USE OF NEST BOXES BY GOLDENEYES IN EASTERN NORTH AMERICA

2007·4.8 MB·English

by  Jean-Pierre L Savard

The Wilson Journal ofOrnithology 119(1):28—34, 2007
USE OF NEST BOXES BY GOLDENEYES IN
EASTERN NORTH AMERICA
JEAN-PIERRE L. SAVARD> AND MICHEL ROBERT' ^
—
ABSTRACT. We evaluated and monitored use of 105-133 nest boxes by Common Goldeneye (Bucephala
clangula) and Barrow’s Goldeneye {Bucephala islandica) during 1999-2004 on 60 lakes ofhigh plateaus ofthe
Laurentian Highlands, in the boreal forest of Quebec, Canada. Only three species of birds used nest boxes
regularly, American Kestrel (Falco sparx’erius), Barrow’s Goldeneye, and Common Goldeneye. The proportion
ofnest boxes used by goldeneyes in 2000-2004 ranged from 23 to 43% whereas hatching success ranged from
37 to 67%. Successful Barrow’s and Common goldeneye clutches averaged 6.76 ± 0.38 (SE, n = 29) and 1.11
± 0.44 eggs in = 31), respectively. Predation in nest boxes was not a major mortality factor. Goldeneyes used
all nest boxes independent of their location but reproductive success was lower in nest boxes 25-160 m from
shore in clearcuts. The numberofBarrow’s and Common goldeneye breeding pairs increasedbetween 1999 and
2003, but number of broods remained stable after an increase in 2000. Received 15 December 2005. Accepted
12 August 2006.
The eastern population of Barrow’s Gold- reducing the impact of logging on Common
eneye {Bucephala islandica) is estimated at Goldeneyes {Bucephala clangula) in Scandi-
—1,400 pairs (Robert et al. 2000a) and was navia (Cramp and Simmons 1977). Nest-box
classified as Special Concern by the Commit- programs have proven successful overall for
tee on the Status of Endangered Wildlife in most cavity-nesting ducks (Zicus 1990, Hepp
Canada in November 2000 (COSEWIC 2006). and Bellrose 1995, Eadie et al. 1995), but po-
Its breeding range has been discovered only tential problems could reduce their efficiency.
recently in the Quebec Laurentian Highlands, These include increased predation rates, nest
on the north shore of the St. Lawrence River parasitism, and increased competition for ad-
estuary and gulf (Robert et al. 2()()0b). It equate brood-rearing ponds (Andersson and
breeds on small lakes, often without fish at Eriksson 1982, Savard 1988, Eadie et al.
>500 m in elevation (Robert et al. 2()()()b), 1995, Evans et al. 2002, Poysa and Poysa
where tree growth is slow and large trees with 2()()2). Nest boxes in British Columbia had
suitable nest cavities are apparently rare (MR, larger clutch sizes, lower nesting success, and
pers. obs.). Eorests in its breeding area are un- a different suite ofpredators than natural nests
der intense logging pressures (Robert et al. (Evans et al. 2002). There is also the under-
2()()()a) and availability of suitable nesting lying risk that nest-boxes may attract preda-
cavities is an issue of concern. tors and become ecological traps (Battin
Nest boxes have been used successfully to 2004). A related concern is inter-specific com-
locally increase the abundance of cavity-nest- petition between Barrow’s and Common gold-
ing waterfowl (McLaughlin and Grice 1952, eneyes, which use similar nest sites and ex-
Johnson 1967, Nichols and Johnson 1990) and clude each other from pair and brood territo-
to establish new populations (Doty and Kruse ries (Savard 1982, 1984), and are known to
1972, Eriksson 1982, Dennis and Dow 1984). occasionally hybridize (Martin and Di Labio
Barrow’s Goldeneyes have readily used nest 1994).
