Variation in body size, especially mass, is a function of local environmental conditions for any given species. Recent recorded decreases in body size of endotherms have been attributed to climate change in some cases. This prediction is based on the trend of smaller body size of endotherms in warmer climates (Bergmann’s rule) and it implies genetic responses rather than phenotypic flexibility. Alternatively, selection for smaller body size or lower mass could be explained by the starvation-predation hypothesis, where lighter individuals have a higher probability of escaping pursuing predators, such as raptors. Evidence that climate warming is driving patterns of size selection in birds in recent times has been mixed. We inspected data on 40 bird species contributed by bird ringers to the South African Ringing Scheme (SAFRING) for changes in body mass and condition as a function of time (year), minimum temperature of the day of capture, maximum temperature of the previous day, and rainfall data in the south-western Cape Floristic Region (fynbos) around Cape Town, South Africa, for the period 1988–2015. The region shows a warming trend over the study period (0.035 °C yr−1). Interannual body mass and condition change were poorly explained by year or temperature. High daily minimum temperature explained loss of body condition for four species, whereas evidence from recaptured birds indicated negative effects of increasing maximum daily temperature, as well as rain. For the alternative hypothesis, because raptor abundance is stable or only weakly declining, there is little evidence to suggest these as a driver influencing mass trends. Any decrease in body mass over the study period that we observed for birds appear more likely to be plastic responses to stress associated with temperature or rainfall at this time, rather than systematic selection for smaller body size, as predicted by Bergmann’s Rule.
Ripple et al (BioScience 2020) We appreciate the letters by Pouliot and colleagues (2020) and DellaSala and colleagues (2020) about our recent article “World scientists’ warning of a climate emergency” (Ripple et al. 2020). Pouliot and colleagues (2020) call for more scientists, teachers, and citizens to become engaged advocates, and we agree on the importance of this in that failure of these groups to engage confirms the dangerous status quo that has led to our climate emergency. DellaSala and colleagues (2020) correctly point out that climate policymakers are focusing primarily on fossil fuels and ignoring the great importance of protecting the massive carbon stores in nature, especially the primary forests found from boreal to tropical regions. In Ripple and col- leagues (2020), we stressed the importance of scientists speaking out, telling it like it is, and becoming agents for change. We also emphasized that pre- serving and restoring nature is one of the six critical steps for mitigating the climate crisis.
At the World Economic Forum in January of 2020, world leaders committed to plant one trillion trees (1t.org). While tree planting is needed, this proposal also makes for good headlines for those who might assume they can then continue with business as usual. Planting trees will do little by itself to solve our climate emergency. A trillion trees do not make a for- est. Forests are complex ecosystems that depend on rich biodiversity of all types of species, from trees to bacteria and fungi, to be productive sinks and resilient reservoirs for carbon. Besides planting trees and regenerating natural forest habitats, we urgently need to curb the rate of global deforestation. Nature-based solutions should become a major focus of climate policy. Forests could store substantially more carbon if allowed to grow and reach their ecological potential (Erb et al. 2018). Preserving our current primary forests and allowing secondary forests to grow for carbon storage would increase car- bon sinks in the near and intermediate future (proforestation; Moomaw et al. 2019). This would benefit biodiversity and watershed protection much more than planting a trillion trees that will take many decades to effectively remove atmospheric carbon dioxide (Law et al. 2018, Buotte et al. 2019).
Nature-based solutions span numerous ecosystems including forests, wetlands, grasslands, peatlands, mangroves, and others. Their biological processes include carbon uptake and storage in vegetation and soils. Therefore, active engagement with decision makers to instigate and incentivize regenerative land uses, reform food systems, and preserve and restore ecosystems is needed to increase carbon storage, while help- ing meet multiple policy goals (e.g., biodiversity, food security, water security, economic diversification). To make a difference at the spatial and economic scales necessary to achieve effective climate change mitigation, it is vital that nature-based solutions receive global backing from diverse groups of individuals and institutions, including scientists, Indigenous people, policymakers, businesses, and land owners. Given the potential co-benefits of focusing on nature to address climate change, we are confident they can gain broad-scale support, provided they are developed and implemented in an equitable way that promotes social and environmental justice. It is essential that a combined effort to reduce emissions from the energy and industrial sector, land use changes, and agriculture be combined with protect- ing natural systems from degradation and deforestation and restoring those that have been damaged. While plant- ing trees is a laudable effort, we need to bring greenhouse gas emissions close to zero as rapidly as possible and restore and nurture functioning ecosystems, which support all life on Earth and are a prerequisite for human existence.
