Survey of Maekata Bay 2004-2006 | アジア水中考古学研究所

Survey of Maekata Bay 2004-2006

Introduction

The geographical environment of the Ojika Island has had historical characteristics in the Goto archipelago since ancient times. Many archaeological data that have come to light in the long history of Ojika Island can help Ojika history in moredetail. In addition to these data, important archaeological data have been offered from the sea around Ojika Island. The Ojika-cho board of education has been aware of underwater sea around Ojika Island to understand in more detail the abundance and formation of the archaeological remains or ruins on the Island, and they carried out the first survey at Yamami-oki Underwater Site facing the north entrance of Maekata Bay in 2002 and found artifacts in distributed area of the seabed. As the result, many Thai earthen ware jars with four handles on the shoulder, dated to the last quarter of the 16th century through the early 17th century have been found. Moreover, existence of potable oven of the Southeast Asia indicates the possibility of shipwreck in this area. After the first campaign, the underwater archaeological surveys by the Ojika-cho board of education carried out at Maekata Bay and the adjacent area in 2004 through 2006.

1. 2004 Season Campaign

The first campaign of 2004, title called the underwater survey of Maekata Bay and the adjacent area carried out. Aim of the survey is whether archaeological objects are found at Maekata Bay and adjacent, and if found, these artifacts should be documented.

At Maekata Bay Stone anchor stocks (Ojika No.1 and No.2) were found off the Kojima shrine in the late Taisho and the early Showa eras and Ojika No.1 was recovered at that time but Ojika No.2 was still on the sea bottom. Another anchor stock (Ojika No.6) found on the sea bottom off Karamizaki Point was recovered in 1985. Moreover, a Chinese brown glazed-small jar was found beneath the fish nurseries off Kusukuri Point and recovered. These artifacts may indicate a rich underwater site or sits belonging to medieval times and for this reason. Maekata Bay should be a primary area to survey with scuba diving.

As the result of the survey Chinese ceramics and brown glazed wares, Japanese ceramic, and stone anchor stocks (domestic and Chinese types) were found off Kusukuri Point.

Objects found in the 2004 Season Campaign

Anchor Stocks

There are two types of stone anchor stocks found at Maekata Bay; one is Chinese type, and the other is domestic type.　

Chinese Stone Anchor Stocks:

Ojika Nos.7 and 8 were found at the south of the No. 5 site (33°12′191″N、129°05′964″E) and recovered.

No.7 is broken in half and has no sign of groves on the center portion. It is 87cm long and 17cm×11cm thick at the end. The center portion is 26.5cm×16cm thick. This anchor stock belongs to so-called Matsuoka’s type A-1.

No.8 is only survived by the end portion. It is 34cm long and 13cm×7.5cm thick at the end. The broken portion is 26.5cm×10.5cm thick. This stock belongs to Matsuoka’s type A-1.

Ojika Nos.11 and 12 were found at the edge of row of rocks as the No.6 site (33°12′229″N、129°05′467″E). These two anchor stocks were not recovered due to establishment of datum points.

No.11 is broken in half and has no sign of groves on the center portion. It is 120cm long and 20cm×18cm thick at the end. The center portion is 25cm×28cm thick. This anchor stock belongs to Matsuoka’s type A-1.

No.12 is broken in half and has no sign of groves on the center portion. It is 102cm long and 15cm×14cm thick at the end. The center portion is 25cm×20cm thick. This anchor stock belongs to Matsuoka’s type A-1.

Ojika Nos.9 and 10, which are located at 33°12′107″N,129°05′867″E, were found in five meters apart at the site east of Akamaru Shallows.

No.9 is broken in half and has clear sign of groves on the center portion. It is 133cm long and 26cm×17cm thick at the end. The center portion is 35cm×24cm thick. This anchor stock belongs to Matsuoka’s type A-1.

No.10 is broken in half and has clear sign of groves on the center portion. It is 125cm long and 25cm×18cm thick at the end. The center portion is 35cm×24cm thick. This anchor stock belongs to Matsuoka’s type A-1. No.9 and No.10 are originally belonging to a single stock but broken in half at the center portion.

Domesstic Stone Anchor Stocks:

Ojika domestic type Nos.1 and 2 are the small proto type of anchor stock. They were found near the No. 5 site.

No.1 is a squared column type anchor stock. Its size was not measured.

