The Experts below are selected from a list of 300 Experts worldwide ranked by ideXlab platform
Lisette P Waits - One of the best experts on this subject based on the ideXlab platform.
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examining the use of Fecal Pellet morphometry to differentiate age classes in sonoran pronghorn
Wildlife Biology, 2016Co-Authors: Susannah P Woodruff, Timothy R Johnson, Lisette P WaitsAbstract:Wildlife managers require knowledge of population demographics, yet for low-density, wide-ranging species procuring demographic information is challenging. While accurate abundance estimates can be costly and difficult to obtain, recruitment and survival trends can be used as an alternative indicator of a population's trajectory. Physical capture has been the traditional practice for obtaining these demographic parameters, yet capture-related stress can lead to reduced levels of fitness, impaired locomotion, or even mortality for some species. Thus, noninvasive sampling methods may provide an alternative to physical capture. Population monitoring of endangered Sonoran pronghorn Antilocapra americana sonoriensis is critical for assessing the success of recovery efforts, and monitoring annual survival and recruitment by age class would provide information on the trajectory of population growth. We measured noninvasively collected Sonoran pronghorn Fecal Pellets collected post-fawning in Arizona, USA and mat...
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rapid species identification of sonoran pronghorn from Fecal Pellet dna
Wildlife Society Bulletin, 2014Co-Authors: Susannah P Woodruff, Jennifer R Adams, Timothy R Johnson, Lisette P WaitsAbstract:The Sonoran pronghorn (Antilocapra americana sonoriensis) is a subspecies of pronghorn found exclusively in the Sonoran Desert of Arizona (USA) and Mexico. Sonoran pronghorn persist at low densities and are geographically isolated from other pronghorn populations. Numbers have declined in recent decades, but the population has rebounded from a low of fewer than 50 animals in 2003 to an estimated 159 individuals in 2012; however, little is known about population demographics beyond abundance estimates. We developed a species identification test that uses mitochondrial DNA (mtDNA) species-specific primers to distinguish between sympatric Sonoran pronghorn and mule deer (Odocoileus hemionus) using DNA extracted from Fecal Pellets. We accurately identified each species in 100% of the blood and tissue reference samples. We also evaluate the rate of DNA degradation in pronghorn Fecal samples ranging from 1 day to 124 days old and document that mtDNA species identification success rates were 100% through day 14. Success rates dropped to 95% by day 21, 50% on day 60, and 10% by day 124. This new test will be a valuable tool for documenting the presence of Sonoran pronghorn across their current range and can also be used for other pronghorn populations. © 2014 The Wildlife Society.
L. S. Mills - One of the best experts on this subject based on the ideXlab platform.
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Designing Fecal Pellet surveys for snowshoe hares
Forest Ecology and Management, 2008Co-Authors: Karen E. Hodges, L. S. MillsAbstract:Abstract Index methods can be valuable for monitoring forest-dwelling vertebrates over broad spatial or temporal scales. Fecal Pellet counts are often used as an index of density or habitat use of snowshoe hares, Lepus americanus , but previous surveys have used different plot types and sample sizes, leading to problems comparing results from different studies and questions about the inferential power of each study. In this paper, we use field data and simulations to examine how the precision, bias, and efficiency of four commonly used plot types vary with plot type, Pellet density, and sample size. Although no one plot type was consistently superior, we recommend thin rectangles (5.08 cm × 305 cm (2 in. × 10 ft), 0.155 m 2 ) or 1 m 2 circles over 0.155 m 2 circles or 10 cm × 10 m (1 m 2 ) rectangles. We recommend that researchers explicitly address the power of their survey design to detect different Pellet densities, because much larger sample sizes are needed at low Pellet densities than at high Pellet densities to obtain similar precision. Small sample sizes are also much more likely to be biased, which could lead to incorrect inferences about management of snowshoe hare populations. Both uncleared and cleared plots performed well and will have value in different research contexts.
