139

Conflict between Humans and Crows in Greater Tokyo— Garbage Management as a Possible Solution —Reiko KUROSAWA1*, Yutaka KANAI2, Michio MATSUDA3 and Masaki OKUYAMA4
1

Biodiversity Lab, Institute of Low Temperature Science, Hokkaido University,
Nishi 8-chome, Kita 19-jo, Kitaku, Sapporo 060-0819, Japan2
Wild Bird Society of Japan, 2-35-2 Minamidaira, Hino, Tokyo 191-0041, Japan3
6-15-14-702 Honkomagome, Bunkyoku, Tokyo 113-0021, Japan4
Wildlife Division, Ministry of the Environment, 1-2-2 Kasumigaseki, Chiyodaku, Tokyo 100-8975, Japan(current association: Nature Conservation Bureau, 9-5 Honcho, Nikko, Tochigi 321-1434, Japan)* e-mail: rkurosawa@nifty.com

Abstract
Complaints by the citizens against crows increased during the 1990s in Tokyo, mostly because
crows’ scavenging caused a mess at communal garbage collection stations. We conducted a few pilot
studies on counter-scavenging measures and assessed those of local governments so as to find possible
solutions to conflicts between man and crows in urbanized areas. Assessment of social aspects wasdone by questionnaires to the citizens, and field surveys on the actual state of crows and garbage.
The citizens’ complaints had biases. Their value, therefore, was limited as an indication of theexistence of conflicts. The field surveys revealed that crows occurred at higher densities in central
Tokyo than in the suburbs, contrary to conventional concepts. Compiling the results of the complaints
and analyzing the field surveys were two indispensable procedures to seek for possible solutions.
The assessments of the pilot projects showed three realistic approaches to countering the
scavenging of garbage. Reducing the amount of food scraps was the only solution that would work
against all types of scavengers. The second option was the temporal segregation of food scraps fromdiurnal scavengers (midnight/early morning garbage collection and time-specific collection). Spatial
segregation of garbage from scavengers by protective nets and containers had variable effects.
The responses to the questionnaires showed that where scavenging by crows decreased, so didpeople’s negative feelings towards crows. Therefore, we suggest that counter-scavenging measures
could solve a major part of the crow-man conflict in urbanized areas.
Key words: conflict, garbage, jungle crow (Corvus macrorhynchos), scavenging, urban residents

1. Introduction
The crow population in densely populated areas ofcentral Tokyo has increased since the 1980s (Kawachi& Matsuda, 1999a; Ueta et al., 2003). In the winterof 2001-2002, approximately 36,000 - 37,000 crows
were counted at their roost sites in Tokyo (Tokyo,
2002).
Consequenctly, complaints by citizens
against crows increased in the 1990s (Nakamura 1999;
Mitani and Momozawa, 2002). The contents of thecomplaints seem varied, such as crows’ scattering
garbage on the streets, assaulting people walking
unawares beneath their nests, and dropping feces on
the pavement or cars.
The garbage collection systems of Tokyo underwent a few major changes in the past (Ueta et al.,2003). In the 1950s, household garbage was collected from wooden boxes with lids installed on thestreets. In the 1960s when plastic came into wideuse, the garbage boxes were replaced by plastic
buckets with lids. Then in the 1980s, as plastic bags
came into common use, garbage in plastic bags was
put out at communal garbage collection stations on thestreets. In 1993, at the advent of the recycling movement, citizens were recommended to deposit garbage
in transparent plastic bags so as to ensure correctgrouping of the contents. The transparent bags haveenabled scavenging crows to locate food scraps moreeasily (Kurosawa et al., 2001; Ueta et al., 2003).
Large cages or boxes for depositing garbage prevent
crows from scavenging it. However, where roads are
narrow with heavy traffic in central Tokyo, they were
not welcome because they hinder traffic. Therefore
crows eat food scraps more frequently in theentertainment districts with many restaurants incentral Tokyo, where bags of food scraps are placed

