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Elise Elliott-Smith

Publications and source records attributed to Elise Elliott-Smith.

9 recordsLinked to original sources
USGS2024

Abundance of Long-billed Curlews on military lands in the Columbia Basin

Long-billed Curlews ( Numenius americanus ) are declining throughout North America, and the loss of grassland breeding habitat is one of the primary threats to the species. Intermountain West, in particular, has been identified as the most important region in North America for breeding curlews. Nevertheless, the density and abundance of Long-billed Curlews in this region is not well understood. Lands managed for military training can provide habitat for wildlife species of conservation concern, and increasingly these lands are becoming relevant to sustaining biodiversity. We conducted point count surveys of Long-billed Curlews on Department of Defense lands in the Columbia Basin near Boardman, Oregon, USA during two consecutive breeding seasons. We used multinomial-Poisson mixture models to estimate detection probability and density of curlews and to investigate environmental correlates of those metrics. Mean detection probability at a distance of 400 m was 0.45 and 0.61 in 2015 and 2016, respectively. In 2015, the clarity of skies increased detection probability, but in 2016, none of the variables we measured influenced detection probability. Mean predicted density was 3.3 (95% confidence interval: 2.4–4.7) and 1.8 (1.2–2.7) curlews/km² in 2015 and 2016, respectively. In both years, curlew density was higher in lower-elevation or topographically smoother areas. Estimated abundance of curlews in the study area was 639 (456–912) and 350 (237–520) birds in 2015 and 2016, respectively. The number of curlews appeared to fluctuate across the two years of our study, a demographic trend that may have been influenced by a wildfire in our study area in June 2015. The results of our study indicate that federal grasslands, including areas where military operations are conducted, can provide conservation benefit to breeding Long-billed Curlews.

Oregon↗
USGS2020

Black oystercatcher (Haematopus bachmani) population size, use of marine reserve complexes, and spatial distribution in Oregon

The Black Oystercatcher is a large shorebird found along the west coast of North America. Because of their small global population size, low reproductive rate, and dependence on rocky intertidal habitats, they are considered a “species of high conservation concern” and may act as an indicator of intertidal ecosystem health. In 2015, the Audubon Society of Portland initiated a 3-year shore-based population survey in Oregon building upon long-term monitoring previously conducted by the U.S. Geological Survey (USGS) and others. The objectives were to 1) Estimate the current minimum population of breeding Black Oystercatchers in Oregon and to compare that to previous estimates to better understand the population trend; 2) Document oystercatcher abundance adjacent to the Oregon’s system of Marine Reserves and Marine Protected Areas; and 3) Describe spatial distribution of breeding oystercatchers along the coast. We targeted all rocky shoreline habitats along Oregon’s coastline to perform abundance surveys each spring. A total of 75 survey routes were sampled using a standardized protocol. Trained volunteer community scientists conducted the majority of the surveys. We used N-mixture statistical models to estimate oystercatcher population size and probability of detection. Population estimates from the best fitting models were consistent, with estimates ranging from 506 oystercatchers in 2016 (95% credible interval, 463-560) to 629 (548-743) in 2015. These estimates indicated a small but stable population. Probability of detection remained consistent across years (ranging from 0.51 to 0.53). The effect of geographic region corresponded with greater bird density in the southern region of Oregon. Oystercatcher abundance adjacent to MR/MPAs accounted for between 12.4-18.3% of the total population estimate which was lower than expected (~25%). We recommend that subsequent conservation efforts directed on Black Oystercatchers in Oregon balance limiting human disturbance, particularly on the north and central coasts, with ensuring protection of core habitats on the south coast where much of the population resides.

Oregon↗
USGS2015

Data from the 2011 International Piping Plover Census

This report provides results from the 2011 International Census of Piping Plovers ( Charadrius melodus ). Distribution and abundance data for wintering and breeding Piping Plovers are summarized in tabular format. An appendix provides census data for every site surveyed in every state, province, and island. The 2011 winter census resulted in the observation of 3,973 Piping Plovers. Expanded coverage outside of the United States led to the discovery of more than 1,000 Piping Plovers wintering in the Bahamas. The breeding census detected 2,771 birds in Atlantic Canada and the Plains, Prairies, and Great Lakes regions of the United States and Canada. Combining the census count with the U.S. Atlantic “window census” provides a total minimum estimate of 5,723 breeding birds for the species.