Susannah P Woodruff - One of the best experts on this subject based on the ideXlab platform.
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examining the use of Fecal Pellet morphometry to differentiate age classes in sonoran pronghorn
Wildlife Biology, 2016Co-Authors: Susannah P Woodruff, Timothy R Johnson, Lisette P WaitsAbstract:Wildlife managers require knowledge of population demographics, yet for low-density, wide-ranging species procuring demographic information is challenging. While accurate abundance estimates can be costly and difficult to obtain, recruitment and survival trends can be used as an alternative indicator of a population's trajectory. Physical capture has been the traditional practice for obtaining these demographic parameters, yet capture-related stress can lead to reduced levels of fitness, impaired locomotion, or even mortality for some species. Thus, noninvasive sampling methods may provide an alternative to physical capture. Population monitoring of endangered Sonoran pronghorn Antilocapra americana sonoriensis is critical for assessing the success of recovery efforts, and monitoring annual survival and recruitment by age class would provide information on the trajectory of population growth. We measured noninvasively collected Sonoran pronghorn Fecal Pellets collected post-fawning in Arizona, USA and mat...
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rapid species identification of sonoran pronghorn from Fecal Pellet dna
Wildlife Society Bulletin, 2014Co-Authors: Susannah P Woodruff, Jennifer R Adams, Timothy R Johnson, Lisette P WaitsAbstract:The Sonoran pronghorn (Antilocapra americana sonoriensis) is a subspecies of pronghorn found exclusively in the Sonoran Desert of Arizona (USA) and Mexico. Sonoran pronghorn persist at low densities and are geographically isolated from other pronghorn populations. Numbers have declined in recent decades, but the population has rebounded from a low of fewer than 50 animals in 2003 to an estimated 159 individuals in 2012; however, little is known about population demographics beyond abundance estimates. We developed a species identification test that uses mitochondrial DNA (mtDNA) species-specific primers to distinguish between sympatric Sonoran pronghorn and mule deer (Odocoileus hemionus) using DNA extracted from Fecal Pellets. We accurately identified each species in 100% of the blood and tissue reference samples. We also evaluate the rate of DNA degradation in pronghorn Fecal samples ranging from 1 day to 124 days old and document that mtDNA species identification success rates were 100% through day 14. Success rates dropped to 95% by day 21, 50% on day 60, and 10% by day 124. This new test will be a valuable tool for documenting the presence of Sonoran pronghorn across their current range and can also be used for other pronghorn populations. © 2014 The Wildlife Society.
Stephanie E Wilson - One of the best experts on this subject based on the ideXlab platform.
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zooplankton Fecal Pellet flux in the abyssal northeast pacific a 15 year time series study
Limnology and Oceanography, 2013Co-Authors: Stephanie E Wilson, Henry A Ruhl, K L SmithAbstract:Sinking particulate material collected in sequencing sediment traps moored at 3500 m depth (600 m above bottom) from 1993 to 2008 at the abyssal time-series Sta. M in the northeast Pacific was analyzed via microscopy and digital imaging. Intact zooplankton Fecal Pellets were quantified and size, shape, and carbon content were measured. The most common identifiable Fecal Pellets were from larvaceans, which feed on small particles. Other abundant Fecal Pellets were likely produced by large copepods and euphausiids. The proportion of identifiable Fecal Pellet carbon to total particulate organic carbon (POC) flux varied and ranged from 3.3% to 47.7%. Fecal Pellet flux and Fecal Pellet–derived carbon flux was lowest in February, and highest in May, August, and November samples. The proportion of total POC in identifiable Fecal Pellets was negatively correlated to overall POC flux and to indicators of climate variability. The North Pacific Gyre Oscillation and Northern Oscillation Index climate indices were negatively correlated to the dominance of Fecal Pellets in POC flux, with changes in Fecal Pellet fluxes temporally lagging climate-related changes by about 3 and 5 months, respectively. Variations in zooplankton distribution and abundance affect biogeochemical cycling to abyssal depths, further demonstrating how a changing climate may affect deep-sea ecology. The dominance of zooplankton Fecal Pellets can shift proportionally, providing new insight into the processes controlling marine carbon sequestration in the deep sea.
