Abstract Common Iand-birds in a rural suburban garden, Wellington, New Zealand, were counted for 10 minutes twice an hour, twice a month for 2 years, from dawn to dusk. The birds&apos; behaviour sometimes changed or they entered or left the study area during the day; so there is no ided time of day for counting buds

John A Gibb

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184 Notornis, 2000, VoZ. 47: 184-191 
0029-4470 O The Ornithological Society of New Zealand, Inc. 2000 
Dawn to dusk counts of common or garden birds, 
Wellington, New Zealand 
JOHN A. GIBB 
3 Wairere Road, Lower Hutt, New Zealand 
Abstract Common Iand-birds in a rural suburban garden, Wellington, New Zealand, were counted for 10 minutes twice an hour, 
twice a month for 2 years, from dawn to dusk. The birds' behaviour sometimes changed or they entered or left the study area during 
the day; so there is no ided time of day for counting buds. 
Gibb, J.A. 2000. Dawn to dusk counts of common or garden birds, Wellington, New Zealand. Notornis 47(4): 184-191. 
Keywords common buds; gardens; dawn-dusk; counts; conspicuousness 
INTRODUCTION 
Calquhoun (1940) deplored ignorance about birds' 
conspicuousness yet he ignored diurnal variation. Several 
studies (e.g., Hartley 1953; Gibb 1954) have recorded 
bird behaviour in the morning supposing that it would 
remain unchanged throughout the day. However, birds 
are not equally conspicuous all day (e.g., Grey 1927). 
For example, a rock pipit (Anthus spinoletta) watched 
for most of a few days in Britain spent much time feeding 
on foods exposed by the tide (Gibb 1956). Gibb (1955) 
recorded when adult tits (Paridae) fed their nestlings (cf. 
Gurr 1954). Diurnal variation in activity is rarely 
measured in New Zealand, so I recorded it in a few 
common birds from 1993 to 1995. This information 
should especially assist those planning to count birds. 
in 10-min periods (Table 1; Gibb 2000). As before (Gibb 
19%), I noted which birds were first seen or first heard. 
Seasonal fluctuations resembled those already described 
(Gibb 2000). 
To analyse wind speed at different times of day, the 
day was divided into four periods: early morning, late 
morning, early afternoon, late afternoodevening. Exact 
times varied seasonally. Hourly records of wind speed 
were grouped as either Calm (Beaufort 0- 1) or Windy. 
Times of day (New Zealand Standard Time) refer to 
Table 1 Total counts h-I (New Zealand Standard Time); 
years pooled. 
Number of counts 
lime Spr Sum Aut Win 
STUDY AREA 
I first counted birds in the Western Hutt hills (41°12'S, 
174"5S'E), from 1981 to 1992 (Gibb 2000). The 
vegetation here is mainly native and exotic trees and 
shrubs. There is little cultivated land and there are no 
lawns or fruit trees. 
METHODS 
To count birds I sat outside facing west. Twice a month 
for 2 years, I spent 20 min h-' fromdawn to dusk counting 
Received 20 February 1999; accepted 23 August 2000 Total 3 20 360 290 252 
Dawn-dusk counts of common birds 185 
the 60 min following the hour stated: thus '0600' spans detected when singing (spring-summer) from 0600-0759 
0600-0659 h. Spring includes Sep-Nov, summer Dec-Feb, h (Table 2). 
autumn Mar-May, winter Jun-Aug. FANTAIL (Rhipidura fuliginosa). Often fed aerially 
above the canopy in autumn-winter when commonly calm 
RESULTS (Gibb 1996, 2000), especially from 1200-1359 h (Fig. 
6) .  Few were seen during spring-summer when it was 
The birds often windy (Gibb, 2000). Dell (1959) thought that they 
Of 46 species recorded by Gibb (2000), 9 justified hourly 
analysis. Southern black-backed gulls commuted between 
Wellington and Porirua Harbours or elsewhere. 
Kingfishers were present only in spring-summer. 
Silvereyes were commonest when migrating in autumn. 
Starlings roosted elsewhere. The other 5 species seemed 
to be resident. 
SOUTHERN BLACK-BACKED GULL (Lurus dominicanus). 
