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Citation: Japan's Territories Series, Japan Digital Library (March 2016),
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The Senkaku Islands in the Context of the History of theModern Fishing Industry in Okinawa *Makomo Kuniyoshi

1.

An Overview of the Islands

China
180 nautical miles(330 km)
90 nautical milesUotsuri Island(170 km)TaiwanIshigaki Island
90 nautical miles(170 km)

Okinawa Island
225 nauticalmiles(410 km)

Position of the Senkaku Islands (Uotsuri Island)(Map produced by Region 11, Japan Coast guard)

First of all, I’d like to give you an idea of the location of the Senkaku Islands. This is a map
produced by the Japan Coastguard. The islands are approximately 410 km from the main islandof Okinawa. From Ishigakij Island, it’s around 170 km, and roughly the same distance from
Taiwan. They’re approximately 330 km from the Chinese mainland and quite a substantial
distance separates them from any of the other islands around in the surrounding area. The
islands are therefore located in a position in the East China Sea that makes them, if not exactly
isolated, then at least quite far away from the nearest land.
What we generally refer to simply as the “Senkaku Islands” consists of five islands, the largestof which is Uotsuri Island. Close to Uotsuri Island are Minamikojima Island and Kitakojima
Island. A little north of these is Kuba Island, and to the east of that is Taisho Island. These five*

This article was originally published as 國吉まこも「沖縄近代漁業史から見た尖閣諸島」沖縄
大学地域研究所（編）『尖閣諸島と沖縄』芙蓉書房出版、2013 年、92-122 頁.

1together make up what we now refer to as the Senkaku Islands. Let’s take a brief look at someof the islands individually. Uotsuri is shaped like a mountain. People who have visited theisland and carried out an on-site survey there describe it as being “like a mountain looming
suddenly out of the sea.” This is an aerial photograph of the island taken by the Ministry ofLand, Infrastructure, Transport and Tourism in 1978.

Uotsuri Island(photograph: Ministry of Land, Infrastructure, Transport and Tourism, 1978)

The south coast of Uotsuri Island(photograph: Tomohide Nohara, 1971)

It’s a little hard to see from this photograph, but mountains from 350 m to 250 m in height run
across the island stretching from east to west. The south side of the island is quite severe, linedwith a series of cliffs and escarpments. This is a photo showing the south side of the island seenfrom the sea. This is the scene that greets anyone who travels to the islands. Close to Uotsuri
Island are Minamikojima and Kitakojima. These are considerably smaller but similar in nature,
resembling Rocky Mountains rising out of the sea—seen from the air, this is what they look like.
On the left is Kitakojima, with Minamikojima on the right. Minamikojima consists of a large
rocky mountain on the left side and narrows to the right. There is hardly any vegetation—crops
won’t grow and of course there is no drinking water. The island is a haven only for seabirds.
A little north of Uotsuri Island is Kuba Island. This island is a little different from Uotsuri Islandand Minamikojima and Kitakojima. As you can see, it has a more gentle topography and might
possibly be suitable for planting crops.
Taisho Island is another rocky mountain.

2

From some time in the Meiji era, people started coming to these five islands from Yaeyama forfishing.

Kitakojima (left) and Minamikojima(Photograph: Ministry of Land, Infrastructure, Transport and Tourism, 1978)

Kuba Island(photograph: Mainichi Shimbun)

2.

Fishing in the Senkaku Islands Prior to their Incorporation into Japanese territory
1885

Since 2011, Ishigaki City has declared January 14 a special day to commemorate the pioneeringdevelopment of the Senkaku Islands. A survey of the Senkaku Islands was carried out in 1885
by Okinawa Prefecture and 10 years later in 1895 a cabinet decision was taken to incorporate
the islands into Japanese territory. This ten-year-period tends to be regarded as something of a
blank, but in fact it was during this time that fishermen from Okinawa started to travel to theislands, building small huts and other structures there. I believe that the foundations for thefishing industry and other developments were more or less established in those years. How far
back do these activities go? Was fishing already underway by the time of the survey in 1885?
Let’s examine this question first.
In the summer of 1885 an internal order came from the Interior Ministry to Okinawa Prefecture,
instructing to carry out on-site surveys of uninhabited islands in the prefecture. Okinawa
Prefecture appointed a team of five under Hyogo Ishizawa (Fifth-grade industrial director of
Okinawa Prefecture) to carry out a survey. On the steamer Izumomaru, Ishizawa and his teamstarted by landing and carrying out a survey on the Daito Islands in August. This was followed
by a preliminary fact-finding survey on the Senkaku Islands in September. A man named Eiho
Oshiro, who was a local official of logging in Misato Magiri, had traveled between Ryukyu andFuzhou several times before Ryukyu became a prefecture and therefore had a first-hand3

understanding of the kind of places the Senkaku Islands were. After interviewing him andgetting a broad impression of the islands, the team carried out an on-site survey in October, thefollowing month. The survey team under Ishizawa arrived on the Izumomaru and went ashore at
Uotsuri Island. The report stated: “Large numbers of albatross gather on the islands. Largeamounts of wreckage lie along the shore, washed up here from boats from Ryukyu and Chinathat have foundered nearby, but there was no sign of inhabitation.” The report concluded thatthe islands were uninhabited. At this time, therefore, fishing had presumably not yet started. It
seems reasonable to conclude that fishermen had not yet reached the islands at this stage.
To return to the report, it says “Although the coasts are rich in marine resources, there is little
flat land on the island,” which is very much like a mountain. The survey concluded that theislands were “unsuited for establishing industries such as cultivation or fishing,” and the report
was duly submitted to the prefectural government.
I should point out that the team was only able to actually land on Uotsuri Island. The weather
conditions had deteriorated by the time they visited Kubo Island and Taisho Island and the teamabandoned the idea of making a landing on those islands because the waves were too high.
The team caught a number of albatrosses alive from Uotsuri Island and tried to breed them atthe prefecture’s industrial experimental center in Naha. Anyone who visited the center at thetime might have seen albatrosses from Uotsuri there.
Following the report, the Okinawa governor Sutezo Nishimura petitioned to the Interior
Minister Aritomo Yamagata that the islands should be officially incorporated as part ofJapanese territory.
At first, Yamagata was in favor of incorporating the islands, which seemed to be uninhabited.
He consulted the Minister of Foreign Affairs Kaoru Inoue about the matter, but Inoue had adifferent opinion. He argued that “I hear the islands are located between Ryukyu and Fuzhou
and have been known by both Ryukyu and China for many years. The islands even have
Chinese names.” “Islands with names like Chogyodai (Diaoyutai), Kobisyo(Huangweiyu), or
Sekibisyo(Chiweiyu) should not be unilaterally incorporated into our territory without giving it
a second thought, simply because they are uninhabited.” Yamagata was persuaded by thesearguments and a reply was made to Okinawa Prefecture to the effect that incorporating theislands was not necessary.
At this stage, then, there were no signs of fishing on the islands, and although a survey was
carried out, it led to a clear decision that there was no need to incorporate them as part ofJapanese territory. Five years later, the situation was different.

4

3.

