Geology topics

Paul C. Griffin

Publications and source records attributed to Paul C. Griffin.

12 recordsLinked to original sources

USGS2022

Post-release survival of translocated fishers: Implications for translocation success

As a vital tool for the conservation of species at risk, translocations are also opportunities to identify factors that influence translocation success. We evaluated factors associated with post-release survival of 90 radio-tracked fishers ( Pekania pennanti ) translocated from central British Columbia, Canada, to the Olympic Peninsula of Washington, USA, from 2008 to 2011. We hypothesized that the survival of translocated fishers would be affected by the same factors that influence the survival of resident, native fishers (i.e., sex, age, season, body condition), and additional factors that were associated with the translocation process (e.g., duration of captivity, release date, yr of release). Fisher survival was most strongly influenced by translocation year (i.e., release-yr cohort), season, sex, and age class of fisher; whereas duration of captivity, standardized body mass, release date, and number of intact canines did not influence survival. Survival was lowest for fishers released in cohort 2 in 2009 and during the breeding season (Mar–Jun), and was greatest for juveniles and males. When combined across release-year cohorts, year 1 survival rates were greatest for juvenile males followed by juvenile females, adult females, and adult males. Sex and age-related differences in survival of translocated fishers were counter to those commonly reported for established fisher populations, where adult females often have the highest survival rates and juveniles the lowest. Predation (40%) and vehicle strikes (20%) were the most common causes of known mortality among the 24 recovered fishers for which cause of death was determined. We speculate that females face higher risks of mortality in translocated populations because their small size makes them more vulnerable to predation and because adult females in resident populations are less likely than males and juveniles to disperse. Our findings support designing translocations that favor releasing a preponderance of female fishers in recognition of their lower survival rates and to ensure adequate breeders are established in the population, and juvenile and young adult fishers to enhance survival of both sexes. Releases conducted over multiple years will minimize the impact of stochastic annual events that may adversely affect survival in any given year. Persistence, widespread distribution, and documented reproduction of fishers within our study area for ≥6 years following the last releases indicate that survival parameters we measured contributed toward successful population establishment over the short term.

Washington↗

USGS2020

Standard operating procedures for wild horse and burro double-observer aerial surveys

The U.S. Geological Survey has been collaborating with the Bureau of Land Management to develop statistically reliable methods for wild horse and burro aerial survey data collection and analysis for more than a decade. In cooperation with Colorado State University, the U.S. Geological Survey tested several methods in herds with known abundance, resulting in two scientifically defensible aerial survey and population estimation techniques. These methods are now being applied by the Bureau of Land Management across the western United States, enabling better management of wild horses and burros. The purpose of these Standard Operating Procedures (SOPs) is to provide detailed instructions to the Bureau of Land Management wild horse and burro specialists who need to fly aerial surveys for management. This report provides multiple SOPs that are related to Equus caballus (wild horse) and Equus asinus (wild burro) double-observer aerial surveys, along with datasheets, pre-survey checklists, and a quick-guide to the methods. SOP 1 describes how to carry out wild horse and burro aerial surveys as an aviation crew member. SOP 2, SOP 3, and SOP 4 relate to data management, and are important for the wild horse and burro specialist or other lead staff who will be responsible for documenting and archiving records from the survey. SOP 5 details double-observer reporting via a data entry spreadsheet and provides reference for analyzing double observer data to obtain population estimates. SOP 6 presents general principles for preparing aerial survey flight lines. SOP 7 provides instructions for using abundance estimates from aerial surveys to project population size forward in time. The appendixes provide survey datasheets, pre-survey checklists, and a quick-guide to SOP 1.