The number flying over, always against the wind, ranged 
from 0 to >I50 per 10 min. On average, there were more 
in a ~ t ~ m n > ~ ~ m m e r > w i n t e ~ ~ p r i n g  (Fig. 1); and in spring- 
summer more before 1000 h than through the day 
(x2=7.91, ldf, P<0.001), and then more again in the 
evening (x2=18.89, ldf, P<0.001). In autumn-winter more 
were seen before 0800 h than later in the morning 
(x2=10.42, ldf, P<0.001), then more still in the evening 
(x2=9.36, ldf, P<0.001). The two highest counts (>I50 
in 10 min in winter) were both late in the day. This was 
no simple movement to feeding grounds in the morning 
and back in the evening since the birds always flew 
against the wind, presumably returning with the wind 
by a different route. 
& N G ~ S H E R  (Halcyon sancta). Birds first seedheard 
were pooled (Fig. 2). They were often detected early in 
the morning and in the evening (x2=5.29, ldf, P<0.05) 
when noisy. 
NEW ZEALAND PIGEON (Hemiphaga novaeseelandiae). 
Pigeons roosted and bred in the bush here. I saw many 
more 0600-0759 h than later (x2=82.67, ldf, P<0.001), 
probably because some roosting here fed here in the valley 
(Gibb 2000). As Fig. 3 shows, this was less obvious in 
summer when heavy crops of tawa berries, following after 
pigeonwood, kept them here. Evidently pigeons may fly 
far from the roost to feed elsewhere. 
BLACKBIRD (Turdus merula). Common, resident; 7% 
were first heard singing in spring, 18.2% in summer 
(xZ=88.2, Idf, P<0.001) (Fig. 4). None sang in autumn- 
winter. In spring more were first heard singing in the 
afternoon than in the morning (x2=26.22, ldf, P<0.001), 
commonly from 1800-1959 h (x2=6.23, ldf, P<0.05). 
SONG THRUSH (Turdus philomelos). (Fig. 5) Usually 
left all other habitats to breed in the bush, but I think this 
unlikely. More information is needed to investigate 
possible diurnal changes in feeding (cf. Moeed & 
Fitzgerald 1982). 
SILVEREYE (Zosterops lateralis). As elsewhere (Gibb 
1996,2000), this species was more numerous in autumn- 
winter than in spring-summer. Autumn peaks in numbers 
were not pronounced in 1993 or 1994, when almost as 
many were detected in winter as in autumn. In spring- 
summer more were detected from 1200- 1559 h (x2=14.97, 
ldf, P<0.01), and more heard0800-1159 h (x2=9.94, ldf, 
P<0.001), than at other times (Fig. 7); the difference 
between autumn and winter is not significant. 
TUI (Prosthemadera novaeseelandiae). Birds first 
heard singinglcalling were not differentiated, and diurnal 
changes in numbers were not significant (Fig. 8). 
STARLING (Sturnus vulgaris). Many were detected early 
and late in the day flying fromlto roost. More were 
detected between 0600-0959 h than later in the day 
(x2=99.22, ldf, P<0.001) (Fig. 9). In spring, more were 
first heard between 1600-1959 h than earlier in the 
afternoon. In summer, most were first seen from 0600- 
0759 h, then fewer until 1600-1759h. They were most 
often first heard from 0600-0959 h. In autumn they were 
often first seen from 0600-0959 h, first singing between 
0800-1 159 h, and first calling from 0600-0759 h. In winter 
they were often first seen between 0600-0859 h, and first 
heard between 0600-0959 h. 
Wind 
Strong winds reduced the numbers of birds detected. As 
found previously (Gibb 2000), it was windiest in summer, 
slightly less so in spring, calmer in winter and calmest in 
autumn. By day there was usually least wind at dawn 
(Table 3). It gradually strengthened through the day, then 
slackened for an hour or so before dusk (Table 3). 
DISCUSSION 
Of the 9 common species selected for analysis, 8 were 
recorded unevenly through the day. Either their numbers 
or their behaviour changed, or both. 
186 Gibb 
Table 2 Percentage of songbirds detected when fist seen (S), first singing (Sg), or first calling (C); or heard (H) if song and 
calls not differentiated. 
Spring Summer Autumn Winter 
Time S Sg C S Sg C S Sg C S Sg C 
Blackbird 
0600-0759 
0800-0959 
1000-1159 
1200-1359 
1400-1559 
1600-1759 
1800-1959 
2000-2 159 
Silvereye 
0600-0759 
0800-0959 
1000-3 1-59 
1200- 1359 
1400-1559 
1600-1 759 
1800-1 959 
' h i  
0600-0759 
0800-0959 
1000-1 159 
1200-1359 
1400-1559 
1600-1759 
1800-1959 
Starling 
0600-0759 
0800-0959 
1000-1 159 
1200-1359 
1400-1559 
1600-1759 
1 800- 1959 
Table 3 Mean daily wind speed; seasons pooled. Early moming is up to 0859 h in 
autumn, 0959 h in winter. and 0759 h in spring and summer. Late afternoon is after 1700 
h in all seasons. 
