Mark V. Wilson and Keli Kuykendall. Bureau of Land Management Eugene District Eugene, Oregon. Order No. 1422H090-P Prepared by.

Transcription

1 Threatened and Endangered Plants: Incorporation of Sensitive Species into the Database and Predictive Model of New Strategies for Prairie onservation, Restoration, and Management Order No. 1422H090-P Prepared by Mark V. Wilson and Keli Kuykendall Submitted to Bureau of Land Management Eugene District Eugene, Oregon Juen 6, 1997

2 Introduction The protection of threatened and endangered species continues to be a major management issue on Bureau of Land Management lands. Information for these and other species is often scattered in isolated scientific papers and unpublished reports. This is particularly true for biological information useful for conservation, restoration, and management. Moreover, it often remains unclear how to interpret existing information to design effective stewardship programs. The framework of the New Strategies for Prairie Restoration, onservation, and Management project provides a solution to these problems. The goal of this program, funded in part by The Nature onservancy, is to develop the biological understanding and technological tools necessary to manage and conserve Willamette Valley prairies. Specific activities include developing a data base of fundamental plant traits, creating a general computer model that uses this information to predict prairie responses to management actions, and testing these predictions with active adaptive management experiments. The program supported by The Nature onservancy includes only the dominant species of Willamette Valley prairies. The purpose of the present work is to expand the data base and model portions of the program to include the threatened and endangered plant species that concern the Eugene District of the Bureau of Land Management. Data base of Willamette Valley prairie species Methods Working with Kathy Pendergrass of the Bureau of Land Management, we compiled a preliminary list of sensitive plant taxa. We limited this list to plants that occur in wetland or upland prairies on property managed by the Eugene District. We then refined the list to include only those taxa that have recognized status with the US Fish and Wildlife Service, the Oregon Department of Agriculture, or The Nature onservancy. The final list contains 12 plant taxa (Table 1). Page 1

3 We searched for specific biological information on our final species list in two sources: papers in peer-reviewed journals and unpublished reports (the grey literature). To locate papers published in journals, we examined the electronic databases in the Valley Library at Oregon State University. We searched AGRIOLA, AB Abstracts, Biological and Agricultural Index, and GPO Monthly atalog. In addition, we searched the Endangered and Threatened Species data base. These informational databases provide keyword searches for papers published in journals since the mid-1970's. Unpublished reports are available primarily from their authors and recipient agencies. We contacted the Oregon Department of Agriculture, Plant onservation Biology Program, the Berry Botanic Garden, the Portland office of The Nature onservancy, and the Department of Botany and Plant Pathology of Oregon State University. These contacts provided us with copies of the reports they had on file, and identified which taxa had not received recent research attention. Finally, they provided us with the names of other botanical workers who had researched the taxa on our list. Many of the unpublished papers cited in this report were provided to us directly by their authors. Results The Willamette Valley prairie species data base is divided into general and specific information. General information covers those characteristics such as main ecological habitat, growth form, and status under the federal Endangered Species Act that do not vary. Specific information covers those plant characteristics such as growth rate or seed production that could vary from study to study. Specific information in the data base is always documented by citation to published studies or reports. The data base contains fields for more than 180 characteristics for each taxon. To date, we have used 25 published sources to determine traits for the twelve rare plant species covered in this project. omplete results are shown in Table 2 (general information) and Table 3 (specific information), with a key to field names in Table 4. Unlisted traits in Table 3 indicate that no Page 2

