日本産野鳥8例の飼育実験による色選好性試験
誌名
誌名 Animal behaviour and management ISSN
ISSN 18802133
著者 著者
上野, 安貴 東野, 晃典 高橋, 麻耶 近江谷, 知子 鈴木, 友 鈴木, 馨 巻/号
巻/号 49巻4号
掲載ページ
掲載ページ p. 164-170 発行年月
発行年月 2013年12月
農林水産省 農林水産技術会議事務局筑波産学連携支援センター
Tsukuba Business-Academia Cooperation Support Center, Agriculture, Forestry and Fisheries Research Council Secretariat
‑ Short Reportー
Ana 世 . e m p tt o i n v e s t i g a t e color preference using e i g h t cases o f c a p t i v e Japanese w i l d b i r d s
Aki UEN01， AkinoriAZUMAN02， Maya TAKAHASHe， Tomoko OMIYA4， Yu SUZUKI5， Kaoru SUZUKI1* lField Science Cen
賦
TokyoUniver町
ofAgriculture and Technology， Fu伽
183・8509，Japan;mkohmaZoologdG紅densof
何
Yok恥
ohama，4FKa佃na但z側awaZoological Gardens of
Y c 白
okohama，孔Yokohama 236ふ ω‑ 心
O∞
04位2，Japan 5NogeYama Zoological Gardens ofYokohama，Yokohama 220・0032，JapanYumernigasaki Zoological Park ofKawasaki， Kawasaki 212・0055，Japan
*Corresponding au
血
or.E‑mail address:[email protected]t .
acj .
pA b s t r a c t
Bird repellent devices have been used extensively to induce wild bird pests to avoid otherwise at回c1:1veor palatable materials. Although color has long been considered a potential visual repellent among birds， which colors
釘ecommonly unattractive to wild bird species in Japan has not yet been elucidated. We have obtained eight cases of captive Japanese wild birds to investigate their color preference， resulting in a consistent color preference among
也
em.百leb仕dsused in也
ep.resent a伽 mptconsisted of an individual each of eight species: tree sparrow (Passer montanus)， rufous turtle dove (Streptopelia orientalis)， bamboo par出dge(Bam伽
icolathoracica)， brown‑eared bulbul (Hyps伊etes amαurotis)， crested m:戸a (Acridotheres crist，αtellus)， dusky thrush( 払r
d;附 naumαnni)， azure‑winged magpie (Cyanopicaの ほn
a)，and black kite (Milvus migrans). The birds were presented wi也
four feeders血
athad lids colored red， yellow， green and blue. None ofthe birds selected yellow or blue as也
eirvery first choice. In a
ddition， preference scores differed between the four colors. All birds showed the less preference for yellow， and also blue was less preferred by most of the birds. In contrast， most birds preferred red and green. Thus，也
erewas a significant difference between也
escores of yellow and green. The findings of也
epresent evaluation suggest that yellow is better suited for con仕ollingbirds and also blue would be a good color， but也
atred and green are not so suitable for visual repellents. To increase the e伍
cacyof colors for deterring birds， further investigation would be desirable to combine the initial deterrence of也
evisual repellents with other aversive stimuli， such as chemosensory repellents or企
ighteningagents.Key words : wild birds， visual repellent， color preference， case study， yellow
Animal Behaviour and Management， 49 (4): 164‑170， 2013 (Received 30 July 2013; Accepted for publication 20 Norvember 2013)
Introduction
The activities of wild birds often conflict with those of humans. Birds have caused extensive damage to agricultural produce in rural areas， and become a public nuisance in urban areas (De Grazio 1978; Fitzwater 1988; Messmer 2000; Bruggers et al. 2002; Fall
&
Jackson 2002). For example，just under 30% of damage to agricultural production in Japan by wildlife is caused by b
凶
s (Minis句 of Agriculture， Fores町
T and Fisheries 2010; Minis位yof Agric叫町民， Fores町
r姐 d Fisheries 2011).I n
addition， their tendencies to defecate in public areas， sca伽rgarbage and sometimes get close to humans without any fear not only make them a public nuisance， but also can adversely e能 ct human health and safety in urban areas (De Gr抵101978; Bruggers et al. 2002; Karasawa 2011).
Repellent substances and devices cause pest species
to avoid otherwise at佐activeor palatable materials. Birds are ex佐emelyvisual animals， and as our former study has already demonstrated， they have a well developed capacity for visual learning (G
出
2006; Ueno&
Suzuki 2014). Consequently， visual cues， such as aposematic coloration， can act as potential repellents and也
eycan facilitate learning to avoid secondary repellents. For instance， in a study on house sp紅rows， blue‑coated bait items were consumed signific祖 tly less企
equently白
anuncoated bait items (Pawlina&
Proulx 1996; Clapperton et al. 2011).
