Bird monitoring results
The data on breeding distribution, abundance and phenology of birds occurring in the area of Sečovlje Salina (1878-2009) have been contributed by a large number of ornithologists and observers. All published data as well as numerous still unpublished records from personal ornithological notebooks have been gathered. Some of the data, however, have not been accessible, in spite of doing our best to obtain them.
From the area under consideration, a multitude of data from the wintering period (from November to March), spring migration period (March-May), breeding period (May-July), post-breeding period (July and August) and autumn migration period (September-November) was gathered for the wider 1973-2009 period. Data covering the 1983-2002 period have been collected more or less systematically, while those concerning the 2004-2009 period are the result of a regular weekly bird monitoring carried out in the area within the framework of Sečovlje Salina Nature Park's management.
In the 1983-2009 period, a total of more than 1,500 fieldwork days were conducted. 16,800 faunistic data were collected (datum = record on a certain species in a certain place at a certain time), which speak of 751,102 observed individuals. In this contribution, we are dealing with 292 species, which were registered at least once in the area of Sečovlje Salina during the 1870-2009 period. 39 of them are random species, with the data for 9 of them originating from the end of the 19th century (historical records); for 7 species among the latter, a very little chance exists that they would ever occur here again. One species is a wild domestic bird (domestic pigeon).
The most often observed species in the area of Sečovlje Salina was Little Egret (1,133 observations), followed by the Yellow-legged Gull (1,131 observations) and Mallard (928 observations). The Yellow-legged Gull was the most abundant species (390,608 individuals), followed by the Coot (40,054 individuals) and Barn Swallow (38,207 individuals).
In the area of Sečovlje Salina, a total of 53 species have bred so far, only 24 of them in the salt-pans themselves. 39 species are known to breed regularly, with further 6 species breeding only occasionally.
11 species (Falco tinnunculus, Fulica atra, Actitis hypoleucos*, Otus scops, Athene noctua, Anthus campestris, Phoenicurus ochruros, Saxicola rubetra, Saxicola torquatus, Acrocephalus palustris, Corvus monedula) have ceased to breed in the last 10 years in the area under consideration, while 3 totally new species began to breed here regularly in the same period (Tadorna tadorna, Recurvirostra avosetta, Tringa totanus). The Bee-eater Merops apiaster bred here only in 2005.
We have not succeeded to confirm the breeder status for 4 species (Anas querquedula, Anas clypeata, Ixobrychus minutus, Dryocopus martius). 5 species are nonindigenous (Dendrocygna bicolor, Cygnus atratus, Aix galericulata**, Colinus virginianus, Psittacula krameri).
153 recorded species were overwintering in the area, 123 of them in December and 126 in January. 70 species regularly overwinter in the area of Sečovlje Salina, 30 species do not spend the winter there each year, while 53 species are winter visitors.
Spring passage in the area of Sečovlje Salina takes place predominantly between the end of February and beginning of June. In the 1983-2009 period, 213 species were recorded, while during the autumn migration (which takes place between August and November) in this same period 211 species were registered. Many species stop here both during migration and in the overwintering period. 134 species occur regularly during the migration period.
10 of all registered breeders are species of national significance. These are species that in the area of Sečovlje Salina Nature Park hold 10% or more of the entire national population. i.e.: Shelduck Tadorna tadorna, Black-winged Stilt Himantopus himantopus, Avocet Recurvirostra avosetta, Kentish Plover Charadrius alexandrinus, Redshank Tringa totanus, Yellow-legged Gull Larus michahellis, Little Tern Sternula albifrons, Common Tern Sterna hirundo, Fan-tailed Warbler Cisticola juncidis and Cetti's Warbler Cettia cetti.
No less than 87 of all registered species have been inscribed on the list of birds from Annex I of the Bird Directive and migrating species from Article 4. No less than 30 of them are triggering (qualifying) species, for which SPA sites are stipulated. 29 species can be found on the Red List of Breeding Species.
* It was already Gregori (1976) who referred to the Common Sandpiper as a possible breeder, given that he had observed separate individuals in the breeding season. Škornik et al. (1990) and Makovec et al. (1998), too, cite the Common Sandpiper as a breeder owing to their observations of this species in the breeding season, but they never managed to find its nest. The more recent observations, however indicate that in all likelihood we can delete Common Sandpiper from the list of Sečovlje Salina breeders.
** Although the Mandarin Duck was introduced to Europe as early as in 1740, some sources still refer to it as a nonindigenous species, while others have included it on their lists as a species that occurs in Europe as a visitor and even breeds in places (BirdLife, 2010).