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Vol. 53, 2014
Long-term population trends reveal increasing importance of a
Mediterranean wetland complex (Messolonghi lagoons, Greece) for
wintering waterbirds
Vasilios
Liordos1*, Fotis Pergantis2, Iris Perganti2 and Yannis Roussopoulos3
1Department
of Forestry and Natural Environment Management, Eastern Macedonia and
Thrace Institute of Technology, 1st km Drama-Mikrohori, Drama 66100,
Greece
2Ornithological Surveys, Aitoliko 30400, Greece
340 Almyraki str., Messolonghi 30200, Greece
Abstract
Background: The aim of this study
was to present the first detailed analysis of long-term population
estimates and trends of waterbirds wintering at Messolonghi lagoons,
one of the largest Greek wetlands, during 1982 to 2012, using
TrendSpotter software.
Results: The wetland supported on average 63,054 ±
22,241 (SD) birds (range 29,630 to 109,795), with waterfowl and their
allies being the most abundant group, by both species and numbers. Over
70% of the 28 most abundant species (19 waterfowl, 9 waders) were
increasing (14 waterfowl, 6 waders), 4 waterfowl were decreasing, 3
species remained stable (1 waterfowl, 2 waders) and 1 wader could not
be assessed. In total, waterfowl increased by 2%, waders increased by
4% and the overall species assemblage increased by 2.2% over the
31-year period. The wetland is of international importance for
waterbirds in general and for Eurasian wigeon Anas penelope and Kentish
plover Charadrius alexandrinus specifically. In
addition, 7 other species (6 waterfowl, 1 wader) currently exceed the
1% flyway population threshold and could also be considered as of
international importance in the future.
Conclusions: Long-term increases in
the numbers of most waterbirds were detected, and internationally
important populations were identified, thus highlighting Messolonghi
lagoons' increasing significance for wintering waterbirds over the past
31 years. Piscivores (i.e. pelicans, cormorants, herons and egrets),
flamingos and small waders showed the strongest increases in numbers.
In contrast, common pochard Aythya
ferina and tufted duck Aythya fuligula showed the greatest
declines. In most species, population trends followed those occurring
at the flyway level, suggesting that regional or international rather
than local factors may be mainly responsible.
Key words: Midwinter counts; Waterfowl;
Waders; Structural time series analysis; Ramsar criteria.
*Correspondence: E-mail: liordos@yahoo.com
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