4 information was available for that trait. The citations supporting the specific information in Table 3 are listed in Table 5. Discussion Available research papers fell into two categories. The first was a large body of ecological research on particular habitat types, in our case grasslands and prairies. But since 11 of our 12 taxa have distributions limited to the central valleys of Oregon, they do not grow where much of the published grassland research occurs. While valuable research is currently underway in the Willamette Valley, only a small number of these projects have been written into report form, and even fewer have been published in peer-reviewed journals. Aster curtus was the only one of our 12 taxa for which ecological research has been published in peer-reviewed journals (lampitt 1987, 1993), and these studies were performed in grasslands in Washington State. The second type of information came from research into species biology. Explicit examinations of some aspect of species biology were available for only eight of our 12 taxa. Again, the available literature for these taxa was limited primarily to agency reports (grey literature). Research into species biology was available for six of the seven taxa with federal and state status. Both taxa without federal or state status that received biological examination did so as part of larger graduate studies (Broich 1983, Henderson 1976). Several trends can be seen in what available information was available. Reproduction details are the first research topic to receive attention. We found information about some aspect of reproduction, such as seed or inflorescence attributes, for all 12 species. Much of this work came from intensive species biology work, such as that done on Erigeron decumbens var. decumbens (lark et al.1993, 1995a, 1995b and 1997) and Montia howellii (Kagan 1989, Kaye 1992b). In other cases, our taxa were included in larger studies, such as on germination (Guerrant and Raven 1995) or systematics (Henderson 1976, Broich 1983). Page 3

5 Another trend in the available information is the lack of available, published information on individual plant responses to competition, mowing, and fire. Only one researcher reported the results of competition experiments (lampitt 1987). Although response of prairie vegetation to fire has been an active research topic in the Willamette Valley, most measurements have been at the population level, rather than at the individual level. Since population trends can arise from a variety of mechanisms (for example, changes in establishment, growth, or mortality), they say little about a plant s fundamental traits. Research is underway, conducted in part under the New Strategies program, that will fill some of these important information gaps. Finally, the amount of total research was disproportionately distributed to only a few taxa. Aster curtus, Erigeron decumbens var. decumbens, Horkelia congesta ssp. congesta, Lomatium bradshawii, Lupinus sulphureus ssp. kincaidii, and Montia howellii have received research attention from several workers over several years. icendia quadrangularis, Lathyrus holochlorus, Meconella oregana, Sidalcea campestris, and Sisyrinchium hitchcockii have received very little research work. Of the latter, only Meconella oregana has federal and state status. Research on Sidalcea cusickii recently has begun at Oregon State University. A species federal or state status triggers research activity. Sisyrhincium hitchcockii has problems unique to our group of 12 taxa. This species was only recognized in 1976 (Henderson 1976). While Henderson's treatment is considered taxonomically valid (K. hambers pers. comm.) the entire genus of Sisyrinchium in Oregon is difficult to evaluate from herbarium material. This means that the only reliable way to identify members of this genus is through live material in the field. Therefore, even basic information regarding population sizes and locations are not available. Prairie model Background Page 4

6 The general objectives and modeling approach for the prairie model were developed at the time of the New Strategies proposal. Kathy Pendergrass of the BLM Eugene District participated in this phase of model development. The original version of the model described plants in terms of their fundamental plant traits. Although this works well for predicting general vegetation changes, it does not allow tracking of individual species. The changes we have made under this contract allow predictions of the effects of prairie dynamics and management manipulations on specified rare plants. Model description The core of the prairie model is a series of routines that parallel plant life history events (Figure 1). These routines calculate new plant ages, soil seed bank dynamics, seedling establishment, effects of crowding, growth and death of individuals, effects of management manipulations, and seed production by mature plants. Key model parameters reflect the life history traits represented in the core routines (Table 6). The prairie model now tracks individual plants of each species in separate plots within a community. Plant size, age, and life history stage are currently updated annually. The model is programmed in the APL language, which allows for compact and flexible code (Table 7) and rapid modification. The modeling approach taken in this project is to include enough biological detail to produce realistic predictions, yet to remain general enough to be robust in field applications. We illustrate this modeling approach by describing two aspects of the prairie model, dispersal and competition. The model considers three types of dispersal (recorded in parameter pdispersal). Widespread dispersal means that seeds are always available within a community from long-range dispersal, at a rate determined by maximum seed rain (pdispmax). Narrow dispersal means that if a species is represented by reproductively mature plants anywhere within the community, its seeds Page 5

