Jussi Murtosaari / Eurasian tree sparrow (Passer montanus) in winter, Muurame, Keski-Finland, January. / Central Finland, Finland, January.

Jussi Murtosaari / Eurasian tree sparrow (Passer montanus) feeding on grass seeds, Parikkala, Etela-Karjala / South Karelia, Etela-Suomi / South Finland, Finland. September

Michel Poinsignon / Tree sparrow (Passer montanus) adult perched on snowy branch in winter, Moselle, France. December.

Fabrice Cahez / Eurasian tree sparrows (Passer montanus) perched on barbed wire, Vosges, France, March.

Zoltan Nagy / Eurasian Tree Sparrow (Passer montanus). Panet, Romania. June

Zoltan Nagy / Eurasian Tree Sparrow (Passer montanus) Panet, Romania. June.

Jussi Murtosaari / Eurasian Tree Sparrow (Passer montanus) central Finland, March.

Jussi Murtosaari / Eurasian Tree Sparrow (Passer montanus) and a House Sparrow (Passer domesticus) feeding on seeds, South Karelia, southern Finland, September.

Fergus Gill / Tree sparrow (Passer montanus) perched on a branch of Hawthorn blossom (Crataegus monogyna) Perthshire, Scotland. June 2013

Fergus Gill / Tree sparrow (Passer montanus) perched on a branch of Hawthorn blossom (Crataegus monogyna) Perthshire, Scotland. June 2013

Fergus Gill / Tree sparrow (Passer montanus) feeding a fledgling on a branch of Hawthorn (Crataegus monogyna) blossom, Perthshire, Scotland. June 2013

Fergus Gill / House Sparrow (Passer domesticus) (left) and Tree sparrow (Passer montanus) (right) perching on a branch of Hawthorn (Crataegus monogyna) blossom. Perthshire, Scotland. June 2013