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National Quail Symposium Proceedings

Distance sampling

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The Efficacy Of Video Cameras To Account For Northern Bobwhites Flushed, But Undetected During Aerial Surveys, Andrea Montalvo, Leonard A. Brennan, Michael L. Morrison, Eric D. Grahmann, Andrew N. Tri Sep 2022

The Efficacy Of Video Cameras To Account For Northern Bobwhites Flushed, But Undetected During Aerial Surveys, Andrea Montalvo, Leonard A. Brennan, Michael L. Morrison, Eric D. Grahmann, Andrew N. Tri

National Quail Symposium Proceedings

Over the past 20 years, conventional distance sampling from a helicopter platform has been used to estimate northern bobwhite (Colinus virginianus; hereafter, bobwhite) density over large areas of rangeland vegetation. However, it has been speculated that aerial surveys can complicate the ability to meet the distance sampling assumption of detecting 100% of the target objects on the transect line due to the restricted observer view from the helicopter. We attempted to use video cameras to determine whether missed detections occurred and whether digital methods could improve the precision of bobwhite density estimates. Our objectives were to 1) determine …


Avian Abundance And Diversity On Knoxville Wildlife Area In California Following The County Fire Of 2018, Katherine S. Miller, Stacy Martinelli, Levi E. Souza Sep 2022

Avian Abundance And Diversity On Knoxville Wildlife Area In California Following The County Fire Of 2018, Katherine S. Miller, Stacy Martinelli, Levi E. Souza

National Quail Symposium Proceedings

Wildfires can have negative impacts on wildlife during and immediately after a burn event, yet these fires are also necessary for plant succession and biodiversity. Knoxville Wildlife Area (KWA) in Napa County, California, USA is a diverse environment that contains oak woodlands, chaparral, grasslands, and riparian corridors. In July 2018, the County Fire burned 36,353 ha in the Northern California Interior Coast Ranges, including 2,429 ha on KWA. California Department of Fish and Wildlife employees used this opportunity to monitor avian abundance and diversity as the burned area revegetates. From 10 June through 14 June 2019, we began a pilot …


A Monitoring Program To Evaluate The Coastal Grassland Restoration Incentive Program, Stephen J. Demaso, William G. Vermillion, Mark W. Parr Sep 2022

A Monitoring Program To Evaluate The Coastal Grassland Restoration Incentive Program, Stephen J. Demaso, William G. Vermillion, Mark W. Parr

National Quail Symposium Proceedings

The Gulf Coast Joint Venture (GCJV) is a regionally based, biologically driven, landscape-oriented volunteer partnership of private, state, and federal conservation organizations dedicated to the delivery of habitat important to priority bird species. The GCJV partnership’s Coastal Grassland Restoration Incentive Program (C-GRIP) provides financial incentives to private landowners for conducting habitat treatments that address the greatest limiting factor(s) to providing suitable grassland bird habitat on their property. The C-GRIP program is a way for the GCJV to deliver bird habitat to meet planning objectives for grassland birds, including northern bobwhite (Colinus virginianus). Our monitoring objective is to evaluate …


Distance Sampling To Assess Post-Grazing Northern Bobwhite Recovery In South Texas, Rachel A. Smith, Leonard A. Brennan, Fidel Hernández, Humberto L. Perotto-Baldivieso Nov 2017

Distance Sampling To Assess Post-Grazing Northern Bobwhite Recovery In South Texas, Rachel A. Smith, Leonard A. Brennan, Fidel Hernández, Humberto L. Perotto-Baldivieso

National Quail Symposium Proceedings

Northern bobwhite (Colinus virginianus) require habitat structure with substantial grass cover for nesting, predator avoidance, and thermal refuge. During the past 2 decades, many land managers have reduced or completely eliminated livestock across South Texas rangelands with the goal of improving bobwhite habitat. How bobwhites respond to post-grazing habitat recovery is unknown. Our objective is to investigate how bobwhites respond to the vegetative changes following removal of grazing. Our study is being conducted on a private ranch in Jim Hogg County, Texas and involves 3 different areas of post-grazing habitat recovery: a 1,246 ha area rested from grazing …


The Efficacy Of Gopro Cameras To Account For Northern Bobwhites Flushed, But Undetected During Aerial Surveys, Andrea Bruno, Leonard A. Brennan, Andrew N. Tri, Habin Su Nov 2017

The Efficacy Of Gopro Cameras To Account For Northern Bobwhites Flushed, But Undetected During Aerial Surveys, Andrea Bruno, Leonard A. Brennan, Andrew N. Tri, Habin Su

National Quail Symposium Proceedings

Estimating density and abundance is central to wildlife conservation for planning and decision-making purposes. Development of model-based techniques, such as distance sampling, allows researchers to estimate density with the inclusion of detection probabilities. However, the reliability of estimates obtained through this method are dependent upon the satisfaction of underlying assumptions, the most critical being that objects at zero distance from the observer be detected with 100% certainty. Conventional distance sampling, where line transects are traversed from an aerial platform, is a commonly used method to estimate northern bobwhite (Colinus virginianus) density over large, open areas. The restricted observer …