7 are available in every plot, at a rate determined by the maximum seed rain and by actual seed production. Local dispersal means that seeds are available within a plot only from seed production by individuals within that plot. urrent ecological theory separates competition into the depletion of resources by neighbors (competitive effects) and the effect this depletion has on target individuals (competitive responses). This approach to competition is a three-step process in the model. The first step is depletion of generalized aboveground (light) and belowground (water and nutrients) resources. Resource depletion by a species is the product of depletion ability per plant (peabove and pebelow) and the number of plants present. The calculations are done separately for different sizes of plants of each species. The second step is determining the degree of crowding. Belowground crowding is the sum of resource depletion for all plants within a plot. Aboveground crowding is the sum of resource depletion for all plants within a plot of similar size or larger than the target plant. The third step is letting crowding reduce the target plant s chance of surviving, growing, and producing seed. The degree of reduction depends on the species inherent ability to tolerate crowding (parameter ptable6). Future work The next step in model development is to determine biologically realistic values for the key parameters. The Willamette Valley prairie species data base provides the information needed to make these determinations. We will then compare model predictions against long-term field data from our Willamette Valley field sites. Discrepancies between model predictions and observations will point out where the model or parameters need to be refined. Once validated, the model will provide BLM land stewards with an important tool for designing effective plant conservation programs. We look forward to working with BLM personnel in using the prairie model to inform management decisions. Page 6

8 Table 1. Species added to the Willamette Valley prairie species data base and the prairie model. Each is threatened, endangered, or otherwise rare and is found within the BLM Eugene District. : candidate; LE: listed as endangered; LT: listed as threatened; Lx: listed by The Nature onservancy with importance x; S: species of concern. Species Federal status State status TN status Aster curtus S LT L1 icendia quadrangularis (=Microcala quadrangularis) Erigeron decumbens var. decumbens none none L2 LE L1 Horkelia congesta ssp. congesta S L1 Lathyrus holochlorus none none L4 Lomatium bradshawii LE LE L1 Lupinus sulphureus ssp. kincaidii S LT L1 Meconella oregana S L1 Montia howellii S L1 Sidalcea campestris none none L4 Sidalcea cusickii none none L4 Sisyrinchium hitchcockii none none L1

9 Table 4. Key to the fields for the specific information within the Willamette Valley prairie species database (see Table 3). Q = quantitative variable; = categorical variable; T = free text variable; sd: seed; sdl: seedling; juv: juvenile; mat: mature. Short name on form Full field name Type Normal domain 1st flowering-age Age at first flowering Q year 1st flowering-date Date of first flowering Q Julian date 1st germ (month) Month of first germination Q month After-rip req After-ripening requirement absolute / partial / none arbo translocation (month) Month of main carbohydrate translocation Q month omp gen General competitive ability omp juv-juv Performance in competition: juvjuv omp juv-juv (Hi fertility) Performance in competition: juvjuv (high soil fertility) omp juv-juv (Lo fertility) Performance in competition: juvjuv (low soil fertility) omp juv-mat Performance in competition: juvmat omp mat-mat Performance in competition: matmat omp mat-mat (Hi fertility) Performance in competition: matmat (high soil fertility) omp mat-mat (Lo fertility) Performance in competition: matmat (low soil fertility) omp sdl-mat Performance in competition: sdlmat omp sdl-sdl Performance in competition: sdlsdl omp sdl-sdl (Hi fertility) Performance in competition: sdlsdl (high soil fertility) omp sdl-sdl (Lo fertility) Performance in competition: sdlsdl (low soil fertility)