No.2 is broken in half. It is 65cm long and 11.9cm×9cm thick at the end. The broken portion is 13cm×11.5cm thick. These two anchor stock belong to the early modern times. No.2 was recovered.

Pottery

　There are three pottery found at Maekata Bay; two are Chinese ceramics, and the other is domestic ceramic.

Chinese Ceramics:

X-1 is a brown glazed small jar, which had been found on the seabed beneath the fish nurseries before 2004 campaign season. It is 19.2cm high, and the mouth is 6.0cm in diameter and the base is 6.2cm in diameter. The surface shows strong touch of fingers spirally revolving upward by a pottery wheel. The upper part has the smooth surface by fingers, and the surface of the lower part has been smoothly executed by a spatula.

X-2 is a blue celadon bowl (Lung quan ware type), which was found near the anchor stock (Ojika No.11). It is 7.2cm high and 16.4cm in diameter for the mouth, and 5.8cm in diameter for the ring base. The surface was curved with design of lotus petals, and the bottom of inside was curved with floral design.

X-3 is a white porcelain bowls, which was found near the anchor stock (Ojika No.12). It is 6.9cm high and 17.1cm in diameter for the mouth, and 8.0cm in diameter for the base. The lower part of the surface is unglazed..

Domestic Ceramic:

X-4 is blue and white deep bowl belonging to a contemporary product found at edge of rows of rocks starching from Kusukuri Point.

2. 2005 Season Campaign

Surveys of underwater sites at Maekata Bay and adjacent area in 2005 season campaign carried out at seabed off Kusukuri Point located in the northern area of Maekata Bay, where stone anchor stocks and Chinese ceramics were intensively found in the last season. The purpose of the 2005 season was to understand the distribution and context of the objects and to make a distribution map as correctly as possible. Survey started at first to establish a temporary datum point on the end of the Chinese stone anchor stock (Ojika No.12) at method was Therefore, the end of the stone anchor stock (Ojika No. 12) found on the seabed off Kusukuri Point. The other anchor stock (Ojika No.12) is two meters apart from Ojika No.11. Ojika No.12 is located at latitude of 33°12' 229″N and longitude of 129°05' 467" E. We have learned many objects, which were found near the datum point, distributing to same extent on the seabed from northwest to east of the shallows extending from Kusukuri Point; therefore, the measure ropes were extended 50m from the datum point at 15°, 40°, 60°, 90°, 115°, 240°, 315°, and 345°, and swim line search was conducted the along the line and in the area of either side of the line. The objects found on the seabed were measured by the triangle method. These objects are thirty four including Chinese ceramics and brown glazed wares, domestic wares, stone anchor stocks, and contemporary Japanese wares. These were found in about 8 through12m deep. On the seabed of the south of Maekata Bay two domestic anchor stocks were identified within 10m deep.

The objects recorded on the seabed were recovered to examine the style and age. Moreover, the seabed at the southern area of Maekata Bay, the adjacent area where two Chinese recovered stone anchor stocks (Ojika Nos.3 and 4) were found at Hadaka Shallows of Noh Island in 1947 and 1948, and the area where a stone anchor stock has been seen at Kamiuradashi Shallows off Tonozaki-hama Point were chosen to understand the distribution and existence of objects. In this season researchers of the Woori Research Institute of Cultural Properties, South Korea joined the survey, and ROV developed by Sasebo National Collage of Technology participated for test run.

Objects found in the 2005 Season Campaign

Anchor Stocks

There are one Chinese type and four domestic type of anchor stocks found at Maekata Bay; two domestic stone anchor stocks (Ojika domestic type Nos. 5 and 6) were found at the west side of Oone-se Shallows, locating at the southern area of Maekata Bay. The other two anchor stocks (Ojika domestic type Nos.3 and 4) were found at the edge of rows of rocks stretching from Kusukuri Point, and one Chinese anchor stock was found at the same area.

Chinese Stone Anchor Stocks:

Ojika No.13 was found near the line set at 90 degree from magnetic north and broken in half. The survivaled portion is 96cm long and 18cm×11cm thick at the end. The broken area is 28cm wide. This anchor stock belongs to Matsuoka’s type A-1, and it is still on the seabed.

Domestic Anchor Stocks:

Ojika domestic type No.3 was found near the line set at 60 degree from magnetic north. This rectangular column shaped small anchor stock is complete in shape and 100cm long, 15cm wide, and 10cm thick. This specimen is still on the seabed.

