VEEN J (1980) Breeding behaviour and breeding success of e colony Little Gulls Larus minutus in the Netherlands. LIMOSA 53 (3): 73-83.

The reclaiming of the Lauwerszee area in 1969 had led to a sudden increase of the number of Little Gulls vis' iting the area during spring migration (maximum 566 birds in May 1978). Groups of Little Gulls visiting the new polder consist of juveniles (second calender-year) and older ones (third calender-year and older). Figure 2 shows that the juveniles visit the area somewhat later than the older birds. From 1972 onwards an increasing number of Little Gulls has nested in different places within the area (table 1, figure 3). Nest-site selection seemed importantly influenced by the structure of the vegetation, the occurrence of predators and the presence of breeding habitat of the Little Gulls in the Lauwerszee area can be regarded as atypical for the species.
      Data on laying date, clutch 'size and laying interval are given in table 2, 3 and 4. An investigation of the plumage pattern of the breeding birds has revealed that between 1975 and 1978 nearly all females and the majority of males were first-time breeders (figure 5, 6). This means that the Little Gull colonies in the Lauwerszee area are inhabited by new birds each year. Breeding success has been extremely low in all years (table 5). In general, eggs hatched succesfully, but nearly all chicks were preyed upon by Black-headed Gulls and, to a lesser extent, by Herring Gulls and Kestrels (table 6). Only in 1974 and 1978 a small number of chicks fledged. The high proportion of Little Gull chicks robbed by Black-headed Gulls is of special interest, since Little Gulls tend so seek the company of Black-headed Gulls for breeding. The behaviour is also known from other Little Gull colonies and suggests that nesting in the neighbourhood of a Blackheaded Gull colony is advantageous. The extremely low breeding results of the Little Gulls in the Lauwerszee area have been related to the age of the breeding birds. It is hypothesized that a lack of breeding experience causes that the breeding birds often leave their young unguarded. This makes the chicks highly vulnerable to predation, especially in the open breeding habitat in the Lauwerszee area. Little Gull Hydrocoloeus minutus = Larus minutus

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