1890

By this stage, we now have confirmed signs that fishing was going on. In 1890, five years after
the survey, a large number of specialist fishermen from Itoman in Okinawa had made their way
to Kuba and Uotsuri Islands where they had established a base from which to fish in thesurrounding waters. Concerned about this development, the head of the local government officein Yaeyama, Tsunenori Nishi, sent a request to Okinawa Governor Kanji Maruoka for placing
the area under the jurisdiction of the Yaeyama Islands.
Let’s look at what happened in a little more detail. In 1889 an entity called the Yaeyama
Fisheries Cooperative [Yaeyama Kyodo Suisan Kaisha] was formed with public funding.
Toward the end of that year, on December 25, 1889, the local government office in Yaeyama
inquired to the Okinawa governor, referring to the Senkaku Islands where the prefecture had
previously carried out a survey and requesting that the islands be placed under its jurisdiction
for the purposes of fishery control. This request evidently failed to provide a full enough picture.
In January the following year the prefectural government replied saying that theyneeded detailed information on the situation regarding local fishing control, without which they
could not form a true impression of the situation. On January 10, a reply came from Yaeyama,
local government saying that the Yaeyama joint Fisheries Cooperative that had been licensed in
the previous year was now operating in the Senkaku Islands and that the office wanted theprefectural government to issue instructions relating to this.
This makes it clear that groups of fishermen were now moving to the Senkakus from Yaeyama
at this time. The Yaeyama Islands Local Office approached the prefectural government to
explain that given the reality of the new situation it surely made sense for the islands to beplaced under their jurisdiction.
How did the prefectural government office respond? Three days later, on January 13, a petition
was issued from the Okinawa Prefectural Governor to the Interior Minister titled ”Inquiry on
uninhabited islands of Kuba and Uotsuri”. The message was essentially a request of anincorporation of the islands into the territory. They requested the Senkaku Islands be placed
under the jurisdiction of the Yaeyama Islands for the purpose of controlling fishermen who werecollecting marine products. An exchange followed through January and February between theofficial in charge of prefectural affairs in the Interior Ministry and the governor of Okinawa.
The Interior Ministry said it lacked a clear understanding of the details and asked Okinawa
Prefecture to submit a detailed report of the survey it carried out in 1885. Okinawa Prefecture
duly gathered the materials and sent them to the Interior Ministry. But there was no reply from5the Interior Ministry and no instructions were issued regarding the incorporation of the islands.
This situation continued until in April that year Okinawa Prefecture instructed a prefectural
officer named Tadao Hanawa to complete an interview survey on the state of fishing in the
Senkaku Islands. Hanawa carried out interviews with Itoman fishermen returning to the port in
Ishigaki from the Senkaku Islands. The interview revealed that 78 fishermen were staying in the
Senkaku Islands at that time, including 32 who had reached the islands on the steamship
Taiyumaru, 26 who had come on a katsuo-sen and 20 from Yonaguni Island. At the time aregular ship service navigated what was known as the Sakishima route that linked Naha in
Okinawa with the Sakishima islands: Miyako, Ishigaki, Iriomote, and Yonaguni Islands.
Taiyumaru was the steamboat used for this service. The report writes that 32 fishermen had
traveled to the Senkaku Islands on this ship. It is unclear whether they chartered the ship or
simply asked for it to divert from its regular route. Also recorded are 26 men from a katsuo-sen(literally a bonito fishing boat). This is likely to have been a Japanese-style fishing boat or aslightly larger tenmasen (another traditional style of Japanese boat). Bonito fishing had not
begun in Okinawa at this time, so it is unlikely to have been an actual bonito fishing boat.
Anyway, these fishermen reached the islands on some boat of that kind. Another mention ismade of “20 men from Yonaguni Island.” These people simply crossed the sea in their own
sabani (traditional Okinawan style boats) or tenma fishing boats. This made for a total of 78
people who had traveled to the Senkaku Islands at that time, where they collected marbled
turban shells (turbo marmoratus) and other shells. The people had built small huts and there
were plans for settlement on the islands. This was the conclusion of the survey that was reported
to the prefectural government.
Incidentally, this record of the state of fishing in the Senkaku Islands in 1890 is corroborated byanother source, an article titled “The Marine Products Industry in the Southern Seas” in the firstissue of a magazine called Okinawa Seinenkai-shi [Journal of the Okinawa Youth Association],published that same year. “Mr Jinnosuke Matsumura, who has lived in the Yaeyama Islands for
45 years and now works at the Yaeyama Fisheries Cooperative there, traveled last February
from Yaeyama with some 70 fishermen to an uninhabited island called Kobashima(nowSenkaku Islands) located some 90 nautical miles north of Yaeyama, and made huge earnings ina period of only three months.” The number of fishermen cited and the mention of the Yaeyama
Fisheries Cooperative tally with what we know from other sources. This magazine waspublished by a group of young men from Okinawa who were studying in Tokyo. It was
published in Tokyo. The information in the article about developments in the fishing industry
was presumably written based on some news one of these students received from home.
So I think we can safely conclude that by around 1889 when the Yaeyama Fisheries

6Cooperative was founded, fishermen were traveling to the Senkaku Islands from Yaeyama forseasonal periods and that fishing was already underway in the islands.
The next evidence we have concerns an expedition led by Izawa Yakita, a native of Kumamoto
who in 1891 took a group of Okinawa fishermen to Uotsuri and Kuba Islands, where theycollected albatross feathers and other marine products. The source says that the crossing was
made in a wooden kuribune (a kind of dugout) or tenma fishing boat. “We wouldn’t stay longon the island, but would always return home to Ishigaki port,” he writes. The men would set out
from Ishigaki Island in Yaeyama in small wooden boats with no engine power. They traveled to
the Senkaku Islands by rowing and by trusting their fates to the winds. Two years later, in 1893,
Izawa attempted the journey again but was caught in a typhoon on the way home and washed up
in Fuzhou lucky to escape with his life. Fishermen ran considerable risks when they set out for
the Senkaku Islands to collect albatross feathers and shells, returning if they were lucky to theport in Ishigaki.
In December 1891, the Okinawa Prefecture released an instruction titled “a matter on control of
the Daito Islands.” These were mostly concerned with bringing the Daito Islands east of
Okinawa under the jurisdiction of the Naha local office, but also touched on the Senkaku Islands,
referred to as Akon Kuba Island. (This spelling of Akon Kuba seems to have been devised as aphonetic equivalent of Yukun Kuba.) The document records that these islands should be
regarded as falling under the jurisdiction of the Yaeyama Local Office. The instruction notedthat the Head of Yaeyama Local Office has already issued a request to the authorities concernedthat these islands should be incorporated into local jurisdiction—this mention points to therequest we have already looked at that was sent in 1890. But there was no reply to this request
yet. The document goes on to say “geographically these islands clearly form part of the charted
territory of this country and as such should be regarded as belonging to our territory.” And in asecond issue of the instructions, Direction No. 45, it said “regarding the situation of the Daito
Islands, and regarding it as a matter of priority that these should be brought under the control of
the Yaeyama Local Office, we issue this set of instructions to that effect,” ordering that the
Senkaku Islands”Akon Kubajima” should be regarded as coming under the jurisdiction of
Yaeyama Office.
And then, as if still not satisfied, on January 25, 1892, the governor Kanji Maruoka sent arequest to the Naval Ministry asking that a complete survey of the uninhabited islands in theprefecture should be carried out, including naturally the Senkaku Islands. Maruoka wrote thatthe survey of 1885 had been insufficient, since the team had been able to visit only Uotsuri
Island, and he pressed the Naval Ministry to carry out another survey. Unfortunately the naval
sloop called the Kaimon that visited Okinawa in August that year did not carry out any survey

7

on the Senkaku Islands.
As mentioned above, in around 1890, fishermen started to head for the Senkaku Islands. Upon
learning of this, the Yaeyama Local Office, doesn’t try to stop the fishermen from going, butinstead, the officials decide that if fishermen are traveling there anyway it might as well request
the prefectural government to have the islands placed under Yaeyama’s jurisdiction. When it
receives this request the prefectural government in its turn decides to issue a request of its own
to the national government, carrying out a survey on the state of fishing in the islands and thenissuing instructions that although a previous request is still being considered, people should
regard the islands as belonging to the Yaeyamas Islands. On top of that, it asks the navy to carryout a second survey of the uninhabited islands. The islands evidently held considerable interest
for authorities in Okinawa Prefecture and Yaeyama in these years.
4.

