Eating away at protected areas: Total grazing pressure is undermining public land conservation

Shifts in floristic composition and structure in Australian rangelands

Monitoring shifts in vegetation composition over time is essential for tracking biodiversity changes and for designing ecosystem management strategies. In Australia, the Terrestrial Ecosystem Research Network (TERN) provides a continent-wide network of monitoring sites (AusPlots) that can be used to assess the shifts in vegetation composition and structure of Australian Major Vegetation Groups (MVGs). Here we use time-series site data to quantify the extent and rate of MVG shifts between repeat visits and to recommend the most appropriate sampling frequency for specific MVGs. The research area spans a ~1,500 km latitudinal gradient within south/central Australia from arid rangelands in the north to Mediterranean vegetation in the south. The standardized AusPlots protocol was employed to repeatedly survey 103 one-hectare plots, assessed between 2011 and 2019. Floristic and growth form dissimilarities between visits were calculated with distance metrics and then regressed against survey interval. Multivariate ordination was used to explore temporal floristic shifts. Rank-dominance curves were used to display variations in species' importance. Between repeated visits, sites exhibited high variability for all vegetation parameters and trajectories. However, several trends emerged: (a) Species composition moved away from baseline linearly with intervals between surveys. (b) The rate of species turnover was approximately double in communities that are herbaceous versus woody-dominated. (c) Species abundances and growth forms shift at different speeds. All floristic and structural metrics shifted between re-visits, with varying magnitude and speed, but herbaceous-dominated plots showed higher floristic dynamism. Although the expanse, logistics, and the short time between visits constrained our analysis and interpretation, our results suggest that shorter revisit intervals may be appropriate for herbaceous compared to woody systems to track change most efficiently.

Accounting for spatial heterogeneity in the added conservation value of land protection when prioritizing protected areas

To combat biodiversity loss, there is increasing interest in safeguarding habitat by expanding protected areas. Given limited resources in conservation, organizations must invest in places that will add the greatest amount of value in species protection. To determine the added conservation value of protection, one needs to consider the level of human disturbance in areas that would result if they were left unprotected. In recent years, data resources have become available that reveal the spatial heterogeneity in human disturbance over large spatial extents worldwide. We investigated how accounting for heterogeneity in future disturbance in unprotected areas affects prioritization of protected areas by determining the added value offered by protection of different areas. We applied a complementarity-based framework for protected area prioritization to select protected areas in the coterminous United States under different assumptions about the heterogeneity of future disturbance in unprotected areas. Prioritizing protected areas while incorrectly assuming spatially homogeneous disturbance in unprotected areas, a common assumption, led to a loss of 76% of possible conservation gain for a given budget. The conservation return on investment from protecting candidate areas was positively correlated (0.44) to future human disturbance in that area if it was left unprotected. Our results show that the ability to identify cost-effective protected area networks depends on how one accounts for the ecological contribution of private lands that remain unprotected.

The Sanjiangyuan Nature Reserve Is Partially Effective in Mitigating Human Pressures

Protected areas play significant roles in protecting biodiversity by mitigating human activities. As an indicator for human activities, the human footprint (HF) can be used to assess the effectiveness of protected areas. We developed a HF dataset for the Sanjiangyuan region in China after localizing the global HF model. Then we used it to assess the effectiveness of Sanjiangyuan nature reserve (SNR) in mitigating human pressures. Our results suggest that the HF value for the Sanjiangyuan region was generally low from 1995 to 2015, with a fluctuating increasing trend. The SNR is partially effective in mitigating human pressures. For 2005–2010, the HF values decreased both within and outside the reserve with more decreases for the outside. For the three functional zones of the SNR, our results show that the HF values decreased during 2005–2010 for all of them, with the largest decrease in the experimental area, and increased during 2010–2015, with the lowest increase in the core areas. The results we obtained are consistent with ecological indicator-based assessments. It is a challenge for the government to balance conservation and development in establishing Sanjiangyuan National Park.

The Perils of Being Populous: Control and Conservation of Abundant Kangaroo Species

Australia's first people managed landscapes for kangaroo species as important elements of their diet, accoutrements and ceremony. This developed and persisted for about 65,000 years. The second wave of colonists from the United Kingdom, Ireland and many subsequent countries introduced familiar domesticated livestock and they have imposed their agricultural practices on the same landscapes since 1788. This heralded an ongoing era of management of kangaroos that are perceived as competitors to livestock and unwanted consumers of crops. Even so, a kangaroo image remains the iconic identifier of Australia. Kangaroo management is shrouded in dogma and propaganda and creates a tension along a loose rural-city divide. This divide is further dissected by the promotion of the consumption of kangaroo products as an ecological good marred by valid concerns about hygiene and animal welfare. In the last decade, the fervour to suppress and micro-manage populations of some kangaroo species has mounted. This includes suppression within protected areas that have generally been considered as safe havens. This review explores these tensions between the conservation of iconic and yet abundant wildlife, and conflict with people and the various interfaces at which they meet kangaroos.