Tuesday 17 December 2019

Loafing gulls

 Gulls spend a good portion of their days doing what is known as 'loafing', in open areas of good visibility: playing fields, beaches, but also on water and on ice in frozen lakes, the same sites are chosen year on year. These loafing areas are different from night roosting sites. At loafing sites gulls appear relaxed: some sleep - head under wing - others sit or stand watching around, others preen. Immatures may play with objects such as sticks or leaves. Loafing areas are common areas, and tend to be quiet, with little or no squabbling or aggressive behaviour, often with several species mixing in the same area. Individuals come and go, commuting to their feeding areas, unless a disturbance provokes a sudden communal flight. On the coast, the number of individuals in a loafing area follows a tidal cycle - as low tides expose food resources the gulls move away the loafing area to feed- and also time of the year. Tidal influence in sleeping is highly prevalent in wading birds, which strongly depend on exposed shores for feeding. A study in Herring Gulls suggest that they have a dual sleeping pattern, with the proportion of sleeping gulls peaking at midnight and at midday. This may be a common pattern with urban gulls or away from the coast, where food is less related to tidal fluctuations.
A mixed flock of Black-headed gulls, Common Gulls and Herring gulls loafing on a rise on a local park.
Loafing gulls allow good opportunities to check individuals for plastic rings, as shown by this preening Common Gull.
A group of Common Gulls loafing on ice on a frozen pond of (16/1/2013)

More information
Shandelle M. Henson, James L. Hayward, Christina M. Burden, Clara J. Logan and Joseph G. Galusha. 2004. Predicting Dynamics of Aggregate Loafing Behavior in Glaucous-Winged Gulls (Larus glaucescens) at a Washington Colony. Auk 121, 380–390.

Cooke, F. and Ross, R. K. 1972. Diurnal and Seasonal Activities of a Post-Breeding Population of Gulls in Southeastern Ontario. Wilson Bull. 84, 164–172.

Galusha, J. G., JR and Amlaner, C. J., JR. 2008. The effects of diurnal and tidal periodicities in the numbers and activities of Herring Gulls, Larus argentatus, in a colony. Ibis 120, 322–328.

2 comments:

  1. Thanks, I've learnt a new word. I might have described idle gulls as 'loafing' as a joke, but I had no idea it was a technical term.

    ReplyDelete
  2. Thank you Ralph, happy to be of help!

    ReplyDelete

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