Vocal individuality as a potential long-term monitoring tool for Western Screech-owls, Megascops kennicottii

2006 ◽  
Vol 84 (5) ◽  
pp. 744-753 ◽  
Author(s):  
T.M. Tripp ◽  
K.A. Otter
Keyword(s):  
Discriminant Function Analysis ◽  
Cross Validation ◽  
Function Analysis ◽  
Population Monitoring ◽  
Monitoring Tool ◽  
Vocal Individuality ◽  
Discriminant Ability ◽  
Long Term Monitoring ◽  
Term Monitoring

Recent studies suggest that individually distinctive vocalizations found in many avian species can be used in population monitoring. In this study we assessed whether vocal identification of male Western Screech-owls ( Megascops kennicottii (Elliot, 1867)) was possible, and if it could be applied as a long-term monitoring tool. Recordings were collected between 2001 and 2003 from 28 territories on southern and central Vancouver Island. As a quantitative descriptor of the calls, a total of 17 variables were measured from each of 1125 calls. A discriminant function analysis resulted in 92.3% of calls being correctly classified to individual territories within one season and 87.3% of calls in a cross-validation of the model. Variables that showed the greatest discriminant ability included length of call, internote distance between first note and second note, and number of notes per call. Of the 14 territories that had owl calls recorded over 2 years, 4 appeared to be occupied by a different individual in the 2nd year, 7 had calls that were consistent between years, and 3 had calls that were ambiguously classified between years. Our results suggest that Western Screech-owl calls have enough individually recognizable characteristics to aid in the tracking of individuals both within and between years, allowing for long-term monitoring of individuals.

Population stability in the endangered Fleay’s barred frog (Mixophyes fleayi) and a program for long-term monitoring

2015 ◽  
Vol 63 (3) ◽  
pp. 214 ◽  
Author(s):  
Gemma Quick ◽  
Ross L. Goldingay ◽  
Jonathan Parkyn ◽  
David A. Newell
Keyword(s):  
National Park ◽  
New South ◽  
Monitoring Program ◽  
Population Monitoring ◽  
Population Stability ◽  
South Wales ◽  
Long Term Monitoring ◽  
Term Monitoring ◽  
Very High

In the wake of the global decline in amphibians there is a need for long-term population monitoring. Previous research suggested that the endangered Fleay’s barred frog (Mixophyes fleayi) had recovered after a severe decline. We aimed to determine whether this recovery has been sustained and to test an example of a monitoring program that could be employed at intervals of five or more years to assess long-term population stability. We conducted capture–mark–recapture five years after the last detailed census at Brindle Creek in Border Ranges National Park, New South Wales. Frogs were captured along a 200 m creek transect between September 2013 and February 2014. We used program Mark to estimate demographic parameters of adult male frogs using two modelling approaches: robust design (RD) and the POPAN formulation of the Jolly–Seber model. Abundance was estimated at 38.2 ± 0.5 (s.e.) (RD) and 46.0 ± 2.7 (POPAN). Abundance in 2008 was estimated at 53.2 ± 10.0 (POPAN) male frogs. Estimates of apparent monthly survival over our five-month-long study were very high (RD: 1.0 ± 0.0; POPAN: 1.0 ± 0.02). Recapture estimates were also high (RD: 0.40 ± 0.07 to 0.72 ± 0.05 per session; POPAN: 0.84 ± 0.05 per month). These data suggest that the Brindle Creek population has remained relatively stable over a period of ~10 years.

scholarly journals Long-term monitoring for adders: an evolving methodology

2018 ◽  
Vol 27 (Supplement) ◽  
pp. 37-43
Author(s):  
R.J. Hodges ◽  
C. Seabrook
Keyword(s):  
Population Monitoring ◽  
Chalk Grassland ◽  
Active Season ◽  
Frequent Site ◽  
Long Term Monitoring ◽  
Path Lengths ◽  
A Site ◽  
Current Monitoring ◽  
Term Monitoring

Currently, there is no recommended methodology for long-term population monitoring of European adders (Vipera berus). To open a debate on a preferred methodology, we describe an approach based on 10-years’ experience of monitoring in a chalk grassland reserve. The main elements are: 1) selection of a site with areas offering contrasting environmental conditions; 2) detection of adders along standard survey paths (transects) combined with paired artificial refuges of corrugated iron and roofing felt that are essential for detecting immature stages; 3) recognition of individual adders based on head-scale and neck patterns; 4) frequent site visits throughout the reptile active season; and 5) adoption of an Encounter Index (E.I.) that combines data from standard paths and refuges and normalises them for variations in survey effort and for shifts between years in the encounter rates along paths and at refuges. E.I. values correlate strongly with the numbers of known adders in the reserve but in some years E.I. values have been disproportionally high. Future objectives of the project are to explain variations in detectability and to estimate adder detectability associated with the current monitoring approach. Effective long-term monitoring is achievable by deploying “sufficient” refuges and, within practical limits, maximising path lengths and site visits. Future analysis of our own results will likely confirm our methodology as a “rule of thumb” for adder monitoring on, at least, chalk grassland.

Future Needs for Long-Term Monitoring Design

2003 ◽  
Author(s):  
Barbara S. Minsker ◽  
Charles Davis ◽  
David Dougherty ◽  
Gus Williams
Keyword(s):  
Monitoring Design ◽  
Future Needs ◽  
Long Term Monitoring ◽  
Term Monitoring

Investigations on potential methods for the long-term monitoring of the state of fuel elements in dry storage casks

Kerntechnik ◽  
2018 ◽  
Vol 83 (6) ◽  
pp. 513-522 ◽  
Author(s):  
U. Hampel ◽  
A. Kratzsch ◽  
R. Rachamin ◽  
M. Wagner ◽  
S. Schmidt ◽  
...  
Keyword(s):  
The State ◽  
Dry Storage ◽  
Long Term Monitoring ◽  
Potential Methods ◽  
Fuel Elements ◽  
Term Monitoring
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