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out in heaps, than in residential and rural areas(Kurosawa et al., 2000; 2003). Other cities aroundTokyo have taken some countermeasures against
garbage scavenging by crows.
A “Crow Symposium” series was held by the
Tokyo Chapter of the Wild Bird Society of Japan
starting in 1999 so as to raise awareness among
citizens and administrators (Kawachi & Matsuda,
1999a; 1999b; 2002). Field surveys in 1999 revealed
that the great majority of crows in central Tokyo(97%) were jungle crows (Corvus macrorhynchos)(Kurosawa et al., 1999).
Jungle crows are one of the largest crows,
weighing about 650 g with a body length of ca. 55 cm.
They are large enough to scare adult humans when inaggression. Since jungle crows are large omnivorous
birds with a predatory nature, other bird species
including raptors have suffered high predationpressure from the crows especially during the breeding season in Tokyo (Ueta, 1998; Nakamura, 1999),
causing some ornithologists concern about the consequences (Kawachi & Matsuda, 1999a).
As the complaints of the citizens against crows
increased and the media covered crow problems as
well, the Tokyo Metropolitan Government started todestroy crow nests as a countermeasure against
man-assaulting crows in 1999. They also started tocapture free-flying crows in traps in 2000. The
Ministry of the Environment made a pilot study andpublished a manual for reducing conflicts between
city dwellers and crows in 2001, focusing on theimportance of proper garbage management. The
manual of 2001 is but a voluntary guideline, and local
governments can choose not to follow it. Also notmany governmental projects in Japan have scientificadvisory boards, or follow scientific assessment procedures (but see Kawashima, 2002; and Ministry of theEnvironment, 2001). Furthermore, there is no organization designated to make impartial assessments of theeffects of projects, and amend the original plans if
necessitated. Therefore, once started, a project may

Fig. 1 Map of study sites.

proceed un-amended even if it is ineffective, hasside-effects or is outdated. An action plan to reducethe conflict between man and crows in heavily populated areas will be best developed based on accurate
knowledge of the causes and mechanisms of theconflict.
In this historical context, we report on a pilot study
aimed at:1) determining the conflicts between humans andcrows by analyzing complaints against crows fromcity dwellers,2) clarifying the causes and mechanisms of theconflicts, and3) assessing the advantages and drawbacks of various
measures taken to reduce the conflicts.
This study was mostly based on the pilot study
sponsored by the Ministry of the Environment (WBSJ,
2001). Five municipalities and their citizens in andaround Tokyo cooperated in this study. Many supporters of the Wild Bird Society of Japan helped
conduct the field survey. This study would not havebeen possible without the collaboration of thesepeople. We express our greatest gratitude for theirsupport.

2. Methods
The study areas were located in greater Tokyo(Fig. 1).
Five local governments (Shinagawa,Setagaya, Mitaka, Hino and Kawasaki) cooperated inthis pilot study. Shinagawa and Setagaya Wards are
members of the 23 special administrative wards(districts) of Tokyo and are located in central Tokyo
with population densities of 14.0 thousand/km2 and13.5 thousand/km2, and vegetation coverage of 12%
and 20.5%, respectively. Mitaka and Hino Cities are
situated in the suburbs about 18 km and 35 km west ofcentral Tokyo, respectively.
These cities havemoderate population densities (9.9 thousand/km2 and6.0 thousand/km2, respectively) and relatively highvegetation coverage (23.7% and 38%, respectively).

Man-crow conflict in urbanized areas

Kawasaki City, Kanagawa Prefecture, is a large
industrial city south of Tokyo with a population
density of 8.7 thousand/km2 and vegetation coverageof 27%. Each of these municipalities started acrow-related project of its own in 2000 (Table 1).
Therefore we either conducted a new pilot study in
our research, and/or made assessments of the original
projects that had been started by the local
governments.
2.1 Analysis of social aspects through inquiries
In order to get a grasp of the conflicts between
humans and crows, first of all, we analyzed the social
aspects of the conflict by analyzing complaints against
crows that the city offices received from the citizens.
Most of the complaints were made by telephone andwere received in the municipalities’ environment divisions, except for Kawasaki (the agriculture division).
We classified the complaints into “garbage scattering,” “assaults on humans,” “noise and repulsiveness”
and “others.” We also checked the dates of the complaints to see if the complaints showed seasonal
differences.
We sent out questionnaires to citizens of the threecities and two wards in order to compare ordinary
citizens’ feelings towards crows with those of thecomplainants. The return rates were as follows;
Shinagawa 17.4% (N = 2000), Setagaya 80% (N = 20),
Mitaka 19.7% (N = 2000), Hino 77.3% (N = 300) and
Kawasaki 62.5% (N = 16).
2.2 Field survey on crows and situations ofgarbage on the street
For the actual conflict of garbage scattering, we
censused routes of approximately 1 km along thestreets in these cities and wards, with 76 routes inTokyo and 50 in Kawasaki. We counted the numbersof crows and garbage stations along the routes. The
condition of garbage scattering was classified into fivecategories (none, <0.5 m radius, <1 m, <2 m and>2 m).
2.3 Experimental pilot studies
We also conducted various field experiments andmade assessments of the measures the five cities andwards had taken on their own to solve the conflicts in2001 (Table 1).
A “time-specific garbage collecting system” wasTable 1141

