BOELE A & WINDEN E VAN (2012) Glossy Ibis Plegadis falcinellus in The Netherlands: do we notice the population increase in Southern Europe?. LIMOSA 85 (4): 171-178.

Glossy Ibis is a rare non-breeding bird in The Netherlands. Up to and including 1999 records were evaluated by the Dutch rarities committee (cdna). Here we summarise all 217 records of 311 birds from 1867-2011, including accepted records as well as 29 reports from 1867-1999 that never have been evaluated by the cdna.
      Ring recoveries have shown that birds in The Netherlands originated from Hungary (two shot in September 1926) and Spain (singles in 2009 and 2011). The 2011 individual illustrates how easily double records arise: white V02, (ringed in 2010) was seen in Germany, Lithuania and four locations in the northern part of The Netherlands. Other Spanish-ringed birds have been observed in England, Wales, Ireland, Germany and even Trinidad and Tobago, and a Glossy Ibis from the Camargue was observed in the uk. A group of four including a Spanish-ringed bird (white 01N1) was observed to travel between Norfolk, uk, and Lower Saxony, Germany, 600 km to the east, in one day.
      Most birds in The Netherlands have been recorded in the western and northern provinces (Fig. 1). Most records (86%) concerned solitary birds. Particularly large groups were seen in September 1994 (10 first-years, Texel, Noord-Holland) and October-November 1932 (at least 14, Weert, Limburg). The seasonal pattern has changed, with the period of maximum occurrence shifting from October-November during 1867- 1988 to September-October in 1989-2001 and August-September in 2002-2011 (Fig. 2). In spring both relative and absolute numbers have increased, with a small peak in April-June comprising 26% of all birds since 1989 (Figs 2, 4).
      Since 1986, Glossy Ibis has been recorded annually (except in 2008) and numbers are increasing (Fig. 3). Preliminary results for 2012 show a further increase with probably more than 20 birds until July (possibly including some double records). This partly reflects the increasing number of birdwatchers and quality of recording, but will also be the result of the spectacular increase of breeding populations in Spain and Southern France. After almost a century of absence the species reappeared as a breeding bird in Spain in the 1990s and the population increased rapidly to more than 3000 pairs in 2009. The high reproductive output in Spain is seen as a key driver of this species' spread into France and Algeria. In the Camargue, the population increased from 14 pairs in 2006 to 518 in 2011, while in 2011 the first solitary breeding pairs were recorded in Landes, S. France and at Lac de Grand-Lieu, W. France. The latter location is just as far from the nearest large colony (Camargue, 600 km) as from the Dutch border. Glossy Ibis probably never bred in The Netherlands, but this might change in the next decades.

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