Hybridisation rates, population structure, and dispersal of sambar deer (Cervus unicolor) and rusa deer (Cervus timorensis) in south-eastern Australia
- Hill, Erin, Murphy, Nicholas, Li-Williams, Scarlett, Davies, Christopher, Forsyth, David, Comte, Sebastien, Rollins, Lee, Hogan, Fiona, Wedrowicz, Faye, Crittle, Troy, Thomas, Elaine, Woodford, Luke, Pacioni, Carlo
- Authors: Hill, Erin , Murphy, Nicholas , Li-Williams, Scarlett , Davies, Christopher , Forsyth, David , Comte, Sebastien , Rollins, Lee , Hogan, Fiona , Wedrowicz, Faye , Crittle, Troy , Thomas, Elaine , Woodford, Luke , Pacioni, Carlo
- Date: 2023
- Type: Text , Journal article
- Relation: Wildlife Research Vol. 50, no. 9 (2023), p. 669-687
- Full Text:
- Reviewed:
- Description: Context. Introduced populations of sambar deer (Cervus unicolor) and rusa deer (Cervus timorensis) are present across south-eastern Australia and are subject to local population control to alleviate their negative impacts. For management to be effective, identification of dispersal capability and management units is necessary. These species also readily hybridise, so additional investigation of hybridisation rates across their distributions is necessary to understand the interactions between the two species. Aims. Measure the hybridisation rate of sambar and rusa deer, assess broad-scale population structure present within both species and identify distinct management units for future population control, and measure the likely dispersal capability of both species. Methods. In total, 198 sambar deer, 189 rusa deer, and three suspected hybrid samples were collected across Victoria and New South Wales (NSW). After sequencing and filtering, 14 099 polymorphic single-nucleotide polymorphism (SNP) markers were retained for analysis. Hybridisation rates were assessed before the data were split by species to identify population structure, diversity indices, and dispersal distances. Key results. Across the entire dataset, 17 hybrids were detected. Broad-scale population structure was evident in sambar deer, but not among the sites where rusa deer were sampled. Analysis of dispersal ability showed that a majority of deer movement occurred within 20 km in both species, suggesting limited dispersal. Conclusions. Distinct management units of sambar deer can be identified from the dataset, allowing independent population control. Although broad-scale population structure was not evident in the rusa deer populations, dispersal limits identified suggest that rusa deer sites sampled in this study could be managed separately. Sambar × rusa deer hybrids are present in both Victoria and NSW and can be difficult to detect on the basis of morphology alone. Implications. Genetic analysis can identify broad-scale management units necessary for population control, and estimates of dispersal capability can assist in delineating management units where broad-scale population structure may not be apparent. The negative impacts associated with hybridisation require further investigation to determine whether removal of hybrids should be considered a priority management aim. © 2023 The Author(s) (or their employer(s)). Published by CSIRO Publishing.
- Authors: Hill, Erin , Murphy, Nicholas , Li-Williams, Scarlett , Davies, Christopher , Forsyth, David , Comte, Sebastien , Rollins, Lee , Hogan, Fiona , Wedrowicz, Faye , Crittle, Troy , Thomas, Elaine , Woodford, Luke , Pacioni, Carlo
- Date: 2023
- Type: Text , Journal article
- Relation: Wildlife Research Vol. 50, no. 9 (2023), p. 669-687
- Full Text:
- Reviewed:
- Description: Context. Introduced populations of sambar deer (Cervus unicolor) and rusa deer (Cervus timorensis) are present across south-eastern Australia and are subject to local population control to alleviate their negative impacts. For management to be effective, identification of dispersal capability and management units is necessary. These species also readily hybridise, so additional investigation of hybridisation rates across their distributions is necessary to understand the interactions between the two species. Aims. Measure the hybridisation rate of sambar and rusa deer, assess broad-scale population structure present within both species and identify distinct management units for future population control, and measure the likely dispersal capability of both species. Methods. In total, 198 sambar deer, 189 rusa deer, and three suspected hybrid samples were collected across Victoria and New South Wales (NSW). After sequencing and filtering, 14 099 polymorphic single-nucleotide polymorphism (SNP) markers were retained for analysis. Hybridisation rates were assessed before the data were split by species to identify population structure, diversity indices, and dispersal distances. Key results. Across the entire dataset, 17 hybrids were detected. Broad-scale population structure was evident in sambar deer, but not among the sites where rusa deer were sampled. Analysis of dispersal ability showed that a majority of deer movement occurred within 20 km in both species, suggesting limited dispersal. Conclusions. Distinct management units of sambar deer can be identified from the dataset, allowing independent population control. Although broad-scale population structure was not evident in the rusa deer populations, dispersal limits identified suggest that rusa deer sites sampled in this study could be managed separately. Sambar × rusa deer hybrids are present in both Victoria and NSW and can be difficult to detect on the basis of morphology alone. Implications. Genetic analysis can identify broad-scale management units necessary for population control, and estimates of dispersal capability can assist in delineating management units where broad-scale population structure may not be apparent. The negative impacts associated with hybridisation require further investigation to determine whether removal of hybrids should be considered a priority management aim. © 2023 The Author(s) (or their employer(s)). Published by CSIRO Publishing.
Predicting deer-vehicle collision risk across Victoria, Australia
- Davies, Christopher, Wright, Wendy, Hogan, Fiona, Visintin, Casey
- Authors: Davies, Christopher , Wright, Wendy , Hogan, Fiona , Visintin, Casey
- Date: 2020
- Type: Text , Journal article
- Relation: Australian Mammalogy Vol. 42, no. 3 (2020), p. 293-301
- Full Text: false
- Reviewed:
- Description: The risk of deer-vehicle collisions (DVCs) is increasing in south-east Australia as populations of introduced deer expand rapidly. There are no investigations of the spatial and temporal patterns of DVC or predictions of where such collisions are most likely to occur. Here, we use an analytical framework to model deer distribution and vehicle movements in order to predict DVC risk across the State of Victoria. We modelled the occurrence of deer using existing occurrence records and geographic climatic variables. We estimated patterns of vehicular movements from records of average annual daily traffic and speeds. Given the low number of DVCs reported in Victoria, we used a generalised linear regression model fitted to DVCs in California, USA. The fitted model coefficients suggested high collision risk on road segments with high predicted deer occurrence, moderate traffic volume and high traffic speed. We used the California deer model to predict collision risk on Victorian roads and validated the predictions with two independent datasets of DVC records from Victoria. The California deer model performed well when comparing predictions of collision risk to the independent DVC datasets and generated plausible DVC risk predictions across the State of Victoria. © 2020 Australian Mammal Society.
- Description: This research was supported by an Australian Government Research Training Program (RTP) scholarship and Federation University Australia’s School of Health and Life Science.
- «
- ‹
- 1
- ›
- »