experimentally introduced in Shinagawa. The residents put out their garbage in specific time zones,
such as by 8:00, 10:00 or 12:00, so the garbage trucks
could collect the garbage soon after it had been put
out at the collecting stations. This was a measure to
reduce the time lag between garbage placement andcollecting. Besides this pilot study, this ward hastaken several other measures to reduce garbage
scattering on the streets. We have assessed theeffects of these measures. Focusing on busy restaurant areas, they have distributed buckets with tight lids,
and collect the garbage at around 7 o’clock in themorning, earlier than in the other areas of the ward, so
as to reduce the availability of garbage for scavengers.
They have also developed an original foldaway cage
to house garbage in plastic bags, which can be
flattened when not in use so as to allow smooth traffic
flow.
Official distribution of protective nets over garbage stations was first introduced by Setagaya Ward in
1995, the first time such a system was used in Tokyo.
In the present study, we devised nets lined with chainsas a weight to prevent crows from picking them up, or
the wind from blowing them away. We asked someresidents in Setagaya to use the chained nets andreturn the questionnaires on them.
Mitaka City has experimented with collection of
garbage at midnight in a busy shopping area near themain railroad station. Since this was the first midnight collection trial in Tokyo, there was concern
about negative side effects, such as the noise of thegarbage trucks at midnight that might disturb the
citizens in the neighborhood. Therefore, we assessed
the advantages and drawbacks of this system in our
research.
Hino City had successfully contained garbage
safely within large metal boxes with lids, until they
overflowed, as the amount of garbage increased in the
1980-1990s. As a means of reducing garbage, Hino
City decided to abandon the communal collection stations with the metal boxes, giving priority to enhancing recycling rates. The city asked the citizens to
pay for their garbage on the beneficiary payment
principle, and proposed to collect garbage fromindividual households. The citizens were concerned,
however, that garbage in the transparent plastic bags
sold by the city might attract crows. Thus we asked
some citizens to use our protecting nets lined with

Original measures by municipalities in the study area. * indicates pilot studies conducted in this study.

Objectives
Anti-crow measures
Garbage collection
systemGarbage management

Municipality
Shinagawa Ward-

Setagaya Ward-

Mitaka City-

Hino City

communal

communal

individual

individual at costs

buckets
early morning collection
foldaway cage* time-specific collection

net covering* net with chains* assessment of
midnight
collection* net with chains
PET meshcage-

Kawasaki City
pest control
crow counts
communal* foldaway cage

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chains and PET mesh cages for garbage and return thequestionnaires on them. The mesh cages were madefrom recycled PET bottles to enhance recycling. In
so doing, we assessed the effects and drawbacks of thegarbage reduction procedures of Hino City in our
research.
A pest control program had been carried out in
Kawasaki City in an agricultural context every year.
Although they killed about 200 crows each year,
complaints from farmers did not decrease. Therefore
Kawasaki City carried out biological research toestimate the number of crows and locate their roostsites, in order to identify the reasons the control
measure did not work. In this study, we asked somecitizens to use foldaway cages for garbage containment (Fig. 2) and return the questionnaires on them.
By analyzing the results of the field survey and thequestionnaires, we advised possible prescriptions forthe situation in Kawasaki City.
In this research, we assessed these various measures aimed at clarifying and decreasing the major
sources of friction between man and crows as
determined from the results of the questionnaires
returned from the citizens. Based on the assessmentand field studies, we suggested possible solutions tothe conflict between man and crows in an urban
environment.