I n
addition， chernical repellents inducing taste aversion or gas位ointestinal malaise were more e妊ective when combined with colored bait or flags (Mason&
Reidinger 1983; Avery & Mason 1997; Wemer etα1. 2008; Clapperton et al. 2011). Color cues
也巴
refore seem to be very impo此 姐tprimary repellents for sc紅泊gbird pests. Nonetheless， the colors with theUENO，
Az
UMANO， TAKAHASHI， OMIYA， SUZUKl AND SUZUKIgreatest potential for repelling bo
出
known and potential pest bird species have yet to be clarified in Japan.We have obtained eight cases of captive Japanese wild birds， i.e.仕eesp卸 ow(Passer montanus)， rufous turtle dove (Streptopelia orientalis)， bamboo par出dge (Bambusicola thoracica)， brown‑eared b
叫
b叫
(Hypsijヮ
etesamaurotis)， crested myna (Acridotheres crisωtellus)， dusky thrush (Turd;凶 naumanni)， azure‑winged magpie (CyanopiDαcyana)， and black kite (Milvus migrans)， in order to investigate也 町
color preference， resulting in a consistent color preference among也
em.百
le present case study is也
e first reported attempt to evaluate the Japanese wild birds' color preference.All of the species tested in
也
epresent investigation m勿
pically associated with human habitati'On， irnplying也
at也
eyc'Ould easily affect human activities， partic叫
arly the sp紅T'OW S，
d'Oves，
b叫
b叫
s and azure‑winged magpies， which c阻 all damage agricultural crops (Eguchi et al 2002). Cr回tedmynas， which 'Often construct their nests 'On buildings， 釘ean ex'Otic species也
at is spreading rapidly in Japan (Eguchi& Am
an'O 2004).Materials and Methods Animals and housing
The present experirnent examined c'Ol'Or preference
m
組 individual'Of each 'Of the品
ll'Owingeight bird specles: 住 民 sparrow，
ruf'Ous turtle d'Ove，
bamb'O'Opartridge， brown‑eared bulbul， crested myna， dus匂r
thrush， azure‑winged magpie， and black kite. The birds tested c'Onsisted of rescued birds
也
atwere仕 組S島町ed企omthe Yok'Ohama Z'Ool'Ogical Gardens 'Of Y'Ok'Ohama， Kanazawa Z'Ool'Ogical Gardens 'Of Y'Ok'Ohama， N'Ogeyama Zool'Ogical Gardens 'Of Y'Ok'Ohama and Yumemigasaki Z'O'Ol'Ogical Park of Kawasaki， t'O也巴
T'Okyo University of Agriculture and Techn'Ol'Ogy Field Science Center f'Or scientific research. Alth'Ough all 'Of the birds had previ'Ously been physically injured
，也出
c'Onditi'On was stable and也eirinjuries did n'Ot interfere with daily activities such as feeding 'Or m'Oving ab'Out in cages. Birds were housed individually in experirnental cages made 'Ofw'O'Od (dirnensions: W60xH90xD90 cm f'Or the azure‑winged magpie， 105x125x95 cm for
也
e black kite， 組d30x45x90 cm for the 'Other birds). F'O'Od was pr'Ovided ad libitum after the daily tests which started at 8.00， but rem'Oved at 17.00. Water was pr'Ovided ad libitum. The birds were maintained in a c'Onstant envir'Onment room at a temperature of 240C and under a phot'Operiod of 10Ll14D. During the exp巴rirnents， experirnental cages were evenly illU 1 1 1 I l l
ated by neu仕alwhite florescent lights.The present study was c'Onducted 'On the required registrati'On f'Or keeping wildlife and permission
f r
'Om the Toky'O University of Agri叫
ture姐 dTechn'Ol'Ogy Laborat'Ory Animal Care and Use C'Ommittee.Experimental procedure
The experirnent c'Onsisted of 5‑day acclirnatizati'On period f'Oll'Owed by a 5‑day c'Olor preference tes
t .
In血e acclirnatizati'On peri'Od， birds were habituated t'O the experirnental appara旬sand the pr'Ocedures empl'Oyed f'Or the col'Or preference test .
