uninterrupted, across the lagoon. This promotes their 60-80% 

 cover of scrub or forest. Ana-Ana, the southernmost, was 

 periodically occupied from 1987-1991 by the Falconer family. 



Of particular botanical interest are the interior forests, 

 composed of Pisonia mixed with more Cordia than elsewhere 

 on the atoll. Pure Cordia groves (mostly too small to map 

 accurately) typically occupy the forest periphery. 



Their history (apart from the last 3 years) is unknown; all 

 appear to harbor virgin plant communities with occasional 

 drift-derived Cocos or Pandanus. 



35. MOTU RAURAU "Blue- ? ra\ Nodd\ Islet" (3.48 ha) 

 (Figs. 29,57; Pis. 14,78,79) 



Northernmost of the Southern Leeward Islets, we named 

 this motu for the blue-gray noddies {raurau in Gilbertese) 

 observed there. A highly territorial blue-gray noddy was acting 

 as though a nest was nearby. 



Physiography : Raurau is ovoid, with a small lagoonside 

 bay. and maximum dimensions of 1 80 m long and 23 1 m wide. 

 It has the most expansive rubble of all the Southern Leeward 

 Islets. This coarse coral clinker extends, apronlike, around the 

 islet, widest (40 m) closest to the lagoon and narrowest (10 m) 

 to seaward. The seaward reef flats extend 446 m to the ocean. 



Vegetation : The number of plant species is 10(5 trees. 

 1 shrub. 4 herbs), 37% of the atoll's flora. Raurau's two plant 

 communities are simple: a very scant herb mat is sprinkled 

 with Tournefortia, which rises to 6-m-high scrub all around the 

 islet. Laportea forms a narrow band at the interface between 

 coral rubble and scrub. Centrally a Pisonia forest (to 13 m). 

 dotted with Cordia on the periphery, harbors much Morinda in 

 the understory. including the tallest Morinda ( 1 3 m) seen on the 

 atoll. A handful of drift-derived Cocos and Pandanus. the only 

 introductions, dot the scrub. 



Birds : No seabirds were found on transect, but a perimeter 

 walk in 1 988 revealed that tour species bred on the west side in 

 the Tournefortia scrub: red-footed booby (10 pairs), great 

 frigatebird (31 pairs), brown noddy (1 pair), and white tern 

 ( 2 pairs). This islet, for its size, is particularly rich in frigatebirds. 



Comments : Polynesian rats are present. 



36. MOTU EITEI "Frigatebird Islet " (1.41 ha) (Figs. 29.57; 

 Pis. 14.78) 



Second in line from the north, we named this motu for its 

 nesting great frigatebirds, eitei in Gilbertese. 



Physiography : Motu Eitei is fat-elliptical. 105 m long and 

 2X0 m wide. Lying perpendicular to the reef axis, it touches the 

 lagoon edge on its inner side. To seaward, the reel' Hats are 

 644 m wide. 



Vegetation : There are eight species of plants (three trees, 

 one shrub, lour herbs), $09i of the atoll's flora, with no 

 introductions. Eitei is carpeted with three plant communities 

 in the usual concentric arrangement. However, there is a slight 

 difference in the species composition of the herb mats: on 

 transect, the southern mat (2 m wide) consisted solely of 

 Portulaca, while the north side contained a 3-m swath of 

 Heliotropium, Laportea. and scattered Suriana. Inside the mat 



is a ring of Tournefortia scrub (to 5 m) and a central Pisonia- 

 Cordia forest (to 11m). Laportea is particularly abundant, 

 while Portulaca, normally confined to the edges, abounds in 

 small openings within the interior woodlands. 



Birds : Four species of seabirds bred on Motu Eitei in 1988: 

 red-footed booby ( 1 7 pairs), great frigatebird ( 1 4 pairs ). brown 

 noddy (6 pairs), and white tern ( 18 pairs). The first blue-gray 

 noddy nest for Caroline was found in summer. 1990 

 (Subchapter 1.2. this volume). 



37. PISONIA ISLET (2.45 ha) (Figs. 29.57: Pis. 14.78) 



We named this motu for its fine Pisonia forest. 



Physiography : Pisonia, third in the chain from the north, 

 is almost circular and lies closely appressed to its neighbor 

 islets. Its maximum dimensions are 140 m long and 220 m 

 wide. Like Raurau. it possesses a wide "apron" of coral rubble 

 and sparse herbs on the lagoon side. Its seaward reef flats are 

 300 m wide. 



Vegetation : The number of plant species is 15 (5 trees. 

 2 shrubs, 8 herbs), 56% of the atoll's flora. The only introduction 

 is Cocos { few, scattered, north and south shores). Well wooded. 

 Pisonia harbors the customary three plant communities: the 

 herb mat is almost pure Heliotropium, dotted with Suriana. 

 One specimen of Lepidium bidentatum w as found in 1 990. The 

 Tournefortia scrub and forest, covering half of the motu's 

 length and width, grows to 9 m. while the Pisonia— Cordia 

 forest, covering 0.86 ha ( 35% of the islet's area), reached 1 m. 



Birds : Despite the beautiful Pisonia forest, no black or 

 brown noddies nested. Only three species of seabirds bred in 

 1988: red-footed booby (26 pairs), great frigatebird! 14 pairs). 

 and white tern ( 10 pairs). Best represented were red-footed 

 boobies: a perimeter count yielded 18 tended nests, all in 

 Tournefortia scrub. A long-tailed cuckoo was heard in the 

 interior. 



Comments : Rats were common: six were noted on a mid- 

 morning transect survey. 



38. MOTU KIMOA "Rat Islet" (1.80 ha) (Figs. 29.57: 

 Pis. 14.78,80) 



Fourth from the north, we named this motu for its single 

 mammalian inhabitant, the Polynesian rat, kimoa in Gilbertese. 



Physiography : Kimoa, smallest of the Southern Leeward 

 Islets and shaped like a flared teardrop, is squeezed between its 

 neighbor motus. Its maximum dimensions are 92 m long and 

 218 m wide, almost four times the size mapped by Arundel 

 (Fig. 4). The southeast rubble and herb mats are wide. The 

 distance to the outer reef edge is 307 m. Of special note is the 

 emergent Tridacna—Acropora reef, which stretches completely 

 across the lagoon to Tridacna Islet. This reef is 1 5-20 m wide 

 (Fig. 48; Pis. 26. 63 land 1.023 m long, which, together with an 

 equal length in blind diverticulae. totals over 2 km. The 

 Tridacna clams aggregate in densities up to 80/ in' ( Sirenko & 

 Koltun, Subchapter 1.4). 



Vegetation : Kimoa has II species of plants (3 trees, 

 2 shrubs. 6 herbs). 419? of Caroline's flora There are no 

 introductions. Though small and narrow. Kimoa is well 



48 