Ojika domestic type No.4 was found near the line set at 60 degree from magnetic north. This anchor stock is similar shape as No.3 and complete in shape. It is 119cm long, 12cm×11cm at the end, and 15cm×10cm for the opposite end, and the widest portion is 16cm×10cm. This anchor stock was recovered.

Ojika domestic type Nos.5 and 6 are rectangular column shaped small anchor stock. Their sizes are not measured and still on the seabed.

Pottery

There are thirty five including Chinese and domestic pottery. Chinese pottery can be mainly classified with blue celadon bowls and dish, white porcelain bowls, and brown glazed jars. Domestic pottery are divided into the products of two periods; one is medieval times, and the other is belonging to contemporary age.

Chinese Ceramics:

C-4 was found near the line set at 60 degree from magnetic north. This is a Tongan ware type blue celadon dish. It is 2.2cm high, 10.1cm in diameter for the mouth, and the base is 4.95cm in diameter. Inside is exsecuted with floral design and sizzag pattern by a comb.

C-8 was found near the line set at 90 degree from magnetic north. This is a Tongan ware type blue celadon bowl. It is 6.8cm high, 16.3cm in diameter for the mouth, and the ring base is 5.4cm in diameter. Outer surface is covered by cobm pattern, and inside is executed with floral design and sizzag pattern by a comb.

C-10 was found near the line set at 240 degree from magnetic north. This is a Lung quan ware type blue celadon bowl. It is 7.25cm high, 17.0cm in diameter for the mouth, and the ring base is 6.9cm in diameter. Inside bottom is executed with stamped Chinese characters ”金玉満堂”.

C-2 was found near the line set at 40 degree from magnetic north. This is a Lung quan ware type blue celadon bowl. It is 7.2cm high, 16.6cm in diameter for the mouth, and the ring base is 5.7cm in diameter. Inside is curved with lotus design, and floral design at the bottom.

C-13 was found near the line set at 115 degree from magnetic north. This is a Lung quan ware type blue celadon bowl. It is 7.4cm high, 16.4cm in diameter for the mouth, and the ring base is 6.2cm in diameter. Inside is curved with lotus design, and floral design at the bottom.

B-5 was found near the line set at 345 degree from magnetic north. This is a Lung quan ware type blue celadon bowl. It is 7.6cm high, 16.8cm in diameter for the mouth, and the ring base is 5.9cm in diameter. Exterior is curved with lotus design.

A-3 was found near the line set at 15 degree from magnetic north. This is a Lung quan ware type blue celadon bowl. It is 6.95cm high, 16.2cm in diameter for the mouth, and the ring base is 6.4cm in diameter. Interior is divided into five spaces by double lines, and floral design is curved inside the spaces.

A-4 was found near the line set at 15 degree from magnetic north. This is a Lung quan ware type blue celadon bowl with trefoil mouth It is 7.1cm high, 16.9cm in diameter for the mouth, and the ring base is 6.0cm in diameter. Interior is divided into four spaces by double lines, and floral design is curved inside the spaces and at the bottom.

C-7 was found near the line set at 90 degree from magnetic north. This is a Lung quan ware type blue celadon bowl. The survived height is 3.8cm high, 16.9cm in diameter for the mouth. Interior is divided and curved with floral design.

A-2 was found near the line set at 15 degree from magnetic north. This is a white porcelain shallow bowl. It is 5.3cm high, 12.9cm in diameter for the mouth, and the base is 4.9cm in diameter. Exterior is curved with lotus and comb design. Interior is divided into four spaces by double lines, and each space is executed by a comb.

C-12 was found near the line set at 240 degree from magnetic north. This is a white porcelain bowl. The survived height is 3.75cm, and the base is 5.9cm in diameter. Surface has no design.

C-11 was found near the line set at 240 degree from magnetic north. This is a white porcelain bowl. It is 6.6cm high, 18.2cm in diameter for the mouth, and the base is 6.1cm in diameter. Interior is curved with rough floral design. The mouth might have been trefoil in shape.

A-7 was found near the line set at 15 degree from magnetic north. This is a white porcelain bowl with unglazed mouth. The survived height is 3.0cm, and the base is 5.8cm in diameter.

A-14 was found near the line set at 90 degree from magnetic north. This is a white porcelain bowl. The survived height is 3.6cm, and the mouth is 16.2cm in diameter. Glaze on the either surface of the mouth is wiped out in narrow band.

