Dr Wojciech Kania

Ornithological Station, Museum and Institute of Zoology, Polish Academy of Sciences
Nadwiślańska 108, 80-680 Gdańsk, Poland

e-mail wkania@stornit.gda.pl (wkania@miiz.waw.pl); tel. +48 58 3080 759; fax +48 58 3080 982
po polsku

in English

Publications on: Application of nestling development traits, noted by ringers, to breeding phenology analyses and probability tables for conversion of nestling traits to age are down the page.

Estimation of the nestling age and calculation of the hatching date distribution from the nestling age and observation dates

Description of the probability method of nestling ageing and its usage in the investigations into breeding phenology can be found in papers no 49, 79 and 81 down the page.

To facilitate preparation of the probability table converting trait value to nestling age as well as to determine the hatching date distribution in a population, two computer program packages, CONTAB and HADATE were prepared, which you can download (click 77 or 78 below). You can also send me your data for processing. The data (in dbf or xls/xlsx files) should be prepared in the way described below.

General information on CONTAB and HADATE

The programs operate in FoxPro for DOS and in DOS. They are compiled and available together with supplementary DBF files as packed CONHAD.ZIP file.

Conditions which should be met by the data to be processed are listed below. This information could also be called up when executing the programs. If necessary, additional information or warnings about possible errors in the data will be printed on the screen.

Input files with one's own data can be prepared with any programs capable of producing DBF for DOS files. Structure of appropriate file EXEMP... .DBF for DOS should then be used (see below).

CONTAB - creates the table converting the value of a trait to nestling age (DBF file) from everyday measurements of the trait correlated with age.

Files CONTAB.EXE, EXEMP1.DBF and FOXDX260.ESL are required. EXEMP1.DBF together with EXEMP2a.DBF and EXEMP2b.DBF are exemplary input databases for testing the program when dealing with different data sets.

1. The input DBF file with nestling measurements has to include the fields: D1, D2, ... Dn (numerical ones, with any number of decimal places) containing measurements for consecutive (1, 2, ... n) days of life of the oldest nestling in the nest.
Each record is designed for one nest.
The fields D1, D2, ... Dn should be filled with the measurements of the nestling biggest among siblings at the time of measuring, not necessarily the same one each day.
If there is lack of measurements on a particular day, 0 or nothing should be filled in.
The input database can include additional fields, e.g. for the nest number or hatching date.
If you would like to explore abilities of the program, execute it taking as an input the exemplary files:
EXEMP1.DBF (wing length of small passerine nestlings measured within accuracy of 1 mm), EXEMP2a.DBF and EXEMP2b.DBF (dummy measurements within accuracy of 0,1).

2. The 1st day of life = last 24 hours before finding the first hatchling, assuming the nest was checked each 24 hours.

3. Measurements should be taken daily at the same time, though gaps are permitted.

4. The conversion table is based on the assumption of permanent growth of the nestling. Thus the program will stop on encountering the measurements of lower value than that of the preceding day and will ask for correction in the input database. A slow growth compared to the measurement unit, resulting in equal measurement values on consecutive days, will be accepted. Nevertheless if those values are bigger by more than one unit compared to the values from the preceding day, an error in measuring or recording is highly probable. The program will accept such data but will also inform you that they are probably incorrect.

5. Field NESTS in the output database contains numbers of nestlings (or nests, as each nestling represents a different nest), measurements of which were used to define the age distribution for each measurement unit.

6. Field AVDAY in the output database contains the mean consecutive number of the day in the life of a nestling for each value of trait. Theses mean values may be useful, e.g. when analysing the differences between age estimations taken from the conversion tables based on measurements collected in different populations.

7. The last records of the output database should be deleted if they were based on insufficient number of nestlings.

8. If the measuring of nestlings ready to escape from the nest some days before natural fledging is stopped, it can result in over-representation of slower growing nestlings in the proof, biasing the conversion table for biggest nestlings.