boxes in British Columbia (Savard 1985, We examined use ofnest boxes by Barrow’s
1988) and their use has increased the number Goldeneyes in their high elevation breeding
of broods locally. The small Icelandic popu- habitat. Specifically we; 1) evaluated use of
lation uses nest boxes as well (JPS and MR, nest boxes by goldeneyes and other wildlife
pers. obs.). Nest boxes have been useful in in the only known Barrow’s Goldeneye habitat
accessible by road, 2) measured goldeneye re-
productive success in nest boxes, 3) compared
Q1C14.'1CGaRnIoaVudtie4aHnd5e,WiIlC'daElngilafidseae.,SePr.vOic.e,BoExnv1i0r1o0n0m,enStainCtaen-aEdoay.. 4n)esct-obmopxaruesde tihnerreellaattiiovnetaobbuonxdanlocceatoifon,Coamn-d
-Corresponding author; mon and Barrow’s goldeneye pairs and
e-mail: [email protected] broods.
28
Savard and Robert • NEST BOX USE BY GOl.DENEYES 29
FIG. 1. Goldeneye nestbox study area(ZECChauvin) in the Laurentian Highlands northofthe St. Lawrence
River estuary, in the boreal forest of Quebec, Canada.
METHODS range = 25-160; mean height above ground
Study Area.—The study was conducted in = 4.0 m, range = 3.3-5.3). We also installed
the Zone d’exploitation controlee (ZEC) 25 single nest boxes in September 1999 on a
Chauvin, a 610-km2 area —40 km northeast of tree or snag in clearcuts near additional lakes.
Tadoussac (48°09'N, 69°43'W), Quebec, All nest boxes were highly visible, measured
Canada (Eig. 1). ZEC Chauvin is on high pla- 24 X 22 X 60 cm, and had an entrance hole
teaus of the Laurentian Highlands, north of measuring 10 X 13 cm. Nest boxes were
the St. Lawrence River estuary, in the balsam checked between 1999 and 2004, at least
fir {Abies baIsamea)-whitQ birch (Betula pa- twice in 1999 (once in mid incubation and
pyrifera) bioclimatic domain ofthe boreal for- once after hatching) and usually at least three
est. Mean annual temperature and precipita- times in 2000-2004, with a first visit at the
tion are 0.0° C and 1,300 mm (35% as snow), end of egg-laying. Occupied boxes were
respectively (Robitaille and Saucier 1998). checked more often (i.e., 4-6 times) to better
Common and Barrow’s goldeneye pairs and estimate clutch size and capture females. Six-
broods use the lakes of this area (Robert et al. teen Barrow’s Goldeneye females were cap-
2000a), which is under intense forest exploi- tured in nest boxes and fitted with backpack
tation and is managed for hunting, fishing, and radio-transmitters in 2001-2003 to study
other recreational activities. brood ecology. None was recaptured or seen
—
Nest Boxes. We installed 1 1 1 nest boxes again on the study area in 2002-2004 (Robert
in August-September 1998 at 37 lakes in the et al. 2006). —
study area, three per lake: one above water on Pair and Brood Counts. We conducted
a steel post (mean distance from shore = 6.6 Barrow’s and Common goldeneye pair and
m, range = 3-18; mean height above water brood surveys in a 217-km2 area of ZEC
1.4 m, range = 0.08-2.2), one on a tree at the Chauvin encompassing all lakes with three
edge of the lake (mean distance from water nest boxes, as well as 19 of 25 lakes with
edge = 4.1 m, range = 0.8-12.7; mean height single boxes. This area includes 239 lakes
above ground = 4.0 m, range = 3.4-4.5), and (mean = 5.4 ha, SD = 11.3, range = 0.01-
one on a tree or snag in a recent clearcut 115), of which 132 are <2 ha. We surveyed
(mean distance from water edge = 74.6 m. goldeneye pairs on 60 lakes of this area each
1
30 THE WILSON JOURNAL OL ORNITHOLOGY • Vol. 119, No. 1, March 2007
TABLE 1. Number of goldeneye nest boxes used“; boxes were installed in fall 1998 (n = 111) and 1999
(/? = 25) in the boreal forest ofQuebec, Canada.
