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There is increasing interest in using “real-world pedagogy” to train students in ways that make them better able to contribute toward a more sustainable society. While there is a robust body of literature on the competencies that students need as sustainability professionals, there is a lack of specific guidance in the literature on how to teach for competency development or on how to structure a program or course to support competency development. Our research addresses this gap in the literature through a description and autoethnographic reflection on the design and early implementation of a “real-world” course. The course is from the Environmental Studies Program at Dartmouth College (Hanover, NH, USA), but it takes place in the environs of the Gobabeb Research and Training Centre in the Namib Desert of Namibia and in nearby Topnaar settlements. Our research objective was to articulate strategies to address the primary pedagogical challenges that we faced during the design and first five iterations of the course. These include: How do we frame this course and communicate it to students in a way that is understandable and works within the particular context and constraints of the course? Can we provide students with a coherent framework that helps them to understand the approach and also provides a platform for thoughtful consideration, acquisition, and retention of appropriate competencies? How do we develop collaborations with our community partners that are ethical and effective? How do we frame these real-world experiences in a way that allows for students to integrate their experience with the theory and broader empiricism they learn on campus? To address these pedagogic challenges, we framed the course as a research-based course, more specifically community-based research (CBR), conducted in a social-ecological system (SES). We developed lower-level strategies for implementing this framing, including preparing students for collaborative research, encouraging student ownership of their learning, linking theory to research, and thoughtfully navigating time constraints. Furthermore, program-level and student-level engagement with community have been critical for avoiding becoming “helicopter researchers.” Drawing on our personal reflections and those of our community partners, we conclude with a discussion of emergent outcomes and the next steps for continual improvement and adaptation.
Douglas T. Bolger; Karen Hutchins Bieluch; Flora E. Krivak-Tetley; Gillian Maggs-Kölling; Joseph Tjitekulu. Designing a Real-World Course for Environmental Studies Students: Entering a Social-Ecological System. Sustainability 2018, 10, 2546 .
AMA StyleDouglas T. Bolger, Karen Hutchins Bieluch, Flora E. Krivak-Tetley, Gillian Maggs-Kölling, Joseph Tjitekulu. Designing a Real-World Course for Environmental Studies Students: Entering a Social-Ecological System. Sustainability. 2018; 10 (7):2546.
Chicago/Turabian StyleDouglas T. Bolger; Karen Hutchins Bieluch; Flora E. Krivak-Tetley; Gillian Maggs-Kölling; Joseph Tjitekulu. 2018. "Designing a Real-World Course for Environmental Studies Students: Entering a Social-Ecological System." Sustainability 10, no. 7: 2546.
Examination of spatial variation in demography among or within populations of the same species is a topic of growing interest in ecology. We examined whether spatial variation in demography of a tropical megaherbivore followed the “temporal paradigm” or the “adult survival paradigm” of ungulate population dynamics formulated from temperate-zone studies. We quantified spatial variation in demographic rates for giraffes (Giraffa camelopardalis) at regional and continental scales. Regionally, we used photographic capture-mark-recapture data from 860 adult females and 449 calves to estimate adult female survival, calf survival, and reproduction at 5 sites in the Tarangire ecosystem of Tanzania. We examined potential mechanisms for spatial variation in regional demographic rates. At the continental scale, we synthesized demographic estimates from published studies across the range of the species. We created matrix population models for all sites at both scales and used prospective and retrospective analyses to determine which vital rate was most important to variation in population growth rate. Spatial variability of demographic parameters at the continental scale was in agreement with the temporal paradigm of low variability in adult survival and more highly variable reproduction and calf survival. In contrast, at the regional scale, adult female survival had higher spatial variation, in agreement with the adult survival paradigm. At both scales, variation in adult female survival made the greatest contribution to variation in local population growth rates. Our work documented contrasting patterns of spatial variation in demographic rates of giraffes at 2 spatial scales, but at both scales, we found the same vital rate was most important. We also found anthropogenic impacts on adult females are the most likely mechanism of regional population trajectories.
Derek E. Lee; Monica Bond; Bernard M. Kissui; Yustina A. Kiwango; Douglas T. Bolger. Spatial variation in giraffe demography: a test of 2 paradigms. Journal of Mammalogy 2016, 97, 1015 -1025.
AMA StyleDerek E. Lee, Monica Bond, Bernard M. Kissui, Yustina A. Kiwango, Douglas T. Bolger. Spatial variation in giraffe demography: a test of 2 paradigms. Journal of Mammalogy. 2016; 97 (4):1015-1025.
Chicago/Turabian StyleDerek E. Lee; Monica Bond; Bernard M. Kissui; Yustina A. Kiwango; Douglas T. Bolger. 2016. "Spatial variation in giraffe demography: a test of 2 paradigms." Journal of Mammalogy 97, no. 4: 1015-1025.