Techniques and Methods↗

USGS2015

Estimated abundance of wild burros surveyed on Bureau of Land Management Lands in 2014

The Bureau of Land Management (BLM) requires accurate estimates of the numbers of wild horses ( Equus ferus caballus ) and burros ( Equus asinus ) living on the lands it manages. For over ten years, BLM in Arizona has used the simultaneous double-observer method of recording wild burros during aerial surveys and has reported population estimates for those surveys that come from two formulations of a Lincoln-Petersen type of analysis (Graham and Bell, 1989). In this report, I provide those same two types of burro population analysis for 2014 aerial survey data from six herd management areas (HMAs) in Arizona, California, Nevada, and Utah. I also provide burro population estimates based on a different form of simultaneous double-observer analysis, now in widespread use for wild horse surveys that takes into account the potential effects on detection probability of sighting covariates including group size, distance, vegetative cover, and other factors (Huggins, 1989, 1991). The true number of burros present in the six areas surveyed was not known, so population estimates made with these three types of analyses cannot be directly tested for accuracy in this report. I discuss theoretical reasons why the Huggins (1989, 1991) type of analysis should provide less biased estimates of population size than the Lincoln-Petersen analyses and why estimates from all forms of double-observer analyses are likely to be lower than the true number of animals present in the surveyed areas. I note reasons why I suggest using burro observations made at all available distances in analyses, not only those within 200 meters of the flight path. For all analytical methods, small sample sizes of observed groups can be problematic, but that sample size can be increased over time for Huggins (1989, 1991) analyses by pooling observations. I note ways by which burro population estimates could be tested for accuracy when there are radio-collared animals in the population or when there are simultaneous double-observer surveys before and after a burro gather and removal.

Arizona, California, Nevada, Utah↗

USGS2015

Elk monitoring in Mount Rainier and Olympic national parks: 2008-2011 synthesis report

In 2008, the USGS collaborated with the NPS, the Muckleshoot and Puyallup Indian Tribes, and WDFW to develop a protocol tor monitor changes in abundance, population composition, and spatial distribution of elk on summer ranges in MORA and OLYM and winter ranges in OLYM. We developed double-observer sightability (DO-S) models that adjusted raw counts of elk as a function of factors influencing detection probabilities from the air, e.g. vegetation, elk group size, light, elk activity, and pilot experience. We plan to develop DO-S models for both MORA and OLYM summer ranges, but due to radiotelemetry collar failures in OLYM, we do not yet have enough data to model detection probabilities in OLYM. We analyzed results of the first 4 years of elk monitoring conducted under the new protocol from 2008-2011. Objectives of this first synthetic analysis are to: • update the DO-S model for MORA aerial survey results • examine abundance, composition, and distribution of elk trends in MORA summer ranges • establish a baseline of counts, population composition, and distribution of elk in OLYM summer ranges • examine trends in counts and distribution of elk in OLYM low-elevation winter ranges during early spring • determine environmental factors influencing abundance and composition of elk in selected MORA summer ranges and unadjusted counts of elk on selected OLYM winter ranges • review progress in developing a DO-S model for OLYM elk surveys • examine aerial survey operations and provide suggestions for future surveys. There was no trend in elk numbers in the N. Rainier TCA from 2008-2011; the trend in the S. Rainier TCA was not statistically significant but increased 3.3%/year. Maximum counts increased in the N. Rainier TCA ~6%/year. Maximum counts in the S. Rainier TCA increased at a rate of 17% annually. Due to failed radiocollars, weather, and other problems, we completed surveys in 2 of 5 OLYM summer range TCAs; no trend data are available. In OLYM winter ranges, we surveyed the Hoh TCA during early spring 2008-10 and of the S. Fork Hoh and Queets in 2008 and 2010. No surveys were done for early-spring counts in 2011 and 2012 due to high snowfall and lack of funding. Legacy early-spring surveys in OLYM since 1985 allowed us to assess trends in counts in the early-spring TCAs from 1985-2010. Counts of elk in the early-spring TCAs declined: 63% in the S. Fork Hoh, 18% in the Hoh, and 22% in the Queets Valley. We continue to develop and improve the DO-S model for application to OLYM summer surveys. In the next synthesis report, we will update findings with additional data following the 2015 field season, based on 8 years of survey results; it will be a more complete analysis of elk population trends.