Hourly records 
Period Calm Windy % calm x2 P x 2  P x2 P 
Early a.m. 70 32 68.63 ] 
131.3 <0.001 
Late a.m. 67 127 34.54 ] 1 
19.61 <0.001 
Early p.m. 39 152 20.42 1 1 
120.07 <0.001 
Late p.m. 44 52 45.83 1 
In autumn-winter, twice as many New Zealand pigeons longest and were often seen in late afternoon. Song 
were seen early in the moming than later probably because thrushes too were also detected (usually singing) early in 
some left to feed elsewhere (Gibb 2000). In spring- the morning and at dusk. In autumn-winter, more fantails 
summer (when they were present), kingfishers were often were seen in the afternoon than during the morning, 
detected at daybreak and dusk. In spring, blackbirds sang probably because flying insects were more common then 

188 Gibb 
2 
Spring 
Time (h) 
Autumn 2l 
Time (h) 
5 6 8 10 12 14 16 18 
Time (h) 
Winter 
I T  
Summer 
I/ 
5 6 8 10 12 14 16 18 
Time (h) 
Winter 
2/ 
5 6 8 10 12 14 16 18 
Time (h) 
Summer 
5 6 8 10 12 14 16 I8 
Time (h) 
Fig. 4 Number of blackbirds 
(Turdus merula) recorded 10-min 
count-I (solid bars) and 1 standard 
deviation (line bars) in spring, 
summer, autumn and winter. Times 
are: 5 = 0500-0559,6 = 0600-0759 
and at 2-h intervals to 18 = 1800- 
1959 h. 
Fig. 5 Number of song thrushes 
(Turdus philomelos) recorded 10- 
min count-' (solid bars) and 1 
standard deviation (line bars) in 
spring, summer and winter. Times 
are: 5 = 0500-0559,6 = 0600-0759 
and at 2-h intervals to 18 = 1800- 
1959h. 
Time (h) 
Dawn-dusk counts of common birds 189 
Fig. 6 Number of fantails 
(Rhipidurafuliginosa) recorded 10- 
min count-'  (solid bars) and 1 
standard deviation (line bars) in 
spring, summer, autumn and winter. 
Times are: 5 = 0500-0559,6 = 0600- 
0759 and at 2-h intervals to 18 = 
1800-1959 h. 
Fig. 7 Number of silvereyes 
(Zosterops lateralis) recorded 10- 
min count-' (solid bars) and 1 
standard deviation (line bars) in 
spring, summer, autumn and winter. 
Times are: 5 = 0500-0559,6 = 0600- 
0759 and at 2-h intervals to 18 = 
1800-1959 h. 
Spring 
./ 
5 6 8 10 12 14 16 18 
Time (h) 
Autumn 3  
Time (h) 
5 6 8 10 12 14 16 I8 
Time (h) 
- 1 Autumn I 
5 6 8 10 12 14 16 18 
Time (h) 
3 
Summer 
5 6 8 10 12 14 16 18 
Time (h) 
- Winter 
T 
5 6 8 10 12 14 16 18 
Time (h) 
5 6 8 10 12 14 16 I8 
Time (h) 
5 
Winter 
5 6 8 10 12 14 16 18 
Time (h) 
190 Gibb 
Spring 
5 6 8 10 12 14 16 18 
Time (h) 
5 6 8 10 12 14 16 18 
Time (h) 
Spring :i 
5 6 8 10 12 14 16 I8 
Time (h) 
5 6 8 10 12 14 16 18 
Time (h) 
5 6 8 10 12 14 16 18 
Time (h) 
Summer 
5 6 8 10 12 14 16 18 
Time (h) 
T Winter 1 
5 6 8 10 12 14 16 18 
Time (h) 
Fig. 8 Number of tui 
(Prosthemadera novaeseelandiae) 
recorded 10-min count-' (solid bars) 
and 1 standard deviation (line bars) 
in spring, summer, autumn and 
winter. Times are: 5 = 0500-0559,6 
= 0600-0759 and at 2-h intervals to 
18 = 1800-1959 h. 
