Artificial floating islands for nesting black-throated divers Gavia arctica in Scotland: construction, use and effect on breeding success

  • Published source details Hancock M. (2000) Artificial floating islands for nesting black-throated divers Gavia arctica in Scotland: construction, use and effect on breeding success. Bird Study, 47, 165-175.


This study is summarised as evidence for the following.

Action Category

Provide artificial nesting sites for divers/loons

Action Link
Bird Conservation
  1. Provide artificial nesting sites for divers/loons

    A replicated before-and-after trial on lochs in Scotland between 1980 and 1997 (Hancock 2000) found that installing 63 nesting rafts in arctic loon (black-throated diver) Gavia arctica territories in 1992-5 increased chick productivity of the British population by an estimated 44% (from approximately 0.24 large chicks/territory to 0.35 large chicks/territory, 60-100 territories monitored each year), with an estimated 170% increase in the 44 territories where rafts were used (representing approximately 25% of the British population). Rafts consisted of a 3.6 x 2.4 m polystyrene rectangle with sides sloped to allow access from the water. They were covered in hessian, netting and turf and anchored to concrete blocks in shallow (1-3 m) water close to natural nest sites known to be susceptible to flooding and hidden from public roads to avoid illegal egg collecting. Rafts lasted at least ten years with annual maintenance.


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