Hybrid between House- and Tree Sparrow
Hybrids between House Sparrow Passer domesticus and Tree Sparrow P. montanus are rare. According to J. I. Summers-Smith, cites in Sheppard (1995) there should be 47 records + 4 new ones being received in the time the paper was written.
Most features of my male hybrid are more like the Tree Sparrow and that is in agreement with Cordero (1991) who states that male hybrids have more similarities with Tree Sparrow and females with House Sparrow.
CN 2921
Passer domesticus x montanus male ad
10 January 1971, Kalundborg 55.41N 11.06E, Denmark
wing (max) 74.28, culmen 12.64, tail 55.72
both testes 1.7 x 1.1mm, body weight 28.4g, fat
breastbone with shoulder girdle:
From apex carina to the end of breastbone 22.86
From distal end of coracoid to the end of breastbone 35.23
Length between the two trabecula lateralis 16.33
Length of scapula 20.61
A comparison with the wing, culmen and tail measurement given by Summers-Smith (1988) showed that the hybrid was near the average between the two with a little more to the Tree Sparrow side.
A comparison of four measurements from the breastbone and shoulder girdle between a random closed 4 House Sparrow males and 4 Tree Sparrow males compared with the hybrid gave the opposite result as all the measurements were nearer that of the House Sparrow.
Description of the plumage
Top of head brown mixed with grey, chin whitish with a diffuse dark area, side of neck intensive brown with a white collar, mantle a tint more red-brown compared with a House Sparrow. Wings with two white wing-bands and a conspicuous pale brown area near base of primaries. Underparts paler than a House Sparrow and under tail-coverts pale brown edged paler, tail feathers a little narrower than in a House Sparrow.
References
Cordero, P. 1991: Phenotypes of adult hybrids between House Sparrows Passer domesticus and Tree Sparrow Passer montanus. Bull. Brit. Ornithol. Club 111: 44-46.
Sheppard, R. 1995: Hybrid Tree x House Sparrow in County Donegal. Irish Birds 5 (3): 319-320.
Summers-Smith, J. D. 1988: The Sparrows. T & A D Poyser, Calton.
Table 1
The measurements are taken from Summers-Smith (1988), number measured
not recorded in his work.
|
|
Species wing |
mean wing range |
tail mean |
tail range |
culmen |
mean culmen range |
|
domesticus |
80.4 |
67-85 |
59.6 |
55-64.5 |
12.4 |
10-14 |
|
montanus |
71.1 |
66-76 |
53.6 |
52-58 |
13.5 |
13-14 |
|
average of both species |
75.8 |
|
56.6 |
|
13.0 |
|
|
hybrid |
74.3 |
|
55.7 |
|
12.6 |
|
Table 2
Skeletal measurements of four random closed House Sparrow
and Tree Sparrow males.
|
|
Breastbone length from apex carina to anterior end. |
From distal end of coracoid to apex carina |
Length between the two trabeculae lateralis |
Length of scapula. |
|
P. domesticus 1575 |
22.52 |
36.13 |
17.35 |
21.17 |
|
P. domesticus 2196 |
22.14 |
35.21 |
17.14 |
20.78 |
|
P. domesticus 2293 |
21.47 |
33.55 |
15.23 |
20.66 |
|
P. domesticus 1317 |
22.83 |
36.75 |
16.84 |
21.75 |
|
average |
22.24 |
35.41 |
16.64 |
21.09 |
|
P.montanus 2206 |
21.13 |
34.03 |
15.42 |
18.26 |
|
P. montanus 2594 |
20.17 |
33.80 |
16.36 |
20.08 |
|
P. montanus 1458 |
19.77 |
33.32 |
14.84 |
19.39 |
|
P. montanus 1707 |
21.76 |
34.91 |
15.76 |
20.00 |
|
average |
20.70 |
34.02 |
15.60 |
19.43 |
|
hybrid 2921 |
22.86 |
35.23 |
16.33 |
20.61 |