Washington↗

USGS2014

Elk monitoring in Lewis and Clark National Historical Park: 2008-2012 synthesis report

Maintaining elk (Cervus elaphus roosevelti) herds that frequent Lewis and Clark National Historical Park (NHP) is central to the park’s purpose of preserving the historic, cultural, scenic, and natural resources associated with the winter encampment of the Lewis and Clark expedition. Elk were critically important to the Lewis and Clark expedition in providing food and hides that sustained the expedition during the winter of 1805-06 and supplied them for their return east during 1806. Today, elk remain a key component of interpreting the Lewis and Clark story to over 200,000 park visitors each year at the Fort Clatsop visitor center. In 2008, the US Geological Survey (USGS) began collaborating with Lewis and Clark NHP and the NPS North Coast and Cascades Network to develop a protocol for monitoring long-term changes in the magnitude and spatial patterns of elk use within and adjacent to Lewis and Clark NHP (Griffin et al. 2011). Specific objectives of the monitoring program were to measure trends in (1) relative use of the Fort Clatsop unit by elk during winter; (2) the proportion of areas where elk sign is present in the Fort Clatsop unit in winter; and (3) the frequency of elk sightings from roads in and around the Fort Clatsop unit. This report synthesizes the results of the first four years of monitoring elk distribution and use in Lewis and Clark NHP from 2008-2012. We also present data from FY2012 (Appendix 1), in lieu of an annual report for that year. We used fecal pellet group surveys as the cornerstone for monitoring trends in both relative use of the Fort Clatsop Unit by elk and the proportion of areas where elk sign was present at the end of winter. We estimated pellet group density based on data collected from a network of fecal pellet plots distributed systematically throughout the unit. We developed a double observer sampling scheme that enabled us to estimate detection biases and improve the accuracy of pellet group density estimates. We computed the estimated detection probability for any pellet group observed; this probability was a function of the pellet group size and stage of decay, as well as lighting and vegetation conditions, and the number of observers (one or two) searching for pellets in that subplot. We then used these estimated detection probabilities to adjust the raw counts of the detected pellet groups to account for groups that likely went undetected under similar pellet and environmental conditions (each observed pellet group was weighted by the inverse of its estimated detection probability). We also used results from the late winter fecal pellet surveys to quantify the proportion of areas where elk pellets occurred (PAO), which was based on the presence of fecal pellet groups and estimation of detection biases (i.e., accounting for pellet groups that likely went undetected by both observers). In this synthesis, we report temporal trends in both pellet group density and PAO from 2008-2012, based on weighted linear regression analyses as well as spatial variation of pellet group densities over time. We completed late winter fecal pellet surveys at 61-66 plots annually, depending on yearly variation in access. We cleared fecal pellets at survey points in late October / early November each year and returned in late February / early March to count pellet groups left by elk over the winter. The estimated probability that a pellet group was detected by any one observer during late winter was affected most by the pellet group size and was less affected by decay class and lighting conditions. Per-observer detection probabilities ranged from as low as ~10-15% for single pellets to ~85-90% for pellet groups with 50 pellets. Average pellet group density in the Fort Clatsop unit ranged annually from 0.58 (+/- 1.43 standard error [SE]) to 0.93 (+/- 2.25 SE) pellet groups per 3-m radius subplot. Pellet group density declined over time, at approximately 8.8% per year (+/- 2.5% SE), but that slope was not statistically distinguishable from zero (2- tailed P=0.16). Following correction for detection biases, the proportion of surveyed points used by elk (i.e., PAO) ranged from 0.44 (+/- 0.07 SE) to 0.53 (+/- 0.07 SE) during the 4 winters. The estimated proportion of areas where elk pellets occurred (PAO) declined at a rate of 2.6% per year (+/- 1.2% per year SE), but that trend also was not statistically distinguishable from zero (2- tailed P=0.17). Statistical significance of a measure’s trend depends on both the magnitude (i.e., slope) of the observed trend and the number of years the trend continues in the same