2021 Swallow Nest Box Status

Status of Swallow Nest Boxes at Buttertubs West Marsh to 31 May 2021.

Number of boxes: 36
Number of boxes with eggs: 29 (81%)
Number of eggs laid: 151
Mean clutch size (range): 5.2 (1-7)
Number of eggs hatched (% eggs hatched): 71 (47%)
Number of nestlings banded (% nestlings banded): —
Number of females banded: 27
Number of males banded: 1
Number fledged (% nestlings fledged): —
Fledging rate (young per pair): —

Summary of Tree Swallow nesting productivity at Buttertubs West Marsh during 2016-2020.

Parameter 2016 2017 2018 2019 2020
Number of boxes3037303036
Number of boxes with eggs (% of boxes with eggs)20
(67%)
22
(59%)
24
(80%)
21 (70%) 29
(81%)
Number of eggs laid115138135141193
Mean clutch size (range) 5.0
(2-6)
5.1
(1-7)
5.0
(1-7)
5.0
(2-7)
5.1
(2-7)
Number of eggs hatched (% eggs hatched)78
(68%)
82
(59%)
115
(85%)
106
(75%)
148
(77%)
Number of nestlings banded (% nestlings banded) 68
(87%)
69
(84%)
105
(91%)
97
(92%)
92
(62%)
Number fledged (% nestlings fledged)46
(59%)
52
(63%)
62
(54%)
84
(79%)
76
(51%)
Fledging rate (young per pair)2.12.02.33.02.0