Population distribution

Tarawa Atoll has a population of 56,284, accounting for more than half of Kiribati’s population of 103,058 (Statistics, 2010). Only 19 of the 59 reef islands are inhabited; this includes all the elongated reef islands as they are larger and therefore provide more space (Table 3.3; Figure 3.14Figure 3.14). The reef islands that are uninhabited are mainly located in the central part of North Tarawa. They are not occupied primarily because they are too small or they are situated close to the reef edge. The distribution of population across the two sections of Tarawa Atoll is unequal, with higher population density in the southern section than that of the northern section. North Tarawa people live on the sheltered, lagoon-facing side of the reef islands away from the trade winds, as is normal for people in Kiribati.

In contrast, people on the southern arm tend to occupy both sides of the reef islands as they are not directly exposed to the northeasterly trade winds. In South Tarawa, population density increases towards the west. Three reef islands, Betio, Bairiki and Nanikai, have population densities ≥60 persons per hectare (Table 3.3, Figure 3.14). These reef islands are the main administration centres for Tarawa Atoll. People who reside on these reef islands live on the remaining land on that is not occupied by Government Infrastructure. Reef islands with population densities <60 but >10 persons per hectare in descending order are as follows Ambo-Teaoraereke (52) and Bonriki-Taborio (23), (Table 3.3, Figure 3.14). In North Tarawa, reef islands with high population densities of ≥5 persons per hectare are Tanaea (34) Buota (17), Nabeina (12), Kainaba (9), Tabonibara (8) Abaokoro (8), Notoue (7) and Abatao (6) (Table 3.3).

83

OCEAN LAGOON

Key: Foraminifera Coral Scale is 1mm

Molluscs

Figure 3.13. Sediment composition of selected ocean and lagoon beach locations. A: Tabiteuea ocean, B: Buota lagoon channel, C: Notoue ocean, D: Notoue lagoon, E: Teaoraereke ocean and F: Teaoraereke lagoon. Note that foraminifera are abundant and present in all photos indicating their importance to reef island sediment composition. Corals are next in abundance whilst molluscs are of minority proportion.

Some of these places are close to South Tarawa (Buota and Abatao), where access is available by causeways, bridges, or even by canoes. Abaokoro is the administration

A B

C D

84 centre of North Tarawa hosting the hospital, government and secondary schools. Reef islands located in North Tarawa with population densities <5 persons per hectare are Tabiteuea (5), Nuatabu (3), Buariki (3), Marenanuka (1), Taratai (1) and Tebangaroi (1) (Table 3.3, Figure 3.14). The smaller reef islands located in the central part of North Tarawa are uninhabited.

Figure 3.14. Population density (persons per ha) distribution across reef islands of Tarawa Atoll. Distribution of population is unequal with a greater population density in South Tarawa. Buariki North Tarawa South Tarawa Buariki Taratai Notoue Betio Marenanuka Tabiteuea Bonriki-Taborio Ambo-Teaoraereke Bairiki Nanikai Nuatabu Abaokoro Tebangaroi Tabonibara Nabeina Tanaea Buota Abatao Kainaba

85 New residents to North Tarawa are mainly retired Government workers who do not wish to return to the outer reef islands. In the case of Tabiteuea, many residents are people who are still working but prefer to live in a rural setting and commute to work on Bairiki, Betio or Bonriki-Taborio by sea. This suggests that there is internal migration from South Tarawa to North Tarawa due to issues of living space.

Population increase has led to issues of overcrowding. This has forced people residing in Betio, Bairiki, Nanikai and Bonriki-Taborio reef islands to live in vulnerable areas such as on dynamic sand spits, active beach berms and in low lying areas. In North Tarawa, with low population densities, space is not an issue so people do not reside on newly accreted areas as the locals understand that they are dynamic. Locals tend to develop these areas by planting coconut trees to stablise the mobile sand.

Space becomes a serious issue in South Tarawa with the growing population, as more local residents encroach onto the dynamic beach. As assets are placed close to the active beach berm, the risk from high tides and storm events increases, and eventually leads to the construction of a coastal structure. These structures serve two purposes: the first is to protect the assets at risk, and the second is to reclaim more land to address the space pressure. Individuals and religious groups have constructed reclamations of varying sizes, shapes and designs around South Tarawa. These developments make the shorelines appear abnormally straight with 90o corners when viewed on aerial photos (Figure 3.10B).

In order to build a coastal structure, approval from the Lands and Foreshore Committee (LFC) responsible for these areas is required. In addition, approval also needs to be obtained from the Environment Division in line with the recent Environment Act. However, as was noted in an inventory survey carried out by the Lands Management Division in 2000, this is not normally done. Many seawalls and reclamations have been erected without prior approval from the LFC.

The LFC generally approves seawall applications of I-Kiribati people wishing to construct a seawall for the purpose of protecting assets; however, the committee does

86 not usually approve reclamations as they are extensions of land, and disrupt longshore sediment transport. Therefore when most applications for seawalls are approved, they are built as reclamations (Figure 3.15 B). Examples of approved reclamation applications are those built in front of mangroves on the lagoon side as these appear to have a minimal detrimental impact on the sediment transport (Figure 3.15G). Most of these structures lack engineering design and are generally vertical. A large proportion of these structures are temporary as shown in Figure 3.15 (A, C, D, E, F, G and H). These structures are frequently built from logs, coral boulders, and cement bricks backfilled with rubbish, sand or a mixture of both. Others appear more permanent with cement added to bind the structure.

Figure 3.15 illustrates the various types of seawall designs that are present throughout South Tarawa. A significant proportion of these coastal structures depend on construction material sourced locally from the surrounding reefs and beaches such as coral rocks, conglomerate, gravel and sand. This contributes to the removal of material from beaches (see Section 3.6.1). Most of these developments are owned by individuals, whilst some are public structures created by religious groups, schools or the Government. Engineer designed structures such as jetties, ports and causeways are Government assets.