The hyper-abundance of migratory wildlife in many ecosystems depends on maintaining access to seasonally available resources. In Eastern and Southern Africa, land-use change and a loss of connectivity have coincided with widespread declines in the abundance and geographic range of ungulate populations. Using photographic capture-mark-recapture, we examine the historical pattern of loss of connectivity and its impact on population trends in a partially migratory wildebeest population in northern Tanzania. To estimate abundance, we use a novel modeling approach that overcomes bias associated with photo misidentifications. Our data indicate (1) diminished connectivity within and between seasonal areas as a result of human activities, (2) a reduction in the overall population size compared to historical numbers, with high variability over time, (3) the continued use of highly constrained movement corridors between the three main seasonal ranges, (4) higher recruitment in the non-migratory subpopulation (Lake Manyara National Park) than in other areas of the ecosystem, and (5) an increase in the relative abundance of resident to migrant wildebeest. Recent conservation efforts to protect seasonal habitat and to enforce anti-poaching policies outside protected areas have likely helped stabilize the population, at least temporarily, but we caution that several key vulnerabilities remain.
Thomas A. Morrison; William A. Link; William D. Newmark; Charles A.H. Foley; Douglas T. Bolger. Tarangire revisited: Consequences of declining connectivity in a tropical ungulate population. Biological Conservation 2016, 197, 53 -60.
AMA StyleThomas A. Morrison, William A. Link, William D. Newmark, Charles A.H. Foley, Douglas T. Bolger. Tarangire revisited: Consequences of declining connectivity in a tropical ungulate population. Biological Conservation. 2016; 197 ():53-60.
Chicago/Turabian StyleThomas A. Morrison; William A. Link; William D. Newmark; Charles A.H. Foley; Douglas T. Bolger. 2016. "Tarangire revisited: Consequences of declining connectivity in a tropical ungulate population." Biological Conservation 197, no. : 53-60.
1. Photographic mark–recapture is a cost‐effective, non‐invasive way to study populations. However, to efficiently apply photographic mark–recapture to large populations, computer software is needed for image manipulation and pattern matching. 2. We created an open‐source application for the storage, pattern extraction and pattern matching of digital images for the purposes of mark–recapture analysis. The resulting software package is a stand‐alone, multiplatform application implemented in Java. Our program employs the Scale Invariant Feature Transform (SIFT) operator that extracts distinctive features invariant to image scale and rotation. 3. We applied this system to a population of Masai giraffe (Giraffa camelopardalis tippelskirchi) in the Tarangire Ecosystem in northern Tanzania. Over 1200 images were acquired in the field during three primary sampling periods between September 2008 and December 2009. The pattern information in these images was extracted and matched resulting in capture histories for over 600 unique individuals. 4. Estimated error rates of the matching system were low based on a subset of test images that were independently matched by eye. 5. Encounter histories were subsequently analysed with open population models to estimate apparent survival rates and population size. 6. This new open‐access tool allowed photographic mark–recapture to be applied successfully to this relatively large population.
Douglas T. Bolger; Thomas A. Morrison; Bennet Vance; Derek Lee; Hany Farid. A computer-assisted system for photographic mark-recapture analysis. Methods in Ecology and Evolution 2012, 3, 813 -822.
AMA StyleDouglas T. Bolger, Thomas A. Morrison, Bennet Vance, Derek Lee, Hany Farid. A computer-assisted system for photographic mark-recapture analysis. Methods in Ecology and Evolution. 2012; 3 (5):813-822.
Chicago/Turabian StyleDouglas T. Bolger; Thomas A. Morrison; Bennet Vance; Derek Lee; Hany Farid. 2012. "A computer-assisted system for photographic mark-recapture analysis." Methods in Ecology and Evolution 3, no. 5: 813-822.
Habitat fragmentation and invasive species often contribute to the decline of native taxa. Since the penetration of non‐native species into natural habitat may be facilitated by habitat fragmentation, it is important to examine how these two factors interact. Previous research documented that, in contrast to most other arthropod taxa, spiders increased in density and morphospecies richness with decreasing fragment area and increasing fragment age (time since insularization) in urban habitat fragments in San Diego County, California, USA. We tested whether a specific mechanism, an increase in non‐native species with fragmentation, is responsible for this pattern. We found that both native and non‐native taxa contributed to the pattern. Abundance of native spiders per pitfall trap sample increased significantly with decreasing fragment size (i.e. a negative density–area relationship) and abundance of non‐natives increased significantly with increasing fragment age. The proportion of non‐native individuals also increased significantly with age. One non‐native species, Oecobius navus, comprised the majority of non‐native individuals (82.2%) and a significant proportion of total individuals (25.1%). Richness of spider families per sample (family density) increased with fragment age due to an increase in the occurrence of non‐natives in older fragments, however, native family richness did not vary with age or area. Due to increasing dominance by non‐native and some native families, family evenness declined with decreasing fragment size and increasing fragment age. Native and non‐native abundance covaried positively arguing against strong negative interactions between the two groups. O. navus had a strong positive association with another common non‐native arthropod, the Argentine ant (Linepitheme humile), suggesting a possible direct interaction. In contrast, abundance of native spiders was negatively correlated with Argentine ant abundance. We hypothesize that fragmentation in this semiarid habitat increases productivity in smaller and older fragments enhancing the density of both native and non‐native taxa.