A-1was found near the line set at 15 degree from magnetic north. This is a Wu xing ware type brown glazed jar with long body and four lug handles on the shoulder. The survived height is 12.4cm, and the mouth is 8.2cm through 9.3cm in diameter.

C-9 was found near the line set at 90 degree from magnetic north. This is a Wu xing ware type brown glazed jar with long body and four lug handles on the shoulder. The survived height is 12.8cm, and the base is 8.2cm in diameter.

C-1 was found near the line set at 40 degree from magnetic north. This is a Wu xing ware type brown glazed jar with long body and four lug handles on the shoulder. The survived height is 12.1cm.

B-1 was found near the line set at 315 degree from magnetic north. This is a brown glazed small dish. It is 3.35cm high, 11.0cm in diameter for the mouth, and the base is 3.5cm in diameter. I

A-6 was found near the line set at 15 degree from magnetic north. This is a brown glazed jar. The survived height is 25.7cm, and the mouth is 28.2cm in diameter. Exterior is executed by parallel grooved pattern, and interior is executed by compass grooved pattern

A-9 and A-11 Two shards belong to the same jar and were found near the line set at 60 degree from magnetic north, and two pieces were found 4.8m apart on the seabed. This is a brown glazed jar with four lug handles on the shoulder. The survived height is 13.7cm, and the mouth is 13.0cm in diameter.

A-12 was found near the line set at 60 degree from magnetic north. This is a brown glazed jar. The survived height is 9.9cm. This type of jar would have four lug handles on the shoulder .

A-5 was found near the line set at 15 degree from magnetic north. This is a brown glazed jar. The survived height is 14.5cm. This type of jar would have four lug handles on the shoulder.

Domestic Earthen Ware:
Haji Ware

A-8 was found near the line set at 15 degree from magnetic north. This is a coarse plate. The survived height is 2.2 cm, and the mouth is 9.0cm in diameter. The base has a concentric line marked when separated from the turning pottery wheel by a string.

B-6 was found near the line set at 345 degree from magnetic north. This is a coarse plate. It is 2.65 cm high, and the mouth is 14.8cm in diameter. The base is slightly concaved and has a concentric line marked when separated from the turning pottery wheel by a string, and stamped annual rings of the wooden plate ware left on the concentric line.

C-3 was found near the line set at 60 degree from magnetic north. This is a coarse plate. It is 2.2cm high, and the mouth is16.0cm in diameter. The base has a concentric line marked when separated from the turning pottery wheel by a string, and stamped annual rings of the wooden plate ware left on the concentric line.

Sue Ware

A-13 was found near the line set at 60 degree from magnetic north. This is a relatively deep bowl and the fabric is to same extent good. The survived height is 7.2cm, and the base is slightly concaved and 9.3cm in diameter. The base has a concentric line marked when separated from the turning pottery wheel by a string.

3. 2006 Season Campaign

The purposes of the underwater survey in the 2006 season were to search archaeological remains and to make the distribution map of the objects found on the seabed off Kusukuri Point. As the result of the survey, thirty four Chinese ceramics and domestic pottery including stone anchor stocks were found within the limits with a radius of fifty meters between fifty meters of northwest and south-southeast from the Chinese anchor stock (Ojika No.12), and these objects were found on sandy mad layer or in half submerged condition; we have learned that the sandy mad layer accumulates thin on the layer of stones and rocks in this area. For this reason, it could be assumed that the intensively distributed objects were buried in the sandy mad layer deeply accumulated at the southerly area.

Moreover, it was thought that the hull of the sunken ship relating to the already unearthed objects might be discovered in the sandy mad layer. In stead of the swim searches conducted in the 2004 and 2005 seasons, the survey of this season carried out for conducting the first trial trench excavation to use the dredge at Maekata Bay. The other assignment of this season was to measure the altitude of seabed at Kusukuri Point and also examine the topography of seabed, and the benchmarks were set on the quays of Chikaura Harbor and Karamisaki Harbor. It measures 3.5m high as the standard altitude at Maekata Bay.

We had re-investigation of the Chinese typed stone anchor stock (Ojika Nos.9 and 10) at Akamaru Shallows and surveyed at the shallow seabed off the north of Nozaki Island locating east of Maekata Bay; It is said that this area had been used for the religious ceremony from ancient times. No artifact has been found due to the limited diving time.