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changes in Fecal Pellet characteristics with depth as indicators of zooplankton repackaging of particles in the mesopelagic zone of the subtropical and subarctic north pacific ocean
Deep-sea Research Part Ii-topical Studies in Oceanography, 2008Co-Authors: Stephanie E Wilson, Deborah K. Steinberg, Ken O BuesselerAbstract:We investigated how Fecal Pellet characteristics change with depth in order to quantify the extent of particle repackaging by mesopelagic zooplankton in two contrasting open-ocean systems. Material from neutrally buoyant sediment traps deployed in the summer of 2004 and 2005 at 150, 300, and 500 m was analyzed from both a mesotrophic (Japanese time-series station K2) and an oligotrophic (Hawaii Ocean Time series—HOT station ALOHA) environment in the Pacific Ocean as part of the VERtical Transport In the Global Ocean (VERTIGO) project. We quantified changes in the flux, size, shape, and color of particles recognizable as zooplankton Fecal Pellets to determine how these parameters varied with depth and location. Flux of K2 Fecal Pellet particulate organic carbon (POC) at 150 and 300 m was four to five times higher than at ALOHA, and at all depths, Fecal Pellets were two to five times larger at K2, reflective of the disparate zooplankton community structure at the two sites. At K2, the proportion of POC flux that consisted of Fecal Pellets generally decreased with depth from 20% at 150 m to 5% at 500 m, whereas at ALOHA this proportion increased with depth (and was more variable) from 14% to 35%. This difference in the Fecal fraction of POC with increasing depth is hypothesized to be due to differences in the extent of zooplankton-mediated fragmentation (coprohexy) and in zooplankton community structure between the two locations. Both regions provided indications of sinking particle repackaging and zooplankton carnivory in the mesopelagic. At ALOHA, this was reflected in a significant increase in the mean flux of larvacean Fecal Pellets from 150 to 500 m of 3–46m gCm � 2 d � 1 , respectively, and at K2 a large peak in
K L Smith - One of the best experts on this subject based on the ideXlab platform.
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zooplankton Fecal Pellet flux in the abyssal northeast pacific a 15 year time series study
Limnology and Oceanography, 2013Co-Authors: Stephanie E Wilson, Henry A Ruhl, K L SmithAbstract:Sinking particulate material collected in sequencing sediment traps moored at 3500 m depth (600 m above bottom) from 1993 to 2008 at the abyssal time-series Sta. M in the northeast Pacific was analyzed via microscopy and digital imaging. Intact zooplankton Fecal Pellets were quantified and size, shape, and carbon content were measured. The most common identifiable Fecal Pellets were from larvaceans, which feed on small particles. Other abundant Fecal Pellets were likely produced by large copepods and euphausiids. The proportion of identifiable Fecal Pellet carbon to total particulate organic carbon (POC) flux varied and ranged from 3.3% to 47.7%. Fecal Pellet flux and Fecal Pellet–derived carbon flux was lowest in February, and highest in May, August, and November samples. The proportion of total POC in identifiable Fecal Pellets was negatively correlated to overall POC flux and to indicators of climate variability. The North Pacific Gyre Oscillation and Northern Oscillation Index climate indices were negatively correlated to the dominance of Fecal Pellets in POC flux, with changes in Fecal Pellet fluxes temporally lagging climate-related changes by about 3 and 5 months, respectively. Variations in zooplankton distribution and abundance affect biogeochemical cycling to abyssal depths, further demonstrating how a changing climate may affect deep-sea ecology. The dominance of zooplankton Fecal Pellets can shift proportionally, providing new insight into the processes controlling marine carbon sequestration in the deep sea.