Douglas T. Bolger; Karen H. Beard; Andrew V. Suarez; Ted J. Case. Increased abundance of native and non-native spiders with habitat fragmentation. Diversity and Distributions 2008, 14, 655 -665.
AMA StyleDouglas T. Bolger, Karen H. Beard, Andrew V. Suarez, Ted J. Case. Increased abundance of native and non-native spiders with habitat fragmentation. Diversity and Distributions. 2008; 14 (4):655-665.
Chicago/Turabian StyleDouglas T. Bolger; Karen H. Beard; Andrew V. Suarez; Ted J. Case. 2008. "Increased abundance of native and non-native spiders with habitat fragmentation." Diversity and Distributions 14, no. 4: 655-665.
Over the last two centuries overhunting, anthropogenic barriers and habitat loss have disrupted many ungulate migrations. We review the literature on ungulate migration disruptions and find that for many species the disruption of migratory routes causes a rapid population collapse. Previous research has focused on the proximal ecological factors that might favour migration, particularly spatiotemporal variation in resources and predation. However, this does not provide an adequate basis for understanding and mitigating anthropogenic effects on migratory populations. Migration is a complex behaviour and we advocate an integrative approach that incorporates population dynamics, evolution, genetics, behaviour and physiology, and that borrows insights and approaches from research on other taxa. We draw upon research on avian migration to illustrate research approaches that might also be fruitful in ungulates. In particular, we suggest that the migratory cycle should be evaluated in the context of seasonal population limitation, an approach we highlight with a preliminary demographic perturbation analysis of the Serengeti wildebeest (Connochaetes taurinus) population. We provide suggestions for avenues of future research and highlight areas where we believe rapid progress can be made by applying recent advances in theory, technology and analytical approaches.
Douglas T. Bolger; William D. Newmark; Thomas A. Morrison; Daniel F. Doak. The need for integrative approaches to understand and conserve migratory ungulates. Ecology Letters 2007, 11, 63 -77.
AMA StyleDouglas T. Bolger, William D. Newmark, Thomas A. Morrison, Daniel F. Doak. The need for integrative approaches to understand and conserve migratory ungulates. Ecology Letters. 2007; 11 (1):63-77.
Chicago/Turabian StyleDouglas T. Bolger; William D. Newmark; Thomas A. Morrison; Daniel F. Doak. 2007. "The need for integrative approaches to understand and conserve migratory ungulates." Ecology Letters 11, no. 1: 63-77.
Recently, climate change research has emphasized the potential increase in the frequency and severity of climatic extremes. We compared the reproductive effort and output among four species of passerine birds in coastal southern California, USA, a semi-arid region, during a normal precipitation year (2001) and the driest year in a 150-year climate record (2002). Both reproductive effort and output differed dramatically between years. Mean reproductive output among the four species was 2.37 fledglings/pair in 2001 and 88.4% of all pairs observed attempted at least one nest. The birds attempted a mean of 1.44 nests per pair and were successful in 47.7% of those attempts. In 2002, only 6.7% of the pairs even attempted a nest and only 1.8% were successful, for a total output of 0.07 fledglings per pair. The abundance of suitable arthropod prey items in the environment was also much lower in 2002, suggesting that low food availability was the proximal cause of the reproductive failure. The data for one of these species, the rufous-crowned sparrow (Aimophila ruficeps), were combined with reproductive and rainfall data from a previous 3-year study (1997–1999) in the same sites. The combined data sets suggest that the response of reproduction to rainfall variation is linear, and that the low end of the precipitation range brings the population near reproductive failure. Any change in climate that would increase the frequency of extreme dry conditions would likely endanger populations of these species.
Douglas T. Bolger; Michael A. Patten; David C. Bostock. Avian reproductive failure in response to an extreme climatic event. Oecologia 2004, 142, 398 -406.
AMA StyleDouglas T. Bolger, Michael A. Patten, David C. Bostock. Avian reproductive failure in response to an extreme climatic event. Oecologia. 2004; 142 (3):398-406.