3. Results and Discussion
3.1 Analyses of the complaints of citizens against
crows
The rate of complaints against crows varied among
the areas, with significantly more complaints incentral Tokyo (65 cases in Shinagawa and Setagaya
combined) than in the suburban-rural Tokyo (23 casesin Mitaka and Hino combined; χ2 = 10.98, df = 2,
P < 0.01). Kawasaki had the greatest number ofcomplaints, larger than expected (123 cases). The

Fig. 2

Foldaway garbage cage developed in Shinagawa Ward
(photo by E. Kubota, courtesy of WBSJ).

complaints were focused on crows’ assaults onhumans (49.3 ± 28.7%) and their noisy calls (39.4 ±
24.8%). There were differences among the ways
these cities responded to the complaints.
For
example, Mitaka City collected garbage fromindividual houses and held the citizens responsible forproperly managing their garbage.
Receiving
complaints about crows scattering garbage, therefore,
they advised the citizens to cover their garbage withprotective nets or put it in closed containers. However, Mitaka City considered it the city’s responsibility to protect the citizens from crows’ assaults, andconsequently they took some countermeasures against
aggressive crows, including the destruction of theirnests.
There was a seasonal fluctuation in the number ofcomplaints with a peak between April and June
(Fig. 3). The peak period coincided with the breeding season of crows, suggesting that the causes ofcrows’ aggression toward humans are closely related
to necessary conditions for breeding, such as protecting their own young.
The responses to the questionnaires returned byordinary citizens (N = 393) showed that the contentsof the trouble had different ratings from those of thecomplaints (χ2 = 57.93, df = 3, P < 0.001). “Garbage scattering” was rated as the most serious problem in this case, followed by “noisy calls” (Fig. 4).
On the other hand, “assaults on humans” wasconsidered less significant among the crow issues,

Fig. 3

Seasonal fluctuations in crow-related complaints.

Fig. 4

Details of conflicts between crows and city residents.
Numbers of inquiries used for the analysis are shown
above the bar. Multiple answers permitted.

Man-crow conflict in urbanized areas

suggesting that “assaults on humans” had been
over-represented in the complaints against crows
recorded in the city offices and in the media coverage.
Although the total number of crow-related
complaints may reflect the severity of the conflict between humans and crows, the contents of the complaints did not necessarily represent a real picture of
the problem. In analyzing crow-related complaints
from citizens, therefore, local governments shouldseek advice from avian ecologists and sociologists torecognize the real state of the problem.
3.2 The number of crows and garbage scatteringon the streets.
The road censuses revealed that crows were more
numerous in central Tokyo (5.6 ± 1.1 crows/km) thanin the suburbs (3.8 ± 0.6 crows/km) (Fig. 5). Thesedensities were lower, however, compared with theresult of another study which showed the densities of
21 birds/km in the commercial districts and 6.1birds/km in non-commercial districts of Tokyo in2000 (Kurosawa et al., 2001). This is probably
because all the four local governments of Tokyo
collaborated in this study had already started to takesome countermeasures against garbage scavenging bycrows. In Kawasaki, on the other hand, more crows
were counted in the suburban areas than in theindustrial and commercial areas (12.5 crows/km vs.
9.1 crows/km; Kurosawa et al., 2002). The crows ofcentral Tokyo were all jungle crows, accounting for
94 % of the crows observed at the study sites.
Carrion crows (Corvus corone) occurred at low
densities (0.2-0.8 bird/km) in the suburbs alone.
Although the density of crows was correlated to thenumber of citizens’ complaints (Z = 2.00, r2 = 1.00,
P < 0.05, n = 5), it did not explain the rate of complaints
by the citizens (Z = 0.60, r2 = 0.30, P > 0.05, n = 5).
Although crows scavenged garbage put out at thecommunal collecting stations at the study sites, thescavenging frequency was higher in central Tokyo(5.0 ± 0.7% of garbage stations) than in the suburbs(2.3 ± 0.5%). The level of garbage scattering wasmostly within a radius of 0.5 m, with a few cases ofmore than 2 m scattering. In Kawasaki where crows

143

occurred at high densities, scavenging frequency was
also high (7.0%). A larger number of crows wereobserved scavenging at the garbage stations in
Kawasaki (4.7 bird/km) than in the four districts ofTokyo (0.5-1.1 bird/km). The frequency of garbage
scattering was significantly correlated to the density ofcrows (Z = 1.80, r2 = 0.90, P < 0.05, n = 5), suggesting crows were responsible for garbage scattering on
the streets (Kurosawa et al., 2002). In Kawasaki City,
which had taken no official countermeasures against
crows scavenging at the garbage stations, garbage
scattering occurred at a great number of communal
stations.
3.3 Assessment of pilot studies against garbage
scattering
Finding garbage scattering to be the major crowissue in the urban areas, we assessed each countermeasure against crows’ garbage scattering.
Time-specific garbage collecting system: Thissystem was welcomed by the citizens in Shinagawa inthat it was effective at decreasing garbage scattering
by crows. The effect depended greatly on the collection time zone, however, with the greatest effect in the
8 o’clock a.m. zone, decreasing afterwards (Fig. 6).
It was more convenient for the citizens to put out theirgarbage at the collecting stations before the beginningof the 10 o’clock a.m. zone, suggesting that the mostsuitable time for this system is at or before 8 o’clock,before most commuters leave their homes. A smaller
proportion of the citizens considered crows troublemakers in the early morning collection areas compared to the other areas of Shinagawa.
Chain-lined protective nets: These nets used at
the communal collecting stations in Setagaya hadsome effect in reducing the level of garbage scattering(85.3%; N = 16). The effectiveness of the nets
largely depended on the way the citizens managed
their garbage. When some people place their garbage on top of or outside of the nets, crows will takethe opportunity to scavenge, resulting in garbage scattering. The results of the questionnaire showed thatcarrion crowjungle crow

