Atlas pospolitych ptaków lęgowych Polski

Atlas of Common Breeding Birds in Poland:
Distribution, Habitat Preferences and Population Trends
Scope of the Atlas
This book is aimed to fulfil the gap in our knowledge on the
distribution, numbers, habitat use and population trends
of common breeding birds in Poland. We present here the
detailed information on predicted spatial distributions
for 80 bird species. For all of them, the habitat suitability
maps are provided, prepared in the resolution of 1 × 1 km.
The species distribution maps resulted from generalisation
of rules and patterns revealed while modelling their
habitat preferences, based on information gathered from
more than 700 sampling plots spread across the country.
For each species, beside maps showing spatial distribution
of habitat suitability, we also include estimates of the total
population, occupancy (in the 1 km grain), information on
habitat preferences and population trends over the years
2000–2010. Additionally, based on the information on population
trends and using IUCN regional criteria, we made
assessments of the threat status for all species considered
in the book. Finally, we showed regions within the country,
which support largest populations of these common, although
already threatened bird species. These hot-spots of
declining common birds define areas where conservation
actions should be targeted in the nearest future.
Bird data
Common Breeding Bird Survey
The basic data on bird numbers used in this book came
from the Polish Common Breeding Bird Survey (Monitoring
Pospolitych Ptaków Lęgowych, MPPL). MPPL is a multispecies
bird survey aimed to provide annual population
indices for the most widespread breeding bird species in
Poland. The project is methodologically based on the British
Breeding Bird Survey (BBS), carried out in the UK by the
British Trust for Ornithology. The MPPL programme started
in 2000 as a result of cooperation between the Polish Society
of Protection of Birds (BirdLife Poland, OTOP), Polish
Academy of Sciences (PAN) and the Royal Society for the
Protection of Birds (RSPB). In the years 2000-2006 it was
financed by RSPB, UN (GEF/ Small Grants Programme) and
EU (The Cooperation Fund). Since 2007 MPPL is run by
Chief Inspectorate of Environmental Protection (Główny
Inspektorat Ochrony Środowiska, GIOŚ), thanks to financial
support of National Fund for Environmental Protection
and Water Management (NFOŚiGW). OTOP is operating
the programme.
Main features of the MPPL design and fieldwork protocol
are listed below.
–– Survey plots are 1 × 1 km squares selected at random
from within the country. Stratified random sampling
––
––
––
––
was used to select plots, with 15 geographical regions
of Poland used to define strata.
Within each plot, birds are counted while walking two
parallel 1 km-long transects situated c. 500 m apart.
Birds were surveyed twice a season, with early visit
paid between 10 April and 15 May and late visit paid
between 16 May and 30 June. The two visits should be
separated by at least four weeks. Each visit started between
sunrise and 9:00 a.m. and lasted some 90 minutes.
On each visit, observers recorded all birds seen or
heard, using three distance bands from the transect
line: 0–25 m, 25–100 m, and over 100 m (no upper
bound); birds in flight are registered separately.
The same survey plots are visited in successive years
and birds are counted from the same transects.
Data used
Data used in this Atlas were collected in the years 2000–
2010 by 578 volunteer observers surveying birds on 776
sampling plots (Fig 2.2). Totally, they made 8841 visits to
the field plots and recorded more than 600 thousands of
single observations. The full list of observer’s names is provided
in Appendix 1.
Data analysis
Densities and occupancy
Density estimates were calculated for each 1 × 1 km survey
plot using the software DISTANCE 6.0 release 2 (Thomas
et al. 2010). A half-normal model with no adjustments was
selected (Fig. 2.3). Data outside the range of 100 m contain
observations of unknown distance (the furthest distance
band, extending beyond 100 m no upper distance bound
for registered individuals) and were excluded from density
estimation. Density estimates were stratified by year and
weighted according to the total effort (measured by total
length of all transects sampled) in each stratum. Mean densities
for each 1-km square were calculated across all years
the plot was sampled. National population size for each
species was estimated by multiplying the mean density
and the total country area (312,888 km 2 ). It was assumed,
that the proportion of males in observed samples is 50%.
Exceptions from this rule include Quail, Grasshopper-warbler,
River Warbler and Firecrest. For those species it was
assumed that the proportion of males among recorded individuals
is 100%. For some species (Marsh-harrier , Montagu's
Harrier, Kestrel, Common Crane) estimates of sex
ratio were available from other sources and were applied
accordingly. Occupancy was estimated as the percentage
of plots where the given species was present in relation to
224