrounding wildlife, a complete list was made of 558 items caught in the garden or brought into the house by one cat over 17 years, from 1988 to 2005. The effect on prey populations was assessed by comparing their abundance with the previous 15 years’ population without a cat. On balance, this cat (Cat 1) was clearly beneficial to the native bird species by killing rodents and deterring mustelids. The diet of a second cat (Cat 2) was recorded in the same way from 2006 to 2016. This cat caught half the number of items 148:287, but in the same proportions: house mice (37.8:42.6); ship rats (12.8:12.1); European rabbits (all young) (8.1:6.7); weasels (0.7:0.4); dunnock (12.8:9.2); house sparrow (2.0:3.1); blackbird (2.7:2.5); song thrush (1.4:1.3); European greenfinch (0.7:5.8); chaffinch (0.7:3.3); silvereye (10.1:8.3); New Zealand fantail (2.0:1.0); lizards (8.1:1.7). Despite this, there were significant differences: Cat 2 avoided finches (2:28, P = 0.004), and took a few more lizards (12:5). For both cats, birds apparently formed about a third of their diet: 33.4% and 34.5%, but comparison of the proportion of birds and rodents brought into the house (12:92) and found dead away from the house (49:45) implies that 320 rodent kills may have been missed, being far more difficult to find. As top predators, these cats were clearly beneficial to native birds, and proposed control or elimination may precipitate mesopredator release and a rabbit problem.

scholarly journals Effects of supplementary feed for game birds on activity of brown rats Rattus norvegicus on arable farms

2020 ◽  
Author(s):  
Siti Md Saad ◽  
Roy Sanderson ◽  
Peter Robertson ◽  
Mark Lambert
Keyword(s):  
Linear Models ◽  
Camera Traps ◽  
Monitoring Methods ◽  
Mixed Effect ◽  
Factors Affecting ◽  
Game Bird ◽  
Game Birds ◽  
Bird Feeders ◽  
Brown Rat ◽  
Supplementary Feed

Abstract Brown rats are widespread in agroecosystems, but our understanding of factors affecting their activity is incomplete due to cryptic, nocturnal behaviours. Indirect monitoring methods include tracking plates and camera traps. Supplementary feeding of game birds may provide resources for rats away from farm buildings, allowing them to persist in winter when there is little other food available. Developing reliable methods to monitor such populations will facilitate landscape-scale studies of rat populations in farm environments and aid ecologically based approaches for controlling rats on farms. We compared camera traps and tracking plates to monitor brown rat activity near game bird feeders at a mixed farm in Northumberland, UK. Generalized linear models (GLM) were used to compare rat incidence estimated from camera traps and tracking plates. A strong positive relationship was found between the two methods, although tracking plate estimates were less reliable when rat activity was very low. Factors that affected populations of brown rats near game bird feeders were assessed via linear mixed-effect models (LMM) of monthly tracking plate data (October 2017 to September 2018). Populations were highest at the feeders (0 m) compared with further away (10 m, 20 m) and were also higher in periods of cold, wet weather and when more food was available from the feeders. Rodenticide application near feeders did not significantly affect activity, nor did land cover 100 m around each feeder. A highly significant relationship was detected with food supply, suggesting that the use of game bird feeders could potentially have major impacts on rat population dynamics.

scholarly journals Snap happy: camera traps are an effective sampling tool when compared with alternative methods

2019 ◽  
Vol 6 (3) ◽  
pp. 181748 ◽  
Author(s):  
Oliver R. Wearn ◽  
Paul Glover-Kapfer
Keyword(s):  
Quantitative Data ◽  
Evidence Base ◽  
Global Scale ◽  
Camera Traps ◽  
Alternative Methods ◽  
Biodiversity Monitoring ◽  
Visual Aids ◽  
Survey Tool ◽  
Number Of Species ◽  
Technological Advances

Camera traps have become a ubiquitous tool in ecology and conservation. They are routinely deployed in wildlife survey and monitoring work, and are being advocated as a tool for planetary-scale biodiversity monitoring. The camera trap's widespread adoption is predicated on the assumption of its effectiveness, but the evidence base for this is lacking. Using 104 past studies, we recorded the qualitative overall recommendations made by study authors (for or against camera traps, or ambiguous), together with quantitative data on the effectiveness of camera traps (e.g. number of species detected or detection probabilities) relative to 22 other methods. Most studies recommended the use of camera traps overall and they were 39% more effective based on the quantitative data. They were significantly more effective compared with live traps (88%) and were otherwise comparable in effectiveness to other methods. Camera traps were significantly more effective than other methods at detecting a large number of species (31% more) and for generating detections of species (91% more). This makes camera traps particularly suitable for broad-spectrum biodiversity surveys. Film camera traps were found to be far less effective than digital models, which has led to an increase in camera trap effectiveness over time. There was also evidence from the authors that the use of attractants with camera traps reduced their effectiveness (counter to their intended effect), while the quantitative data indicated that camera traps were more effective in closed than open habitats. Camera traps are a highly effective wildlife survey tool and their performance will only improve with future technological advances. The images they produce also have a range of other benefits, for example as digital voucher specimens and as visual aids for outreach. The evidence-base supports the increasing use of camera traps and underlines their suitability for meeting the challenges of global-scale biodiversity monitoring.

scholarly journals Wariness of coyotes to camera traps relative to social status and territory boundaries

2003 ◽  
Vol 81 (12) ◽  
pp. 2015-2025 ◽  
Author(s):  
Eveline S Séquin ◽  
Michael M Jaeger ◽  
Peter F Brussard ◽  
Reginald H Barrett
Keyword(s):  
Social Status ◽  
Human Activity ◽  
Canis Latrans ◽  
Primary Objective ◽  
Vantage Point ◽  
Camera Traps ◽  
Approach Response ◽  
Human Presence ◽  
Camera Systems ◽  
Set Up

The primary objective of this study was to develop a better understanding of coyote (Canis latrans) wariness particularly as it related to social status. We determined that territory status (controlling alpha, resident beta, or nonterritorial transient) affected vulnerability to photo-capture by infrared-triggered camera systems. All coyotes were wary of cameras, leading to relatively low numbers of photo-captures, most of which occurred at night. Alphas were significantly underrepresented in photographs and were never photo-captured inside their own territories. Betas were photographed inside and outside their territories, whereas transients were most often photographed on edges of territories. Both alphas and betas were photographed more often on territorial edges when outside their territories. We next addressed the question of how alphas were better able to avoid photo-capture. Alphas tracked human activity within their territories and presumably learned the locations of cameras as they were being set up. They did this either by approaching our location directly or by moving to a vantage point from where they could observe us. Betas and transients either withdrew or did not respond to human activity. Trials in which a dog was present were more likely to elicit an approach response from alphas. Avoidance of camera stations and the tracking of human activity implied wariness toward objects or locations resulting from their learned association with human presence rather than neophobia toward the objects themselves.

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