Objects found in the 2006 Season Campaign

Anchor Stocks

Chinese Stone Anchor Stocks:

Ojika No.14 was found on the seabed beneath the fish nurseries off Kusukuri Point. It is 175cm long, and17cm wide at one end and 19cm wide for another end. This anchor stock belongs to Matsuoka’s type A-1. This specimen is still on the seabed, and lower portion of the body is submerged in the sandy mad.

Pottery

Twenty pottery were found in this season; nineteen are Chinese pottery, and one is domestic pottery. Chinese pottery can be classified with blue celadon, white porcelain, and brown glazed earthen ware.

Chinese Ceramics：

D-6 was found near the line set at 325 degree from magnetic north. This is a white porcelain bowl. The survived height is 5.9cm, and the base is 6.1cm in diameter. The lower part of the body of the outer surface is smoothed by a spatula, and the inside body and bottom are executed by a comb.

D-11 was found near the line set at 48 degree from magnetic north. This is a white porcelain bowl. It is 7.1cm high, 18.3cm in diameter for the mouth, and the base is 6.15cm in diameter. Exterior is smoothed by a spatula, and the inside body and bottom are executed by a comb.

D-7 was found near the line set at 338 degree from magnetic north. This is a white porcelain bowl. It is 7.0cm high, 17.6cm in diameter for the mouth, and the base is 6.0cm in diameter. Inside mouth and lower part of the body are executed by a grooved line surrounded.

D-1 was found near the line set at 90 degree from magnetic north. This is a Tang an ware type blue celadon bowl. The survived height is 6.9cm, and the mouth is 16.8cm in diameter. The lip turns strongly outward.

D-5 was found near the line set at 90 degree from magnetic north. This is a Tang an ware type blue celadon bowl. It is 7.9cm high, 16.4cm through 17.0cm in diameter for the mouth, and the base is 6.4cm in diameter. The lip turns strongly outward. Exterior is executed by thick grooves.

D-10 was found near the line set at 35 degree from magnetic north. This is a Lung quan ware type blue celadon bowl. The survived height is 5.2cm, and the mouth is 15.8cm in diameter. Exterior is executed by carved lotus design.

D-2 was found near the line set at 90 degree from magnetic north. This is a Lung quan ware type blue celadon bowl. The survived height is 5.4cm, and the base is 6.3cm in diameter. Interior is executed by two sets of palmate.

D-4 was found near the line set at 140 degree from magnetic north. This is a Lung quan ware type blue celadon bowl. It is 6.85cm high, 15.65cm in diameter for the mouth, and the base is 6.0cm in diameter. Interior is divided into five spaces by grooves and each space is executed by floral design grooved.

D-3 was found near the line set at 180 degree from magnetic north. This is a Min jiang ware type unglazed small jar with long body. The survived height is 16.1cm, and the base is 6.1cm in diameter. Interior is executed by fingers while running the pottery wheel.

D-9 was found near the line set at 90 degree from magnetic north. This is a brown glazed jar with long body and nearly complete in shape. It is 26.4cm high, 7.1cm in diameter for the mouth, and the base is 7.5cm through 7.8cm in diameter.

P-1 and P-4 belong to the same jar; they were unearthed in the Trench No.1. This is a brown glazed jar with four horizontal handles on the shoulder. The survived height is 9.6cm, and the mouth is 11.6cm in diameter.

P-2 was unearthed in the Trench No.1. This is white porcelain bowl with raised round lip outward. The survived height is 4.75cm, and the mouth is 16.7cm in diameter.

P-5 was unearthed in the Trench No.1. This is white porcelain dish with trefoil mouth. It is 2.05cm through 2.25cm high, 10.2cm in diameter for the mouth, and the base is 3.6cm in diameter.

P-3 was unearthed in the Trench No.1. This is a white porcelain shard; it is difficult to identified whether bowl or dish.

P-1 was unearthed in the Trench No.2. This is a Lung quan ware type blue celadon bowl. The survived height is 6.9cm, and the mouth is 17.0cm in diameter. Interior is executed by carved palmate design.

P-2 and P-4 belong to the same jar; they were unearthed in the Trench No.2. This is a brown glazed jar with four handles on the shoulder. The survived height is 8.7cm, and the mouth is 10.9cm in diameter. A wavy grooved line is running around the shoulder just below the handles.

