scholarly journals Standardized North American Marsh Bird Monitoring Protocol

Waterbirds ◽  
2011 ◽  
Vol 34 (3) ◽  
pp. 319-346 ◽  
Author(s):  
Courtney J. Conway
Keyword(s):  
North American ◽  
Marsh Bird ◽  
Monitoring Protocol ◽  
Bird Monitoring

scholarly journals Effectiveness of Call-Broadcast Surveys for Monitoring Marsh Birds

The Auk ◽  
2005 ◽  
Vol 122 (1) ◽  
pp. 26-35 ◽  
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

Movements of Radio-Marked California Ridgway's Rails During Monitoring Surveys: Implications for Population Monitoring

2015 ◽  
Vol 6 (1) ◽  
pp. 227-237 ◽  
Author(s):  
Thuy-Vy D. Bui ◽  
John Y. Takekawa ◽  
Cory T. Overton ◽  
Emily R. Schultz ◽  
Joshua M. Hull ◽  
...  
Keyword(s):  
San Francisco ◽  
Bird Species ◽  
Population Monitoring ◽  
Tidal Marshes ◽  
Population Abundance ◽  
Population Declines ◽  
Directional Bias ◽  
Marsh Bird ◽  
Bird Monitoring ◽  
Count Surveys

Abstract The California Ridgway's rail Rallus obsoletus obsoletus (hereafter California rail) is a secretive marsh bird endemic to tidal marshes in the San Francisco Bay (hereafter bay) of California. The California rail has undergone significant range contraction and population declines due to a variety of factors, including predation and the degradation and loss of habitat. Call-count surveys, which include call playbacks, based on the standardized North American marsh bird monitoring protocol have been conducted throughout the bay since 2005 to monitor population size and distribution of the California rail. However, call-count surveys are difficult to evaluate for efficacy or accuracy. To measure the accuracy of call-count surveys and investigate whether radio-marked California rails moved in response to call-count surveys, we compared locations of radio-marked California rails collected at frequent intervals (15 min) to California rail detections recorded during call-count surveys conducted over the same time periods. Overall, 60% of radio-marked California rails within 200 m of observers were not detected during call-count surveys. Movements of radio-marked California rails showed no directional bias (P = 0.92) irrespective of whether or not playbacks of five marsh bird species (including the California rail) were broadcast from listening stations. Our findings suggest that playbacks of rail vocalizations do not consistently influence California rail movements during surveys. However, call-count surveys may underestimate California rail presence; therefore, caution should be used when relating raw numbers of call-count detections to population abundance.

scholarly journals Detection of local-scale population declines through optimized tidal marsh bird monitoring design

2020 ◽  
Vol 23 ◽  
pp. e01128
Author(s):  
Zachary S. Ladin ◽  
Whitney A. Wiest ◽  
Maureen D. Correll ◽  
Elizabeth L. Tymkiw ◽  
Meaghan Conway ◽  
...  
Keyword(s):  
Tidal Marsh ◽  
Local Scale ◽  
Population Declines ◽  
Marsh Bird ◽  
Monitoring Design ◽  
Scale Population ◽  
Bird Monitoring

Adaptation of the Connected Speech Test: Rerecording and Passage Equivalency

2020 ◽  
Vol 29 (2) ◽  
pp. 259-264 ◽  
Author(s):  
Hasan K. Saleh ◽  
Paula Folkeard ◽  
Ewan Macpherson ◽  
Susan Scollie
Keyword(s):  
Speech Perception ◽  
North American ◽  
First Language ◽  
Intraclass Correlation ◽  
Normal Hearing ◽  
Connected Speech ◽  
Internal Reliability ◽  
Speech Test ◽  
The Mean ◽  
Unit Standard

Purpose The original Connected Speech Test (CST; Cox et al., 1987) is a well-regarded and often utilized speech perception test. The aim of this study was to develop a new version of the CST using a neutral North American accent and to assess the use of this updated CST on participants with normal hearing. Method A female English speaker was recruited to read the original CST passages, which were recorded as the new CST stimuli. A study was designed to assess the newly recorded CST passages' equivalence and conduct normalization. The study included 19 Western University students (11 females and eight males) with normal hearing and with English as a first language. Results Raw scores for the 48 tested passages were converted to rationalized arcsine units, and average passage scores more than 1 rationalized arcsine unit standard deviation from the mean were excluded. The internal reliability of the 32 remaining passages was assessed, and the two-way random effects intraclass correlation was .944. Conclusion The aim of our study was to create new CST stimuli with a more general North American accent in order to minimize accent effects on the speech perception scores. The study resulted in 32 passages of equivalent difficulty for listeners with normal hearing.

Sign in / Sign up

Export Citation Format

Share Document