Chicago/Turabian StyleDouglas T. Bolger; Michael A. Patten; David C. Bostock. 2004. "Avian reproductive failure in response to an extreme climatic event." Oecologia 142, no. 3: 398-406.
We used point-count and transect surveys to estimate the distribution and abundance of eight scrub-breeding bird species in 34 habitat fragments and the urban matrix in southern California. We then calculated local extinction and colonization rates by comparing our data with surveys conducted in 1987. We classified factors that influence extinction and colonization rates into two types: (1) extrinsic factors, which are characteristics of the habitat fragments such as area, age, and isolation and (2) intrinsic factors, which are characteristics of the species that inhabit fragments, such as body size and population density. Over the past decade, at least one species went locally extinct in over 50% of the fragments, and local extinc- tions were almost twice as common as colonizations. Fragment size and, to a lesser extent, fragment age were the most important extrinsic factors determining extinction and colonization. Density indices of scrub birds were the most important intrinsic factors determining extinction rates, predicting the number of sites occupied, the probability of local extinction, relative area requirements, and time to local extinction.
Kevin R. Crooks; Andrew V. Suarez; Douglas T. Bolger; Michael E. Soulé. Extinction and Colonization of Birds on Habitat Islands. Conservation Biology 2001, 15, 159 -172.
AMA StyleKevin R. Crooks, Andrew V. Suarez, Douglas T. Bolger, Michael E. Soulé. Extinction and Colonization of Birds on Habitat Islands. Conservation Biology. 2001; 15 (1):159-172.
Chicago/Turabian StyleKevin R. Crooks; Andrew V. Suarez; Douglas T. Bolger; Michael E. Soulé. 2001. "Extinction and Colonization of Birds on Habitat Islands." Conservation Biology 15, no. 1: 159-172.
We investigated the roles of habitat fragmentation and the invasion of an exotic species on the structure of ground‐foraging ant communities in 40 scrub habitat fragments in coastal southern California. In particular, we asked: how do fragment age, fragment size, amount of urban edge, percentage of native vegetation, degree of isolation, and the relative abundance of an exotic species, the Argentine ant (Linepithema humile) affect native ants? Within these fragments, Argentine ants were more abundant near developed edges and in areas dominated by exotic vegetation. The number of native ground‐foraging ant species at any point declined from an average of >7 to <2 species in the presence of the Argentine ant. Among fragments, a stepwise multiple regression revealed that the abundance of Argentine ants, the size of the fragment, and the number of years since it was isolated from larger continuous areas of scrub habitat best predict the number of remaining native ant species. The Argentine ant was found in every fragment surveyed as well as around the edges of larger unfragmented areas. Fragments had fewer native ant species than similar‐sized plots within large unfragmented areas, and fragments with Argentine ant‐free refugia had more native ant species than those without refugia. The relative vulnerability of native ants to habitat fragmentation and the subsequent presence of Argentine ants vary among species. The most sensitive species include army ants (Neivamyrmex spp.) and harvester ants (genera Messor and Pogonomyrmex), both of which are important to ecosystem‐level processes. Our surveys suggest that the Argentine ant is widespread in fragmented coastal scrub habitats in southern California and strongly affects native ant communities.
Andrew V. Suarez; Douglas T. Bolger; Ted J. Case. EFFECTS OF FRAGMENTATION AND INVASION ON NATIVE ANT COMMUNITIES IN COASTAL SOUTHERN CALIFORNIA. Ecology 1998, 79, 2041 -2056.
AMA StyleAndrew V. Suarez, Douglas T. Bolger, Ted J. Case. EFFECTS OF FRAGMENTATION AND INVASION ON NATIVE ANT COMMUNITIES IN COASTAL SOUTHERN CALIFORNIA. Ecology. 1998; 79 (6):2041-2056.
Chicago/Turabian StyleAndrew V. Suarez; Douglas T. Bolger; Ted J. Case. 1998. "EFFECTS OF FRAGMENTATION AND INVASION ON NATIVE ANT COMMUNITIES IN COASTAL SOUTHERN CALIFORNIA." Ecology 79, no. 6: 2041-2056.
Ted J. Case; Douglas T. Bolger; Kenneth Petren. Invasions and Competitive Displacement among House Geckos in the Tropical Pacific. Ecology 1994, 75, 464 -477.
AMA StyleTed J. Case, Douglas T. Bolger, Kenneth Petren. Invasions and Competitive Displacement among House Geckos in the Tropical Pacific. Ecology. 1994; 75 (2):464-477.
Chicago/Turabian StyleTed J. Case; Douglas T. Bolger; Kenneth Petren. 1994. "Invasions and Competitive Displacement among House Geckos in the Tropical Pacific." Ecology 75, no. 2: 464-477.