1999 2()()() 2001 2002 2003 2004
Barrow’s/Common goldeneyes 30 35 56 54 36
1
American KestreP 12 22 (1)‘-' 27 ( Y 27 (3)^- 8 (1)‘^ 2
Hooded Merganser*" 0 0 0 2 (3)^^ 0 (3)‘^ 2
Tree Swallow {Tachycineta hicolor) 3 2 0 0 0 0
Northern Llicker (Colaptes auratiis) 1 1 1 0 1 0
Red SquirreP 0 1 8 (11*-- 4 8 (7)^- 3 (1)'^
Boxes available 105 133 127 130 133 128
Boxes used 17 56 71 89 71 43
Percent used 16 42 56 69 53 34
“Atleastoneeggwasfoundorinthecaseofsquirrels,anest.
Somenestboxeswereusedby morethanonespeciesduringagivenyear.
Thenumberinparenthesisrepresentsspeciesindoubleoccupancy.
year between 21 May and 28 June 1999- RESULTS
2003. We surveyed most (75%) lakes only —
Nest Boxes Between 105 and 133 boxes
once in 1999 (late May), and most (>75%) at were available. yearly (1999—2004), and were
least twice in subsequent years (late May and used by six species of birds (Table 1). The
in early to mid-Jun). All goldeneyes were re- proportion of boxes used increased from 16%
corded as pair, lone adult male, lone adult fe- in 1999 to 69% in 2002, and decreased to 34%
male, groups of adult males and/or females, in 2004. Barrow’s and Common goldeneyes
ayenadri[mSmY]atiunrdeivifdeumaalsl)e. oWremuasleed t(hi.ee.m,asxeicomnudm- were the major users in all years but 1999
followed by American Kestrels (Falco spar-
number ofadult males seen on each particular
tloakdeeriinvea gaivmeenasyueraerosfupmamierdabaucnrdoassncaellilnaktehes (v/ezri=iis)1.2)Keasntdreltsheidromuisenapteeadkebdoxinus2e00i1n (1zz99=9
bsrtouoddysaorneat.heWseameallsaokess.urSuvrevyeeydefgfoolrtdsenweeyree c2r7e)asainndg 2in002200(3zz (z=z= =27)8)baefnodre20a0b4ru(pztzly= d2e)-.
less intensive in 1999 when 27% of the lakes Hooded Mergansers {Lophodytes cucuUatus)
were surveyed once and 46% twice during the used boxes in 2002 and 2004 (two nests each
btoro2o0d03s,eamsoosnt(l2a0keJsun(7t7o%)1 1weSrepe).suFrrvoeymed2()>()3() oyenaer).speScoiemseinbotxheesswaemreeyeuasre.dSbiyx cmaosrees etahcahn
times. We used head shape and color, bill involved goldeneyes and American Kestrels,
shape, and wing pattern to separate Common and goldeneyes and Hooded Mergansers.
and Barrow’s goldeneye females (Tobish Eight involved goldeneyes nesting on unoc-
1986). Adult and immature females were sep- cupied red squirrel {Tamiasciurus Imdsonicus)
arated by iris color (Tobish 1986). We com- nests, of which .seven successfully hatched.
bined the number of immature females iden- There was one instance of an American Kes-
tihed with the number of females of undeter- trel nesting on a red squirrel nest.
mined age (there were few and most were Both Common and Barrow’s goldeneyes
likely immatures), as an estimate of immature used nest boxes (Table 2), although the rela-
abundance in the study area. tive use by each species could not be ascer-
—
Statistics. Means ± SE are presented. We tained because of the large proportion ofbox-
used analysis of variance to compare means. es where species of goldeneye could not be
Differences in frequency were tested using X“ identihed. Only one box was used by gold-
and Pearson’s standardized residuals (Agresti eneyes in 1999. Box use increased to 30 in
2002). All nest boxes were used to estimate 2000, peaked at 56 and 54 in 2002 and 2003
the overall use of nest boxes by wildlife, but respectively, and decreased to 36 in 2004.