1893

Our next piece of documentation is the Nantou Tanken (Exploration of the Southern Isles) by
Gisuke Sasamori in 1893, which contains its own appeal for the uninhabited islands to beincorporated into the territory. Sasamori was from a shizoku (ex-samurai) family in Aomori
Prefecture. He came to Okinawa in 1893 and traveled from the main island to Miyako Island,
Yaeyama, Ishigaki, Iriomote, and Yonaguni, landing on all these islands in person and carryingout detailed research on the state of the islands and their people at the time. After returninghome he wrote up his findings in a book. The book opens with a map showing “My route
through the islands of the southern ocean.” The Senkaku Islands are shown on the map as theuninhabited islands of Kumeaka, Kuba, and Tsuriuo.

Uninhabited island
Kumeaka Island

Uninhabited island
Kuba Island
Uninhabited island
Uotsuri Island

Yabiji reef eight ri (31 km) out.
Local sailors say more than ten foreign ships
have come to grief here.

Yaeyama
Hatoma Island Islands

Ogami Island
At northeast edge of said island

Miyako Islands
Ishigaki Island

Yonaguni Island
Funauki Port

Iriomote
IslandHateruma Island
17 W

16 W

15 W

Map showing Gisuke Sasamori’s route“through the islands of the southern ocean”

8

14 W

The map clearly shows the navigational route that passes through these uninhabited islands, as
marked by the dotted line.
In his book, Nanto Tanken, Sasamori included a section titled “A Personal View regarding theAdministration of the Southern Islands,” in which he suggested setting up administrative offices
on Miyako and Yaeyama Islands to exercise overall control of 20 outer-lying islands, including
Kumeaka, Koba, and Uotsuri Islands. It seems that the Senkaku Islands were something of anotable topic at the time, since Sasamori makes two mentions of the islands in the main body of
his text. Let’s look at them next.
The first mention comes in a description of two merchants from Kagoshima called Jinnosuke
Matsumura and Kiemon Nagai, who traveled with a team of workmen to the Senkaku Islands tocollect albatross feathers. Once a certain volume of these feathers had been accumulated, they
returned to the mainland, leaving their men behind with a promise to come back later. The
abandoned men waited, living off the sweet potato that has been transplanted to the islands, butthere was no sign of their employers. They were almost at the end of their endurance when they
were finally rescued by a group of Itoman fishermen who had come to the islands to gather
turban shells and taken back to Naha. You may have noticed that this is the second mention we
have had of Jinnosuke Matsumura—presumably the same person we previously encounteredworking at the fisheries cooperative and sending fishermen out to the Senkaku Islands from abase in Ishigaki.
The second reference mentions a plan for a fishing expedition to the Senkaku Islands by a teamof 16 men led by another shizoku, Tadashi Noda of Kumamoto Prefecture. This is based on an
account by Gisuke Sasamori based on what he heard in Okinawa. At the time, he writes, a teamof fishermen led by Tadashi Noda of Kumamoto had plans to set out to Senkaku Islands on afishing expedition. The plan received support from influential people in the prefecture andceremonies were held to see them off and wish them success.
Another document contains a slightly more detailed record of this plan, which I’d like toconsider now. According to an article, “A team of fishermen sets out to uninhabited islands” in“A Record of a Survey on the Yaeyama Islands in Okinawa”, a fleet of fishing vessels wasformed to set out for the uninhabited Senkaku Islands. The document records what kind of place
the islands were, and notes that these are “most rich in marine resources including shark, bonito,
whale, and shells including the marbled turban shell.” It also records that the group included ateam of specialized shell-gatherers and that “many people from Itoman were among the crew.”
It was probably in September when this information was gathered by Sasamori.

9Then in a letter dated November 2 the same year, the governor of Okinawa Shigeru Narahara
wrote to the Interior Minister and the Minister for Foreign Affairs with a third request for theislands to be formally admitted into Okinawa’s territory: “Petition Regarding Construction ofMarkers on Kuba Island and Uotsuri Island for Prefectural Jurisdiction.” This was presumably
prompted by the plan of Noda Tadashi and his associates.
These are the two incidents mentioned in the “Exploration of the Southern Islands” document.
Another example of developments at the time concerns fishermen from Itoman in the same year,
1893, who were evidently fishing in the Senkaku Islands. They traveled to the Senkaku Islands
on a fishing expedition but encountered bad seas on their return journey. This is recorded in the
kanpo, or official government gazette. The report records that at the end of 1893 a group offishermen from Itoman crossed to the islands for the purpose of fishing but encountered atyphoon during their return journey to Ishigaki. Three of the men were reported missing in theofficial report dated February 21 1894. As you have perhaps noticed, this is still before theislands were incorporated into Japanese territory. At this time, the islands still lay outside
Japanese territory, but nevertheless, fishermen were traveling there and mention of this wasmade in official government records.
These records documents are enough to demonstrate that even before the islands wereincorporated into Japanese territory fishermen and others were traveling to the islands forfishing, by chartering steamer boats or in their own boats from Ishigaki and Yonaguni. One of
the main items that people wanted to collect was the marbled turbo shell. This was largely
collected for export purposes, and it was popular with foreign traders who would eagerly buy
the shells as material for buttons. Albatross feathers were also valued for use in down quilts. A
quilt full of albatross feathers would have been too much of a luxury item for the people of
Okinawa or elsewhere in Japan at the time. They were mostly items for export, chiefly toEurope and America.
It seems that the fishermen normally stayed on the islands for two to three months at a time, orat the longest half a year. The environment wasn’t suitable for longer stays. The fishermen built
simple shelters and also transplanted sweet potato and other food crops around this time.
During the period of the Ryukyu Kingdom before Okinawa was incorporated as a Japanese
prefecture, the islands had been known as navigational landmarks on the route between Fuzhou
and Ryukyu. But from this period Kuba Island some 90 nautical miles north of the Yaeyama
Islands became recognized as a popular spot for fishermen seeking fish and other marine
resources. Following the Meiji Restoration businessmen and traders from other parts of Japan
were drawn to Okinawa, where they bought up large amounts of marbled turban shells and10albatross feathers for export. This is presumably why the Senkaku Islands began to appear in thevarious sources that can still be seen in the libraries of the prefecture today, including the
Okinawa Seinenkai-shi, Nanto Tanken, and the official gazettes. So far we have seen how
fishermen and others were traveling to the islands even before they were incorporated into
Japanese territory. Next I would like to consider the case of Tatsushiro Koga, famous as the man
who pioneered the development of the Senkaku Islands after they became part of Japanese
territory.
5.

