Combining historical accounts with contemporary bird survey data identifies changes in an avian community over a period of anthropogenic change

In 2007, a fire burned over 100000ha along the Anaktuvuk River in Alaska, causing widespread ecological disturbance. Despite efforts to understand ecosystem recovery, little is known about higher trophic levels. Here, we present qualitative findings from a preliminary bird survey of the burn scar region, conducted in 2014, at three sites representing varying severity of burn damage. We found that abundance and species richness both appear higher at a site that experienced a moderate degree of burn damage than unburned control and severely burned sites. These findings suggest that the impacts of fires on bird communities may be minimal within 7 years post fire. Furthermore, our findings highlight the need for more rigorous efforts to understand the dynamics of tundra bird community fire recovery in a rapidly changing world.

Download Full-text

Use of North American Breeding Bird Survey data in avian conservation assessments

The Condor ◽

10.1650/condor-17-57.1 ◽

2017 ◽

Vol 119 (3) ◽

pp. 594-606 ◽

Cited By ~ 16

Author(s):

Kenneth V. Rosenberg ◽

Peter J. Blancher ◽

Jessica C. Stanton ◽

Arvind O. Panjabi

Keyword(s):

Survey Data ◽

North American ◽

Breeding Bird Survey ◽

Avian Conservation ◽

Breeding Bird ◽

Bird Survey ◽

Conservation Assessments

Download Full-text

Using the North American Breeding Bird Survey to assess broad-scale response of the continent's most imperiled avian community, grassland birds, to weather variability

The Condor ◽

10.1650/condor-15-180.1 ◽

2016 ◽

Vol 118 (3) ◽

pp. 502-512 ◽

Cited By ~ 19

Author(s):

Jessica M. Gorzo ◽

Anna M. Pidgeon ◽

Wayne E. Thogmartin ◽

Andrew J. Allstadt ◽

Volker C. Radeloff ◽

...

Keyword(s):

North American ◽

Grassland Birds ◽

Breeding Bird Survey ◽

Weather Variability ◽

Avian Community ◽

Breeding Bird ◽

The North ◽

Scale Response ◽

Bird Survey ◽

Broad Scale

Download Full-text

Antarctic Site Inventory breeding bird survey data, 1994–2013

Ecology ◽

10.1890/13-1108.1 ◽

2013 ◽

Vol 94 (11) ◽

pp. 2653-2653 ◽

Cited By ~ 15

Author(s):

Heather J. Lynch ◽

Ron Naveen ◽

Paula Casanovas

Keyword(s):

Survey Data ◽

Breeding Bird Survey ◽

Breeding Bird ◽

Bird Survey

Download Full-text

Effectiveness of Call-Broadcast Surveys for Monitoring Marsh Birds

The Auk ◽

10.1093/auk/122.1.26 ◽

2005 ◽

Vol 122 (1) ◽

pp. 26-35 ◽

Cited By ~ 10

Author(s):

Courtney J. Conway ◽

James P. Gibbs

Keyword(s):

Survey Data ◽

Detection Probability ◽

Monitoring Program ◽

Marsh Bird ◽

Point Count ◽

Marsh Birds ◽

Monitoring Protocol ◽

Bird Survey ◽

Bird Monitoring ◽

Monitoring Effort

Abstract Many species of marsh birds (e.g. rails and bitterns) are believed to be declining in North America, yet we lack an effective monitoring program to estimate their population trends. Broadcast of prerecorded calls to elicit vocalizations is a commonly used method in surveys of marsh birds, but whether gains in detection and index precision outweigh the drawbacks of call-broadcast is unclear. To evaluate the effectiveness of call-broadcast surveys, we pooled marsh-bird survey data from 8,047 point-count surveys contributed by 11 cooperators and compared numbers of birds detected and variation in numbers detected between call-broadcast and passive surveys. For most rails (particularly Virginia Rails [Rallus limicola]), call-broadcast surveys were effective at increasing the detection probability (e.g. average number of Virginia Rails detected per occupied point was 1.25 for call-broadcast surveys and 0.17 for passive surveys). The proportion of points at which no birds were detected was high for all species (range 74–99%) and was slightly lower on call-broadcast surveys as compared with passive surveys. Coefficient of variation (CV) among replicate surveys was higher for passive surveys, particularly for rails (average CV in number of birds detected per point was 209% for passive surveys and 189% for call-broadcast surveys). On the basis of those results, we recommend a marsh-bird monitoring protocol that includes an initial passive period followed by a period of call-broadcast to provide survey data that incorporate the benefits while avoiding the drawbacks of call-broadcast. We also recommend separating both the passive and the call-broadcast periods into 1-min subsegments that will allow estimates of components of detection probability within the monitoring effort. Efectividad de Censos que Reproducen Vocalizaciones Pregrabadas para Monitorear Aves de Pantano