analysis of nest-box use in relation to location Goldeneye hatching success (>1 egg hatch-
was limited to lakes with properly located tri- ing) ranged between 37 and 67% (Table 3).
os of boxes (/z = 29-35 lakes). Eighty-hve of 110 nest failures (no egg hatch-
Savanl and Robert • NEST BOX USE BY GOI.DENEYES 31
TABLE 2. Number of nest boxes used by Barrow’s and Common goldeneyes; boxes were installed in fall
1998 (/? = III) and 1999 {n = 25) in the boreal forest of Quebec, Canada.
1999 2()0() 2001 2002 2003 2004 Totals^
Number of boxes 105 133 127 130 133 128 651
Barrow’s Goldeneye 0 9 7 12 1 1 4 43
Common Goldeneye 0 9 10 19 9 6 53
Goldeneye sp. 1 12 18 25 34 26 1 15
All goldeneyes 1 30 35 56 54 36 212
Used by goldeneyes (%) 1 23 28 43 41 28 33
“Excludes 1999.
ing) were associated with partial or complete in the next 2 years (2003 = 7.31 ± 0.71, n =
egg loss, 15 with no egg loss, and 10 for 16; 2004 = 6.78 ± 0.92, n = 9). These chang-
which egg loss could not be ascertained. Only es are not significant {F = 1.23, P = 0.30).
28 nests had obvious signs of predation (i.e., Successful Barrow’s Goldeneye clutches were
broken eggshells or presence ofdry yolk) and smaller (6.76 ± 0.38, n = 29) than those of
at least 10 females successfully hatched eggs Common Goldeneyes (7.77 ± 0.44, n = 31;
in spite of partial egg loss (1-5) during in- F = 3.0, P = 0.088). The same difference was
cubation. There were no signs of predation or observed for unsuccessful clutches (6.62 ±
broken eggs in all cases. More nest failures 0.36, n = 37 vs. 7.52 ± 0.35, n = 46; F =
occurred after incubation had started (57%, ti 3.17, P = 0.079).
= 107 nests). Goldeneyes used all boxes independently of
Four clutches had >12 eggs (13-15). All their location (above water, along shoreline or
boxes with <3 eggs were unsuccessful, but >25 m from shore) in all years (Table 4; x^
five of eight 3-egg clutches and two of six 4- = 5.50, P = 0.70, df = 8). Goldeneyes using
egg clutches were successful. A similar pro- nest boxes in clearcuts were slightly less suc-
portion of <6-egg (32.7%, n = 49) and >9- cessful (40%, n — 86) than those using boxes
egg (36.4%, n = 22) clutches hatched suc- along the shoreline (56%, n = 63) or above
cCee=elggsugg7stss0fc)u(h(lxxehl^^syat=-oc(fhx6^i.166n3-,.g=97P,seu0P=gc.gc00es<9.s30s,h01a,.tdP0hd0afa1n-,=gcrdle0fu1a.)t.t7=ce6Thr,eh1s(e)d6wfa7aiv.nt=e1dhr%a,><1g)96ne. cfws=ehiasortsrm2efe)eru.ldli(nPtt5eehh0aaa%trn=;sboononth’x1es.=er7s1ss5;ti6(n,aainbncxdol'avercea=dlriewcza4auer.ttdc5seur1twr,se=ePsri0e=d=.u4la5e0l—;s.s2s1a.lc10s,oo0u)nncd.-g-f
clutch size of successful goldeneyes increased
American Kestrels clearly preferred nest box-
degugrsi,ngnth=e f1i8r;st2300y1ear=s 7(.280500±=0.73.7,22n±=0.1535; es away from water, having used 54 boxes/
2002 = 8.13 ± 0.68, n = 15) and decreased (1391%)(a2t8t%h)e oitnhecrletawrocutlsocavteirosnuss(xo^nl=y 6130./3,38P2
< 0.001, df = 1). —
esTinAsBtaLllEed3.in fNalelst19s9uc8ce(nss=of1g1o1l)deannedye1s99i9n n{enst=bo2x5-) ly PtahirreeantidmeBsromoodreCouBnatrrso.w’TshetrheanweCroemnmeoarn-
in the boreal forest ofQuebec, Canada. goldeneye males on the study area in 1999
(Table 5). Barrow’s and Common goldeneyes
Nestfate had increased from 28 to 43 and from 10 to
Year Nests Hatched^(%) Failed(%) Unknown(%) 46 estimated pairs, respectively, in 2003. The