Fig. 9 Number of European 
starlings (Sturnus vulgaris) recorded 
10-min count-' (solid bars) and 1 
standard deviation (line bars) in 
spring, summer, autumn and winter. 
Times are: 5 = 0500-0559,6 = 0600- 
0759 and at 2-h intervals to 18 = 
1800-1959 h. 
Dawn-dusk counts of common birds 191 
(pers. obs.). Fantails were seldom seen at all in summer 
when it was often windy, probably because they fed 
inconspicuously beneath the canopy. In autumn, 3 times 
as many silvereyes were detected during the morning than 
during the afternoon, perhaps because numbers were 
boosted by migrants in the morning. 
Of the 9 species recorded, 6 were liable to be either 
first seen or first heard singing or calling (Table 3). 
Blackbirds and thrushes were usually first detected in early 
morning or at dusk. Fantails were usually detected early 
in the morning in spring, late-afternoon in summer and 
autumn, and mid-afternoon in winter. Tui and silvereyes 
were detected irregularly through the day. Starlings were 
seen mainly early in the morning dispersing from their 
roosts during most of the year. 
The potential sampling bias caused by the variation in 
conspicuousness of birds detected through the day is 
obvious enough. Other questions arise however. For 
instance, why are New Zealand pigeons inactive for so 
long? Small birds forage for most of the day (Gibb 1954, 
1956); perhaps pigeons are inactive because they need to 
process food stored in the crop. Why are New Zealand 
pigeons so silent when other pigeons (e.g., wood pigeons 
(Columbapalumbus) sing so often? Perhaps they can only 
defend large territories (home ranges?) by visually 
conspicuous displays? Why are so many bird species 
voluble during the dawn chorus when "all birds sing 
together" (Grey 1927)? One might expect them to feed 
first: smaller birds can barely survive a long winter's night 
without feeding (pers. obs.). Perhaps they sing first 
because territoriality or self-advertisement is important 
and there is usually less wind early in the morning to 
distort song. 
In this connection, ornithologists often find birding 
more profitable in the morning than in the afternoon; 
perhaps this is because it is calmer in the morning. Several 
species resume singing at dusk (Grey 1927) when the 
wind slackens. The strength of the wind is clearly very 
important in determining the amount of song delivered. 
Many such questions about bird behaviour seem 
intractable. Having recognised that they exist, the first 
step is to record the facts. This is not difficult. 
ACKNOWLEDGEMENTS 
I am indebted to Dr B. Mike Fitzgerald for drawing the 
figures and for valuable discussion, and to my wife, Judy, 
for putting up with my irregular hours, for typing and for 
help in many other ways. I also thank the editor and 
referees for numerous improvements to the text. 
LITERATURE CITED 
Calquhoun, M.K. 1940. Visual and auditory conspicuousness 
in a woodland bird community: a quantitative analysis. 
Proceedings of the Zoological Society of london, series A: 
110-148. 
Dell, R.K. 1959. Some ecological aspects of the Hutt Valley as 
an animal habitat. Proceedings of the New Zealand 
Ecological S o c i e ~  8: 49-52. 
Gibb, J.A. 1954. Feeding ecology of tits, with notes on 
treecreeper and goldcrest. Ibis 96: 513-43. 
Gibb, J.A. 1955. Feeding rates of great tits. British birds 48: 
49-58. 
Gibb, J.A. 1956. Food, feeding habits and temtory of the rock 
pipit (Anthus spinoletta). Ibis 98: 506-30. 
Gibb, J.A. 1996. First seen or first heard? A useful distinction 
when counting forest birds. Notornis 43: 7-13. 
Gibb, J.A. 2000. Activity of birds in the Western Hutt hills. 
Notomis 47: 13-35. 
Grey, E., Viscount of Fallodon, K.G. 1927. The charm of birds. 
London, Hodder and Stoughton. 
Gum, L. 1954: A study of the blackbird (Turdus merula) in New 
Zealand. Ibis 96: 225-61. 
Hartley, P.H.T. 1953 An ecological study of the English titmice. 
Journal of animal ecology 22: 261-88. 
Moeed, A, Fitzgerald, B.M. 1982. Foods of insectivorous birds 
in forest of the Orongorongo Valley, Wellington, New 
Zealand. New Zealand joumal of ecology 9: 391-400. 


Dawn to dusk counts of common or garden birds, Wellington, New Zealand

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Dawn to dusk counts of common or garden birds, Wellington, New Zealand

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