Colony- and age-specific seasonal dispersal of Herring Gulls Larus argentatus breeding in The Netherlands

Abstract

The Herring Gull population in The Netherlands went through phases of exploitation, protection, persecution and again (partial) protection during the nineteenth and twentieth centuries. The numbers of breeding pairs peaked in the 1980s at approximately 90,000 pairs, at which point a colour-ringing campaign was organised to evaluate dispersal and distribution patterns. Herring Gulls were ringed as chicks, predominately near-fledglings, in 12 colonies in 1986 (1,247 individuals), 13 colonies in 1987 (1,354 individuals) and 14 colonies in 1988 (1,396 individuals). Between 1986 and 2009, of the 3,997 Herring Gull chicks colour-ringed, 3,124 individuals (78.2%) were seen and reported at least once, while 453 (11.3%) were recovered dead. In total, 86,247 ring-readings of living gulls were received and processed, originating from 1,358 locations by 868 observers. One-fifth (20.5%) of all sightings originated from the home-ranges (areas within a radius of 5 km around the ringing place). Only 691 sightings (0.8%) were reported at over 300 km from the natal colony (10.7% at 6-10 km, 8.9% at 11-25 km, 17.7% at 26-50 km, 22.9% at 51-100 km, 14.4% at 101-200 km and 4.1% at 201-300 km). Colony-specific differences in travelling distance, dispersal rate and direction of movements suggest a grouping of colonies in three areas: (1) eastern Wadden Sea islands (Rottumeroog-Vlieland), with significantly higher dispersal rates and movements mostly towards the south-west to south-east; (2) Texel and the four colonies along the mainland coast (Callantsoog-Wassenaar), with shorter mean range and movements mostly to the south; (3) colonies in the Delta area (Europoort-Saeftinghe), with rather short range movements and dispersal in many directions. The maximum distance travelled did not vary much between adults, immatures and juveniles, but the timing of outward and return movements was different for each of these age categories. Adult birds reached their greatest mean distances on average 1 month earlier than immatures, which in turn arrived at this point 1 month earlier than juveniles. These age-specific differences were enhanced in the spring, when birds were moving towards the (natal) colonies, but when adults moved on average closer and 2 months ahead of immatures, which in turn moved earlier and closer to the natal home-range than juveniles. With reference to findings from other studies in other European countries, Herring Gulls breeding in The Netherlands occupies a mid-position between dispersive and sedentary tendencies.

Apparent Survival and Fecundity of Sympatric Lesser Black-Backed Gulls and Herring Gulls with Contrasting Population Trends

“…Lesser Black-backed Gulls are migratory, wintering generally several thousands of kilometres south of the breeding grounds (in this case mostly at the Iberian Peninsula and in NW Africa; Camphuysen et al 2009, Hallgrimsson et al 2012. Herring Gulls are dispersive or short-range migrants, wintering mostly in The Netherlands, in Belgium or in northern France, and migrating hundreds of kilometres rather than thousands (Camphuysen et al 2011). It is unclear how long distance migration or short-distance dispersal would influence annual adult survival differently.…”

“…Nonetheless, frequent observations were made within the colony to minimise identification error and to reduce the possibility of missing ringed individuals. Sightings were also reported outside the colony, mostly by dedicated birdwatchers, both in The Netherlands and elsewhere in Europe and NW Africa (Camphuysen et al 2011). Only sightings within the colony were used to estimate apparent adult survival, but the other reports were used to check whether particular individuals were still alive even if there were no sightings within the colony (Table 1).…”

Age and season predict influenza A virus dynamics in urban gulls: consequences for natural hosts in unnatural landscapes

“…Juveniles are the most likely to undertake long‐distance, exploratory migrations (Drury and Nisbet 1972, Hebert 1998, Camphuysen et al. 2011, Jorge et al. 2011) where they may encounter other gull species (Guinn et al.…”

“…The peak in viral prevalence in newly fledged gulls has important implications for the spread of pathogens to new hosts and species during the migratory season (Bogomolni et al 2008). Juveniles are the most likely to undertake long-distance, exploratory migrations (Drury and Nisbet 1972, Hebert 1998, Camphuysen al. 2011, Jorge et al 2011 where they may encounter other gull species (Guinn et al 2016), shorebirds, and ducks (Krauss et al 2004).…”

Seabirds? : what seabirds? : An exploratory study into the origin of seabirds visiting the SE North Sea and their survival bottlenecks

“…Migration and dispersal patterns, as far as these can be followed from land-based re-sightings of colour rings, and parameters such as annual survival, site-fidelity and recruitment are thus becoming increasingly better known. Lesser Blackbacked Gulls and Herring Gulls Larus argentatus have been colour-ringed in various colonies in The Netherlands since 1986 (Camphuysen 2008;Camphuysen et al 2011 Colour ringing data may allow an analysis of (added) mortality from human pressures, if these act on the colony studied and if the effects are large enough to be detected against the background of variance in the census data. Sufficient numbers of birds need to be ringed and re-sighted for a markrecapture analysis.…”