Posters

Papers A-G | Papers H-N | Papers O-Z | Posters

Title:	Watershed restoration: A case study of limiting factors vs. local realities in the Russian River watershed
Author:	Juliet Christian-Smith, University of California at Berkeley
Format:	poster
Presentation:	Poster Session, 5:30 - 6:30 pm, Atrium
Abstract:	Restoration ecology has grown remarkably in the last decade in response to growing concerns regarding the long-term negative impacts of many human activities on natural resources. Billions of dollars are being spent on the restoration of land and water resources in the United States. This restoration is done with the goal of returning some degree of ecological functioning to a system, yet it is still unclear how often restoration is successful in this pursuit. In the Russian River watershed, public agencies published a report to identify limiting factors for endangered salmonids in tributaries throughout the watershed. Yet through a spatial analysis of restoration projects undertaken in the Russian River basin within the last 5 years, one finds little correlation between the location of restoration projects and corresponding limiting factors. In other words, there is no clear relationship between where streams have been identified as in need of restoration for specific limiting factors and where restoration to address those factors actually occurs. The dichotomy between ecologically defined restoration need and actual restoration project implementation clearly indicates that other factors are at work in prioritizing and implementing restoration projects along the Russian River. It is crucial to identify the factors that are, in reality, instrumental in driving restoration in the Russian River basin to increase our understanding of restoration as a theory and provide information that can improve the effectiveness of restoration in practice. Other factors that are examined in relation to actual restoration project location are average population density, average lot size, median income, political boundaries, local capacity, and development pressure. This study marks the beginning of a larger investigation of the social and economic factors that influence restoration in the Russian River watershed.

Title:	Diet for an endangered insect: What does the Zayante band-winged grasshopper eat?
Author:	Jennifer Chu, San Jose State University Rachel O'Malley, San Jose State University
Format:	poster
Presentation:	Poster Session, 5:30 - 6:30 pm, Atrium
Abstract:	One of the greatest challenges to protecting and restoring habitat for endangered invertebrates is insufficient basic life history and ecological information. Collecting such data for rare species is especially challenging because most host plant identification protocols involve destructive sampling, such as gut content analysis, that are inappropriate for endangered species. This study used a combination of frass analysis, field observations, and habitat use correlations to infer host plant use and preference for adult Zayante band-winged grasshopper (ZBWG) Trimerotropis infantilis (Orthoptera: Acrididae) in Santa Cruz County, California. Of 128 frass samples collected, host plant identity could be clearly determined through microscopic analysis in 103 samples. The majority of host plants found in the frass were Lupinus albifrons (Fabaceae) and Heterotheca sessiliflora (Asteraceae), with occasional evidence of the use of species in Poaceae. Results from frass analysis corresponded with data obtained through 33 hours of field observation. Habitat choice by T. infantilis did not correlate well with host plant choice, however. This result suggests that factors other than food source in the plant community, such as cover from predation or support of courtship and mating, may be important to ZBWG life history and fitness. Work was conducted at Quail Hollow Quarry, Santa Cruz. During the spring and summer of 2001, with laboratory work completed during the winter months of 2001-2002. Results will be used in to help identify critical plant species needed for the protection of the species.

Title:	Distribution of native and introduced bird species in the UC Berkeley Botanical Garden: GIS analysis of habitat preferences
Author:	Christopher Colvin, University of California at Berkeley Meiling Cabral, University of California at Berkeley Elisa Fanchiang, University of California at Berkeley Nick Foster-Mann, University of California at Berkeley Madhuri Sudan, University of California at Berkeley William Monahan, University of California at Berkeley
Format:	poster
Presentation:	Poster Session, 5:30 - 6:30 pm, Atrium
Abstract:	Urbanization often presents challenges for the native flora and fauna of a region. These challenges can take the form of introduced predators and competitors, diseases, and/or loss of suitable habitat. Our objective was to quantitatively assess habitat preferences of native and introduced bird species in the presence of native and exotic vegetation as well as major edges (roads and buildings). We counted and mapped the positions of 21 bird species common to the UC Botanical Garden, obtaining >35 detections for each of 4 focal species: Steller's Jay (Cyanocitta stelleri), Dark-eyed Junco (Junco hyemalis), California Towhee (Pipilo crissalis), and the introduced House Sparrow (Passer domesticus). We predicted native birds to be found closer to native vegetation zones than expected by chance. The House Sparrow, however, was expected to reside closer to major edges than expected by chance. Spatial analysis confirmed the House Sparrow as an edge specialist (Kolmogorov-Smirnov two-sample test, p<0.05). Of native birds, only the California Towhee was non-randomly distributed, residing significantly further from native areas than expected by chance (Kolmogorov-Smirnov two-sample test, p<0.05). Results indicate that pockets of exotic vegetation are not inherently unsuitable to certain native birds in the Bay Area.