Incorporation of the Islands and Development by Koga Tatsushiro

I have already mentioned the request issued by Okinawa Prefecture on November 2, 1893
asking for the Senkaku Islands to be incorporated into Japanese territory. This was sent by thegovernor of Okinawa Prefecture Shigeru Narahara. A reply came from the head of thedepartment of prefectural affairs within the Interior Ministry dated April 14 the following year,
1894. “That you request a formal incorporation of the Senkaku Islands,” it suggests, “you havepresumably already carried out a detailed survey of the islands.” The reply then asks for detailsof findings in a number of categories, including “the shape of harbors in the islands” and “theprospects for future development,” as well as “proof that the islands have belonged to Japan
since historical times, in the form of old records or oral traditions.”
Narahara replied in May. It’s a not a particularly informative reply. “Since we have not carriedout any on-the-site surveys since 1885, we are unable to provide any firm information from any
surveys beyond that.” In other words, he replied that they didn’t know much about the islands
beyond what was contained in the 1885 report. As a reply to the government’s enquiry, this wasa pretty poor effort. But somehow it was enough to start the Meiji government on making
moves to incorporate the islands into Japanese territory.
Seven months after Nakahara’s reply, in December 1894, a confidential cabinet memorandum
No. 133 is prepared on the matter of incorporating the Senkaku Islands into Japanese territory.
A discussion follows regarding the contents of the memorandum between Interior Minister
Nomura Yasushi and Minister for Foreign Affairs Mutsu Munemitsu. They conclude that there
is no reason to hold off on submitting the memorandum to the Cabinet meeting, and a cabinet
decision to incorporate the Senkaku Islands into Japanese territory is issued the following year,
dated January 14, 1895. The efforts of the three Okinawa governors who had petitioned thenational government to take this move—Sutezo Nishimura in 1885, Kanji Maruoka in 1890, andShigeru Narahara in 1893, had finally borne fruit. In September 1896 Okinawa Prefecture
awarded the Senkaku Islands to Tatsushiro Koga on a 30-year rent-free lease. This marked the
beginning of Koga’s development of the islands.

11

Fishing in the islands after they were formally incorporated became more or less the monopolyof Tatsushiro Koga. In the documents concerning fishing on the islands and the development of
the islands in the years that follow, his is almost the only name that occurs.
Given this, I’d like to take a few moments to sketch out his background and career and give a
brief summary of his development of the Senkaku Islands.
Koga Tatsushiro was born in Fukuoka Prefecture on January 18, 1856. He came to Okinawa in
1879, the year in which the old feudal domains were replaced by the new prefectures. Aftercoming to Okinawa he ran a trading business in Naha, and established a branch in Okawa on
Ishigaki Island in the Yaeyama chain in 1882. In the years that followed he made his fortune
exporting items from Okinawa overseas, chiefly marbled turban shell and other marine products.
In 1896 he began to work seriously on developing the Senkaku Islands. In the early stages thisdevelopment focused on Kuba Island, while in later stages much of the work was concentrated
on Uotsuri Island. In the early period he collected huge volumes of albatross feathers in addition
to the marine products caught by fishermen from Itoman. The albatrosses were hunted soaggressively that their numbers soon dropped dramatically. Beginning from around 1903 hiscompany produced stuffed specimens of tern species and sold them in large amounts for export
overseas. In 1905 he started bonito fishing and began producing dried bonito. The dried bonito
he produced mostly from his base on Uotsuri Island were shipped to Tokyo and Osaka and were
well reviewed at consumer product fairs. He also tried his hand at a business producing guano
for manure, but this was less successful.
As mentioned above, Koga ran a trading business based in Okinawa. Although he was also
known for developing the Senkaku Islands, he was better known as one of Okinawa’s leading
merchant dealing in marine products.
In a publication entitled “Directory of Traders and Craftsmen Nationwide in the Meiji Era,” forexample, Tatsushiro Koga is listed as the only marine products trader among various traders insugar and textiles under the section for Naha in the Ryukyu chapter. One of Koga’s strengths at
the time was that his brothers Kunitaro and Yosuke ran a Koga Trading store in Osaka that dealt
directly with the foreign merchants based nearby in Kobe. He would buy up marine products inbulk in Okinawa and send them to Osaka, where his brothers would sell them on to the foreign
traders. This situation made him the only trader in Okinawa specializing in marine products who
had his own channel for dealing with the foreign traders.
As well as developing the Senkaku Islands he also sent products to be exhibited and judged atvarious trade shows and fairs and won numerous prizes for products including dried bonito,

12dried squid, sea cucumber, shark’s fin, shells, feathers, and pearls. In particular, his pearls weresold several times to the Crown Prince at the time, who later became the Taisho Emperor. Koga
was widely recognized as one of the leading entrepreneurs and businessmen in marine products
in Okinawa at the time.
Around 1909, Koga was awarded the “Medal of Honor with Blue Ribbon” in recognition of hisachievements in the development of the Senkaku Islands and marine products trading. He was
the second man in Okinawa to be awarded this honor. The first was Wasaburo Matsuda from
Zamami Magiri, who was famous for starting bonito fishing in Okinawa. The development of
the Senkaku Islands was at its peak at this time, with 99 households of migrant workers and a
total of 248 people living on the islands.
Koga died on August 28, 1918. His son Zenji took over the company. At this period at the peakof the development of the islands the pioneers who lived and worked on the islands had comethere as employees of Koga. They would receive payment in return for agreeing to live andwork on the islands for a certain period of time, normally a year or six months.
One of the documents we have is an advertisement placed in thelocal Ryukyu Shimpo newspaper calling for men to work on
uninhabited islands. These are the Senkaku Islands. The wordingof the advertisement reads: “Now hiring migrant workers totravel to uninhabited islands Number of vacancies as follows
Positions on land: 40; Bonito fishing: 20; Clerical staff: 2.
Clerical staff must be at least 25 years of age and must submit a
resume. Those wishing to apply should present themselves by the
25th of this month. Dated: Feb. 6, Koga Trading, Naha-ku.”

Advertisement for works on
uninhabited islands

The company placed similar advertisements a number of times in the Ryukyu Shimpo, inviting
people interested in working on uninhabited islands to contact the company. These people were
migrant workers. The company recruited the necessary numbers and sent them in as workers to
the islands.
In another advertisement placed in the Ryukyu Shimpo on June
21, 1907, there was a call for a doctor. “One doctor needed, for
Waheiyama.” This was a term often used by Koga to refer to
Uotsuri Island. “Position requires residence on Kuba Island,
payment of 30 yen per month plus separate allowance formeals.” The advertisement says, “Wishing to recruit a person
fitting the preceding description, we call on any interested
Advertisement for a doctor
13persons to apply by the 27th of this month. Dated: June 21, Naha West, Koga Trading. The
steamship departing at the end of this month will make a deviation to the island, preparations ofletters and personal supplies to be made by the 27th of this month.” This mention of “letters andsupplies” mean letters and goods sent to the workers on Senkaku Islands from relatives in themain island.
Some 248 people were hired—not so much as pioneers to develop new territory than as migrantlabor employed to do a certain job. It was work that must have been quite difficult andunpleasant even by the standards of the times. This is what Koga himself looked like. The freshfaced fellow next to him is his son, Zenji.
And here’s another, this wasn’t taken in the Senkaku Islands but shows an Itoman fisherman
who was a friend of Koga. The man who took these pictures was Kakichi Mitsukuri, a science
professor at the University of Tokyo. He visited Okinawa to gather samples of sea cucumber
and other things, and Koga offered hospitality to the scientist while he was staying in Okinawa.
Koga introduced an Itoman fisherman he knew. It must have been men like these who weretraveling to the Senkaku Islands at the time, I think.

Yasutaro Tamagusuku(Nabisa)Zenji Koga

Tatsushiro Koga

Incidentally, this is a diagram showing the layout of the buildings on Uotsuri Island. You can
see the boat-building dock, work huts, bonito storage warehouses, and employee dormitories.
It’s all facilities like this—there are no personally owned houses or anything like that. The
whole area is taken up with functional buildings with designated purposes and a few bunks

14

where the workers could sleep. This is a sketch left in Koga’s own hand.