increasing or decreasing direction. Through simulation modeling we determined how many additional years of surveys would be required to reveal a statistically significant trend, based on the same trends in pellet group density and PAO, and associated variation, observed from 2009-2012. Assuming the same trends persist in the future, simulations indicated that there is a 70% probability that a statistically significant trend would be detected after two more years of conducting pellet group surveys. Relative use by elk during winter, as indexed by elk pellet group density, was generally greatest in the southeast region of the Fort Clatsop unit in or near the large freshwater marsh at the mouth of Colewort Creek and adjacent upland areas. Pellet group density was also higher than average in the north-central forested area, not far from a privately-owned pasture north of the park boundary. This spatial pattern in pellet group densities across the Fort Clatsop unit was consistent across all four years, although specific pellet group densities varied from year to year. Pellet group density declined significantly over time at two points in the southeast of the Fort Clatsop unit, even though pellet group density at those points remained higher than the unit average. Pellet group density increased significantly over time at one point in the north-central region, and at one point in the south-central region of the unit, indicating a slight shift in the distribution of elk use within the Fort Clatsop Unit over the four years. As an index of visitors’ opportunities to see elk in and around the Fort Clatsop Unit, we conducted replicated roadside elk surveys 3-5 times monthly during February, April, June, August, October and December 2008-2012. During each morning of survey, we searched for elk along four routes that totaled 32 km. We examined bimonthly trends in the numbers of elk groups seen, the total number of elk seen, and the observed composition ratios for those six months of the year. The average number of elk groups seen per survey ranged from 0.75 (+/- 0.32 SE) during February to a peak of 1.95 (+/- 0.36 SE) during June. Despite this seasonal variation in numbers of elk groups seen, the average total number of elk seen per morning was less variable. The average ratios of antlered elk to antlerless adult elk (i.e., bulls:cows) and calves to antlerless adult elk (i.e. calves:cows) varied seasonally, with the highest of both average ratios observed in August. We detected no significant trends in the average number of elk groups and total numbers of elk seen per survey from 2008-2012. Similarly, ratios of calves and antlered elk per antlerless elk did not differ over time. Elk groups were frequently seen from January to August in the southeast region of the Fort Clatsop unit, in the vicinity of Colewort Creek. Outside of NPS lands, we observed elk most frequently in open areas near the Astoria regional airport, in the pastures and forests immediately north of the Fort Clatsop unit and, prior to the construction of a residential development, in a pasture northwest of the Fort Clatsop unit. Elk monitoring at Lewis and Clark NHP is still in its initial years and additional monitoring will be required to verify trends that appear to be emerging. For example, the initial monitoring suggested incipient declining trends in both pellet group density and proportion of plots with pellets present, as well as, potentially, a small shift in elk distribution away from a new trail that was recently constructed in the southeast portion of the Fort Clatsop unit. Continued monitoring will aid in determining whether this local change in distribution persists (or, alternatively, resulted from short-term random variation), and whether there will be any positive or negative effect in the northern portion of the unit where a new trail has been constructed. High variability in road counts prevented our ability to find any clear trend in numbers or composition of elk observed in and near Fort Clatsop, but changes in the patterns of observations of elk from roadways suggest that residential development outside the park has reduced the available habitat for elk in some of the areas surveyed, and may have affected spatial use patterns of elk adjacent to some areas of the park. In addition to monitoring future effects of land use changes outside the park, continued monitoring may also prove useful for assessing elk responses to natural succession in forests disturbed by windthrow in December 2007 and to NPS vegetation management activities such as variable density thinning in the forest, trail development, and restoration at Otter Point tidal area and Colewort Creek Slough.

