Starling Sturnus vulgaris

5.1.13Starling Sturnus vulgaris

North European starling populations have suffered pronounced declines in recent decades but the species is still common and widespread across most of the Zone (Table 5.). Starlings depend on open areas, such as grassland, field crops or floodlands, for foraging, but also need suitable holes (natural or man-made) for nesting. Through more than a century, the starling benefited from the clearing of forests, establishment of human settlements and spread of agriculture in northern Europe. Its range and population size probably reached a maximum during the 1960s, after which most populations have declined (Rintala & Tiainen 2007, 2008). Agricultural intensification in general, and structural changes within farmland in particular, may well be the main reasons for the decline. At least in Finland, the major driver was probably the dramatic decline of dairy husbandry and the consequent decrease in availability of good Starling habitat (Rintala & Tiainen 2007, 2008).

The species is generally migratory within the Zone, albeit with an increasing tendency for urban starlings to remain resident in South Sweden, Denmark and southern and western Norway, especially in mild winters (Snow & Perrins 1998). Winter quarters are mainly in the Channel area.

Starlings are associated with open country, particularly grasslands. They breed in open forest, woodland edge, around farms, in villages and in urban areas, but always near grassland (including lawns, golf courses etc.).

Body weight somewhat variable, ♂ mostly 70–90, ♀ mostly 60–90 g (Snow & Perrins 1998). Mean body weight of the smaller sex (♀: 75 g) may be used for risk assessment.

According to English data, the daily energy expenditure is highest in spring (c. 290 kJ/day) and lowest in summer (c. 200 kJ/day) (Christensen et al. 1996). The intake of captive adult starlings was 210-265 kJ/day if kept on animal food. Alternatively, the energy expenditure can be calculated allometrically using the equation for passerine birds in accordance with the formula in Appendix G of the EFSA Guidance Document (EFSA 2009).

The diet consists of animal as well as vegetable matter throughout the year, but the relative proportions vary with the annual cycle (and are parallelled by changes in the length of the intestine). Invertebrates dominate in spring and summer while vegetable matter comprises a high proportion of the diet during autumn and winter. The proportion of vegetable matter in the diet is less than 50 % from April to June and 50-95 % during the rest of the year (Christensen et al. 1996). In a Polish study of adult diet, 85 % of all food items were animal during February-September (Gromadzki 1969), and in a similar Czech study, 69 % of all food items were animal in March-November (Havlin & Folk 1965), see also Table 15. In both of these studies, almost no vegetable food items were taken between March and June.

Being a partial frugivore, the starling is relevant for the following scenarios:

• 
  strawberries, BBCH 60-89
  
• 
  fruit trees (cherry, plum), canopy directed applications during BBCH 60-89
  

The starling would also be relevant in grassland, which is its main foraging habitat, but here smaller species, such as yellow wagtail, are more worst case.

For those elements of the diet which are obtained from the ground, i.e. seeds and ground arthropods, interception in the crop or canopy shall be taken into account.