Land under development
Rock
Hill

Flat rock
Water
tank
Offic
e/
Hot
water
bath

PigstyWarehouse

Rock

Guest
quarters Workers’
kitchenShare Femaleworkdliving space
space
Femaleworkers’ kitchen

Workers’
bathhouse

Store
room

Sea workers’
accommodation

WarehouseSmi
thy

Three-story storage(stone)MulberryChildren’s
accom
modati Wareon
house

PigstyThe northwestern partof Uotsuri Islandaround 1910

Separate
guest
quarters

Tank
No. 1

Workspace
Wharf

Lat
rin
e

OfficeFirewoodstorageTa
nk
BonitoguttingandfilletingTwo-story
bonitoprocessing
tool storage

Cultivated
field

KitchenTwo-story accommodation
for bonito processing
workers

Bonito kettle
shed

Ammunition
storage

Preserv
ation
storage

Water
tank

Rock

Slope

KitchenFirewoodstorage
KitchenBoatyard
Dock

Cultivatedfield

Storeroom

Fishermens’
accommodation

Fishermens’
bathhouse

Workspace

Cultivatedfield
Cultivatedfield

Two-story
bonitoprocessing

Water tankWorkers’canteenLand workers’
accommo- 3 ken(approx. 5.4 m)
dationTwo-story
bonito warehouseOldsmithySalt making
shed

Plan
showinglayout ofbuildings on
Waheiyama

Boarding shed

5 ken
(approx. 9 m)

Layout of offices and other buildings on Uotsuri Island(around 1910, drawn by Tatsushiro Koga)

Now I’d like to return to the fishery business and talk a little about the various kinds of fishingthat were carried out during the Koga period.
6.

The Fishing Industry in the Senkaku Islands during the Period of Development

I mentioned earlier that Koga received a medal of honor from the government in 1909. At thistime he submitted a detailed curriculum vitae to the Meiji government, containing a detailed
account of his work in the Senkaku Islands among other endeavors. Let’s look at the fishing
operations that took place on the Islands at the time, using this document as a source.

15

Chief marine products of the Senkaku Islands

Type of fishing (including seabirds)

Time of start

Seabirds: Collecting feathers, manufactureof stuffed specimens, etc.

Feather business started around 1897
Taxidermy started around 1903

Collection of shark’s fin, shells, turtle
shells, etc.

Itoman fishermen already active in the area before
the islands’ incorporation into Japanese territory

Bonito fishing, manufacture of dried bonito

Started around 1905

The fishing carried out in the Senkaku Islands under Koga’s development can be broadly
divided into three categories. First there was the seabird business, which involved collecting
albatross feathers and manufacturing stuffed seabirds of tern. Second was the gathering ofmarine resources such as shark’s fin, shells, and turtle shell, and the third was bonito fishing andthe manufacture of dried bonito.
First, albatross feathers. In the early stages of the development, the feathers sold at a high price.
This was the main industry of the early period of development, and is thought to have been themain pillar that supported Koga’s business in the Senkaku Islands.
After receiving permission to start developing the islands, in 1897 Koga sent out his first batchof 35 workers. The following year, he borrowed a steamship called the Sumamaru from the
Osaka Shosen company and increased the number of migrant workers sent to the islands to 50.
Koga himself did not travel to the islands each time. Instead a man named Entaro Otaki, who
was apparently his nephew, traveled to the islands as supervisor.
The graph below shows the volume of feathers gathered based on figures provided in Koga’s
curriculum vitae. As a cursory look at the graph reveals, the volume increased dramatically inthe first three years. In 1897 the volume of feathers was given as 17,000 kin (one kin being
equivalent to 600g). By 1898 this had increased almost fourfold to 65,000 kin and by 1899 had
further increased to 85,000 kin. This rapid increase came to an end the following year, after
which the volume fell dramatically.

16

Annual “harvest” of feathers (in kin)

The reason was overhunting. The indiscriminate capture of the birds led to a dramatic drop in
the population. Something of the scale of the slaughter can be seen from an article in the Ryukyu
Shimpo dated June 25, 1900, titled “The Profits Remaining to be Made on Uninhabited Islands.”
According to the article, a single worker at the time would catch 300 birds a day. Within three
years, overhunting was a serious problem and, since the supply of birds was not infinite, thenumbers soon started to drop precipitously. There is a dramatic noticeable drop-off in thenumbers of birds taken after 1900.
Worried that his business might prove unsustainable, in 1900 Koga traveled to Tokyo. There heinvited the University of Tokyo scientist Kannosuke Miyajima to visit the islands and undertakea survey of the albatross population. Miyajima traveled to the islands together with Hisashi
Kuroiwa, a teacher at the Prefectural Normal School who is thought to have given the Senkaku
Islands their name. Miyajima’s advice was to limit the numbers of albatross taken so that
hunting did not affect their natural reproduction. This was sound advice but the graph reveals
what really happened.
The numbers never recovered, and by the postwar period albatrosses were extinct in the islands.
This picture shows a few albatrosses. This is a recent picture, from 2002 or so. It was taken by aphotographer called Kunio Mizushima. They are quite sweet birds but back in those days people
bludgeoned them to death in huge numbers for their feathers.

A sooty tern on Kitakojima(photograph: Yoshima Niiro)

Albatrosses on Minamikojima(photograph: Kunio Mizushima)

17

As the albatross population fell, the feather business could no longer sustain the whole company
and Koga had to shift to a new way of making money. The new idea he turned to again involved
seabirds, sooty terns and other species of tern, a seabird much smaller than the albatross. Again
the workers would catch large numbers of these birds and preserve them taxidermically forexport to Europe, particularly to Germany. This business began in 1903 when Koga hired 16
taxidermists in Yokohama. He established a taxidermy workshop on the coast of Minamikojima
Island where they produced stuffed terns and other species that were exported in large quantities
for use on ladies’ hats in Europe.
The graph only shows figures for four years, from 1904 to 1907. In 1904, 130,000 birds weretaken. By 1909, three years later, this figure had increased to over 400,000 birds. Again, thiswas a business that essentially involved catching and killing birds. The taxidermy businessseems to have been one of the main industries in the islands in the closing years of the Meiji era.

Stuffed bird specimens

Value of marine products (yen)In these years Koga seems to have started trying to save on waste. The birds’ feathers and skinwere preserved and exported, but this still left the bones and meat of the birds unused. So hestarted to turn this into fertilizer and exported it separately. The oil that was produced during theprocess of making the fertilizer was also exported as machine oil. Ultimately, almost the entire
bird was exported. For the seabirds of the islands the period of Koga’s involvement was adisaster. The albatross went extinct and terns too were taken in huge numbers for processing in
the factory set up on Minamikojima Island.
This photograph shows Minamikojima in the years before the war. In photographs of the time
there are always huge numbers of terns and other seabirds in the flat areas of Minamikojima likethis. But records left by people who visited the islands after the war say that there were no
seabirds to be seen anymore. There was a rapid transformation from a time when the island wasfull of seabirds. During the development years there was a huge reduction in absolute numbers
to such an extent that they probably have not recovered their original population even now.