Download Full-text

Combination of targeted monitoring and Breeding Bird Survey data improves population trend estimation and species distribution modeling for the Common Nighthawk

The Condor ◽

10.1093/ornithapp/duab005 ◽

2021 ◽

Author(s):

Elly C Knight ◽

Adam C Smith ◽

R Mark Brigham ◽

Erin M Bayne

Keyword(s):

Survey Data ◽

Population Decline ◽

Predictive Performance ◽

Population Trend ◽

Breeding Bird Survey ◽

Breeding Bird ◽

Monitoring Programs ◽

Bird Survey ◽

Starting Point ◽

The Common

Abstract Standardized monitoring is critical for conservation because reliable survey data are used to inform the necessity, type, and effectiveness of conservation actions. Many of the avian monitoring data used for conservation are collected by “comprehensive” programs that survey for all species observed; however, there are some species that have low availability for detection during comprehensive surveys and are instead monitored with targeted programs. Unfortunately, those targeted programs are rarely evaluated relative to existing programs and management objectives to inform allocation of effort. We assessed the statistical performance of the comprehensive North American Breeding Bird Survey (BBS), the targeted Canadian Nightjar Survey (CNS), and the two programs combined for the Common Nighthawk (Chordeiles minor). First, we used parameters from the existing datasets to simulate population declines and determined the probability of detecting those declines. Analyses that combined both datasets resulted in higher probability of detecting a 30% population decline (BBS: 38%, CNS: 64%, combined: 69%). Next, we built probability of occurrence models and assessed the predictive performance of those models. Combined analyses had similar predictive performance to the CNS and moderated poor performance of the BBS in the north (mean Cohen’s kappa; BBS: 0.40, CNS: 0.46, combined: 0.50). Our results suggest that data from targeted monitoring is important for evaluation of Common Nighthawk population trend and habitat relationships but is best combined with BBS data. Comprehensive and targeted monitoring programs may be better when considered together, and exploration of data combination should become the rule, not the exception. We suggest that the framework we present can be used as a starting point for evaluating targeted monitoring programs relative to defined objectives and existing programs, with the potential to explore hypothetical management scenarios.

Download Full-text

Estimating Population Trends With a Linear Model

The Condor ◽

10.1093/condor/105.2.367 ◽

2003 ◽

Vol 105 (2) ◽

pp. 367-372

Author(s):

Jonathan Bart ◽

Brian Collins ◽

R. I G. Morrison

Keyword(s):

Linear Model ◽

Survey Data ◽

Point Estimate ◽

Breeding Bird Survey ◽

Survey Period ◽

Breeding Bird ◽

Data Set ◽

Bird Survey ◽

Modelo Lineal ◽

T Distribution

Abstract We describe a simple and robust method for estimating trends in population size. The method may be used with Breeding Bird Survey data, aerial surveys, point counts, or any other program of repeated surveys at permanent locations. Surveys need not be made at each location during each survey period. The method differs from most existing methods in being design based, rather than model based. The only assumptions are that the nominal sampling plan is followed and that sample size is large enough for use of the t-distribution. Simulations based on two bird data sets from natural populations showed that the point estimate produced by the linear model was essentially unbiased even when counts varied substantially and 25% of the complete data set was missing. The estimating-equation approach, often used to analyze Breeding Bird Survey data, performed similarly on one data set but had substantial bias on the second data set, in which counts were highly variable. The advantages of the linear model are its simplicity, flexibility, and that it is self-weighting. A user-friendly computer program to carry out the calculations is available from the senior author. Estimación de Tendencias Poblacionales con un Modelo Lineal Resumen. Decribimos un método simple y robusto para estimar tendencias en tamaños poblacionales. El método puede utilizarse con datos del Censo de Aves Reproductivas, de censos áereos, de conteos por punto o de cualquier otro programa de censos repetidos en localidades permanentes. Los censos no necesitan hacerse en cada localidad durante cada período de censado. El método difiere de la mayoría de los que existen en que está basado en un diseño y no en un modelo. Las únicas suposiciones son que se sigue el plan de muestreo nominal y que el tamaño de muestreo es suficientemente grande para el uso de la distribución t. Simulaciones basadas en dos grupos de datos de poblaciones naturales de aves mostraron que el estimativo puntual producido por el modelo fue esencialmente no sesgado, incluso cuando los conteos variaban sustancialmente y faltaba el 25% del juego completo de datos. El enfoque de estimación de ecuaciones, usado con frecuencia para analizar datos del Censo de Aves Reproductivas, se comportó de manera similar en un grupo de datos, pero presentó un marcado sesgo en el otro, en el que los conteos eran altamente variables. Las ventajas del modelo lineal son su simplicidad, flexibilidad y que se auto-evalua. Un programa de computador de fácil uso para realizar los cálculos está disponible a través del primer autor.

Download Full-text