P-3 was unearthed in the Trench No2. This is a brown glazed jar with four handles. The survived height is 7.6cm, and the mouth is 9.9cm in diameter. A wavy grooved line is running around the shoulder. This specimen may belong to P-2 and P-4 fragments.

Domestic Earthen Wares:
Haji Ware

D-8 was found near the line set at 170 degree from magnetic north. This is a coarse jar. The survived height is 8.4cm, and the mouth is 17.0cm in diameter.

Conclusion

As to the distribution surveys at Maekata Bay and underwater sites at the adjacent areas area, the surveys were conducted in three seasons of 2004 through 2006. Under the geographical and historical environment, unearthed objects have proved that the medieval Ojika island could help to interconnect between the China continent and the mainland of Japan by the ship. Yamami Underwater Site facing the northern entrance of Maekata Bay was surveyed in 2002 and has shown a close relationship between Southeast Asia and Japan; the cargoes from Southeast Asia, especially brown glazed jars with four handles on the shoulder were originally fired in Thailand. These jars have found in large quantity comparing with other cargos. Although there are Chinese ceramics and Hizen wares, etc. as the cargos, there is little in quantity. These objects can be divided intro two periods; one group belongs to the second half of the 16th century through the early 17th century, and the other group can be dated to after the 19th century.

Due to a large quantity of Thai Jars, the stemmed mortars for grinding the spices, called “khrok “ in Thailand, and the portable kitchen ovens, Yamami Underwater Site can fully expect the possibility of shipwreck, but bricks currently counted more than one hundreds at Takashima Underwater Site have not been unearthed at Yamami Underwater Site. As for this fact, People onboard the sunken ship do not use the bricks for hearth but use the portable kitchen oven for cooking meals. In short, the nationality of the sunken ship might have been people having the custom to use the portable kitchen ovens onboard. Furthermore, Thai Jars were not used as the product, but the content of the container was traded. As for the characteristic of the underwater site, the trade ship sunken at Yamami seems to be a Southeast Asian type vessel which Southeast Asian people were onboard. Despite that, these Southeast Asian objects have not been found at the sites of Ojika Island. There is a strong possibility that contents of jars seem to have been dealed in commodities on Ojika Island. However, the products of the Southeast Asia such as pottery would not be dealed as trade goods on this island. It cannot be overemphasized that Yamami Underwater Site is an important site, which show trade and exchange from the Southeast Asia. In the future, synthetic fully investigation for the site will be needed.

The objects found at Maekata Bay are anchor stocks, ceramic, and earthen wares, etc. Most of them belong to medieval times, and these objects have been found more intensively in the northern area than the other areas of Maekata Bay. This situation not only originates in the geography environment of Maekata Bay, but also is considered that the ruins of the circumference on land are relevant. Then, if looking at medieval important ruins, Mt. Honjo’s stronghold and the Zeze’s stronghold are located near Maekata Bay. The former is considered to be the stronghold related to the Matsuura clan despite no ceramics and earthen wares have been found, and at the 　latter the Korean ceramics of the 14-15th century and the Chinese ceramics of the 16th century have been unearthed. It is naturally considered that these two important medieval ruins could use Maekata Bay for the exchange with overseas as an anchorage or a transit trade harbor. In fact, medieval sites found accompanied with the Chinese ceramics among the Goto archipelago heavily concentrates on Ojika Island

However, the domestic earthen wares and the Chinese ceramics, which were found by the surveys off Kusukuri Point, belong to the 12th through 13th century. There is a time difference from the objects having been excavated in two strongholds. Moreover, neither the Korean ceramics nor the 16th century ceramic have been yet found on the seabed. Therefore, the context of the objects found at the bottom off Kusukuri Point needs to look more closely a relation with the medieval ruins on Ojika Island.

As for the underwater survey at the adjacent area, archaeological survey was carried out at Yamami Underwater Site in 2002 for the first time on Ojika Island. Since then, another surveys, such as three-year consecutive surveys of the 2004 through 2006 seasons have been token place at Maekata Bay. These surveys have had important results for Ojika Island, especially stone anchor stocks have been found at Maekata Bay and the adjacent areas; fourteen anchor stocks have been identified on the seabed, and eight samples are the Chinese type, and six are the domestic type. The number will definitely increase in the future, because at least five samples have been till intact on the seabed around Ojika Island. These anchor stocks may help finding shipwreck sites at Maekata Bay or the adjacent areas of Ojika Island.