18

Minamikojima(1900)

But that’s enough about the seabirds for now. Let’s move onto the second category, that is to
say the collection of marine products like shark’s fin, seashells, and turtle shell. It is likely that
Itoman fishermen were already engaged in this kind of activity before the islands were formallyabsorbed into Japanese territory. Koga’s curriculum vitae does not give detailed description ofthis business so the details are unclear but even if Koga did not personally take the lead in
exploiting these marine products it seems likely that the Itoman fishermen he sent to the islands
played a chief role in collecting the products and processing them. If you look at the graph you
can see that although the numbers fluctuate somewhat from year to year there are none of thedramatic increases and decreases we saw on the graphs for the feathers and preserved birds.
Next is the third category, bonito fishing and dried bonito production. This started around 1905.
At first Koga had three bonito fishing boats manufactured in the Japanese main islands andhired several dozen experienced bonito fishermen and dried bonito processers from Miyazaki
Prefecture, since bonito fishing and dried bonito production were not established in Okinawa at
the time and there were few workers available with the necessary skills. He shipped his new
employees to the Senkaku Islands and set them to try their hand at bonito fishing. The results
were positive, but his three boats were destroyed in the strong winds that buffeted Okinawa thatyear. Since the results had been so promising, Koga decided to have another five new boats
made the following year, 1906, and documents suggest that he was “enjoying better results thanever.”
Contemporary newspaper reports give us an idea of the kind of success enjoyed by bonito
fishermen in the Senkaku Islands at the time. One article from the Ryukyu Shimpo dated
December 29, 1905 carried the title “Bonito Fishing in the Prefecture This Year (Part 1).” The
article was written by a man named Goro Tamagusuku, who was a marine products technician
working for the prefecture. The bonito fishery in the Senkaku islands for this year (June to
October) was worth 3,860 yen from two boats, or roughly 1,930 yen per boat.

19

Two years later another article in the Ryukyu Shimpo carried the title “The State of Fishing
Industry in the Prefecture This Year (4): Bonito Fishing, by Goro Tamagusuku.” According tothis article, three bonito fishing boats based in Senkaku brought in around 18,000 yen, or 6,000
yen per boat. This was the third most valuable catch in the prefecture after Motobu and Kerama.
In the Kerama district, 15 boats took 22,500 yen, while in Motobu 22 boats took 36,500 yen. In
both areas the average income per boat was less than 2,000 yen, while in the Senkaku Islands
the average was 6,000 yen per boat. The figures suggest they were catching an almost incredible
amount of fish—so much so that I wonder if the figures are actually correct.
Next, what about dried bonito manufacture? Bonito fishing itself made an impressive amount ofincome, but what about the dried bonito?
For the figures on this, we can look to an article that appeared in the Okinawa Mainichi
Shimbun on October 2, 1910 titled “Values of Inspected Marine Produce,” which records theamount of A-grade dried bonitos inspected from the Senkaku Islands as 2,636 kin. The total
amount of inspected A-grade dried bonito was 5,601 kin for the whole of Okinawa the same
year, so the Senkaku Islands accounted for almost half of the total amount. This shows that bothbonito fishing and the manufacture of dried bonito enjoyed remarkable success in the Senkaku
Islands in these years. Other articles tell us how the dried bonitos were received, in terms of thequality of the products.
According to an article “Dried bonito Spot Sale and Trade Exhibition Fair and Prizewinners”
that appeared in the Okinawa Mainichi Shimbun on May 25 1909, at a sale and evaluation fairheld by the Greater Japan Marine Products Association, dried bonitos submitted by Koga’s
company received a second-class silver award medal and sold for 53 yen and 50 sen per 10
kanme (37.5 kg). I said earlier that his first employees in this business were brought in from
Miyazaki, but he later also brought in some women from Shikoku who were skilled inprocessing Tosa-style bonito flakes (thin flakes of dried bonito) of.
“The number of fishermen on the islands numbers nearly 100. This does not include those
involved in the manufacture of dried bonitos. Several female workers skilled at making
dried fish flakes have also been brought in from Shikoku.” (Ryukyu Shimpo, June 21, 1908
“The Senkaku Islands and Koga Tatsushiro (6), by Rokei”)“Many of the experts producing dried bonitos in Okinawa come from Miyazaki. At firstsome people were hired from Kagoshima and they produced Satsuma-bushi. Then Koga
brought in employees from Kochi who started to produce Kochi-bushi.” (Okinawa Kyoiku,Vol. 53, “Okinawa Prefecture’s Marine Industries,” by Yasohachi Omura, September
1910)

20

Another article comes from slightly later, when dried bonito production had spread to otherparts of Okinawa Prefecture. “This Prefecture and Dried bonito Production (Cont.), by ‘Katsuo
Bushi [translator’s note: The writer’s name is a pen name. Katsuo bushi means “dried bonito” inJapanese.] ’” appeared in the Okinawa Mainichi Shimbun on September 27, 1910. The article
introduced different areas of the prefecture that produced dried bonitos, and in the sectionreferring to Senkaku Islands, it noted that “because specialist workers are employed from themain producing areas of the country, dried bonitos from these islands have excellent quality interms of both form and flavor.”
Regarding the prospects for the Senkaku Islands as a bonito fishing ground and the type offishing grounds that existed around the islands, Koga’s curriculum vitae notes that “Regarding
the prospects of the islands as a bonito fishery, there are two main advantages. First, bait isextremely abundant. And second, schools of bonito come extremely close to the shore, so that it
is not necessary to make long journeys by boat to catch the fish. These conditions make this an
ideal spot for bonito fishing.” The bait referred to here is the bait the fishermen would use tolure the bonito. At the time this could be caught in abundance around the islands. And theschools of bonito came quite close to the shore so it wasn’t necessary to go out far to sea.
According to a serial article entitled “The Senkaku Islands and Tatsushiro Koga (Part 11),” thatappeared in the Ryukyu Shimpo in 1908, it was possible for the fishing boats to make four trips
per day. “In the major bonito fishing grounds of the islands 6,000 to 7,000 bonito can be taken
in a single day, with catches up to 10,000 fish not unheard of.” Ten thousand fish in a single day.
This was huge abundance.
Two main advantages made the Senkaku Islands attractive for fishing: large amounts of bait fish
were available in the local waters, and the fishing grounds were located extremely close to theprocessing center onshore. These factors made it possible to conduct multiple fishing trips in asingle day.
Was Koga the only one at the time to make use of these fishing grounds with such favorable
conditions? One source suggests that Goro Tamagusuku, who turned from a governmentemployed marine products technician to become a bonito fishing operator, caught a huge catchof 16,495 fish at Kuba Island in 1910, according to an article headed “Huge Catch of Bonito” in
the Okinawa Mainichi Shimbun dated October 6 that year. But this is the only source thatrecords anyone but Koga himself fishing in Senkaku. And the fact that Tamagusuku was Koga’s
friend made his situation somewhat different from that of other people.
It seems likely that other people were not in a position to use the fishing grounds.
It was certainly true that the waters around the Senkaku Islands were very good for catching21

bonito, but there were drawbacks too. First, there was the geographical problem. These Senkaku
Islands are isolated in the East China Sea. Access was a serious difficulty in an age when manyboats were still without engines. You also have to consider the freshness of the fish. In thosedays there was no ice-making facility for the fishing industry in Okinawa. Fishermen had tobase themselves in the Senkaku Islands and make trips from there, and then process the fish on
the same island. This condition meant that only limited fishing operators like Koga, who were
granted a lease on the islands, could fish there.
Let’s leave the bonito fisheries for now and turn to a graph showing of the profits and outgoingsof Koga’s businesses on the Senkaku Islands. The bar graph shows the profit or loss for eachyear, while the plotted line shows the cumulative profit or loss overall. As you can see, thebusiness was not always in the black. After the dramatic drop in the numbers of albatross in1900 there were several years where the business made a loss, and the business’s overall profit
dropped into the red. You can see from the graph how the business shows an upturn again after
bonito fishing begins around 1905. It seems that Koga worked tenaciously to develop his
businesses on these uninhabited islands.
Annual profits and cumulative balance