A丘er也isacclimatizati'On peri'Od， the reactions t'O c'Ol'Or cues were tested using f'Our c'Ol'Ors in a col'Or preference test.Experimental stimuli
The c'Ol'Or preference test c'Onsisted 'Of presenting the birds with cues in也eform 'Of col'Ored feeder lids (diameters: 4.2 cm for
批
treesp釦 ' OW，7.7 cm f'Or the black kite， and 6.2 cm f'Or the 'Other birds)， which meant birds had t'O insert their beaks企'Om也e'Open p紅t'Of c'Ol'Ored lid t'O get fo'Od in the feeder. Feeders were supp'Orted by feeder holders， which were arranged in a grid c'Onsisting 'Oftw
'O r'Ows組 dtw
'O columns in由
e experirnental cage (Fig. 1).As the lid col'Ors standardized f'Oll'Owing the Cyan Magenta Yell'Ow Key plate c'Ol'Or m'Odel， red (0.77.68. 13:C.M.YK)， yell'Ow (0.13.100.4)， green (100.0.44.40) and blue (100.35.0.33)， were presented. Experirnental f'O'Od in each feeder was a mealw'Orm f'Or the仕 切sparr'Ow，pige'On feed for the ruf'Ous伽rtledove， f'Owl feed for the bamboo p
紅 白
dge，a pellet of c'Ommercial m戸
afood f'Or the br'Own‑eared bulbul and crested m戸la，a pellet 'Of c'Ommercial d'Og f'Ood f'Or the dusky也
rushand azure‑winged magpie， and a slice 'Of chicken liver f'Or the black kite.AcclimαtizαtionPeriod
Over three successive days of也eacclirnatizati'On peri'Od， birds acquired the skills necessary f'Or per
白
rmmg也.etest， i.e. inserting the beak int'O the feeder企'Om也e'Open part 'Of也elid t'O 'Obtain f'Ood; feeders with white lids were used f'Or白
isstage 'Of the experirnent. On the first day 'Of仕aining，birds were位 創nedt'O eat
企
om血
efeeders with open lids. On the sec'Ond佃d由
e也
irddays， the lids were partially cl'Osed， which meant血
atthe birds c'Ould see也efo'Od but也ey had t'O insert their beaks into the feeder企omthe 'Open part 'Of lid to 'Obtain f'Ood. F'Our feeders were presented'On a 2 x 2 grid f'Or every trial， and training sessi'Ons lasted 30 minutes each day. Feeders were replaced and the next trial was started when birds emptied all four feeders 'Or when n'O m'Ore selecti'Ons were made for 15 minutes. These proced町 田 madeit certain也atbirds had n'O preference f'Or the positi'On 'Of feeders.
Color Pr，
φ
rence TestIn the c'Olor preference test， f'Our col'Ors， red， yell'Ow， green and blue were presented on the lids 'Of four feeders (Fig. 1). The lids were p制 iallycl'Osed， as they were on the sec'Ond and tl
町
ddays 'Of住ainingin血
e acclirnatizati'On peri'Od， which meant that birds c'Ould see也ef'O'Od but也eyhad to insert their beaks int'O the feeder企'Omthe 'Open part 'Of the lid. Once the birds had emptied all f'Oぽ ofthe feeders， 'Or if no furtherCOLOR PREFERENCE lN JAPANESE Wll.D BIRDS
Experimental cage
. . . ‑ ‑ ‑ ‑ . . . ̲
→、、、 ，
、 ーーーーーー'
~ノノ
Feeder holder
¥ 〆
イ
Feeders used in the expel'imentRed 】
配e
llow)氏
Green)氏Bl
ue')菅、』、、 ..，.官、』、、 ~曹、』、・.JJ I
Feeder lid can open wide w hen birds insert theil、beaks
Fig.1 Diagrammatic representation of experimental apparatus (top view).