Oregon;Washington↗

USGS2014

Mount Rainier National Park

Natural Resource Condition Assessments (NRCAs) evaluate current conditions for a subset of natural resources and resource indicators in national parks. NRCAs also report on trends in resource condition (when possible), identify critical data gaps, and characterize a general level of confidence for study findings. The resources and indicators emphasized in a given project depend on the park’s resource setting, status of resource stewardship planning and science in identifying high-priority indicators, and availability of data and expertise to assess current conditions for a variety of potential study resources and indicators. Although the primary objective of NRCAs is to report on current conditions relative to logical forms of reference conditions and values, NRCAs also report on trends, when appropriate (i.e., when the underlying data and methods support such reporting), as well as influences on resource conditions. These influences may include past activities or conditions that provide a helpful context for understanding current conditions and present-day threats and stressors that are best interpreted at park, watershed, or landscape scales (though NRCAs do not report on condition status for land areas and natural resources beyond park boundaries). Intensive cause-andeffect analyses of threats and stressors, and development of detailed treatment options, are outside the scope of NRCAs. It is also important to note that NRCAs do not address resources that lack sufficient data for assessment. For Mount Rainier National Park, this includes most invertebrate species and many other animal species that are subject to significant stressors from climate change and other anthropogenic sources such as air pollutants and recreational use. In addition, we did not include an analysis of the physical hydrology associated with streams (such as riverine landforms, erosion and aggradation which is significant in MORA streams), due to a loss of staff expertise from the USGS-BRD staff conducting the work, and human disturbance landcover issues such as the effects of roads, trails, and other anthropogenic developments due to lack of funds.

Report↗

USGS2013

A hybrid double-observer sightability model for aerial surveys

Raw counts from aerial surveys make no correction for undetected animals and provide no estimate of precision with which to judge the utility of the counts. Sightability modeling and double-observer (DO) modeling are 2 commonly used approaches to account for detection bias and to estimate precision in aerial surveys. We developed a hybrid DO sightability model (model M H ) that uses the strength of each approach to overcome the weakness in the other, for aerial surveys of elk (Cervus elaphus). The hybrid approach uses detection patterns of 2 independent observer pairs in a helicopter and telemetry-based detections of collared elk groups. Candidate M H models reflected hypotheses about effects of recorded covariates and unmodeled heterogeneity on the separate front-seat observer pair and back-seat observer pair detection probabilities. Group size and concealing vegetation cover strongly influenced detection probabilities. The pilot's previous experience participating in aerial surveys influenced detection by the front pair of observers if the elk group was on the pilot's side of the helicopter flight path. In 9 surveys in Mount Rainier National Park, the raw number of elk counted was approximately 80–93% of the abundance estimated by model M H . Uncorrected ratios of bulls per 100 cows generally were low compared to estimates adjusted for detection bias, but ratios of calves per 100 cows were comparable whether based on raw survey counts or adjusted estimates. The hybrid method was an improvement over commonly used alternatives, with improved precision compared to sightability modeling and reduced bias compared to DO modeling.

Washington↗

USGS2013

Mount Rainier National Park and Olympic National Park elk monitoring program annual report 2011

Fiscal year 2011 was the first year of implementing an approved elk monitoring protocol in Mount Rainier (MORA) and Olympic (OLYM) National Parks in the North Coast and Cascades Network (NCCN) (Griffin et al. 2012). However, it was the fourth and second year of gathering data according to protocol in MORA and OLYM respectively; data gathered during the protocol development phase followed procedures that are laid out in the protocol. Elk monitoring in these large wilderness parks relies on aerial surveys from a helicopter. Summer surveys are intended to provide quantitative estimates of abundance, sex and age composition, and distribution of migratory elk in high elevation trend count areas. An unknown number of elk is not detected during surveys; however the protocol estimates the number of missed elk by applying a model that accounts for detection bias. Detection bias in elk surveys in MORA is estimated using a double-observer sightability model that was developed using survey data from 2008-2010 (Griffin et al. 2012). That model was developed using elk that were previously equipped with radio collars by cooperating tribes. At the onset of protocol development in OLYM there were no existing radio-collars on elk. Consequently the majority of the effort in OLYM in the past 4 years has been focused on capturing and radio-collaring elk and conducting sightability trials needed to develop a double-observer sightability model in OLYM. In this annual report we provide estimates of abundance and composition for MORA elk, raw counts of elk made in OLYM, and describe sightability trials conducted in OLYM. At MORA the North trend count area was surveyed twice and the South once (North Rainier herd, and South Rainier herd). We counted 373 and 267 elk during two replicate surveys of the North Rainier herd, and 535 elk in the South Rainier herd. Using the model, we estimated that 413 and 320 elk were in the North and 652 elk were in the South trend count areas during the time of the respective surveys. At OLYM, the Core and Northwest trend count areas were completely surveyed, as were portions of the Quinault. In addition, we surveyed 10 survey units specifically to get resight data. Two-hundred and forty eight elk were counted in the Core, 19 in the Northwest, and 169 in the Quinault. We conducted double-observer sightability trials associated with 14 collared elk groups for use in developing the double-observer sightability model for OLYM.

