TY - JOUR

T1 - Counting young birds

T2 - A simple tool for the determination of avian population parameters

AU - Oldekop, Werner

AU - Oldekop, Gerd

AU - Vahldiek, Kai

AU - Klawonn, Frank

AU - Rinas, Ursula

PY - 2023/2/17

Y1 - 2023/2/17

N2 - Population parameters are usually determined from mark-recapture experiments requiring laborious field work. Here, we present a model-based approach that can be applied for the determination of avian population parameters such as average individual life expectancy, average age in the population, and generation length from age-differentiated bird counts. Moreover, the method presented can also create age-specific results from lifetime averages using a deterministic exponential function for the calculation of parameters of interest such as age-dependent mortality and age distribution in the population. The major prerequisites for application of this method are that young and adult birds are easily distinguishable in the field as well as the existence of sufficiently large data sets for error minimization. Large data sets are nowadays often available through the existence of so-called “citizen science” databases. Examples for the determination of population parameters are given for long-living migratory birds which travel as families in large groups such as the Common Crane and the Whooper Swan. Other examples include long-living partially migratory birds staying together in large flocks which do not travel as families such as the Black-headed Gull, and also short-living songbirds where at least from one sex young and adult birds are easily differentiable such as the male Black Redstart.

AB - Population parameters are usually determined from mark-recapture experiments requiring laborious field work. Here, we present a model-based approach that can be applied for the determination of avian population parameters such as average individual life expectancy, average age in the population, and generation length from age-differentiated bird counts. Moreover, the method presented can also create age-specific results from lifetime averages using a deterministic exponential function for the calculation of parameters of interest such as age-dependent mortality and age distribution in the population. The major prerequisites for application of this method are that young and adult birds are easily distinguishable in the field as well as the existence of sufficiently large data sets for error minimization. Large data sets are nowadays often available through the existence of so-called “citizen science” databases. Examples for the determination of population parameters are given for long-living migratory birds which travel as families in large groups such as the Common Crane and the Whooper Swan. Other examples include long-living partially migratory birds staying together in large flocks which do not travel as families such as the Black-headed Gull, and also short-living songbirds where at least from one sex young and adult birds are easily differentiable such as the male Black Redstart.

UR - http://www.scopus.com/inward/record.url?scp=85148293907&partnerID=8YFLogxK

U2 - 10.1371/journal.pone.0279899

DO - 10.1371/journal.pone.0279899

M3 - Article

C2 - 36800348

AN - SCOPUS:85148293907

VL - 18

JO - PLOS ONE

JF - PLOS ONE

SN - 1932-6203

IS - 2

M1 - e0279899

ER -