selections were mad巴for15 minutes， then feeders were randornly replaced with new feeders containing food and
出
enext trial was struted. ln every trial，巴achcolor was assigned a score based on出巴
ord巴
rin which it was selected; fOI・exampl巴，the first color to be selected was assigned a score of 1， the second a score of 2，組dso on. If a feeder of a certain color was not selected by the end of a trial， then a score of 5 was assigned to the color in白
attria. lIn this way， the least‑chosen colors were assigned th巴highestscores. If no colors were selected in a certain trial， that trial was excluded from出
eanalyses. The color preference test was conducted over five days， with 30 minutes of direct observation on any given dayData analysis
The number of trials made by birds in the whole preference test were as fo11ows: 6 trials by the tree sp釦 ow，5 by出erufous twtle dove， 11 by the bamboo paItridge and brown‑eared bulb叫，31 by血ecrested myna， 10 by th巴 dus
勾
thrush and azure‑winged magpie， and 4 by the black kite. To assess the presence of consistent color preference among the tested birds， the very frrst choic巴 inthe白sttrial and也emean scores assigned to each color of a11 trials in each bird wer巴used.In addition， mean preference scores of each color， calculated from the scores in each bird， were compared. To detect a si伊lificant difference， a Friedman test (Pく 0.05)was used. Then， Wilcoxon signed rank tests (P < 0.05) fo11ow巴dby Bonferroni corrections were undergone for multiple comparisonsThese statistical analyses were conducted using
出
e statistical package R.Results
Al
l of the birds in the color preference test selected either red or green as出
eirvery f11"st choice (Fig.2); none of the birds selected ye110w or blue the very f11"st tirne. Thus， a11 of出巴
birdsgave high scores to ye11ow， and most of出巴
birdsalso gave a high score to blue (Fig.2).Friedman test revealed
也
atthe pr巴ferencescores assigned by birds differed significantly among fOill colors (%2 = 11.0， P = 0.01). Wilcoxon signed rank tests fo11owed by Bonferroni cOITections revealed that the scores assigned to ye110w were significantly higher than出巴
scoresassigned to green. Blue and red were assigned也巴 intermediatescores between ye110w and green， but blue was given relatively high scores compared to red (Fig.3). These would have been caused by the result that most birds more or less prefi巴町edred and green to ye110w and blue， with some exceptional prefer巴nces也atthe tree sp釦 owand dusky thrush showed a strong prefi巴rencefor green組 dblu巴 compru'ed to red and ye110w (Fig. 2)As a result in出epresent sωdy， ye110w was the only color that was assigned high scores by a11 of the bird species tested: ye110w was always given scor巴sof over 3， i.e. the nliddle of 1・5points (Fig. 2)， wh抑 制blue revealed a relatively high score (Fig. 3)
UENO， AzUMANO， TAKAHASHI， UMIYA， SUZUKl AND SUZUKI
ζ J A
斗弓3
ウ 血 宅 i A U
ω H 8 2 5 2
ロ Red
図
Yellow
ロ Green 口 Blue
Fig. 2 Mean preference score assigned to feeder colors (:tSE) and tthe ve叩firstchoice selected by each bird
4 3.5
a̲b ω 3
0 υ
rn
i e
2.5Q)
旬輔・4
よ 2
1.
5
b
a̲b
a
Red Yellow Greell Blue
Fig. 3 Mean preference scores of each feeder color (:tSE)， calculated from the scores of each bird. Different letters indicate significant difference (P
< 0.0083 after Bonferroni corrections)
Discussion
Wild birds can cause serious damage to agricultural production and can disrupt human activities. Al出ough color has been considered for use as a visual repellent for chasing bird pests， no scientific inforτnation on common color prefer巴nceamong Japanese wild birds has been published to date. This experirnent therefore attempted to evaluate color preference among wild birds in Japan.
The results showed that no birds selected yellow or
blue as血eirvery first choice. In addition， all of出巴
birds gave a high score to y巴llow，and most of the birds also gave a high score to blue. These suggest出at yellow and blue are less prefe町巴d colors. These findings partly corroborate pr巴viousstudies in other bird species， which showed that blu巴 wasthe least at仕activecolor for birds (Gion企iddo& Best 1996; Hartley et al. 1999; Hartley el al. 2000). However， yellow was an attractive color in most studies (Gion企iddo& Best 1996; Hartley et al. 1999; Hartley et al. 2000). Two factors may explain the apparent
COLOR PREFERENCE IN JAPANESE Wll，D BIRDS inconsistency regarding the observed reactions to color
