Invite the starling to help the greenkeeper


The project “Invite the starling to help the greenkeeper” was initiated as a collaborative work between Sydsjællands Golfklub, Dansk Golf Union and DOF (Dansk Ornitologisk Forening)-Birdlife Denmark in 2018. We prepared and erected ~100 nest boxes, and placed them all over the golf course. All were numbered and georeferenced via the Turfgrass app. We recorded all breeding birds and ringed juvenile starlings and found that 45 successful clutches in 2019 produced on average 5.0 nestlings per clutch. This proves that the golf course provides conditions that are sufficient for the starling to produce successful clutches, with an estimated more than 100 kg prey removed from the grass.

We found marked differences between the number of foraging starling in different parts of the golf course and its surroundings where they foraged during the season. They foraged mainly on the fairway and often also in the semi-rough (there is no rough on this golf course), but rarely on the greens. In 2019, Sydsjællands Golf Club hosted a successful guided bird trip “Birds at golf courses” for local people on one evening in May. This was led by ornithologists from the local branch of DOF-Birdlife Denmark (DOF Storstrøm). Besides birdwatching, the event gave the
opportunity for interaction between members of the two organisations, to talk about the new initiatives at the golf course.

In order to study invertebrates in the turf layer, an additional project was included: “What do starlings eat at the golf course?” To see what the starlings preyed upon, samples of the turf were extracted in transects from the green to the semi-rough. A large number of different invertebrates were found, but only earthworms and cranefly larvae were present in sufficient biomass to be of importance for starlings.
The number of prey items decreased during the breeding season, but the items present increased in size at the same time, so the biomass for starlings increased. The number of earthworms per m2 of the fairway was more than twice that in the semi-rough, with none in the greens. The number of larvae was lower than expected in 2019. Despite no comparable data, the problem with larvae was assessed to have been reduced significantly due to the help from the starlings.

Project objectives

  • The main idea behind this project is invite starlings to settle on golf courses. This bird species preys upon larvae of insects such as craneflies in lawns and fields. It may thereby help the greenkeeper by performing biological control to remove larvae from the turf.
  • This pilot project aims to identify parts of the golf course and the surrounding habitat used by foraging adult starlings during the breeding period.
  • The aim is to attach high precision GPS-loggers to around five starlings, to learn which habitat they prefer and how far from their nesting site they forage.
Henning Heldbjerg

Henning Heldbjerg, DOF-Birdlife Denmark, Vesterbrogade 140, 1620 Kbh V, Denmark

Category: Multifunctional golf facilities
Status: Finished
Project period: May 2018 - October 2019

Fundings (kSEK)

Funding (ksek)        2018          2019              total

STERF                         90            10                    100
Other sources              90             0                      90
Total                        180           10                    190