Washington↗

USGS2012

Recent population trends of mountain goats in the Olympic Mountains, Washington

Mountain goats ( Oreamnos americanus ) were introduced in Washington's Olympic Mountains during the 1920s. The population subsequently increased in numbers and expanded in range, leading to concerns by the 1970s over the potential effects of non-native mountain goats on high-elevation plant communities in Olympic National Park. The National Park Service (NPS) transplanted mountain goats from the Olympic Mountains to other ranges between 1981 and 1989 as a means to manage overabundant populations, and began monitoring population trends of mountain goats in 1983. We estimated population abundance of mountain goats during 18–25 July 2011, the sixth survey of the time series, to assess current population status and responses of the population to past management. We surveyed 39 sample units, comprising 39% of the 59,615-ha survey area. We estimated a population of 344 ± 72 (90% confidence interval [CI]) mountain goats in the survey area. Retrospective analysis of the 2004 survey, accounting for differences in survey area boundaries and methods of estimating aerial detection biases, indicated that the population increased at an average annual rate of 4.9% since the last survey. That is the first population growth observed since the cessation of population control measures in 1990. We postulate that differences in population trends observed in western, eastern, and southern sections of the survey zone reflected, in part, a variable influence of climate change across the precipitation gradient in the Olympic Mountains.

Washington↗

USGS2011

Mountain goat abundance and population trends in the Olympic Mountains, Washington, 2011

We conducted an aerial helicopter survey between July 18 and July 25, 2011, to estimate abundance and trends of introduced mountain goats (Oreamnos americanus) in the Olympic Mountains. The survey was the first since we developed a sightability correction model in 2008, which provided the means to estimate the number of mountain goats present in the surveyed areas and not seen during the aerial surveys, and to adjust for undercounting biases. Additionally, the count was the first since recent telemetry studies revealed that the previously defined survey zone, which was delineated at lower elevations by the 1,520-meter elevation contour, did not encompass all lands used by mountain goats during summer. We redefined the lower elevation boundary of survey units before conducting the 2011 surveys in an effort to more accurately estimate the entire mountain goat population. We surveyed 39 survey units, comprising 39 percent of the 59,615-hectare survey area. We estimated a mountain goat population of 344±44 (standard error, SE) in the expanded survey area. Based on this level of estimation uncertainty, the 95-percent confidence interval ranged from 258 to 430 mountain goats at the time of the survey. To permit comparisons of mountain goat populations between the 2004 and 2011 surveys, we recomputed population estimates derived from the 2004 survey using the newly developed bias correction methods, and we computed the 2004 and 2011 surveys based on comparable survey zone definitions (for example, using the boundaries of the 2004 survey). The recomputed estimates of mountain goat populations were 217±19 (SE) in 2004 and 303±41(SE) in 2011. The difference between the current 2011 population estimate (344±44[SE]) and the recomputed 2011 estimate (303±41[SE]) reflects the number of mountain goats counted in the expanded lower elevation portions of the survey zone added in 2011. We conclude that the population of mountain goats has increased in the Olympic Mountains at an average rate of 4.9±2.2(SE) percent annually since 2004. We caution that the estimated rate of population growth may be conservative if severe spring weather deterred some mountain goats from reaching the high-elevation survey areas during the 2011 surveys. If the estimated average rate of population growth were to remain constant in the future, then the population would double in approximately 14-15 years.