stirnuli reported in the literature. First， since there is currently no specific information on color preference in various wild birds in Japan
，血
epresent results may be也
efirst evidence to show也
atwild birds in Japan have characteristic color preferences. Second， the previous studies presented color stirnuli in出
eform of colored bait. However， food preference may not be influenced by color alone， but also by whether也
ecolored food appears palatable (Gamberale‑Stille & Tullberg 2001). Thus， in the previous s加diesemploying colored bait， birds may have preferred yellow sirnply because the food appeared more palatable. Since也
1S S田今rpresented color cues on
也
efeeder covers， the color preferences observed among birds in也
isstudy cannot be considered to have been influenced by也e appear組 問 ofpalatability.In也i
sway， the observed results are considered to be similar to也
ereactions of birds toward colored covers or flags也
atprotect bird attractors.The findings of the present study demonstrated
也
at， since yellow was less preferred by Japanese wild birds， yellow would be better suited for use as a visual repellent， p釘ticularlyin也
efomi of colored covers or flags. By extension， blue would also be good， but red and green would be less suitable for use as visual repellents.However， color alone cannot elicit sustained avoidance responses， even if a particular color is
紺ongly avoided initially (Hartley et al. 2000; Clapperton et al. 2011). Over time， birds would learn
白 紙 也
eaversive color may in fact be associated with担 at仕activeresource instead of with danger. Thus， to make color repellents more effective and sustained， it would be more effective to use a visual repellent as the key stimulus responsible for inducing the avoidance response， 組d也.ento augment
白
atinitial dete汀'ence with aversive stimuli such田 chemosensoryrepellents (e.g. repellents associated with taste aversion or ga位 ointestinal malaise) or企
ightening agents (e.g. warning shots or合 同
ng)to induce avoidance learning.Wh
en also using a cover or flag to induce avoidance learning， yellow might be也
eeffective color. Ham et al. (2006) reported也
atexperimenta1 prey with yellow cover was avoided significantly more出 姐
prey with a red cover after taste aversion conditioning to prey of both colors. In
order to m部 出 世 田 也epotential e自 治
ctiveness of colot as a practical repellent， the methods of也.epresent study should be inco中orated into an investigation examining which colors are more memorable when used as visual cues for avoidance learning， and whether color cues c姐 be used to exclude bird pests even when the attraction is not food， e.g. public spaces or articles.References
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onsesofred‑winged blackbirds to multisensory repellents Crop Protection 16， 159‑164.
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eUSDAlW
ildlife Services progr釦 1.International Biodeterioration&
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ano HE. 2004. Invasive birds in Japan. Global Environmental Research 8，
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Japanese).Mason JR， Reidinger RF. 1983. In1portance of color for
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COLOR PREFERENCE IN JAPANESE WILD BIRDS
日本産野鳥 8 例の飼育実験による色選好性試験
上野安貴l，東野晃典七高橋麻耶三近江谷知子4，鈴木友ぺ鈴木馨'*
l東京農工大学農学部附属広域都市圏フィールドサイエンス教育研究センター，府中市， 183・8509
2横浜市立よこはま動物園，横浜市， 241・0001
3横浜市立金沢動物園，横浜市 236‑0042
4横浜市立野毛山動物園，横浜市 220・0032
勺
11崎市夢見ヶ崎動物公園，川崎市 212‑0055*Corresponding author. E‑mail address:[email protected]
j .
p要 約
野生鳥類による食物や人工物への被害を防ぐ方法として、防鳥資材の活用がある。色は防鳥効果を 持つ視覚的なシグナルとして知られるが、実際にどの色が回避されやすいのかを多種について調査し た例は日本にない。本飼育実験では、日本国内に生息するスズメ(Pα，'Ssermon
ω
nus)、キジバト (Streptopelia orienω
lis)、コジュケイ(Bambusicola的
oracicα)、ツグミ(Turdusnaumanni)、ヒヨドリ (Hypsipetes amaurotis)、ハッカチョウ(Acridotherescristatellus)、オナガ(Cyanopicacyana)、トピ(Miル
us migrans)の計8種について各色の選好性を調査したところ、一貫性のある所見を得た。色の選択肢は 赤、黄、緑、青の4
色とし、これらの色の蓋によって覆われた4
つの餌入れを同時に提示し選択させ ることで、実験を行った。実験開始時の最初の選択において、黄および青を選択した個体はなかった。また、黄は全個体において回避される傾向にあり、青も多くの個体において回避された。一方で、多 くの個体が赤と緑に対し選好傾向を示した。この結果、黄・緑間では選好性に有意差が見られた。本 結果は、黄は防鳥効果が高く青も比較的鳥害予防に活用しやすいと考えられるが、赤と緑は防鳥効果 があまり高くない可能性を示唆している。防鳥効果の高い色をより効果的に且つ長期に亘って活用す るためには、これを単独で用いるだけでなく、化学忌避剤や威嚇による追い払いといった他の忌、避刺 激と組み合わせる研究が有効であると考えられる。
キーワード:野生鳥類，視覚的忌避刺激，色の選好性，事例研究，黄色
Animal Behaviour and Management， 49 (4): 164・170，2013 (2013. 7. 30受付;2013. 1