Title:	Using fecal DNA to examine dispersal and gene flow between populations of desert bighorn sheep
Author:	Clinton Epps, University of California at Berkeley
Format:	poster
Presentation:	Poster Session, 5:30 - 6:30 pm, Atrium
Abstract:	More than 50 extant populations of desert bighorn sheep inhabit small discrete mountain ranges in the desert regions of California in the western United States. Most populations are small and isolated from other populations by inter-mountain desert flats lacking suitable escape terrain and forage. However, occasional inter-population movements do occur. Female movement is of particular interest as females tend to be more philopatric, and are necessary for successful colonization of empty habitat patches. I collected fecal samples from 16 populations in the central Mojave Desert, using a combination of observation at waterholes and microsatellite analysis to identify individuals. I sequenced a 680 base-pair fragment of mitochondrial control region from each individual’s fecal sample. Substantial variation in haplotype distribution and frequency was observed even over distances of a few kilometers. A likely source population was identified for two recent colonizations of empty habitat patches in the area. This information will allow better understanding of metapopulation structure of a large mammal that has an extremely fragmented natural distribution. The use of non-invasive sampling allowed very large sample sizes to be collected in each population without the expense and trauma of live capture.

Title:	Seed dispersal of Umbellularia californica and other trees by Western Gray squirrels
Author:	Michael Faden, San Francisco State University
Format:	poster
Presentation:	Poster Session, 5:30 - 6:30 pm, Atrium
Abstract:	Western Gray Squirrels (Sciurus griseus) act as seed dispersers in mixed-evergreen forest in Marin County, Ca., by caching seeds of several tree species, including oaks and California bay-laurel (Umbellularia californica), a behavior known as scatterhoarding. This study focuses primarily on caching of Umbellularia seeds in order to examine factors that affect caching rates, seed dispersal distance and survival to germination. Early results suggest that dispersal distance and seed survival are influenced by the abundance or rarity of the species whose seeds are scatterhoarded. Squirrels generally buried seeds singly in shallow caches 1m-30m from the seed source, within forest patches but not in open grassland, suggesting that habitat fragmentation may restrict their ability to act as dispersers. Burial appeared essential for germination of Umbellularia seeds. The study suggests scatterhoarding by squirrels is an important dispersal mechanism that influences community structure in coastal forests.

Title:	Correlations between historic land-use and physical characteristics of Massachusetts forests: A tool for conservation planning
Author:	Joel Gerwein, University of Massachusetts at Boston
Format:	poster
Presentation:	Poster Session, 5:30 - 6:30 pm, Atrium
Abstract:	The land-use history of an area has significant long-term effects on its biological community. This study examines the correlations between the location of large and small forest patches in 1830 and soil quality, slope, elevation and aspect for 28 towns in central and western Massachusetts. Town maps from 1830 were used to reconstruct forest cover and landscape structure around peak deforestation, while modern digital coverages were used to determine physical site characteristics. Compared to small forest patches and open land, large forest patches were at significantly higher elevations, on significantly steeper slopes, more likely to have a western aspect, and on soils ranked as significantly less suitable for pasture. Compared to large forest patches, open land and small forest patches were more likely to be located on flat land with no appreciable aspect. Compared to open land, small forest patches were located at significantly lower elevations and were ranked as significantly less suitable for pasture. Town-level analysis showed that towns with greater mean slopes and more unfavorable aspects (N, NW, W) were more forested in 1830. All of these findings suggest simply that farmers tended to clear land that was better suited to agriculture. Regional conservation planners interested in protecting large forest patches that were never cleared for agriculture should focus on high elevation land with steep slopes and unfavorable aspects and soils. These results are valuable for planning on a landscape scale, and for understanding the significance of individual sites within the larger landscape. However, they do not constitute broadly applicable rules. Studies of this type in other regions would be valuable to conservation planners, ecologists and all who want to understand the imprint that human land-use leaves on the landscape.