Washington↗

USGS2011

Elk Monitoring Protocol for Lewis and Clark National Historical Park, Version 1.0

Maintaining elk (Cervus elaphus roosevelti) herds that frequent Lewis and Clark National Historical Park (NHP) is central to the park’s purpose of preserving the historic, cultural, scenic, and natural resources. Elk were critical to sustaining the members of the Lewis and Clark expedition by providing food and clothing over the winter of 1805-1806. Today, elk viewing opportunities in the park and surrounding region generate broad appeal with the visiting public, which number over 250,000 per year at the Fort Clatsop visitor center. This protocol describes procedures for monitoring trends in the use of the Fort Clatsop area by Roosevelt elk. Specific objectives of elk monitoring in Lewis and Clark NHP are to measure the relative use and proportion of area used by elk during winter in the Fort Clatsop Unit of the park, and the rate at which elk are sighted from roads in and around the park. Relative use and the proportion of area used by elk are determined from elk fecal pellet surveys conducted every other year in the Fort Clatsop park unit. Pairs of observers visit a systematic array of permanent plots in the fall to clear them of elk fecal pellets, and return to the plots in late winter to count elk fecal pellets that have accumulated during winter. Half of the subplots are counted by two independent observers, which allows for the estimation of relative use and proportion of area occupied by elk with analyses of detection biases that account for unseen elk pellet groups. Standardized road surveys are conducted in and near the Fort Clatsop park unit three or four times monthly during alternate months. Data from road surveys are used to quantify the rate that park visitors would be expected to see elk, when driving the selected set of routes. The monitoring protocol is based on three field seasons of development and testing. The protocol narrative describes the background, rationale, sampling design, field methods, analytical methods, data management, reporting, personnel requirements, and operational requirements for elk monitoring in Lewis and Clark NHP. The sampling design reflects tradeoffs between statistical and ecological considerations, safety, and current budget considerations. The protocol provides adequate power to detect a doubling or halving of elk use in the Fort Clatsop unit and surrounding areas within 15 years. Step-by-step guidance for planning and completing the monitoring tasks are in the attached standard operating procedures (SOPs). Information on the status and trends of elk use in Lewis and Clark NHP will allow park managers to assess the effects on elk of restoration programs within the park, build community partnerships, and identify potential linkages between regional land use changes and elk use of the Park. Lewis and Clark NHP has an active ecological restoration program that aims to recreate, where possible, ecological conditions that Lewis and Clark encountered. The restoration program includes an extensive exotic plant removal program, wetland restoration, and silvicultural treatments that will hasten development of late-seral conditions in recently acquired forest lands of the Fort Clatsop park unit. In the future, monitoring results can be used to test for spatial associations between ecological restoration treatments and relative use by elk. The park also plans to feature results from elk monitoring prominently in its educational outreach activities to help interpret the historical and current ecological context of the Lewis and Clark story, and engender public support for the park mission and management activities. Although NPS does not manage non-park lands, information about trends in the distribution of elk use will be valuable in public outreach and discussions with other partnering agencies and regional private landowners.

Natural Resource Report↗

USGS2009

Survey of ungulate abundance on Santa Rosa Island, Channel Islands National Park, California, March 2009

Reliable estimates of elk (Cervus elaphus) and deer (Odocoileus hemionus) abundance on Santa Rosa Island, Channel Islands National Park, California, are required to assess the success of management actions directed at these species. We conducted a double-observer aerial survey of elk on a large portion of Santa Rosa Island on March 19, 2009. All four persons on the helicopter were treated as observers. We used two analytical approaches: (1) with three capture occasions corresponding to three possible observers, pooling the observations from the two rear-seat observers, and (2) with four capture occasions treating each observer separately. Approach 1 resulted in an estimate of 483 elk in the survey zone with a 95-percent confidence interval of 479 to 524 elk. Approach 2 resulted in an estimate of 489 elk in the survey zone with a 95-percent confidence interval of 471 to 535 elk. Approximately 5 percent of the elk groups that were estimated to have been present in the survey area were not seen by any observer. Fog prevented us from collecting double-observer observations for deer as intended on March 20. However, we did count 434 deer during the double-observer counts of elk on March 19. Both the calculated number of elk and the observed number of deer are minimal estimates of numbers of each ungulate species on Santa Rosa Island as weather conditions precluded us from surveying the entire island.

California↗