Fig. 6
Fig. 5

Mean density of crows (/km) in town (2001 winter).
(Modified from WBSJ 2002.)

Assessment of time-specific collection system in
Shinagawa. Results of inquiries of citizens.
Numbers of inquiries used for the analysis are shown
above the bar.

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medium-sized nets (3.2 kg) were easy to use, butlarger ones (4.1 kg) were unmanageable for seniorcitizens in particular. Small-medium sized communal garbage stations will be effectively protectedwith the nets, but some other measures will be required for large garbage stations with greater numbersof users.
Midnight garbage collection: This measure wasfavorably received in the entertainment districts of
Mitaka City. It was highly effective in preventing
crows from scavenging at the garbage stations, and thenumber of citizens in the midnight collection area who
noticed garbage scattering was significantly fewer(19.0%) after midnight collection began than before(88.2%; N = 195, χ2 = 11.15, df = 1, P < 0.001). The
most frequent level of scattering shifted fromscattering of more than 2 m in diameter before thestart of midnight collection (34.3%; N = 172) to thatof less than 1 m after the introduction of midnightcollection (32.4%). In the areas where midnightcollection was introduced, significantly more citizens(26.5%; N = 393) stopped considering crows troublemakers, compared to 7.1% in the conventional collection area (χ2 = 13.86, df = 1, P < 0.001). Interestingly, citizens felt that garbage scattering was reduced
also in the areas outside of the midnight collection
zone after midnight collection was introduced. Since
it is unlikely that crows have stopped visiting all of
the garbage stations in this city, this phenomenon
needs an explanation beyond our scope of study, suchas psychological or social aspects.
Garbage collection from individual households at a
cost: Garbage scattering observed in Hino City wassignificantly reduced after the introduction of thebeneficiary payment system from 91.0 to 43.8% (N =293; χ2 = 4.59, df = 1, P < 0.05). Also “chain-linednets” (87.0%, N = 200) and “PET mesh cages” (93.5%,
N = 46) were both well received as effective devices
for preventing garbage scattering. Many respondents
to the questionnaire (69.6%; N = 255) replied that theamount of flammable household garbage decreased
after the introduction of the new system, probably due
to the increased amount of waste materials going forrecycling. As for the level of scattering, heavy
scattering decreased (Fig. 7), probably because theamount of waste materials in the bags was less than
before.
The effect of decreasing the level ofscattering was observed for all the measures taken toprevent garbage scavenging. Therefore, the level aswell as the frequency of garbage scattering may be
regarded as an indication of the seriousness of thegarbage scavenging in an area.
Results of the field survey in Kawasaki City: The
survey showed that a large amount of food scraps wasregularly fed, both intentionally and unintentionally,to crows and other scavengers in a wholesale market,
situated close to the farming area where there werecomplaints of crop damage in Kawasaki. The crows
that had been attracted to the market were probably

Fig. 7

Level of scattered garbage before and after the
introduction of beneficiary principle in Hino City.

responsible for the damage.
Therefore, proper
management of food scraps in the market should
greatly reduce the conflict between the farmers andcrows.
The results of a questionnaire given to city
residents (N = 10) in Kawasaki City showed that themost serious crow issues were garbage scattering(70%), and noisy calls (70%). Most respondents(88.9%; N = 9) found that foldaway cages for containing garbage bags were easy to handle and highly
effective in preventing crows from scattering garbage.
In addition, many citizens in the vicinity of the areas
where foldaway cages were installed felt that the
number of crows decreased (77.8%).