Annual profit(yen)
Cumulative
profit/loss

In a slightly later period after he received his official decoration, Koga’s businesses, including
bonito fishing and his other concerns, stopped expanding and gradually shrank in scale.
The business plans Koga drew up for 1911 detail plans for “Fishing: 20 bonito boats, 20 coralboats.” He had plans for a new business collecting corals. There are also plans for: “3supervisors, 220 fishermen, 100 coral collectors. Seabird taxidermy: 3 supervisors, 150
taxidermists.” In total the plans call for an expansion of the business involving some 470
migrant workers and 40 boats. But in fact the numbers dropped, according to the record
contained in the relevant section of the Survey of the Fishing Industry in the Counties of Miyako
and Yaeyama published two years later in 1913: “In 1913, the company had 2 Japanese-styleboats and 52 employees engaged in fishing.” Rather than growing, the business had actually22

shrunk. “Many of the fishermen are from Yonajiro (perhaps a clerical error for “Yonaguni”)
Island ... but all those engaged in processing and manufacturing are employed from the mainisland of Okinawa.”
It seems that Koga had stopped bringing in workers from Miyazaki and Shikoku by this stage
and was now recruiting his employees from among people living in Okinawa. The scale of thebonito fishing business had shrunk, and the Survey says that the seabird taxidermy business had
also come to an end by then. It seems likely that the tern taxidermy business ended around the
beginning of the Taisho era in 1912. Likely reasons include the fact that several species of tern
were designated protected species (in 1908) and the interruption to exports to Europe caused byWorld War I (1915). By 1914 the dried bonito business and seabird taxidermy were both indecline.
Various source documents from the years that follows seem to record just one or two fishingboats operating in the Senkaku Islands and the scale of the industry in the islands shrank from1912 or so onward. After the death of Tatsushiro Koga in 1918, bonito fishing increasingly
shifted to Ishigaki Island.
7.

After the Decline of Koga’s Business on the Senkaku Islands

As the scale of Koga’s business began to decline in the Senkaku Islands from around 1912,
bonito fishing boats from beyond Okinawa prefecture began to make the trip to these waters.
The most frequent visitors were boats from Taiwan. In 1915 and 1916 bonito fishing boats from
Taiwan expanded their catchment areas to include the Senkaku Islands and began to appear
there in large numbers.
Survey ships from marine research centers in various parts of the Japanese main islands alsobegan to appear, carrying out surveys of the bonito fishing grounds in the seas around Okinawa
and the Senkaku Islands. These included the Kohomaru (Kochi, 1916) and the Shoyomaru(Kagoshima, 1926). Fishing companies from the mainland were now developing larger boats
that would set out to the seas around Okinawa and Senkaku Islands during the fishing season,
knowing that bonito could be caught there in large numbers.
8.

The Emergence of Taiwan

And so fishing boats from outside Okinawa Prefecture gradually began to appear in increasing
numbers. Let’s look at them in turn. Firstly, Taiwan. Originally, it seems that Taiwan had no
tradition similar to the pole-and-line method of bonito fishing known in Japan. They did fish for23

bonito, but generally using nets. These were a slightly different species from those that approachclose to the shore (frigate mackerel and skipjack tuna, preferred for use as dried bonitos), andthey were generally taken with nets.
It therefore seems likely that the bonito fishing business in Taiwan got its real start after Taiwan
came under Japanese administration, and that it was introduced and developed by Japanesefishermen who came to Taiwan from places like Miyazaki and Kyushu.
How did these Taiwanese boats come to the Senkaku Islands?
An article of August 1915 in the Taiwan Nichinichi Shimpo titled “Marine Fishing in Taiwan”
tells us that “today, harbors for fishing boats in the main island of Taiwan exist at Keelung,
Takow, and Tungkang. Given the remarkable success of fishing in Taiwan since the beginningof the Japanese administration, these three ports will surely flourish even more in the future as
centers of the fishing industry. From their base at Keelung, fishing fleets are expanding theirsphere of operations into the waters to the northeast, and in years to come will surely makeexcursions into the waters around the Senkaku Islands and the Sakishima Islands, powered bysteam engines that will replace their petroleum-fueled engines.” The article suggests that fishing
operations of Taiwan should expand their bonito fishing grounds to Senkaku and SakishimaIslands and replace their still-new petroleum-fueled engines with steam engines. The people
involved in the fishing industry in Taiwan at the time could see that as the size of the vessels
increased the day would soon come when they would be able to set out on fishing expeditions toplaces farther afield on the far seas.
Documents from 1916 show that Taiwanese bonito fishing fleets had already expanded to theseas around the Senkaku Islands and were successfully bringing in large catches there. How did
people in Taiwan regard the Senkakus as a bonito fishing ground? In a document titled “Surveyof Seas around Taiwan: Third Report,” the Senkaku Islands are mentioned as a fishing groundin which the catch for a single boat was in excess of 1,500 fish in 1923. Catches in excess of
1,500 fish was recorded 246 times in total, of which the Senkaku Islands accounted for 120
occasions—nearly half the total, especially during the best fishing months from May to July.
The Taiwanese side was fully aware of the excellence of the waters around the Senkaku Islands
as fishing grounds.
Records show that the average weight of bonito caught in the Senkaku Islands was between 4
and 7 kg, and that many of the fish were medium- rather than large-sized. So it seems that
although the fish were there to be caught in huge volumes, they were generally not of the largest
size.

24

9.

Fishing Boats from the Japanese Main Islands

Next, let’s consider the involvement of fishing fleets from the Japanese main islands.
An important part of the context to this development is the appearance of motor engine-driven
boats around the first decade of the twentieth century. These provided a substantial boost tobonito fishing in many parts of Japan. By the late 1910s and into the 1920s, the number offishing boats exceeded the capacity of fishing grounds close to the Japanese shores, and thecapacity of the boats outstripped the ability of the fishing grounds to support them. As a result,fishermen were forced to go farther out on the open sea and to develop new fishing grounds. In
1916, a marine fisheries research center in Kochi Prefecture sent its ship the Kohomaru tosearch the seas surrounding the Seinan Islands stretching from Kagoshima to Okinawa andTaiwan for development of fishing grounds. Records of this survey refer to the Senkaku Islands
as one of the bonito fishing grounds used by Okinawan and Taiwanese fishermen. In a reportfrom 1924, even the fishing grounds around Yaeyama are acknowledged as Taiwanese fishinggrounds, as fishing fleets from Taiwan were so active in that area. “Few boats set out from thelocal islands to the fishing grounds south of Yaeyama, and there are more fishermen from
Taiwan, that this area is often regarded as a Taiwanese fishing ground.”Next, the surveys of fishing grounds carried out by Kagoshima Prefecture. Kagoshima is locateddirectly north of Okinawa, and might be called its next-door neighbor. There was a shortage offishing grounds here too, creating a need to move farther out and try to develop new fishinggrounds. The first step was taken in 1924 by a civilian named Ko Hara who constructed a large
ship called the Chiyomaru that explored the seas around Okinawa in 1925, discovering new
fishing grounds around Taisho Island in the seas off the west coast of Kume Island on the edgeof the continental shelf. Starting the following year, 1926, a marine fisheries research center in
Kagoshima carried out several surveys (from 1926 to 1936) in the bonito fishing grounds
around the Senkaku Islands and along the continental shelf in an attempt to expand their fishinggrounds.
And it was not just bonito. In 1933 there was an experiment at catching hata-uo (a kind ofmarlin) in the same fishing grounds. A typhoon hindered the experiment but the survey reported
seeing large numbers of marlin around the Senkaku Islands and noted that it promised to be an
extremely good area for that species.

