Wildlife Forensic Investigations Research Articles

Whole genome survey of big cats (Genus: Panthera) identifies novel microsatellites of utility in conservation genetic study

Big cats (Genus: Panthera) are among the most threatened mammal groups of the world, owing to hunting, habitat loss, and illegal transnational trade. Conservation genetic studies and effective curbs on poaching are important for the conservation of these charismatic apex predators. A limited number of microsatellite markers exists for Panthera species and researchers often cross-amplify domestic cat microsatellites to study these species. We conducted data mining of seven Panthera genome sequences to discover microsatellites for conservation genetic studies of four threatened big cat species. A total of 32 polymorphic microsatellite loci were identified in silico and tested with 152 big cats, and were found polymorphic in most of the tested species. We propose a set of 12 novel microsatellite markers for use in conservation genetics and wildlife forensic investigations of big cat species. Cumulatively, these markers have a high discriminatory power of one in a million for unrelated individuals and one in a thousand for siblings. Similar PCR conditions of these markers increase the prospects of achieving efficient multiplex PCR assays. This study is a pioneering attempt to synthesise genome wide microsatellite markers for big cats.

Development of a multiplex, PCR-based genotyping assay for African and Asian elephants for forensic purposes.

Wildlife crimes and the threats they present to elephant populations raise the need to develop and implement DNA-based methodology as an aid for wildlife forensic investigations and conservation efforts. This study describes the development of a tetra-nucleotide repeat STR multiplex, genotyping assay that will identify Asian elephant (Elephas maximus) and African elephant (Loxodonta africana) DNA. The assay targets six tetra-nucleotide STRs and two sex-typing markers simultaneously in both genera of elephants, a first for elephant genotyping assays. The developed assay has potential application in wildlife investigations to associate a biological sample to a particular individual elephant and additionally in conservation science for population management.

Defining end user requirements for a field-based molecular detection system for wildlife forensic investigations

The increasing use of non-laboratory-based DNA and protein detection methods promise to provide rapid investigative intelligence and support sample prioritisation. Primarily developed for human forensic or medical applications, current systems may also show utility in the field of wildlife forensic science. However, it is currently unknown whether the requirements of the wildlife forensic community can be met by current non-laboratory based tools. Given the diverse array of stakeholders and sample types commonly encountered, it is necessary to first identify the needs of the community and then try and map their needs to current instrumentation. By using a market research style questionnaire, this study identified key requirements for a non-laboratory-based system following feedback from the wildlife forensic community. Data showed that there is strong support for field-based detection methods while highlighting concerns including contamination risks and reduced quality assurance associated with non-laboratory testing. Key species and applications were identified alongside hurdles to implementation and adoption. Broadly, the requirements align with many of the developmental drivers that have led to the rise of in-field portable detection instrumentation, specifically rapid detection within one hour, ease-of-use, and ≥95% accuracy. Several existing platforms exist that met some of the identified requirements but not all. With further collaboration between industry partners and the wildlife forensic community it is possible that new field-based systems can be developed and applied routinely.

A Novel Application of a Cryosectioning Technique to Aid Scat Hair Microanalysis.

Scat hair presents a diverse profile of hairs for morphological assessment that may find versatile applications in wildlife forensic investigations. Successful morphological assessment of scat hair microstructure, however, depends on a robust sectioning methodology. We assessed the feasibility and efficacy of a cryosectioning technique compared to that of a gold standard hand-sectioning technique. Scat hairs were embedded in paraffin wax and hand-sectioned, while cryopreserved scat hairs were sectioned with a cryostat. The results showed that cryosectioning preserved the pristine morphology of the scat hair and provided cross sections more amenable to high-resolution imaging of hair internal microstructure than hand-sectioning. The cryosectioning technique may find novel applications as a more reliable and robust technique to aid (i) scat hair internal microstructure analysis for cross-referencing with species identification keys in wildlife forensic studies and (ii) downstream toxicological analysis in wildlife forensic studies as hair biochemistry is not altered during cryopreservation.