10 Disperal dist Dispersal distance (median) Q cm Dispersal regularity Dispersal regularity regular / mast / irregular Dispersers Observed dispersers T text Disturb affin Disturbance affinity high / medium / low Emerg % 1st yr Emergence in the first year Q % Emerg % 2nd yr Emergence in the second year after sowing Q % Emerg date (month) Emergence month Q month Emergence (%) Field emergence rate Q % Endogenous sd dorm? Does the seed possess endogenous dormancy? yes / no Establishment Field establishment rate Q % Fire break dormancy? Fire break dormancy? yes / no Fire-repro Reproductive response of individuals to fire First disp-date Date of first dispersal Q Julian date Flrs/inflor Flowers per inflorescence Q Flrs/stem Flowers per stem Q Fls/plant Flowers per plant Q Fruits/plant Fruits per plant Q Germ % after 1 yr in field Germination after 1 year in soil Q % Germ percentage Germination rate (%) Q % GR-early mow (mat) Growth response of matures to non-fall mowing GR-early mow (juv) Growth response of juveniles to non-fall mowing GR-early mow (sdl) Growth response of seedlings to non-fall mowing GR-fire after 1 yr (mat) Growth response of survivors 1 year after fire: matures GR-fire after 2 yrs (mat) Growth response of survivors 2 years after fire: matures

11 GR-fire cool (juv) cool fire: juveniles GR-fire cool (mat) cool fire: matures GR-fire cool (sdl) cool fire: seedlings GR-fire hot (juv) hot fire: juveniles GR-fire hot (mat) hot fire: matures GR-fire hot (sdl) hot fire: seedlings GR-gen fire (juv) General growth response of survivors to fire: juveniles GR-gen fire (mat) General growth response of survivors to fire: matures GR-gen fire (sdl) General growth response of survivors to fire: seedlings GR-gen mow (juv) Growth response of juveniles to unspecified mowing GR-gen mow (mat) Growth response of matures to unspecified mowing GR-gen mow (sdl) Growth response of seedlings to unspecified mowing GR-late fire cool (mat) fire (fall, cool): matures GR-late fire cool (juv) fire (fall, cool): juveniles GR-late fire cool (sdl) fire (fall, cool): seedlings GR-late fire hot (mat) fire (fall, hot): matures Q GR-late fire hot (sdl) fire (fall, hot): seedlings Q GR-late fire hot (juv) fire (fall, hot): juveniles Q GR-late mow (juv) Growth response of juveniles to fall mowing

12 GR-late mow (mat) Growth response of matures to fall mowing GR-late mow (sdl) Growth response of seedlings to fall mowing Hgt-juv Height of juveniles Q cm Hgt-sdl Height of seedlings Q cm Last disp-date Date of last dispersal Q Julian date Last fl-date Date of last flowering Q Julian date Light increases germ? Does light increase germination? yes / no Light req for germ? Is light a requirement for germination? yes / no Litter production Litter production high / medium / low Litter-emerg Ability to emerge through litter high / medium / low Longevity foliage Foliage longevity fall-sum / spr-sum / semi-everg /evergreen Longevity leaf Leaf longevity Q day Longevity plant Plant longevity T range of years Myc dependence Mycorrhizal dependency obligate / facultative / fac or obl / none Myc-type Type of mycorrhiza arbuscular / ecto Nutr affin Soil nutrient affinity high / medium / low Ovules per fruit Ovules per fruit Q Peak disp-date Date of peak dispersal (1) Q Julian date Peak disp-month Date of peak dispersal (2) Q month Peak disp-season Date of peak dispersal (3) spring / summer / fall / winter Peak fl-date Date of peak flowering (1) Q Julian date Peak fl-month Date of peak flowering (2) Q month Peak fl-season Date of peak flowering (3) spring / summer / fall / winter Peak germ-date Time of peak germination (1) Q Julian date Peak germ-month Time of peak germination (2) Q month Peak germ-season Time of peak germination (3) spring / summer / fall / winter Plant mass (avg.) Average plant mass Q g