The increasing threat of irreversible catastrophic climate change must compel immediate and immense action across all scales of society. Irreversible climate tipping points are too risky for us to continue conducting business as usual (Lenton et al. 2019). We agree strongly with Pouliot and colleagues (2020) that scientists, teachers, and citizens must boldly address climate change by taking the actions necessary to avoid the otherwise inevitable consequences. We need transformative change in how we mitigate and adapt to the climate crisis. This will entail massive personal, societal, and global political adjustments in how we function on our finite and now damaged planet in terms of energy, pollution, nature, food, economy, and human population issues (for an expanded discussion, see Ripple et al. 2020). These changes must be folded into the fabric of social and economic justice for all. We now need many more scientists to enter the science–policy– practice arena, because time is short. The transformations that we call for will at times be uncomfortable, unsettling, and strongly opposed by powerful economic and political forces. But, change can only follow when we first shift our vision to what is not only possible, but also critical for the future of Earth’s ecosystems and humanity’s survival.
Scientists can become signatories of the paper “World scientists’ warning of a climate emergency” at https://scientistswarning.forestry.oregonstate.edu/
Scientists have a moral obligation to clearly warn humanity of any catastrophic threat and to “tell it like it is”. On the basis of this obligation and the graphical indicators presented below, we declare, with more than 11,000 scientist signatories from around the world, clearly and unequivocally that planet Earth is facing a climate emergency.
Exactly 40 years ago, scientists from 50 nations met at the First World Climate Conference (in Geneva 1979) and agreed that alarming trends for climate change made it urgently necessary to act. Since then, similar alarms have been made through the 1992 Rio Summit, the 1997 Kyoto Protocol, and the 2015 Paris Agreement, as well as scores of other global assemblies and scientists’ explicit warnings of insufficient progress (Ripple et al. 2017). Yet greenhouse gas (GHG) emissions are still rapidly rising, with increasingly damaging effects on the Earth’s cli- mate. An immense increase of scale in endeavors to conserve our biosphere is needed to avoid untold suffering due to the climate crisis (IPCC 2018).
The purpose of this research is to better conserve biodiversity by improving land allocation modeling software. Here we introduce a planning support framework designed to be understood by and useful to land managers, stakeholders, and other decision-makers. With understanding comes trust and engagement, which often yield better implementation of model results. To do this, we break from traditional software such as Zonation and Marxan with Zones to prototype software that instead first asks the project team and stakeholders to make a straightforward multi-criteria decision tree used for traditional site evaluation analyses. The results can be used as is or fed into an algorithm for identifying a land allocation solution that is efficient in meeting several objectives including maximizing habitat representation, connectivity, and adjacency at a set cost budget. We tested the framework in five pilot regions and share the lessons learned from each, with a detailed description and evaluation of the fifth (in the central Sierra Nevada mountains of California) where the software effectively met the multiple objectives, for multiple zones (Restoration, Innovation, and Observation Zones). The framework is sufficiently general that it can be applied to a wide range of land use planning efforts.
This article was chosen as one of the Editor’s Choice Articles of Section “Landscape Ecology” in 2020 and 2021. https://www.mdpi.com/about/announcements/4677
Sagebrush ecosystems have endured fragmentation and degradation from multiple disturbances. Climate change poses an additional threat that can exacerbate current stresses. Web-based climate applications can provide information to help land managers prepare for challenges. To develop useful and usable tools for land managers’ needs, the collaboration of scientist, web tool developer, and user is needed. Climate scientists and web tool developers at Conservation Biology Institute (CBI) worked with Oregon and Idaho Bureau of Land Management (BLM) sagebrush land managers assessing managers’ needs and defining criteria for useful and usable web-based climate applications. During phone interviews, land managers evaluated a series of climate related web applications and provided insight on how future applications can best meet their needs. They identified climate variables associated with their management activities, such as the seasonality of precipitation and temperature. They provided feedback about website accessibility, terminology, climate model description, spatial and temporal scale appropriateness, graphics effectiveness, and general content credibility and consistency. Managers are interested in changes in climate, but also in climate change impacts, such as vegetation shifts. Managers need seasonal and multiannual weather forecasts for routine activities and 10–20-yr climate projections for planning exercises, but currently an information gap exists between available weather forecasts (#12 months) and climate projections (30-yr averages). It was also found that scientific jargon contributes to misunderstandings and misinterpretation of climate information, and this study confirmed the need for better climate science education, through enhanced explanation and collaborative efforts that promote understanding and use of existing web applications.