Review of: Wildlife Forensic Investigation: Principles and Practice

Review of: <i>Wildlife Forensic Investigation: Principles and Practice</i>

Merging Wildlife and Environmental Monitoring Approaches with Forensic Principles: Application of Unconventional and Non-Invasive Sampling in Eco- Pharmacovigilance

Pharmaceutical residues in the environment have the potential to harm wildlife. A population’s fragility or an animal’s secretive nature may preclude capture and the use of invasive/destructive sampling techniques that are typically used in a risk assessment. Conventionally favoured matrices gathered opportunistically from carcasses have a finite lifespan, thereby limiting the detection window. This multidisciplinary paper aims to promote the use of non-invasive approaches and optimize use of even the most degraded carcasses. We highlight a selection of promising alternative, unconventional and underutilized sample types that could be applied in environmental monitoring efforts and wildlife forensic investigations. With a focus on non-steroidal anti-inflammatory drugs (NSAIDs), now under increasing scrutiny in the freshwater and terrestrial environment, we first illustrate current sampling practices and gaps in knowledge by summarizing exposure of: 1) aquatic organisms to urban effluent discharged into waterways, and, 2) scavenging species to veterinary residues in livestock and other carrion. We then consider the merits and limitations of a range of alternative environmentally robust sample options that offer a broader detection interval for NSAIDs, with emphasis on hair, wool and feathers. The viability of eyes/ocular material, bone matter, fecal matter, injection sites, ingesta/pellets and scavenging/coprophagous insects are also discussed.

John E. Cooper and Margaret E. Cooper (eds.): Wildlife forensic investigation—principles and practice

John E. Cooper and Margaret E. Cooper (eds.): Wildlife forensic investigation—principles and practice

Book Review: Wildlife Forensic Investigation: Principles and Practice

Book Review: Wildlife Forensic Investigation: Principles and Practice

Tiger hair morphology and its variations for wildlife forensic investigation

Tiger population has dramatically decreased due to illegal consumption and commercialisation of their body parts. Frequently, hair samples are the only evidence found in the crime scene. Thus, they play an important role in species identification for wildlife forensic investigation. In this study, we provide the first in-depth report on a variety of qualitative and quantitative characteristics of tiger guard hairs (24 hairs per individual from four individuals). The proposed method could reduce subjectivity of expert opinions on species identification based on hair morphology. Variations in 23 hair morphological characteristics were quantified at three levels: hair section, body region, and intra-species. The results indicate statistically significant variations in most morphological characteristics in all levels. Intra-species variations of four variables, namely hair length, hair index, scale separation and scale pattern, were low. Therefore, identification of tiger hairs using these multiple features in combination with other characteristics with high inter-species variations (e.g. medulla type) should bring about objective and accurate tiger hair identification. The method used should serve as a guideline and be further applied to other species to establish a wildlife hair morphology database. Statistical models could then be constructed to distinguish species and provide evidential values in terms of likelihood ratios.

Who is who? Identification of livestock predators using forensic genetic approaches

Molecular identifications of salivary DNA are increasingly applied in wildlife forensic investigations, and are successfully used to identify unknown livestock predators, or elucidate cases of large carnivore attacks to humans. In Europe most of livestock predations are attributed to wolves (Canis lupus), thought free-ranging dogs are sometime the responsible, and false predations are declared by breeders to obtain compensations. In this study we analyzed 33 salivary DNA samples collected from the carcasses of 13 sheep and a horse presumably predated by wolves in seven farms in central Italy. Reliable individual genotypes were determined in 18 samples (corresponding to samples from nine sheep and the horse) using 12 unlinked autosomal microsatellites, mtDNA control-region sequences, a male-specific ZFX/ZFY restriction-site and four Y-linked microsatellites. Results indicate that eight animals were killed by five wolves (a male and four different females), the ninth by a female dog while the horse was post-mortem consumed by a male dog. The genotype of one female wolf matched with the genetic profile of a female wolf that was non-invasively sampled 4 years before in the same area near livestock predation remains. Genetic identifications always supported the results of veterinary reports. These findings show that salivary DNA genotyping, together with detailed veterinary field and necropsy reports, provides evidence which helps to correctly identify species, gender and individual genetic profiles of livestock predators, thus contributing to clarify attack dynamics and to evaluate the impact of wolf predations on husbandry.

The use of DNA identification in prosecuting wildlife-traffickers in Australia: do the penalties fit the crimes?

The use of genetic identification techniques in wildlife forensic investigations has increased significantly in recent years. The utilization of DNA is especially important when species identification using other methods are inconclusive. Australia has strict laws against illegal importation of wildlife as well as laws to protect its unique biodiversity from pests and diseases of quarantine concern. Two separate case studies in which genetic identification was essential for species identification are presented-the first involved illegally held shark fins, the second illegally imported live bird eggs. In the latter case genetic identification enabled charges to be laid for illegal importation of CITES Appendix I species. Australian laws allow for some of the highest penalties for illegal trade of wildlife compared to other countries, however only a fraction of cases are prosecuted and penalties applied to date have been lower than the maximum permitted. Both of the reported cases resulted in fines, and one in imprisonment of the offender, which provides a persuasive precedent for future prosecutions.