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.
The low-elevation chaparral shrublands of southern California have long been occupied and modified by humans, but the magnitude and extent of human impact has dramatically increased since the early 1900s. As population growth started to boom in the 1940s, the primary form of habitat conversion transitioned from agriculture to urban and residential development. Now, urban growth is the primary contributor, directly and indirectly, to loss and fragmentation of chaparral landscapes. Different patterns and arrangements of housing development confer different ecological impacts. We found wide variation in the changing extent and pattern of development across the seven counties in the region. Substantial growth in lower-density exurban development has been associated with high frequency of human-caused ignitions as well as the expansion of highly flammable non-native annual grasses. Combined, increases in fire ignitions and the extent of grassland can lead to a positive feedback cycle in which grass promotes fire and shortens the fire-return interval, ultimately extirpating shrub species that are not adapted to short fire intervals. An overlay of a 1930s vegetation map with maps of contemporary vegetation showed a consistent trend of chaparral decline and conversion to sage scrub or grassland. In addition, those areas type-converted to grassland had the highest fire frequency over the latter part of the twentieth century. Thus, a continuing trend of population growth and urban expansion may continue to threaten the extent and intactness of remaining shrubland dominated landscapes. Interactions among housing development, fire ignitions, non-native grasses, roads, and vehicle emissions make fire prevention a complex endeavor. However, land use planning that targets the root cause of conversion, exurban sprawl, could address all of these threats simultaneously.
*Note: This publication comes from a book chapter from Biology and Conservation of Martens, Sables, and Fishers: A New Synthesis (1st edition).
Conservation and management of Martes populations are increasingly informed by quantitative models that predict habitat suitability and population viability. Recent modeling efforts to support fisher (Martes pennanti) reintroduction plan- ning in the state of Washington (USA) and conservation of an isolated fisher population in the southern Sierra Nevada (California, USA) have integrated re- sults from empirical static habitat models, such as resource-selection functions, with those from dynamic population-viability and vegetation models. Additional methods have been developed to identify habitat linkages with potential impor- tance for maintaining interpopulation dispersal. While such modeling frame- works can be useful in integrating data on species distribution, demography, and vegetation response to disturbance, the associated increased data requirements may also increase uncertainty regarding model projections to different places or times. The costs associated with reintroductions generally justify the use of such models to inform the planning process before substantial resources are commit- ted. Given the challenges posed by increasing human demands on forest ecosys- tems, well-constructed quantitative models can be key tools for enhancing the success of wildlife conservation efforts, as long as model uncertainty is consid- ered explicitly, and model results are used for informing decisions rather than predicting outcomes.
Fuzzy logic modeling is a useful method for evaluating landscapes for conservation and resource planning and has been successfully used in different types of ecological and environmental studies. A variety of software packages have been produced to facilitate fuzzy logic modeling, but each is either associated with a specific computer program or does not comprise a complete modeling system. The Environmental Evaluation Modeling System (EEMS) is a platform-independent fuzzy logic modeling framework for environmental decision support. EEMS has been designed so that it can easily be adapted to work with different file types and interface with other software systems. It has been implemented to work with NetCDF and CSV file formats as a command line application, in the ArcGIS ModelBuilder environment, and as part of a web-based data exploration tool. In a performance test, EEMS was run using a dataset with four million reporting units per map layer and yielded execution times of less than 30 s.Results from an EEMS model for Utah and the Colorado Plateau show a complex pattern of site sensitivity.
This article examines trends in farming and livelihood activities among forest-dwelling Adivasi farmers (Soligas) in a tiger reserve from 2008 to 2015. In-depth semistructured interviews were conducted in two contrasting, but representative, villages, where traditional mixed-crop farming was being replaced by cash crops such as coffee, maize, and cotton. Access to state-subsidized food supply and increase in cash income through wage labor, coupled with increasing depredation of food crops by wild animals, were some causes for the shift to cash crops. Declining supply of non-timber forest produce (NTFP) and the subsistence cash it provided has also impacted farmer livelihoods and indirectly contributed to this shift. The changing aspirations of younger Soligas and inadequate state support for mixed-crop farming also could be contributing factors. Soligas consistently maintained that increased wildlife depredation of food crops, reduction in supplies of wild foods, and the decline in NTFP was due to poor forest health. The transition to cash crops improved cash flows but exposed the Soligas to market risks. While food security also improved, the nutritional quality of diet declined. Soligas are adopting new farming practices, diets, and livelihood strategies, and importantly, leveraging rights historically denied to them, all a reflection of their social resilience.
Although wildfire plays an important role in maintaining biodiversity in many ecosystems, fire management to protect human assets is often carried out by different agencies than those tasked for conserving biodiversity. In fact, fire risk reduction and biodiversity conservation are often viewed as competing objectives. Here we explored the role of management through private land conservation and asked whether we could identify private land acquisition strategies that fulfill the mutual objectives of biodiversity conservation and fire risk reduction, or whether the maximization of one objective comes at a detriment to the other. Using a fixed budget and number of homes slated for development, we simulated 20 years of housing growth under alternative conservation selection strategies, and then projected the mean risk of fires destroying structures and the area and configuration of important habitat types in San Diego County, California, USA. We found clear differences in both fire risk projections and biodiversity impacts based on the way conservation lands are prioritized for selection, but these differences were split between two distinct groupings. If no conservation lands were purchased, or if purchases were prioritized based on cost or likelihood of development, both the projected fire risk and biodiversity impacts were much higher than if conservation lands were purchased in areas with high fire hazard or high species richness. Thus, conserving land focused on either of the two objectives resulted in nearly equivalent mutual benefits for both. These benefits not only resulted from preventing development in sensitive areas, but they were also due to the different housing patterns and arrangements that occurred as development was displaced from those areas. Although biodiversity conflicts may still arise using other fire management strategies, this study shows that mutual objectives can be attained through land-use planning in this region. These results likely generalize to any place where high species richness overlaps with hazardous wildland vegetation.
Seedling establishment is a critical step that may ultimately govern tree species’ distribution shifts under environmental change. Annual variation in the location of seed rain and microclimates results in transient “windows of opportunity” for tree seedling establishment across the landscape. These establishment windows vary at fine spatiotemporal scales that are not considered in most assessments of climate change impacts on tree species range dynamics and habitat displacement. We integrate field seedling establishment trials conducted in the southern Sierra Nevada and western Tehachapi Mountains of southern California with spatially downscaled grids of modeled water-year climatic water deficit (CWDwy) and mean August maximum daily temperature (Tmax) to map historical and projected future microclimates suitable for establishment windows of opportunity for Quercus douglasii, a dominant tree species of warm, dry foothill woodlands, and Q. kelloggii, a dominant of cooler, more mesic montane woodlands and forests. Based on quasi-binomial regression models, Q. douglasii seedling establishment is significantly associated with modeled CWDwy and to a lesser degree with modeled Tmax. Q. kelloggii seedling establishment is most strongly associated with Tmax and best predicted by a two-factor model including CWDwy and Tmax. Establishment niche models are applied to explore recruitment window dynamics in the western Tehachapi Mountains, where these species are currently widespread canopy dominants. Establishment windows are projected to decrease by 50–95%, shrinking locally to higher elevations and north-facing slopes by the end of this century depending on the species and climate scenario. These decreases in establishment windows suggest the potential for longer-term regional population declines of the species. While many additional processes regulate seedling establishment and growth, this study highlights the need to account for topoclimatic controls and interannual climatic variation when assessing how seedling establishment and colonization processes could be affected by climate change.