Title:	Changes in populations of sea otters (Enhydra lutris) in Elkhorn Slough, California
Author:	Juliet Hoffman, California State University at Hayward
Format:	poster
Presentation:	Poster Session, 5:30 - 6:30 pm, Atrium
Abstract:	California sea otters (Enhydra lutris) are a very important animal in the Monterey Bay area. They are an indicator of a healthy marine ecosystem, and are also a valuable commodity to the local tourism industry. Once numbering as many as 300,000 in the Pacific Ocean, sea otters were hunted nearly to extinction in the 1800s for their pelts. Protected by the Endangered Species Act and other laws, sea otter populations began to steadily increase in the early 1980s. In 1995 their numbers peaked at 2,377 but began a slow but consistent decline soon after. Only 2,139 otters were counted in Spring 2002, a drop of 10 percent from 1995. Elkhorn Slough is located between Santa Cruz and Monterey, California and is part of the Monterey Bay National Marine Sanctuary. Historically otters were not permanent residents in Elkhorn Slough, but typically used the slough as a refuge during winter storm events. In 1995 there was a colonization of that area by a group of approximately 50 sea otters. This population remained as residents in the slough until 2001 when there was a marked decline in the number of otters present. This research will test and determine the cause of the decline in sea otter populations in the Elkhorn Slough area. For two years prior to this decline, an average of 50 - 60 otters were censussed in the slough. After October 2001, fewer than 20 otters were censussed in the same area with numbers typically between 8 to 10. This project will focus on testing the consistency of the apparent decline within the slough, and possible causes for this decline. Prey size used, type of prey, and tracking of tagged otters will be studied to determine any patterns that correlate abundances of otters throughout Elkhorn Slough.

Title:	Efficient and effective selection of land preserves: Why the gap between academics and practioners?
Author:	Suzanne Langridge, University of California at Santa Cruz Julie Lockwood, University of California at Santa Cruz
Format:	poster
Presentation:	Poster Session, 5:30 - 6:30 pm, Atrium
Abstract:	Reserve design algorithms have been developed to approach conservation planning in the most efficient and cost-effective manner possible. However, they are a planning tool that few managers utilize, including land trusts within the United States. U.S. land trusts have experienced phenomenal growth over the past decade and their activities (exclusive of The Nature Conservancy) have resulted in the permanent protection of over six million acres. These parcels are often of high conservation value, protecting the habitats of endangered species and the only remaining examples of unique biological communities. However, the conservation value of land trust parcels often occurs by chance, not through efficient conservation planning, and thus can incur a loss of funds and important land resources. We used data from land trust organizations to characterize the protection goals, procedures, and scale of U.S. land trust activities. We gathered information on land trust access to biological data sets and personnel training through targeted interviews. We also surveyed the scale, goals, and data requirements of 50 reserve design algorithm papers published within the four top conservation biology journals over the last 10 years. We obtained information about collaborators and motivation for conducting this research using a questionnaire sent to the primary authors of each reviewed publication. We then compared the results across groups. We found that the protection goals detailed in selection algorithms and those given by land trusts are largely compatible, as are the spatial scales at which protection is planned. However, algorithms require large amounts of information and a level of personnel training to which land trusts typically do not have ready access. Further, there is a clear gap in communication between the two groups. Our results suggest several targeted efforts are required to bridge the gap between academics and practitioners, and we identify strategies for doing so.