25

10. Developments in Okinawa
So far I have been talking about the general trends in the fishing industry outside the prefecture,
but what about movements on the Okinawan side?
One thing that played a large role in the attempts by Taiwan and Kagoshima to expand theirfishing grounds was the large research vessels such as the Ryokaimaru and the Shoyomaru
owned by official research organizations.
It was in around 1921 that the first specialist organizations and research ships were constructedin Okinawa. Subsequently, the prefecture built the research survey vessels Ryukyumaru (1921)
and Tonanmaru (1927). In addition to conducting experiments on various types of marine
produce, these also carried out surveys in the seas adjacent to the Senkaku Islands (1928–1934).
From the mid-1920s on, the Okinawa newspapers carried reports on the latest state of thefishing industry in Taiwan, and we find mentions in reports of the time of “fishing grounds
including the Senkaku Islands and Sekibi-sho.”
We can assume that people in Okinawa knew that the area around the Senkaku Islands
contained large stocks of bonito. Chigaku zasshi [Journal of Geography, Year 46, No. 546],
published in 1934 August, contained an article “Diverse Views of the Geography of the Ryukyu
Islands: Kinoshita Kameki.” This included “A Map of Fishing Grounds in the Seas around
Okinawa” showing the bonito fishing grounds dotting the area stretching from southern
Kagoshima through Amami, Okinawa, Miyako-Yaeyama, and the Senkaku Islands, to Keelung
in Taiwan. People in Okinawa therefore knew that the waters around the Senkaku Islands wereprime fishing grounds for bonito.
But unfortunately I have found no sources that can reveal the extent and frequency with which
civilian fishing boats from Okinawa traveled to the Senkaku Islands. There are no traces of trips
to the Senkaku Islands to fish for bonito. Although they were aware of the fishing grounds there,
it seems the Okinawan bonito boats were too small to make the long journey to get there. They
were not robust enough to withstand the rigors of voyages out on the offshore. Further, there
was a chronic shortage of fish that could be used as bait in the local area. In Okinawa too, there
were quite a few bonito fishing boats by this stage—more than enough compared to the fishinggrounds.
Then there was the problem of the supply of bait fish. These were consumed whether thefishermen successfully caught the bonito or not. This meant that the supply of bait fish would
naturally run out in short order. Improving this situation would have been very difficult indeed.
Okinawa consists of islands surrounded by coral reefs. The fish that live in the reefs are not very

26

robust and did not cope well with long journeys by boat. Within a day or two of being caught,
unfortunately, most of them were dead. Given these facts, it is clear that the necessary
conditions were not yet in place for bonito fishing expeditions from Okinawa.
According to “A Summary of the Okinawa’s Fisheries: Edited by the Economic Department,
Fisheries Divison, Okinawa Prefecture” of 1939, rod-and-line bonito fishing “is carried out on a
day-trip basis, with boats leaving before dawn to supply themselves with bait. Very few boats
use ice when going out on a fishing expedition. The whole day’s traveling and fishing covers an
area of within 50 nautical miles.” So the work was done within the space of a day, and therecords say the traveling was kept to within 50 nautical miles, but as I said at the outset, it is 90
nautical miles to the Senkaku Islands, even from Ishigaki Island.
Taking this into consideration, it becomes clear that the Senkaku Islands were forbiddingly
distant objectives for the bonito boats of Okinawa. Although they knew that the seas there
offered excellent fishing opportunities, it seems unlikely that they ever thought too much ofthese fishing grounds as places they could realistically use themselves.
Hardly any bonito fishing boats went to the Senkakus from Okinawa. But the fishing grounds
for several species of deep-sea fish known as machi esteemed in Okinawa were located along
the edge of the continental shelf. And boats form Okinawa did travel to these grounds.
An article in the Okinawa Nippo of April 13, 1938, notes: “Kakinohana fishery is the only deepsea fishery in the prefecture for tuna, hata-uo, and machi, and at present owns as many as 25
boats engaged in long-line fishing for tuna and rod-and-line fishing for bottom-feeders,traveling from the close to the main island of Okinawa far afield as Miyako, Yaeyama, Taiwan,
and the Senkaku Islands in search of new fishing grounds.” The fishermen of Kakinohana in
Naha would fish for tuna during the summer months and then switch to fishing for machi withrods around the Senkaku Islands in the winter.
To sum up, in the years after the islands were incorporated into Japanese territory in the Meiji
era, the Senkaku Islands were developed as a monopoly by Tatsushiro Koga. From his bases on
Kuba and Uotsuri Islands, Koga built a business gathering albatross feathers, producing stuffedterns and other seabirds, fishing for bonito, and producing dried bonitos. But from around 1912
the scale of these businesses shrank. At the same time, many boats from outside the prefecture
started to visit the islands at this time, larger boats now equipped with engines and refrigeration
facilities on board. Okinawa was slow in developing ice-making facilities for the fishingindustry. Taiwan started to carry ice on its fishing boats from quite an early stage. These seemto be the chief reasons why Taiwan was able to carry out fishing expeditions to the Senkaku
Islands without needing to use the islands as a base.

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From the mid-1920s modernized fishing boats did start to travel to the Senkaku Islands from themain island of Okinawa, mainly to catch deep sea fish known as machi. The fishing grounds
around the Senkaku Islands became recognized for their importance both within and without theprefecture, but as the years passed Japan’s war in China bogged down and an age of restrictions
on supplies began. There were frequent shortages of oil for fishing boats, and the fishingindustry too started to feel the effects of the war.
On January 1, 1940 Zenji Koga, the son who had inherited the Senkaku Islands business fromhis father Tatsushiro, dissolved the company’s office in Yaeyama. However, there are signs that
Seiei Teruya, a former supervisor of the branch, continued to run the Yaeyama branch evenafter it was formally folded up, although the details of this still remain unclear. In December thefollowing year, 1941, the Pacific War began. In March 1945 came the Battle of Okinawa. By
the time of the Battle of Okinawa, fishing on the Senkaku Islands was more or less at an end.
11. By way of an afterword
I have briefly outlined the history of the fishing industry in the Senkaku Islands from the time
before it was incorporated into Japanese territory, after the incorporation and up to the war.
These are a few photographs I have found that give us a glimpse of the islands during thedevelopment years.
This is Kuba Island. This was taken in 1900, probably during the survey I spoke about earlier inwhich Miyajima and Kuroiwa went onshore. Around seven small hut-like structures had alreadybeen built on the island by this stage. The Japanese rising sun flag can be seen, perhaps put up
by the people on the island when they saw the boat coming.

Minamikojima(1900)

Kuba Island(1900)

This is Minamikojima shown the same year. This is the small island I showed you at the start.
Here too you can see little huts and a small stone wall. Visible in the front of the picture is28

presumably a Japanese fishing boat. The two boats further back in the picture are probably thefishing boats belonging to the Itoman fishermen, called sabani. This is presumably the area
where people lived. It’s a neat little area set aside for that.

The bonito processing factory on Uotsuri Island(1908)

The wharf on Uotsuri Island(1908)

This is Uotsuri Island around 1908. Eight years on from the previous picture. This shows an
overall view of Koga’s dried bonito factory when the business was at its height and people werestill producing large quantities of dried bonitos. There are huts lined up in rows and a stone wallat the back to protect them from storms. You can also see a steamship at anchor offshore. This isprobably the Kyuyomaru.
This picture too is from 1908. The wharf you can see here is not a natural feature of the island.
It was made by Koga’s workers, probably by fishermen from Itoman, who were used to working
with dynamite. This is probably a bonito fishing boat; you can see the rods they used. On theright there are some children. I assume you have heard of the word “Itoman-uri.” These children
were probably sold like Itoman-uri and sent to work on the boats. They would have been from
Miyagi or Fukushima Prefectures originally, in the northeastern regions of the Japanese
mainland islands.
If you went to the Senkaku Islands and stood on the very same spot today you would probably

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find it impossible to believe that these scenes ever took place there. It’s an era that’s vanishednow, but it did once happen.
That concludes my remarks what I want to say for today.

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