4. Considerations for Solutions
The driving forces raising concerns among local
government administrators about crow issues werecomplaints from citizens and coverage by the media.
It turned out, however, that their complaints did not
represent crow issues correctly. The greatest issue inTokyo was the scavenging of garbage by crows in thestreets, rather than their assaults on humans. It istherefore recommended to use complaints from citizens as an index of the presence of conflict, but thatanalyses and advice from scientists be sought before
action plans against crows are considered.
Contrary to conventional ideas about wildlife, thefield survey revealed that crows occurred at higher
densities in more densely populated central Tokyo
than in the suburbs. Information on the locality of
hot spots is indispensable for taking effective measures. Combining the results of complaint analysis
and those of the field surveys is an indispensable
procedure that will indicate specific measures forsolving conflicts between man and wildlife such as
crows.
The assessments of the pilot projects showed three
realistic approaches to preventing crows fromscavenging garbage (Table 2). The function of midnight garbage collection was temporal segregation offood scraps from diurnal scavengers such as crows,
while protective nets and garbage containers have theMan-crow conflict in urbanized areas
Table 2

145

Functions and targets of counter-scattering measures assessed in this study.

Methods
Early morning collection
Midnight collection

Function
Temporal segregation of foodresources

Target wildlife
diurnal scavengers(crows)Nets
Buckets
Containers
Reduction of garbage

Spatial segregation of food resources

small-medium sized
diurnal & nocturnal scavengers(crows, rats, cats, foxes, boars)
all scavengers(crows, rats, cats, foxes, boars, bears,
humans)Reduction of food resources

function of spatial segregation. Reduction of theamount of garbage through recycling resulted in adecrease in food scraps available for urban scavengers.
Among the three approaches, reducing the amount ofgarbage was the ultimate solution without drawbacks.
This measure needs a mutual consensus by theadministrators and citizens, as well as ample time forpreparation before actual introduction. Temporalsegregation measures seemed to have short-term
effects against scavenging crows in Tokyo.
A
mid-night collecting system, however, may eventuallyattract nocturnal scavengers, such as rats and cats.
Introducing this system without reducing the amountof food scraps would then lead to an increase innocturnal scavengers instead of crows. In addition to
nocturnal scavengers, the food-searching activities ofstreet-dwelling people will defy the temporal andspatial segregation of food scraps from street animals
because of removal of the lids of dustbins or nets ofgarbage stations. An estimated 6,000 homeless people lived on the streets of central Tokyo as of 2003
(Ministry of Health, Labour and Welfare, 2003). The
effect of any collecting system, therefore, would benull if the amount of food scraps remains great. Of
spatial segregation measures, protective nets werelimited in effectiveness, because crows learn to drawout food scraps through the net in a short period oftime. Still there is a report that a pair of jungle crows
shifted its home range away from the communal
garbage stations as protective nets were introduced(Matsubara, 2003), suggesting the nets had the effectof making food scraps unavailable to crows.
Therefore, it is recommended that other measures
such as temporal and/or spatial segregation be used as
short-term measures until garbage reduction is
actually carried out and takes effect.
It is rather immature to consider that “crows arebad, and humans are their victims,” because crows arenaturally attracted to food sources that come out ofhuman society in many cases (Kurosawa et al., 2003).
Therefore we should keep in mind that no such living
things as “pest species” or “unnecessary species” exist,
because all species of life are ecologically interrelated
through the food web, constituting biodiversity onearth. Moreover, history has remonstrated us against
simple-minded “pest controls,” which have veryfrequently induced other unexpected disasters, such as
an explosive increase in prey species (insects) of acontrolled species (crows) (Forbush, 1927; Inoue,
1950; Inugai & Haga, 1953). Thus a balanced
approach should be sought to solve such issues as theconflict between man and crows (Fig. 8; Ministry of
the Environment, 2001). The procedures for settling
this issue need both social and ecological perspectives,and hence full cooperation among administrators,
scientists (such as ornithologists and ecologists), andcitizens. The reduction of garbage itself throughrecycling or other efforts supports holistic approaches
to coping with man-crow conflicts (Kurosawa &Kanai, 2001; Kurosawa, 2002). In order to facilitate
garbage reduction, however, it is necessary to raise
citizens’ overall environmental awareness, and that
leads to modifying their lifestyle as well. If humans
cannot even live in harmony with crows, they will getalong still less with wildlife in general. Therefore,
government administrators need to be aware of their
responsibility to make an effort in cooperation with
scientists and leading citizens to raise the awarenessof citizens about coexistence with wildlife.
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