Title:	The influence of Carpobrotus edulis on arbuscular mycorrhizae in a coastal sage scrub community in northern California
Author:	Victoria Martinez, San Francisco State University
Format:	poster
Presentation:	Poster Session, 5:30 - 6:30 pm, Atrium
Abstract:	Carpobrotous edulis, also known as ice plant (Aizoaceae) is regarded as one of the most problematic invasive plant species and is detrimental to native plant coastal scrub communities in California. Previous research suggests that members of the Aizoaceae routinely lack AM fungi. Because C. edulis does not form a mutualistic association, C. edulis may be obstructing the colonization of mycorrhizae to native plant communities by sterilizing soil and thus inhibiting belowground processes. The objective of this study is to determine the influence of Carpobrotus edulis on the belowground activity and density of arbuscular mycorrhizal fungi (AMF) in a native plant species in the presence and the absence of ice plant. Soil samples will be analyzed for spore counts and the identification of AM fungi genera of native host plants. A bioassay will also be conducted to determine the rate of colonization between these two treatments.

Title:	Coliform monitoring in a pristine watershed
Author:	Rohana Mayer, University of California at Santa Cruz
Format:	poster
Presentation:	Poster Session, 5:30 - 6:30 pm, Atrium
Abstract:	The coliform testing at Landels-Hill Big Creek Reserve began in order to provide a baseline database of the coliform numbers that would be expected in a large pristine watershed. Nearly all of the sites monitored by other agencies have human or livestock pollution entering the flow at some point. The upper half of the watershed is part of a protected wilderness area, the lower half is part of the UC Natural Reserve System. The testing methods used have been fine-tuned over the last three years and there are about two years of reliable data. Creek, marine and spring samples are taken once a month. Readings are taken for total coliform with color differentiation of e. coli, and for fecal coliform. General trends seem to show that the coliform levels are lowest in the spring/early summer when the creeks have been scoured clean by winter flooding. There appears to be a slow build-up during summer, and a dramatic jump during the first rain after a long dry spell, with subsequent swings in the numbers corresponding to amounts of precipitation. The numbers of total colonies have risen dramatically during the most recent summer. There has been a slight change in the testing methods, but reasons for the rise are unclear.

Title:	Habitat shortage vs. life history feature incompatibility: Quantitative assessment of factors limiting numbers of a critically endangered Hawaiian solitaire
Author:	William Monahan, University of California at Berkeley Jherime L. Kellermann, US Geological Service Erik J. Tweed, US Geological Service Bethany L. Woodworth, US Geological Service
Format:	poster
Presentation:	Poster Session, 5:30 - 6:30 pm, Atrium
Abstract:	The life history phenomena characterizing a species entail consequences for population size and structure. Such features reflect past selection pressures and may not be optimal in an existing environment, especially if there has been substantial and rapid change in historical times. Endemic to the Hawaiian Islands, the Puaiohi of Kauai is a critically endangered solitaire, one of two extant members of Myadestes in the archipelago. Introduced mammalian predators and avian competitors, exotic diseases and disease vectors, and habitat degradation resulting from impacts of alien species represent recent biotic changes that potentially affect Puaiohi. Is the fragile population status of the Puaiohi a product of habitat shortage or life history features being out-of-phase with the current environment? Habitat availability was assessed in a GIS model using 2 key variables: stream proximity and elevation. Existing estimates of Puaiohi in the core population were reevaluated via transect censusing in 2001. Census results confirm the previous extrapolated total of 200-300 individuals and, coupled with the GIS model, suggest that the present population of Puaiohi is below current carrying capacity. While mean clutch size is small (2.0), the tendency towards multiple broods (up to 4), averaging 1.4 total progeny per pair per nest per 6-month breeding cycle, yields a high reproductive potential. Reproductive performance data for captive-bred, reintroduced Puaiohi suggest that present age- and sex-specific mortality patterns, perhaps shaped by exotic mammalian predators, may be limiting total population size.