The MC2 model projects an overall increase in carbon capture in conterminous United States during the 21st century while also simulating a rise in fire causing much carbon loss. Carbon sequestration in soils is critical to prevent carbon losses from future disturbances, and we show that natural ecosystems store more carbon belowground than managed systems do. Natural and human-caused disturbances affect soil processes that shape ecosystem recovery and competitive interactions between native, exotics, and climate refugees. Tomorrow’s carbon budgets will depend on how land use, natural disturbances, and climate variability will interact and affect the balance between carbon capture and release.
This book chapter titled “Tryst with Lantana camara” is included in the book Transcending Boundaries: Reflecting on twenty years of action and research at ATREE” and was co-written by CBI’s Chief Project Officer Dr. Gladwin Joseph. Dr. Joseph also serves as an adjunct senior fellow at ATREE (Ashoka Trust for Research in Ecology and the Environment), an India based non-profit working to conserve India’s biodiversity.
The Anthropocene presents society with a super wicked problem comprised of multiple contingent and conflicting issues driven by a complex array of change agents. Super wicked problems cannot be adequately addressed using siloed decision-making approaches developed by hierarchical institutions using science that is compartmentalized by discipline. Adaptive solutions will rest on human ingenuity that fosters transformation towards sustainability. To successfully achieve these objectives, conservation and natural resource practitioners need a paradigm that transcends single-institution interests and decision-making processes. We propose a platform for an emerging and evolutionary step change in sustainability planning: landscape conservation design (LCD). We use existing governance and adaptation planning principles to develop an iterative, flexible innovation systems framework—the “iCASS Platform.” It consists of nine principles and five attributes—innovation, convening stakeholders, assessing current and plausible future landscape conditions, spatial design, and strategy design. The principles are organized around four cornerstones of innovation: people, purpose, process, and product. The iCASS Platform can facilitate LCD via processes that aim to create and empower social networks, foster stakeholder involvement, engender co-production and cross-pollination of knowledge, and provide multiple opportunities for deliberation, transparency, and collaborative decision-making. Our intention is to pivot from single-institution, siloed assessment and planning to stakeholder-driven, participatory design, leading to collaborative decision-making and extensive landscape conservation.
Mediterranean-climate natural systems have high ecological value, yet the extent of their cover has diminished greatly due to changes in land use. Other stressors, ranging from intense short- term disturbances such as wildfire to more gradual events such as extended drought and continuous pressures including competition with invasive species, test the resistance and resilience of community composition and structure. Data from long-term monitoring provided an opportunity to evaluate the responses of three Southern California plant communities (chaparral, coastal sage scrub, and grass- land) to disturbances. We analyzed ten years of point intercept and quadrat data from Orange County to describe trends through time and assess community resistance and resilience. We found that grass- land communities, which were more degraded from the start of our study, were generally resistant to change. Chaparral was also fairly resistant to disturbance, while coastal sage scrub exhibited more variation, with some transects exhibiting more resilience than others. Transects with fewer native shrubs experienced less of a decline in shrub cover during drought than those with dense shrubs. Grasslands had the lowest native diversity. There were increases in native diversity in years with more precipitation that were preceded by dry years. There was a decline in native perennial bunch- grasses during our monitoring. Our analyses demonstrated the resilience of native shrub cover to fire and the susceptibility (low resistance) of dense native shrubs and native grasses to drought and increases in non-native species. We encourage academic ecologists to embrace diverse data sources available for hypothesis testing, especially monitoring efforts associated with regulatory purposes, to advance the goal of understanding long-term dynamics.
The size of the hippocampus, a forebrain structure that processes spatial information, correlates with the need to relocate food caches by passerine birds and with sex-specific patterns of space use in microtine rodents. The influences on hippocampal anatomy of sexual selection within species, and natural selection between species, have not yet been studied in concert, however. Here we report that natural space-use patterns predict hippocampal size within and between two species of kangaroo rats (Dipodomys). Differences in foraging behavior suggest that Merriam’s kangaroo rats (D. merriami) require better spatial abilities than bannertail kangaroo rats (D. spectabilis). Sex-specific differences in mating strategy suggest that males of both species require more spatial ability than females. As predicted, hippocampal size (relative to brain size) is larger in Merriam’s than in bannertail kangaroo rats, and males have larger hippocampi than females in both species. Males of a third species (D. ordii) also have smaller hippocampi than Merriam’s kangaroo rat males, despite being similar to Merriam’s in brain and body size. These results suggest that both natural and sexual selection affect the relative size and perhaps function of mammalian hippocampi. They also reassert that measures of functional subunits of the brain reveal more about brain evolution than measures of total brain size.