13 RGR juveniles General RGR of juveniles slow / medium / fast RGR mature General RGR of matures slow / medium / fast RGR seedling General RGR of seedlings slow / medium / fast RGR-juv (opt) RGR of juveniles (optimal) Q (entered) RGR-juv (sub) RGR of juveniles (suboptimal) Q (entered) RGR-mat (opt) RGR of matures (optimal) Q (entered) RGR-mat (sub) RGR of matures (suboptimal) Q (entered) RGR-sdl (opt) RGR of seedlings (optimal) Q (entered) RGR-sdl (sub) RGR of seedlings (suboptimal) Q (entered) Scar req Scarification requirement yes / no Sdlg survivorship (%) Seedling survivorship (% per year) Q % per year Sec germ-date Time of 2E germination (1) Q Julian date Sec germ-month Time of 2E germination (2) Q month Sec germ-season Time of 2E germination (3) spring / summer / fall / winter Seed bank density (approx) Approximate soil seed bank density low / medium / high / none Seed bank size Persistent seed bank density Q number / m 2 Seed length Average seed length Q mm Seed longevity Seed longevity Q year Seed mass Average seed mass Q mg Seed viability Seed viability Q % Seeds filled % Seeds filled Q % Seeds/fl Seed production (1) Q number per flower Seeds/inflor Seeds per inflorescence Q Seeds/plant (weight) Seed weight per plant Q g Seeds/plant Seed production (2) Q number per plant Seeds survive burning Do seeds survive burning? yes / no Shade tol-sdl Shade tolerance of seedlings full shade / partial shade / intolerant

14 Shade tolerant general General shade tolerance yes / no Spread-juv Spread of juveniles H>W, H=W, H<W Spread-mat Spread of matures H>W, H=W, H<W Stems/plant Stems per plant Q Strat req Stratification requirement yes / no Surv drought (juv) Survival of drought: juveniles Q % Surv drought (mat) Survival of drought: matures Q % Surv drought (sdl) Survival of drought: seedlings Q % Surv-fire cool (juv) Survival of cool fire: juveniles Q % Surv-fire cool (mat) Survival of cool fire: matures Q % Surv-fire cool (sd) Survival of cool fire: seeds Q % Surv-fire cool (sdl) Survival of cool fire: seedlings Q % Surv-fire hot (juv) Survival of hot fire: juveniles Q % Surv-fire hot (mat) Survival of hot fire: matures Q % Surv-fire hot (sd) Survival of hot fire: seeds Q % Surv-fire hot (sdl) Survival of hot fire: seedlings Q % Vectors Observed pollination vectors T text Vege prop Vegetative propagation high / medium / low

15 Table 6. Parameters, global variables, and initial conditions of the prairie model. APL term Dimensions (see initial conditions) Explanation Domain Parameters (fundamental plant traits) peabove icnspp, 3 Relative impact on aboveground resources (determined for each life stage) pebelow icnspp, 3 Relative impact on belowground resources (determined for each life stage) prowdtype icnspp Group a species belongs to in terms of response to crowding % % Loses / Persists / Aggressive pdispersal icnspp Dispersal type Wide / Narrow / Local pdispmax icnspp Maximum seed rain for widely dispersed species Number per m 2 pgerm icnspp Germination and establishment rate % per year pjtom icnspp, 2 Age and height needed to go from juvenile to mature Year, stratum number pmaxage icnspp Maximum age Year pmaxhgt icnspp Maximum height Stratum number ppot icnspp Potential for seed production under good conditions Number per individual pseedlr icnspp Mortality rate for seeds in soil (temp) % per year pspr icnspp, 3 Seed production response to crowding ptable6 3, 3, 3 Proportion of life stage surviving, growing % % per year

16 Global variables gvages icnspp (nested) Age of each individual Year gvi icnstrata rowding intensity, by stratum Density level (1-sparse, 2-medium, 3-dense) gvhgts icnspp (nested) Height of each individual Stratum number gvseedprod icnspp Seed production Number per plot gvseeds icnspp Size of soil seed bank Number per plot gvstages icnspp (nested) Life history stage of each individual Stage number (1- seedling, 2-juvenile, 3- mature) Initial conditions icutoff 3 Transition values between sparse and medium and dense crowding Values of gvi icnplots 1 Number of plots Integer icnspp 1 Number of species Integer icnstrata 1 Number of strata Integer icplotsize 1 Plot size m 2

17 Figure 1. Structure of the prairie model. The core routines calculate new plant ages (Age), soil seed bank dynamics (SeedIO), seedling establishment (Establish), effects of crowding (rowding), growth and death of individuals (Demog), effects of management manipulations (Manip), and seed production by mature plants (SeedProd).