Title:	Effects of the invasive tree Maesopsis eminii on the ecology of Ngezi Forest, Tanzania, and implications for reserve management
Author:	Alex Nord, Carleton College
Format:	poster
Presentation:	Poster Session, 5:30 - 6:30 pm, Atrium
Abstract:	Ngezi Forest is a small fragment of the once widespread coastal East African forest. Located in Tanzania on the island of Pemba, the reserve is now the largest remnant of the rich moist forest that once dominated the island. The protected area is currently threatened by high levels of disturbance and human encroachment. Maesopsis eminii, a tree originally introduced for timber, is spreading at an alarming rate and becoming the dominant canopy species within the reserve. An analysis of the colonization and dispersal of M. eminii and the regeneration of native flora was performed to assess the effects of the invasive tree and the risk it poses to the integrity and biodiversity of the reserve. Plots were surveyed for species composition at canopy, understory, and sapling levels, as well as M. eminii seedling populations. Results indicate that although M. eminii is capable of out-competing native species in areas of high disturbance, it competes poorly in areas of little or no disturbance where shade limits its growth and spread. M. eminii will likely continue its rapid colonization while areas of ideal growth conditions are present. However, if the forest is not further stressed, M. eminii will eventually cede its canopy dominance. Restored forest canopy suppresses M. eminii progeny growth, and recolonization by endemic species with higher shade-tolerance will promote the gradual regeneration of the native floral community. Although eradication efforts have performed well in certain conditions, these efforts will see little lasting success unless the ultimate issues of disturbance and encroachment are addressed, and the local population becomes invested in the management and sustainability of Ngezi Forest.

Title:	Phylogeography and characterization of larval dispersal within the California current by two estuarine crabs
Author:	Christine Petersen, University of California at Berkeley
Format:	poster
Presentation:	Poster Session, 5:30 - 6:30 pm, Atrium
Abstract:	Measurement of dispersal of marine larvae is a challenging task because of the difficulty of either marking or sampling larvae during migration. Modeling marine dispersal as an entirely passive function of dominant current patterns often produces poor results due to the factors of behavior, and the importance of rare events. To support a model of marine larval dispersal within the California Current system of the Northeastern Pacific, I carried out a genetic comparative analysis of dispersal between two estuarine shore crabs. Hemigrapsus oregonensis is ecologically, but not phylogenetically, similar to Rhithropanopeus harrisii, a nonindigenous species introduced around the 1930s. Contrasting the range expansion of the recently introduced species with that of the ?native? (which has existed in longer term equilibrium) provides evidence for selection between alternative hypotheses of mechanisms of dispersal along the coastline. I sequenced cytochrome oxidase I mitochondrial gene, and estimated dispersal rates, and directions using phylogeographic analysis of haplotype locations. Migration events are estimated to occur less frequently than annually. The northward range expansion of R. harrisii is evidence for the importance of the unusual northward current regime experienced during El Nino events, or the effects of the northward flowing Davidson current which occurs during Winter. Results from nested-clade analysis of haplotype locations as well as a cladistic test for asymmetry of migration direction were used to parameterize a hierarchical bayesian model of larval movement within the California current system, assuming semi-passive dispersal.

Title:	Bats as ecological indicators: A pilot study on the Sacramento River
Author:	William Rainey, University of California at Berkeley E. Pierson, University of California at Berkeley C. Corben, University of California at Berkeley S.B. Khandwala, Stillwater Sciences C.M. Champe, Stillwater Sciences B.K. Orr, Stillwater Sciences
Format:	poster
Presentation:	Poster Session, 5:30 - 6:30 pm, Atrium
Abstract:	Bats account for much of the native mammal diversity in the Sacramento Valley. All species are insectivorous and many species have been found to concentrate their foraging activities near rivers and riparian forest. Bats may be useful ecological indicators for monitoring change in river-riparian systems because they likely respond to habitat alterations occurring over broader spatial scales than less mobile animals. Although research has elucidated relationships between vegetative structure and bird communities, little is known about the species composition of bat assemblages or the habitat relationships of these species in the Central Valley of California. Current riparian and aquatic habitat restoration efforts in the Sacramento River valley, combined with new techniques for monitoring bats, offer opportunities to investigate the potential responses of bats to habitat change in this region. Some lines of inquiry we are exploring include: Do museum records accurately represent bat species richness in Sacramento River riparian forests? Is the abundance of tree-roosting species (such as the western red bat) or overall bat species diversity greater in mature riparian forests than in orchards? Do bat foraging patterns differ between riparian forest and orchard, or between mainstem river reaches and backwater areas? This pilot study is using and evaluating new passive ultrasound detection technologies for long-term monitoring of bat activity, species composition, and migratory patterns. Results from this pilot study will be used to evaluate bats and bat communities as biological indicators of river ecosystem health, as well as for guiding and evaluating restoration efforts in the region.

Papers A-G | Papers H-N | Papers O-Z | Posters

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