1999 1 0 100 0 number of immature (SY) females varied be-
2000 30 67 27 7 tween years. The contrast in numbers for both
2001 35 40 57 <1
species combined was especially great be-
2002 56 37 61 <1
2003 54 41 56 <1 tween 2000 {n = 9) and 2001 (/? = 74). This
2004 36 53 47 0 greater number of immatures in 2001 was fol-
Totals 212 45 52 <1 lowed by a marked increase in the number of
“Atleastoneegghatching. pairs of both species in 2002. A peak in the
1
32 THE WILSON JOURNAL OL ORNITHOLOGY • Vol. 119, No. I, March 2007
TABLE 4. Location ofnest boxes used by goldeneyes; nest boxes were installed in fall 1998 {n = 111) and
1999 (// = 25) in the boreal forest of Quebec, Canada.
Occupied(%)
Year Nests(Lakes)“ Noccupied Abovewater Shoreline Inclearcut
1999 93 (31) 1 1 0 0
2000 102 (34) 30 27 47 27
2001 87 (29) 27 33 33 33
2002 93 (31) 43 37 37 26
2003 105 (35) 44 27 36 36
2004 93 (31) 20 45 20 35
“Threenestboxesperlake(oneabovewater,onealongtheshoreline,andone >25 mfromshore).
number of immatures occurred in 2002, fol- The preference of kestrels for nest boxes in
lowed by an increase in the number of Com- clearcuts may be related to the more central-
mon Goldeneye pairs in 2003. This increase ized position of these boxes within the terri-
in pairs did not yield a proportional increase tory which likely allows adults to better pro-
in the number ofbroods ofeither species. The tect the nest.
brood/pair ratio doubled between 1999 and The large increase in nest box use in 2002
2000 and decreased in following years (Table corresponds to the time females hatched in
5). 2000 would have initiated first breeding. The
decrease in 2003 and especially 2004 may be
DISCUSSION
due to the suspected over winter mortality of
This study is the first to examine use ofnest .several successfully reproducing adult Bar-
boxes by Barrow’s Goldeneye in eastern row’s Goldeneye females (Robert et al. 2006).
North America. Goldeneyes were the main us- Goldeneye hatching success was similar to
ers of nest boxes in the study area, conhrming that reported elsewhere (Savard 1988, Evans
their usefulness as a potential management et al. 2002). Nest desertion was the major
tool in the boreal forest of the Laurentian cause of failure similar to other studies (Gren-
Highlands. The only other important user of quist 1963, Rajala and Ormio 1970, Eadie et
nest boxes in the study area was the American al. 2()00). We suspect that competition for nest
Kestrel. Nest boxes allowed this species to ex- sites (Erskine 1960, 1990; Lumsden and
ploit temporary new open habitats created by Wenting 1976), a large number of first year
logging, whereas vegetation regrowth may breeders (Grenquist 1963), and disturbances
have contributed to their low use in 2003 and related to fishing may have contributed to the
2004. Rohrbaugh and Yahner (1997) found high level ofnest desertion. Eadie et al. (1995,
that boxes frequently used by American Kes- 2()()0) indicated that true clutch size of a sin-
trels were associated with extremely open gle female goldeneye is probably 6-9 eggs.
habitat dominated by herbaceous vegetation. Hatching success ofclutches in that range was
TABLE 5. Abundance of Common and Barrow's goldeneyes on 60 lakes of ZEC Chauvin, in the boreal
forest of Quebec, Canada.
