Record of proceedings

Download 380.83 Kb.

Page	10/14
Date	02.02.2017
Size	380.83 Kb.
	#15482

1 ... 6 7 8 9 10 11 12 13 14

References

Altringham, J.D., O'Brien, S. & Julian, S. (1994) Feeding ecology of the little owl (Athene

noctua) an an upland site in northern England. Naturalist 119: 81-94.

Bevan, G. (1964) The food of tawny owls in London. London Bird Report 29: 56-72. Brown, R., Ferguson, J., Lawrence, M. & Lees, D. (1987) Tracks and Signs of the Birds of Britain and Europe. Christopher Helm, London.

Macdonald,A.W.(1976) Nocturnal observations of tawny owls (Strix aluco) preying upon

earthworms. Ibis 118: 579-80.

Mead, C. (1987) Owls. Whittet, London.

Southern, H.N. (1954) Tawny owls and their prey. Ibis 96: 384-410.

Wardhaugh, A.A. (1983) Owls of Britain and Europe. Blandford, Poole.

Yalden, D.W. (1977) The Identification of Remains in Owl Pellets. The Mammal Society,London,

Table 1:Monthly Record of Pellets Collected and Presence of Owls at Roost

Collection Date	No. of Pellets	Volume (cm³)	No. of Owls Seen

24. 1. 93	17	-	1
19. 2. 93	12	-	2
27. 3. 93	16	127	0
21. 4. 93	20	138	0
22. 5. 93	14	77	0
21. 6. 93	7	39	0
22. 7. 93	16	104	0
22. 8.93	0	0	0
25. 9. 93	1	5	0
25.10.93	1	4	2
20.11. 93	6	38	2
20.12. 93	14	82	2
22. 1. 94	7	29	1
20. 2. 94	6	30	0
26. 3. 94	32	187	1
24. 4.94	15	103	0
23. 5. 94	1	6	0
22. 6.94	1	3	0
25. 7.94	1	6	0
22. 8. 94	0	0	0
25. 9.94	0	0	0
26.10.94	0	0	0
19.11.94	0	0	0
22.12. 94	1	6	0
TOTAL	159	984	-

Table 2:Monthly Record of Prey Items

Collection Date	Bank Vole	Short-tailed Vole	Wood Mouse	Common Shrew	Pygmy Shrew	Other
24. 1. 93	26	2	18	0	1	1 bird
19. 2.93	12	0	5	0	0
27. 3. 93	14	4	8	1	0
21. 4. 93	9	5	4	2	1	1 probable rat
22. 5.93	4	5	2	3	0
21. 6.93	2	3	2	0	0
22. 7.93	9	2	3	2	0
22. 8.93	0	0	0	0	0
25. 9. 93	1	0	0	0	0
25.10.93	1	0	0	0	0	1bird
20.11. 93	7	2	0	0	0
20.12. 93	7	1	8	2	0
22. 1.94	4	0	1	0	0
20. 2. 94	3	2	1	0	0
26. 3. 94	4	11	6	2	4	1 bird (robin?)
						1 young rabbit
24. 4. 94	4	6	1	2	0	1 probable
						young rabbit*
23. 5.94	0	0	0	0	0
22. 6. 94	0	1	0	0	0
25. 7.94	1	0	0	0	0
22. 8.94	0	0	0	0	0
25. 9.94	0	0	0	0	0
26.10. 94	0	0	0	0	0
19.11.94	0	0	0	0	0
22.12.94	2	0	0	0	0
TOTAL	111	43	59	14	6	rat 1, rabbit 2
						mole 2, bird 3
NO. PER100 cm³ **	7.42	4.17	3.66	1.42	0.61

*Remains of rabbits found in pellets collected on 26.3.94 and 24.4.94 could be from the

same individual but here counted as two.

** For March 1993 to December 1994 inclusive. (Pellet volumes not recorded January and February 1993).

Total number of prey items identified: 241

Number of prey items per 100cm³ (all species): 17.99

Table 3: Summary of Prey Items Identified

Species	Number of Individuals		Mass Represented*
		(%)	g	(%)
Bank vole	111	(46.1)	1776	(43.6)
Short-tailed vole	43	(17.8)	903	(22.1)
Wood mouse	59	(24.5)	1062	(26.0)
Common shrew	14	(5.8)	112	(2.7)
Pygmy shrew	6	(2.5)	24	(0.6)
Mole	4	(0.8)	140	(3.4)
Probable Rat	1	(0.4)	60	(1.4)
Probable Rabbit	2	(0.8)	-	-
Bird	3	(1.2)	-	-

Total	241	4077	-	-

* Based on figures for mean mass of each prey species provided in Yalden (1977)

For rabbit and birds there were insufficient remains to estimate size and therefore mass

hence these species were not included in the calculation of percentage mass.

Table 4:Prey Items Identified in Tawny Owl Pellets from elsewhere in the Cleveland Area

Site

Date

Prey Items

Comments

Cross Wood, Flatts Lane

(NZ 543169)

Spring
1967

short-tailed vole 1
bank vole 3

bird 1

Roost site approx. 0.6 km NW of site of present study; beech tree cavity. Unrecorded small no. of pellets.

Wood at Ormesby Hall

(NZ 530171)

5.4.1971

wood mouse 4
common shrew 1

house sparrow 10

Roost in a yew tree. Unrecorded small no.of pellets.

Plantation near incline, Ingleby Greenhow

(NZ 602025)

2.4.1978

short-tailed vole 2
bird 5

Roost in a holly tree. Unrecorded small no. of pellets.

Wood at Teesside High School
(NZ 425149)

9. 6.93

birds 2

48 cm³ of pellets

5. 7.93

birds 4

50cm³ of pellets

6.12.93

wood mouse 4

50 cm³ of pellets

brown rat 2

Pellets collected from a variety of sites within the wood

.

Download 380.83 Kb.

Share with your friends:

1 ... 6 7 8 9 10 11 12 13 14