HADATE - creates DBF file(s) with sums of probabilities of hatching in particular nests on the consecutive days of the breeding period. Two input DBF files are needed: (1) database with a numerical trait of the age of nestlings biggest in the brood and with dates of the observation; (2) probability conversion table (converting trait to age, e.g. one prepared with the aid of CONTAB) as well as HADATE.EXE and FOX2D260.ESL.

1. The input data DBF file has to include the fields: DATE (type of expression: date) with the date of measuring, ME (numerical, with any number of decimal places) with measurement (e.g. wing length) for the nestling with the highest value of that measurement among nestmates. Each nest should be represented by 1 record. See exemplary files: EXEMP3.DBF (data from 2 populations) and EXEMP4 (with gaps in the data and with measurements bigger than those included in the exemplary conversion table EXEMP2b2.DBF.

2. The program uses the table converting trait values to age, formatted as DBF file with numerical fields ME, DZ, P1, P2, ... Pn. It can be obtained with the aid of the program CONTAB. See exemplary conversion table EXEMP11.DBF or EXEMP2B2, created with CONTAB from EXEMP1.DBF or EXEMP2a.DBF respectively.

3. Output database(s) contain(s) the fields: HATCHDATE with hatching date; PKL with probability of hatching on the day (expressed as % of all nests included in the input database or as a number of nests - as requested); DZ (optional) with numbers of days from the beginning of the year or from another date.

1.9.2005, minor formal changes 1.04.2012.

Publications on: Application of nestlings development traits, noted by ringers, to breeding phenology analyses; probability tables for conversion nestling trait to age

49a. [?] Kania W. 1982. Probability method of ageing of the passerine nestlings and its usage in breeding phenology investigations. The Ring. 110: 1-7. Extensive summary of the paper published in 1983 in Not. Orn. 24, 1-2: 46-68.

49. Kania W. 1983. Probabilistyczna metoda określania wieku piskląt ptaków wróblowatych i jej zastosowanie w badaniach fenologii rozrodu szpaka (Sturnus vulgaris). [Probability method of ageing passerine nestlings and its usage in breeding phenology investigations of starling]. Polish with English summary. Not. Orn. 24, 1-2: 46-68.

60. Kania W. 1988. Investigations of white stork Ciconia ciconia hatching phenology based on bill measurements of nestlings. The Ring 134-135: 13-19.

77. Kania W. 2001. CONTAB. Creation of the probability table for conversion nestling trait to age./Tworzenie probabilistycznej tabeli przeliczeniowej cechy pisklęcia na wiek. http://www.stornit.gda.pl/wkania

78. Kania W. 2001. HADATE. Determination of the distribution of hatching dates in a population./Określanie rozkładu dat klucia w populacji. http://www.stornit.gda.pl/wkania

79. Kania W. 2001. Określanie wieku piskląt bogatki Parus major metodą probabilistyczną na podstawie stopnia rozwoju upierzenia [Age determination of the Great Tit Parus major nestlings by means of the probability method based on feather development]. Polish with English summary. Not. Orn. 42: 117-138.

81. Kania W. 2004. Observer error in measurements of nestling wing length in small passerines. Ring 26, 2: 79-87.

89. Kania W., Chylarecki P. 2009. Ringing records as the window into the history of population changes - pitfalls and prospects in analysis of 76 years' data on Starlings Sturnus vulgaris breeding in Poland. Abstracts. 7th Conference of the European Ornitholoigists' Union, Zurich, 21 - 26 August 2009: 47.

96. Busse P., Kania W., Ożarowska A., Stępniewska K. 2012. Obrączkowanie ptaków. Fundacja Wspierania Inicjatyw Ekologicznych, Kraków. 1-66.

97. Żołnierowicz K., Tobółka M., Kania W. 2012. Zjazd założycielski Grupy Badawczej Bociana Białego (Poznań, 27–28.01.2012 r.) [The founding meeting of the White Stork Research Group (Poznań, 27–28.01.2012)]. Polish with English summary. Chrońmy Przyrodę Ojczystą, 68 (5): 323–331.

Created 2012-04-01 | updated 2016-08-21
php by tworzymy.pl