Barrow'sGoldeneye CommonGoldeneye
Year Pairs“ Broods Brood/pair SYF Pairs“ Broods Brood/pair SYF
1999h 28 10 0.36 12 10 4 0.40 1
2()()() 24 17 0.71 6 13 1 1 0.85 3
2001 33 17 0.52 49 13 9 0.69 25
2002 42 15 0.36 70 28 1 0.39 67
2003 43 14 0.33 44 46 7 0.15 49
“Pairs + unpairedmales.
^Number of SY females unreliable for 1999 because only one survey (late May-early Jun) ofmost 05%) lakes; the numberofbroods is likely
underestimatedin I9‘)9.
Savanl and Robert • NEST BOX USE BY CJOl.DENEYES 33
higher in our study than in smaller and larger ident for Common Goldeneyes, especially in
clutches. Large clutches are likely caused by 2003 when the brood/pair ratio was only 15%.
nest parasitism, which is frequent in golden- Poysii and Pdysii (2002) showed that provi-
eyes, and often results in nest desertion (Er- sion of nest boxes for Common Goldeneyes
iksson and Anderson 1982, Eadie and Fryxell did not always result in greater productivity
1992). Smaller clutches are often the result of because of density dependence factors during
first year breeders which are more prone to nesting and brood-rearing. We believe that
desertion (Eadie et al. 2000). Our smallest in- nest boxes could be used as a recovery tool
cubated clutch was three eggs {n = 8, 5 hatch- for the eastern population of Barrow’s Gold-
ing); the previously reported smallest one was eneyes in areas where intensive forest exploi-
four eggs (Eadie et al. 1995, 2000). tation may limit natural nest sites. However,
Goldeneyes used nest boxes independently their potential for increasing productivity may
of their location. The tendency offewer gold- be limited by the availability of local brood
eneyes using clearcut boxes from 2000 to rearing habitats.
2002 may be related to the preference of kes-
trels for boxes in clearcuts. Goldeneyes used ACKNOWLEDGMENTS
nest boxes at all three locations similarly in
2003-2004 when kestrel use of boxes was This study was funded by the Species at Risk Di-
vision of the Canadian Wildlife Service, Quebec Re-
low. Poysa et al. (1999) reported a preference gion; thanks to Isabelle Ringuet. We thank all field
by Common Goldeneyes for nest boxes close personnel fortheirassistanceespeciallyChristian Mar-
to the water over those in forests (46-190 m cotte and Laurent Dufour, who conducted most sur-
from shore). They did not find any differences veys and nest box monitoring, and Paul Messier, He-
in predation rates between the two locations lene Senechal, Rejean Benoit. Dominique Bourget,
(Poysa et al. 1997). Our boxes may have been JDeeamne-rFsr,angOoliisvieRrouMsastehaiue,u,Yaannnd KForlabnecionisssoSnh,affRearp.haWeel
more conspicuous than those in Poysa et al.’s thank Jacques Leclerc for statistical advice, Michel
(1997, 1999) study, as they were highly visi- Melan^on andJean-Fran^ois Rail forproducing Figure
ble in clearcuts. Unlike in British Columbia 1, and Boisaco Inc. for logistic support. We thank J.
(Savard 1988, Evans et al. 2002), black bears T Ratti, M. C. Zicus, and an anonymous reviewer for
{Ursiis americcmus) were not important pred- helpful suggestions.
ators, with only one box destroyed over the
LITERATURE CITED
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