Data Series↗
USGS2012

Large-scale monitoring of shorebird populations using count data and N-mixture models: Black Oystercatcher ( Haematopus bachmani ) surveys by land and sea

Large-scale monitoring of bird populations is often based on count data collected across spatial scales that may include multiple physiographic regions and habitat types. Monitoring at large spatial scales may require multiple survey platforms (e.g., from boats and land when monitoring coastal species) and multiple survey methods. It becomes especially important to explicitly account for detection probability when analyzing count data that have been collected using multiple survey platforms or methods. We evaluated a new analytical framework, N -mixture models, to estimate actual abundance while accounting for multiple detection biases. During May 2006, we made repeated counts of Black Oystercatchers ( Haematopus bachmani ) from boats in the Puget Sound area of Washington ( n = 55 sites) and from land along the coast of Oregon ( n = 56 sites). We used a Bayesian analysis of N-mixture models to (1) assess detection probability as a function of environmental and survey covariates and (2) estimate total Black Oystercatcher abundance during the breeding season in the two regions. Probability of detecting individuals during boat-based surveys was 0.75 (95% credible interval: 0.42–0.91) and was not influenced by tidal stage. Detection probability from surveys conducted on foot was 0.68 (0.39–0.90); the latter was not influenced by fog, wind, or number of observers but was ~35% lower during rain. The estimated population size was 321 birds (262–511) in Washington and 311 (276–382) in Oregon. N-mixture models provide a flexible framework for modeling count data and covariates in large-scale bird monitoring programs designed to understand population change.

Oregon;Washington↗
USGS2010

Long-Billed Curlew Breeding Success on Mid-Columbia River National Wildlife Refuges, South-Central Washington and North-Central Oregon, 2007-08

Long-billed curlew (Numenius americanus) reproductive success was evaluated on the Mid-Columbia River National Wildlife Refuges of south-central Washington and north-central Oregon during the 2007 and 2008 breeding seasons. Additionally, we assisted the U.S. Fish and Wildlife Service in collecting information on distribution, abundance, and brood habitat for this shorebird species of conservation concern. A total of 32 breeding pairs were located on the refuges in 2007 and 35 pairs were located in 2008. We monitored 17 nests in 2007 and 23 nests in 2008. Curlew pairs were most abundant on Hanford Reach National Monument in 2007 but more nests were located on Umatilla National Wildlife Refuge in both years, with Columbia National Wildlife Refuge supporting few pairs. Nest success was 23.6 percent in 2007 and 32.9 percent in 2008 after taking into account exposure time and combining data for all the refuges. We were unable to detect any relationship between nest success and habitat type or habitat variables measured. However, our study was the first to document use of agricultural fields on the refuge as curlew nest habitat. We collected 39 and 28 brood locations in 2007 and 2008, respectively, and many observations were likely resightings of the same brood. Broods used a similar variety of habitats as nesting curlew and no clear habitat use pattern was detected.

Open-File Report↗
USGS2009

Data from the 2006 International Piping Plover Census

This report presents the results of the 2006 International Census of Piping Plovers (Charadrius melodus). Two sets of tabular data are reported: one for distribution and abundance of wintering Piping Plovers, the other for distribution and abundance of breeding Piping Plovers. The winter census resulted in the observation of 3,884 Piping Plovers at 546 sites. The breeding census resulted in the observation of 8,092 adult piping plovers at 1,925 sites. An appendix provides census reports for each location surveyed. This report was prepared to meet an immediate need of the U.S. Fish and Wildlife Service for census data for Piping Plovers.

Data Series↗
USGS2006

Taxonomic considerations in listing subspecies under the U.S. Endangered Species Act

The U.S. Endangered Species Act (ESA) allows listing of subspecies and other groupings below the rank of species. This provides the U.S. Fish and Wildlife Service and the National Marine Fisheries Service with a means to target the most critical unit in need of conservation. Although roughly one-quarter of listed taxa are subspecies, these management agencies are hindered by uncertainties about taxonomic standards during listing or delisting activities. In a review of taxonomic publications and societies, we found few subspecies lists and none that stated standardized criteria for determining subspecific taxa. Lack of criteria is attributed to a centuries-old debate over species and subspecies concepts. Nevertheless, the critical need to resolve this debate for ESA listings led us to propose that minimal biological criteria to define disjunct subspecies (legally or taxonomically) should include the discreteness and significance criteria of distinct population segments (as defined under the ESA). Our subspecies criteria are in stark contrast to that proposed by supporters of the phylogenetic species concept and provide a clear distinction between species and subspecies. Efforts to eliminate or reduce ambiguity associated with subspecies-level classifications will assist with ESA listing decisions. Thus, we urge professional taxonomic societies to publish and periodically update peer-reviewed species and subspecies lists. This effort must be paralleled throughout the world for efficient taxonomic conservation to take place.

Conservation Biology↗